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Introduction: The EU New Economic Governance, Labour Law and Labour Lawyers

Marco Rocca * 1. The EU New Economic Governance and Labour Law, 10 years and two crises later

The emergence of the New Economic Governance (NEG) of the European Union (EU) during the tumultuous years of the Great Recession and the Eurozone Crisis, represented a major evolution in the history of European integration. As these evolutions often do, it brought about a new set of terms which became familiar for researchers, stakeholders and, to a greater or lesser extent, the broader public. Indeed, during the year of the previous crisis, Memoranda of Understanding (MoUs) and, for a more restricted public, Country Specific Recommendations (CSRs) became the vehicles to implement what had been identified by the European Commission and the European Central Bank (ECB) as the cure for the economic ails of the EU, namely austerity policies. These constituted a mix of reductions or freezes of public expenditures coupled with the pursuit of external competitiveness through internal devaluation, that is, the reduction of labour costs. 1 As such, the introduction and development of the NEG has led to the asymmetric reinforcement of the top-down coordination of Member States socio-economic policies, 2 where the strength of this coordination is heavily dependant upon the economic situation of a given Member State. Several studies 3 have analysed the new economic governance of the EU. focused mainly on exploring the novelties in terms of EU instruments for the coordination of budgetary and economic policies, and on their interactions with existing EU law. Similarly, other authors have explored the "constitutional mutation" of the EU 4 stemming from these instruments.

Europe (and the world) is now living through a new economic crisis, originating from the impact of the COVID-19 pandemic on all aspects of our societies. As I will discuss later in this article, the way in which the EU economic governance has handled the present crisis is strikingly different from the previous one. The different nature of the COVID-19 crisis explains much of this difference. This time the crisis was highly symmetrical, meaning that it struck all Member States in a similar way, 5 a situation which made it easier for the EU Member State to agree on a common strategy. From the point of view of the EU economic governance, several instruments were made dormant by this strategy. As it is well known, the general escape clause of the Stability and Growth Pact was triggered, 6 providing a larger margin of manoeuvre for national economic policies aimed at tackling the impact of COVID-19. On the other hand, CSRs for 2020 were deeply impacted by the crisis situation, and no new CSRs were adopted for 2021. That being said, it remains to be seen whether the arrival of the (hoped) post-pandemic economic recovery will mean the return to the prepandemic trajectories of the NEG or a rethinking of the NEG itself inspired by the pandemic experience and other political pressures. 7 The economic governance of the EU is thus at a crossroad. The main aim of this special issue is to take stock of the past impact of the NEG on four national systems of labour law and to consider the possible future scenarios on the basis of these experiences. In particular, we will consider whether and to what extent the instruments of the NEG should be included among the sources that labour lawyers ought to consider as relevant for their subject.

The first question to be addressed then is: can a clear enough link be identified between the recommendations or prescriptions of the NEG and legal changes at national level? In trying to answer this question one has to leave behind the goal of proving a direct link of causation, as proving the amount of influence that the instruments of the NEG had on domestic policies remains an insurmountable challenge. 8 The present special issue tries to address this gap by bringing together experts from each of the Member States covered in the following articles. This leads to the second question to be addressed: in the cases where the instruments of the NEG are effective in determining policies (in the area of labour law, for the purposes of the present special issue), does this change how we as labour lawyer look at these instruments? As I will describe in the next Section, the birth of the NEG during the previous crisis brought about a series of changes in the economic governance of the EU which go in the direction of reinforcing the coercive power of its tools. 9 Therefore, the dichotomy hard law / soft law does not feel adequate to capture the nature of these instruments, which indeed authors have described as "not too soft and not too hard".10 Finally, and looking to the future: should labour lawyers embrace the instruments of the NEG as a part of their field, and potentially even as a tool to foster changes at national level and improve the enforcement of labour laws? This question is strictly intertwined with the debate on the "socialisation" of the NEG. Some authors have highlighted how "social" actors, such as trade unions but also the DG Employment of the European Commission, have increasingly found their way into the mechanisms of the NEG, leading to an increased attention to social issues. [START_REF] Zeitlin | Socializing the European Semester: EU social and economic policy coordination in crisis and beyond[END_REF] This has been countered by other scholars who question the real world impact of the said "socialisation" pointing out at the continued preference of recommendations emanating from the NEG for the reduction of employment protections as well as the retrenchment of the welfare state. [START_REF] Jordan | Towards a Socialization of the EU's New Economic Governance Regime? EU Labour Policy Interventions in Germany, Ireland, Italy and Romania (2009-2019[END_REF] Furthermore, the answer to this final question will necessarily be conditional upon the future evolutions of the NEG in the post-pandemic world. After all, as it was mentioned before, the pandemic has frozen much of the workings of the NEG and this might lead to its eventual permanent weakening.

To explore these questions, the Member Sates covered by the special issue include a variety of sizes (two "smaller" Member States, Portugal and Belgium, and two "larger" Member States, Italy and France), as well as different situations vis-à-vis the instruments of the NEG, concerning notably a) the application of a Memorandum of Understanding; b) the opening and closing of excessive deficit procedures; c) the opening and closing of excessive imbalances procedure; d) the absence of ongoing procedures. Recent studies focusing on the "real" effect of the NEG highlight the importance of going beyond the formalistic analysis of the documents adopted at EU level, and to consider these in their relationship with their broader context, at both European and national level, so as to assess their impact. 13 The special issue aims at translating these insights into legal research, by looking at the impact of the NEG on labour law reforms and social policies in the abovementioned four Member States during the last decade.

To introduce the special issue, this article will describe the NEG and its instruments and highlight their strong correlation with labour laws and social policies (Section 2). It will consider (Section 3) how this relationship impacts national labour law systems and labour law as a field. The conclusions (Section 4) will be devoted to what this means for the evolution of EU labour law. Then, each separate article in the special issue will look at the situation in a specific Member State, to consider if and how the instruments of the NEG had an impact on domestic labour law and social policy. This will cover both the legal changes and the methods chosen for their implementation, as well as the political discourse surrounding these reforms -or lack thereof. The closing article will build upon the findings presented in the previous articles and assess the real impact of the NEG on national labour laws and on the study and understanding of labour law as a legal field. On this basis, it will consider if and to what extent the instruments of the NEG have their place among EU sources of labour law and social policy, and what this means for EU competences and legal remedies in these areas.

The EU New Economic Governance

The New Economic Governance includes several instruments, some of which are presently being phased out. The most infamous of these instruments, falling within the aforementioned 'phasing out' category, is the Memorandum of Understanding (MoU), examples of which have been signed between the so-called Troika and individual Member States requesting financial assistance during the crisis. These documents include an extensive list of conditionalities, that is, conditions to be fulfilled by the recipient to obtain or maintain access to financial assistance. Due to the far-reaching nature of their contents, and of their effectiveness in influencing national policies, Pecinovsky proposes to define this as the "extreme EU economic governance"14 , while De la Porte and Heins place Memoranda at the highest level of "intrusiveness" among the tools used by the EU to monitor and steer Member States' economic policies. 15 The analysis of the degree of implementation of conditionalities by the Member States covered by MoUs during the Eurozone crisis has confirmed this theoretical framework by concluding that the Member States analysed (Greece, Portugal, Cyprus, and Ireland) had "by-and-large adopted the fiscal consolidation measures prescribed by the Troika", even though the picture is less clear for so-called structural reforms. 16 It is important to note that the inclusion of conditionalities in case of financial assistance provided to Member States has been "constitutionalised"17 in the Pringle case, where the Court of Justice found that such an assistance would only be compatible with the so-called "no bailout clause" of Article 125 TFEU if accompanied by "strict conditions" which would "prompt [the recipient Member State] to implement a sound budgetary policy". 18 The last MoU expired with the end of the Greek adjustment programme. That being said, the history of the MoUs during the past crisis still casts a shadow long enough to cover the present one. Indeed, in the context of the COVID-19 pandemic, no Member State opted to have recourse to the European Stability Mechanism (ESM). This is the permanent structure created by EU Member States via an international treaty during the Eurozone crisis, with the goal to provide financial assistance. However, accessing the financial support from the ESM requires the Member State in question to be subject to strict conditionalities, such as those contained in a MoU. In this sense is has been pointed out how the past experience with MoUs and painful (and politically explosive) reforms demanded therein might have dissuaded Member States from requesting the assistance of the ESM. 19 This was made possible by the existence of other forms of financial assistance during the COVID-19 crisis, as well as by the activation of the general escape clause, which I will discuss below. As such, the discussion concerning the Portuguese MoU by Ana Teresa Ribeiro and Catarina Carvalho in this special issue is not just a retrospective analysis but also helps shed some light on the diffidence of Member States towards these instruments, as well as to consider the role of these instrument in the eventuality of their further use in the future.

A second set of instruments, by contrast, outlived the crisis and is now deeply embedded in EU economic governance thanks to the process known as the 'European Semester', an annual cycle of surveillance and enforcement of economic policies. Several instruments contribute to the cycle, namely the Country Specific Recommendations (CSRs), the Stability and Growth Pact (SGP), and the Macroeconomic Imbalances Procedure (MIP). The SGP was established in the context of the creation of the Euro, and has the aim to ensure compliance with budgetary rules by the Member States. 20 While a detailed explanation of the functioning and evolution of the SGP goes beyond the scope of the present special issue, it suffices to say that the SGP covers the rules concerning the deficits and public debts targets which Member States must strive to achieve. In case of deviations from such a budgetary trajectory, an Excessive Deficit Procedure (EDP) can be initiated against the given Member State, under the corrective arm of the SGP, leading to (so far, only theoretically) potential financial sanctions. The MIP was introduced with the so-called "six pack",21 and it is meant to prevent and correct imbalances in the macroeconomic situation of a given Member State which could have a negative impact on the budgetary or competitive position of said Member State. The assessment is based on a scoreboard which, among fourteen headline indicators, includes "social" ones such as the unemployment and activity rate, as well as the rate of longterm and youth unemployment.

The special issue focuses mainly on Country Specific Recommendations (CSRs), which are annual recommendations drafted by the Commission (in May) and adopted by the by the Economic and Financial Affairs Council configuration of the Council (in July). The term 'Recommendation' is used somewhat loosely in this context, given that failure to comply can theoretically lead to sanctions, although this has never happened so far, at least in some instances. In particular, CSRs related to compliance with the budgetary criteria established by the Stability and Growth Pact or to the Macroeconomic Imbalances Procedure can lead to financial sanctions, which, having been proposed by the Commission, can only be rejected by a qualified majority in the Council. Member States that are part of the Eurozone risk fines equal to 0.2 per cent (SGP) or 0.1 per cent of GDP (MIP), 22 which, once proposed by the Commission, can only be reversed by a qualified majority in the Council. 23 Furthermore, since 2014 a Member State risks losing access to EU structural funds if they fail to comply with CSRs. 24 One can also discern an appetite to further strengthen the link between 'EU money' and compliance with CSRs, further reinforcing sanctions arsenal, in a recent report by the EU Court of Auditors. 25 This whole approach is part of what has been deemed a "money for reforms" strategy pursued by the EU Commission.26 Such a strategy has been highlighted in most areas of EU spending, leading to 75% of the EU budget being now accompanied by some form of conditionalities. 27 As I mentioned in the introduction, this creates a situation where the usual categories of "soft" and "hard" law might fail to capture the reality of the phenomenon of the NEG and its interaction with national policies. Building on previous literature on this categorisation, Bekker suggests seeing the space between "soft" and "hard" law as a continuum, which can be investigated on the basis the nature and characteristics of the given instruments. 28 Notably, these can be placed on said continuum on the basis of the existence and precision of an obligation, the existence and the nature of enforcement mechanisms, as well as the degree of "centralisation" in their drafting. 29 While it might be impossible to pinpoint the exact nature of a given instrument or CSR, this framework helps overcoming the limitation of the strict dichotomy between "soft" and "hard" law. In light of the focus of the present special issue on labour law systems, one should also keep in mind how labour lawyers are used to include issues of real-world or economic power in their assessment of legal situations.

To a certain extent, the management of the present crisis by the EU economic governance represents deviation from this pattern. As it was mentioned before, the activation of the general escape clause has suspended much of the instruments related to budgetary of fiscal matters, and this will remain in place as long as it is deemed necessary to enact fiscal measures to fight the COVID-19 pandemic and its effects on the economy. However, it is worth mentioning that several signs point to the fact that this deviation might only be temporary. First, the 2020 CSRs included Recitals pointing to the fact that Member States are still expected to follow the 2019 recommendations when it comes to the areas covered by the general escape clause. [START_REF] Rainone | An overview of the 2020-2021 country-specific recommendations (CSRs) in the social field[END_REF] What is more, the recent Communication from the Commission on national draft budgetary plans, [START_REF]Communication from the Commission to the European Parliament, the Council, and[END_REF] includes a warning for several Member States (Belgium, France, Greece, Italy, and Spain) to "preserve prudent fiscal policy" when taking budgetary measures to address the socio-economic effect of the COVID-19 pandemic. 32 In the same passage, Italy also received a specific recommendation to "limit the growth of nationally financed current expenditure". This suggests an intention, at least from the Commission, to return to the previous approach to economic governance once the present crisis is over. In preparing this special issue we set out from the assumptions that a) the NEG would therefore remain relevant after the COVID-19 crisis is behind us [START_REF]Potentially[END_REF] and b) the trajectory of the NEG, and of CSRs in particular, would follow what was happening before the crisis.

Coming to the actual strategy put in place via the NEG during the crisis, I will only focus on those instruments which are relevant for the special issue. This is to say that the very important role played by the ECB in the initial reaction to the impact of the pandemic, through the provision immediate liquidity 34 and the launching of the Pandemic Emergency Purchase Programme (PEPP), [START_REF] Ecb | ECB announces €750 billion Pandemic Emergency Purchase Programme (PEPP)[END_REF] will fall outside of the scope of this article. More importantly, for the topic of the special issue, the Commission proposed to activate the general escape clause of the SGP on 20 March 2020, [START_REF]Communication to the Council on the activation of the general escape clause of the Stability and Growth Pact[END_REF] and this was supported by the Council just a few days later. [START_REF]Statement on the Stability and Growth Pact in light of the Covid-19 crisis' 23[END_REF] The activation of the clause provides a larger budgetary margin of manoeuvre for Member States in order to deal with periods of severe economic downturn, although it does not change the long-term trajectory that Member States should follow under the SGP. 38 While the clause is activated for all Member States, it has been pointed out that the actual measures enacted at national level have been largely asymmetric, due to the different budgetary situation of Member States when they entered the COVID-19 crisis. 39 The pandemic saw also the creation of the SURE instrument, 40 aimed at providing Member States with a less expensive way to finance temporary unemployment benefits introduced to address the economic crisis brought about the by pandemic. [START_REF] Detienne | Zone euro, assurance chômage européenne et instrument SURE : L'effectivité du droit de la sécurité sociale est aussi une question économique[END_REF] Looking back to the question of conditionalities, this new instrument shows a different approach to the issue, where the respect of Article 125 TFEU is ensured by the fact that the funds provided by SURE can only be allocated to very specific expenditures, that is, temporary unemployment schemes.

As such, it does not pose a risk to the no-bailout clause or to the commitment of Member States to pursue a strategy of sound public finances (Article 119 para. 3 TFEU).

The 2020 CSRs were dominated by broader pandemic context. The activation of the general escape clause meant that the macroeconomic recommendations package was substantially reduced and replaced by a standardised formula. On the other hand, many recommendations were aimed at tackling the socio-economic impact of the crisis, such as by ensuring the adequacy of social protection systems and income support mechanisms. [START_REF] Rainone | An overview of the 2020-2021 country-specific recommendations (CSRs) in the social field[END_REF] In 2021 no CSRs were drafted, the exercise being essentially absorbed the functioning of the Recovery and Resilience Facility (RRF) 43 which is defined as the "centrepiece" of the Next Generation EU initiative, aimed at tackling the economic consequences of the COVID-19 crisis. [START_REF]Recovery plan for Europe[END_REF] The RRF is a temporary instrument aimed at making financial resources available to Member States to support the post-crisis recovery. More specifically, the RRF makes available to Member States €385.8 billion in loans and €338 billion in grants. [START_REF]The Recovery and Resilience Facility[END_REF] As pointed out by Vanhercke and Verdun, there is an intrinsic link between the functioning of the RRF and the European Semester, [START_REF] Vanhercke | From the European Semester to the Recovery and Resilience Facility. Some social actors are (not) resurfacing[END_REF] which made the adoption of CSRs for 2021 redundant. In particular, the RRF Regulation explicitly refers to the Semester both in the Recitals and in the legal text, and it states notably that the recovery and resilience plans, which Member Sates have to draw up to access the financial support from the RRF, "shall be consistent with the relevant country-specific challenges and priorities identified in the context of the European Semester, as well as those identified in the most recent Council recommendation on the economic policy of the euro area for Member States whose currency is the euro". 47 This approach confirms the abovementioned strategy of "money for reforms" and reinforces the understanding of the present special issue concerning the continuity between the content of the NEG pre-and post-pandemic.

Labour law and the NEG

As discussed in the previous section, the NEG was largely built during the Great Recession and the Eurozone crisis, either via the creation of new instruments or by reenforcing existing ones. This fact should be kept in mind when assessing the vision of labour law and social policies in general which stems from the instruments of the NEG. In particular, the diagnosis of the causes of the crisis, under what Fitoussi and Saraceno called the "Berlin-Washington Consensus", [START_REF] Saraceno | European economic governance: the Berlin-Washington Consensus[END_REF] meant that labour law and social policies reforms were to contribute to internal devaluation, [START_REF] Deakin | The sovereign debt crisis and the evolution of labour law in Europe[END_REF] by bringing about the reduction of labour costs and increasing the downward flexibility of wages in a given Member State. In the words of the Commission, this was aimed at "improving external competitiveness through supporting labour supply and increasing wage flexibility". [START_REF]The Economic Adjustment Programme for Greece, Second Review[END_REF] The inertia of this initial trajectory, visible, as I discuss in a moment, in both MoUs and the early CSRs, had a long-lasting impact on the content of the prescriptions related to these areas under the NEG. This also had an impact on the understanding of labour lawyers of the threat posed by these instruments for the field of labour and social rights, giving the impression that the European Union had opted for what could be called, following Hepple's categorisation, a competitiveness-based regulation, instead of a rights-based one. [START_REF] Heppl | Rights at Work Global, European and British Perspectives[END_REF] The story surrounding the MoUs signed during the Eurozone crisis is relatively well known.

What is important for the purposes of the present special issue is that labour and employment matters figured to an important degree among the conditionalities included in these documents. [START_REF] Sapir | The Troika and Financial Assistance in the Euro Area: Successes and Failures[END_REF] In particular, in the context of the three MoUs (2010, 2012, 2015) concluded between the Troika and the various Greek governments, the conditionalities focused on wages, collective bargaining and protection against dismissal. [START_REF] Theodoropoulou | National social and labour market policy reforms in the shadow of EU bail-out conditionality: The cases of Greece and Portugal[END_REF] The Memorandum signed by the Portuguese government in 2011 contained similar labour law conditionalities, with the exception of minimum wage conditionalities, notably in the direction of reducing protection against dismissal and decentralising collective bargaining. [START_REF] Ribeiro | Crisis and labour law -Recent developments in Portuguese labour law[END_REF] The article by Ana Teresa Ribeiro and Catarina Carvalho in this special issue provides further details on the latter MoU, which confirms the said trajectory of the NEG prescriptions during the Eurozone crisis.

Turning to CSRs, a large share of these recommendations is related to labour rights, employment and social policies. This is coherent with the approach we just outlined in the context of MoUs, and it confirms the continuity between the two sets of instruments. A further confirmation of this also comes from the fact that Member States already bound by the MoU in the context of a structural adjustment plan, do not receive CSRs. In particular, research from the European Trade Union Institute shows that between 40 and 63 per cent of CSRs adopted over the past decade (2011-2019) have focused on social aspects. 55 Focusing on CSRs in the areas of labour law and employment policy, one can identify three main groups of recommendations. The first deals with wages. CSRs in this area, particularly in the years of the second Barroso Commission, focused on the revision of wage indexation mechanisms, with the aim of reducing or eliminating such mechanisms. 56 The following years marked a modest shift, with CSRs now encouraging Member States to 'ensure that wages can evolve in line with productivity'. [START_REF]For instance[END_REF] In this same group we also include CSRs aimed at the decentralisation of collective bargaining systems, that is, requesting a shift from sectoral to company collective bargaining, [START_REF] Schulten | A new European interventionism? The impact of the new European economic governance on wages and collective bargaining[END_REF] which are included in the first years of the CSRs (up to 2014). [START_REF]Part 2. From imposed restrictions of the right by EU Member States towards a social economic governance[END_REF] This are will be particularly visible through the present special issue since, as the authors note in their respective articles, all Member States covered in the issue were interested, to a greater or lesser extent, by recommendations concerning the organisation of their system of collective bargaining.

A second group of CSRs revolves around employment protection legislation, focusing on rules on dismissal. The relaxation of dismissal rules for open-ended contracts is often the focus of these recommendations, justified either as a measure to combat segmentation of the labour market 60 or to encourage the hiring of workers with open-ended contracts. 61 The third group of CSRs covers areas related to employment policies, with a specific focus on improving the labour market participation of women, 62 older [START_REF]These cover measures concerning lifelong learning, active labour market policies, and vocational education[END_REF] and younger [START_REF]Covering measures such as the improvement of apprenticeship and vocational education, the introduction of a youth guarantee, and the improvement of the quality of education[END_REF] workers.

This short overview shows why the NEG matters for labour law and labour lawyers. Large and important areas of labour regulations and practices are directly influenced by instruments whose ability to influence national policies goes beyond the one of mere "soft law" instruments without being formalised in a binding legal instrument, leading to difficulties in exerting judicial control, for instance when it comes to respecting fundamental social rights. [START_REF] Kilpatrick | Are the bailouts immune to EU social challenge because they are not EU law?[END_REF] The same can be said for social actors, such as national trade unions, who can find it difficult to mobilise their power resources, often anchored in national practices and institutions, to influence the outcomes of New Economic Governance and its impact on national labour laws. [START_REF] Copeland | The European Semester and EU Social Policy[END_REF] This is not the first time labour lawyers have been confronted with 'soft law' instruments in relation to EU social policy. Indeed, the Open Method of Coordination (OMC) received significant attention in the first decade of the new millennium. [START_REF] Ashiagbor | Soft Harmonisation: The Open Method of Coordination in the European Employment Strategy[END_REF] It is also not the first time that labour laws are assessed through their impact on competitiveness, such as in the experience of the Doing Business index of the World Bank. [START_REF] Adams | Quantitative Labour Law[END_REF] The integration of these aspects in the much more penetrating machinery of economic governance, however, and the ever present (if, so far, theoretical) threat of sanctions, constitute a marked difference with existing instruments. As I pointed out before, this threat is dependent upon the legal basis which underpins the given CSRs. Notably, only CSRs based on the SGP or the MIP can lead to financial sanctions. That being said, looking at the 2013 cycle of CSRs, Bekker has concluded that 39 of 78 CSRs linked to employment and social policies were based on these two instruments. This confirms the "proximity" of many areas of labour law and social security with budgetary rules (for instance, the financing of the welfare state) and with the macroeconomic, and notably external, position of a Member State (wage dynamics).

The increased focus on social aspects has led some authors to conclude that we are witnessing a 'socialisation' of New Economic Governance, balancing social retrenchment with social investment, and rediscovering the 'flexicurity' approach. [START_REF] Bekker | Flexicurity in the European Semester: still a relevant policy concept?[END_REF] In purely quantitative terms, the number and scope of socially orientated CSRs have been reinforced from 2011 to 2014, while during the period 2017-2020, CSRs dedicated to, or at least linked with, social aspects represent more than the half of all CSRs addressed to Member States. [START_REF] Hacker | A European Social Semester? The European Pillar of Social Rights in practice[END_REF] This was saluted by the European Trade Union Confederation (ETUC) which, in its Action Programme 2019-2023, asserted that 'a process of making the European Semester more social has started', all the while lamenting the enduring primacy of "restrictive macroeconomic policy" and the "liberal market bias" of New Economic Governance. [START_REF] Etuc | ETUC Action Programme[END_REF] Indeed, this re-orientation was accompanied by a reductionist vision of social objectives and rights, henceforth centred on the idea of a floor of rights for the most vulnerable categories of workers (and citizens).

These parallel trends are confirmed by studies dealing with more recent cycles of the Semester. 72 Other authors have criticised the 'socialisation' conclusion, reaffirming the need to go beyond the simple categorisation of CSRs as 'social' on the basis of their literal context, to read them in light of their accompanying documents, different level of (potential) sanctions, and impact on the national environment. [START_REF] Jordan | Towards a Socialization of the EU's New Economic Governance Regime[END_REF] In one example, this approach made it possible to determine that a seemingly "neutral" prescription on the need to improve "transparency" in the setting of minimum wages was instead meant to create obstacles to the unilateral increase of the minimum wage proposed by a centre-left government. 74 Another important element to keep in mind when considering the 'socialisation' of the semester is that, even in the face of an unprecedented economic and social crisis, the 2020 CSRs maintained that Member States would still be expected to implement the recommendations adopted in 2019. 75 Finally, the 'socialisation' of New Economic Governance also covers the increased participation of social partners in the process. [START_REF] Zeitlin | Socializing the European Semester: EU social and economic policy coordination in crisis and beyond[END_REF] In 2016, a quadripartite statement on a 'New Start for Social Dialogue' was signed, with the aim of improving said participation. [START_REF]A New Start for Social Dialogue, Statement of the Presidency of Council of the European Union, the European Commission and the European Social Partners[END_REF] This included a commitment of EU institutions (notably, the Council and the Commission) to enhance the involvement of Union level social partners in New Economic Governance, as well as the involvement of social partners at national level in the relevant steps of the European Semester, such as the process of drafting national reform plans and implementing CSRs. This followed a period (2011-2013) in which said participation was considered to be inadequate by social partners and academic observers. [START_REF] Sabato | Listened to, but not heard? Social Partners' multilevel involvement in the European Semester[END_REF] A more recent study by Eurofound, however, focusing on participation in the 2017 round of CSRs, found that social partners in a large number of Member States still lamented insufficient involvement in the implementation of policy reforms at national level in the context of the Semester. 79 These criticisms generally point to a merely formal process of consultation, so that claims of 'socialisation' based on the mere 'involvement' of social partners at some point of the process should be considered carefully. Also, the procedural aspect of socialisation can sometimes be used to the detriment of the substantive one. For instance, Bekker highlights how, in reaction to a 2014 CSR directed to the Netherlands and recommending to increase wages, the Dutch government pointed out that the area was a competence of social partners. The Commission simply accepted this argument and did not issue that CSR again in the following years. [START_REF] Bekker | Hardening and softening of country-specific recommendations in the European Semester[END_REF] That being said, some measure of a more 'social' approach can be found when looking at some areas of social security. These CSRs often focus on the establishment/improvement of a minimum level of protection aimed at poverty alleviation. 81 In what can be assumed to be a reaction to the specific situation of the COVID-19 crisis, a more visible focus on these instruments can be identified in the 2020 round of CSRs. [START_REF] Rainone | An overview of the 2020-2021 country-specific recommendations (CSRs) in the social field[END_REF] On the other hand, in the area of pensions, CSRs from pre-pandemic years have continued to be inspired by the logic of austerity, recommending in particular to increase the pension age, reduce or eliminate possibilities for early retirement, and ensure the (financial) sustainability of pension systems. [START_REF] Clauwaert | The country-specific recommendations (CSRs) in the social field. An overview and comparison[END_REF] Coming to the present days, as discussed in the previous section, CSRs for 2021 have been absorbed into the RRF. Research from the European Social Observatory highlights how the absence of quantitative social targets (as opposed to the case of green and digital policies) has accentuated the importance of pre-pandemic CSRs. [START_REF] Vanhercke | From the European Semester to the Recovery and Resilience Facility[END_REF] A delegated regulation adopted by the Commission in September 2021 provides a methodology to identify social expenditures in national plans presented under the RRF, with a special flagging for initiatives focusing on gender equality, children and the youth. 85 However, early analyses of national plans show that social investment and reforms in the areas of labour and social policies do not occupy an important place in these plans, leaving aside those related to healthcare which are clearly related to the pandemic context. [START_REF] Corti | Steering and Monitoring the Recovery and Resilience Plans[END_REF] 4. The EU New Economic Governance: a chapter or a footnote for EU Labour Law

In the previous section I have (hopefully) demonstrated why the NEG matters for labour law and labour lawyers. This leaves two further questions to be addressed.

The first is related to the actual effectiveness of the instruments of the NEG. To address this it might be helpful to consider separately MoUs and CSRs. This is because the effectiveness of MoUs in modifying national policies stems from the specific position of weakness of the recipient Member States. Therefore, for this set of instruments it is relatively easy to conclude that they do have a potentially profound impact on national policies, 87 an impact that sometimes outlasts even the duration of the adjustment programme itself. [START_REF] Moury | When the Lenders Leave Town: Veto Players, Electoral Calculations and Vested Interests as Determinants of Policy Reversals in Spain and Portugal[END_REF] On the other hand, the research on the effective implementation of CSRs provides a picture which is much less clear. As observed by Bekker in the context of the strengthening of the NEG, "stricter rules do not necessarily mean automatic changes in national policy responses". [START_REF] Bekker | European socioeconomic governance in action: coordinating social policies in the third European Semester[END_REF] Indeed, the dataset compiled by Efstathiou and Wolff, covering CSRs from 2013 to 2017, suggests that on average the Commission reported "limited progress" or "some progress" (thus, falling short of "substantial progress", let alone "full implementation") for the implementation of CSRs. [START_REF] Efstathiou | Is the European Semester effective and useful?[END_REF] The authors also point to a relatively higher degree of implementation when taking into account a longer time frame, which still, on average, falls short of showing a "substantial progress". Interestingly, for the present special issue, the same research finds a higher degree of implementation for CSRs related to employment laws and labour markets than those concerning pensions and unemployment benefits. These results were essentially replicated by Clauwaert and Al-Kadi, who only focused on "social" CSRs. [START_REF] Clauwaert | Socialising the European Semester? Measuring Member States' implementation of country-specific recommendations in the social policy field[END_REF] The 2020 Report from the Court of Auditors, which looks at CSRs between 2011 and 2018, reaches similar conclusions. 92 Importantly, looking at the whole period the report indicates that only 9% of CSRs have been "fully implemented" while 17% fall into the "substantial progress" category.

This relatively low level of implementation seems to suggest that the impact of CSRs is limited. As such, the machinery we have sketched in the previous sections might indeed hold little interest for labour lawyers. On this background, the contributions in this special issue focusing on specific national experiences will provide a different approach, based on case studies of specific contexts and recommendations instead of quantified global evaluations. Furthermore, the analysis we have seen so far are, by necessity, retrospective. It remains to be seen whether the continued pursuit of a "money for reforms" strategy might increase the effectiveness of CSRs once the general escape clause will not be applicable, while a large number of Member States might be emerging from the COVID-19 crisis in a worse budgetary situation. As pointed out by Vanhercke and Verdun, increasing the link between EU funding and CSRs, the RRF being the last example of this trajectory, might create a 'harder mode of soft governance'. 93 Together with Mélanie Schmitt, we come back to this in the closing contribution of this special issue.

The second question is related to the role of the NEG in the context of EU labour law. Is the impact of EU policies on national labour law systems conveyed more and more by the instruments of the NEG instead of the classic legal instruments (mainly, Directives)? This is the "displacement" effect described by Kilpatrick,94 in its meaning of "moved elsewhere".

Of course the answer to this question must take into account the relative effectiveness of CSRs we just highlighted. However, the role of the NEG has institutional aspects which remain relevant even in light of a low implementation rate of its prescriptions at national level. On of these aspects is related to the fact that, as I described in section 2 while presenting the main topics covered by CSRs, through the instruments of the NEG, EU institutions routinely intervene in areas which fall outside of the competences established by the Treaties. Wages are the best example of this situation and are also particularly interesting as all Member States which will be analysed in this special issue were covered by CSRs in this area. The "temptation", in particular for the EU Commission, to use the instruments of the NEG to implement its labour policies also stems from the fact that CSRs are easier to adopt than standard binding instruments. Finally, the impact of the displacement might also be amplified by the low rate of implementation that was just discussed. This risk is particularly visible in the context of the European Pillar of Social Rights. Indeed, the implementation of the principles of the Pillar is intrinsically linked to the European Semester, the former being conceived as the "social" counterbalance to the strictly economic approach of the latter. 95 As Clauwaert and Al-Kadi have pointed out, this connection makes it so that the weak implementation of CSRs calls into question the added value of the Semester for the protection of the fundamental rights embedded in the Pillar. 96 By exploring the actual impact of the NEG on national labour law systems, the present special issue will thus contribute to our understanding of the potential of the NEG both in its ability to shape labour and social rights and in its potential role to promote them.

  93 B. VANHERCKE, A. VERDUN, A. ATANASOVA, S. SPASOVA and M. THOMSON, 'From the European Semester to the Recovery and Resilience Facility', p. 37 94 C. KILPATRICK, 'The displacement of Social Europe: a productive lens of inquiry', European Constitutional Law Review, 2018, no. 14, 62-74. 95 See European Commission, Communication from the Commission to the European Parliament, the Council and the European Economic and Social Committee, Monitoring the implementation of the European Pillar of Social Rights, COM (2018) 130 final, 13 March 2018.

96

S. CLAUWAERT and R. AL-KADI, 'Socialising the European Semester?, 20.

B. VANHERCKE, A. VERDUN, A. ATANASOVA, S. SPASOVA and M. THOMSON, 'From the European Semester to the Recovery and Resilience Facility', p. 8.

P. PECINOVKSY, 'EU economic governance and the right to collective bargaining. Part 1. Standard and extreme governance and the indicators and limits of the right to collective bargaining', European Labour Law Journal, 2018, vol. 9, no. 4, p. 375.

C. DE LA PORTE and E. HEINS, 'A new era of European Integration? Governance of labour market and social policy since the sovereign debt crisis', Comparative European Politics, 2015, vol 13, no. 8, 13.

A. SAPIR, G. WOLFF, C. DE SOUSA and A. TERZI, The Troika and Financial Assistance in the Euro Area: Successes and Failures, Brussels, Bruegel, 2014, 58.

See T. CAPETA, 'The Role of Courts in Economic Governance in the European Union', in F.j. CARRERA HERNÁNDEZ (ed.), Towards a New Government of the Economy in the European Union?, Aranzadi, Cizur Menor, 2018, 155-190; M. DAWSON and F. DE WITTE, 'Constitutional Balance in the EU', Modern Law Review, 2013, no. 76, 817-844.

CJEU, Case C-370/12, Thomas Pringle v Government of Ireland, 27 November 2012, para. 136-137.

P. DERMINE and M. MARKAKIS, 'EU Economic Governance and the COVID-19 Crisis: Between Path-Dependency and Paradigmatic Shift', International Journal of Public Law and Policy, (2020) vol. 6, no. 4, 333.

 20 A. VERDUN, 'The building of economic governance in the European Union', Transfer, 2013, vol. 19, no. 1,

28 21 Including five Regulations and a Directive: Regulation (EU) no. 1173/2011, 16 November 2011; Regulation (EU) no. 1174/ 2011, 16 November 2011; Regulation (EU) no. 1175/2011, 16 November 2011; Regulation (EU) no. 1176/2011, 16 November 2011; Regulation (EU) no. 1177/2011, 8 November 2011; Directive no. 2011/85/EU, 8 November 2011.

Depending on whether the CSR is linked, respectively, to an Excessive Deficit Procedure or to an Excessive Imbalances Procedure.

C. DE LA PORTE and E. HEINS, 'A new era of European Integration? Governance of labour market and social policy since the sovereign debt crisis', 12.

V. VIȚĂ, 'Revisiting the Dominant Discourse on Conditionality in the EU: The Case of EU Spending Conditionality', Cambridge Yearbook of European Legal Studies, 2017, no. 4, 1-28.

European Court of Auditors, The European Semester -Country Specific Recommendations address important issues but need better implementation, 2020, 35: "The Commission should strengthen the link between EU funds supporting reform processes in Member States and Country Specific Recommendations. CSRs should be taken into consideration in the different stages of budgetary processes".

B. VANHERCKE, A. VERDUN, A. ATANASOVA, S. SPASOVA and M. THOMSON, 'From the European Semester to the Recovery and Resilience Facility', 34.

V. VIȚĂ, 'Revisiting the Dominant Discourse on Conditionality in the EU: The Case of EU Spending Conditionality', 9.

S. BEKKER, 'Hardening and softening of country-specific recommendations in the European Semester', West European Politics, vol. 44, no. 1, 2021, 118.

Ibidem. The last criterion ("centralisation") refers to the ability (or lack thereof) of national level actors to influence the drafting of the CSRs.

S. CLAUWAERT, 'The country-specific recommendations (CSRs) in the social field. An overview and comparison. Update including the CSRs 2019-2020', ETUI Background Analysis, 2019, no. 1, 11; S.

S. CLAUWAERT, 'The country-specific recommendations (CSRs) in the social field. An overview and comparison. Update including the CSRs 2019-2020'.


Romeric Gay
email: romeric.gay@st.com

Vincenzo Della Marca
email: vincenzo.della-marca@im2np.fr

Hassen Aziza
email: hassen.aziza@im2np.fr

Arnaud Regnier
email: arnaud.regnier@st.com

Stephan Niel
email: stephan.niel@st.com

Abderrezak Marzaki
email: abderrezak.marzaki@st.com

Romeric Gay Stmicroelectronics

Benchmarking and optimization of trench-based multi-gate transistors in a 40 nm non-volatile memory technology

Keywords: Multi-gate, Triple gate transistor, Dual gate transistor, Trench, Non-volatile-memory

come

I. INTRODUCTION

The continuous scaling of physical feature sizes of silicon-based MOSFET transistors is highly desirable in the semiconductor industry in order to increase functionality and reduce the cost of a large variety of integrated circuits and systems. However, continuous scaling has to solve physical limits and challenges imposed by the CMOS manufacturing process [START_REF] Seshan | Limits and Hurdles to Continued CMOS Scaling[END_REF]. The latter are dictated by the optical lithography which requires new methods such as EUV laser when scaling down below 10 nm [START_REF] Watanabe | Current status and prospect for EUV lithography[END_REF] and ultimately by the manufacturing cost. Scaling directly impacts the physical parameters of integrated devices such as the gate oxide thickness, the leakage current [START_REF] Koh | Limit of gate oxide thickness scaling in MOSFETs due to apparent threshold voltage fluctuation induced by tunnel leakage current[END_REF], and the short-channel effects [START_REF] Chaudhry | Controlling short-channel effects in deep-submicron SOI MOSFETs for improved reliability: a review[END_REF]. Therefore, as most of conventional transistor parameters are now reaching fundamental limits, novel transistor architectures are highly desirable to meet cost and performances requirements of high-volume products. This is particularly true for embedded Non-Volatile Memory (e-NVM) technology which has generated interest as a potential solution for several key mass market including Internet of Things (IoT) applications.

In this context, alternatives to classical planar MOSFET have emerged in the last few years such as multiple-gate transistor [START_REF] Ferain | Multigate transistors as the future of classical metal-oxide-semiconductor field-effect transistors[END_REF], triple gate transistor [START_REF] Doyle | Tri-Gate fully-depleted CMOS transistors: fabrication, design and layout[END_REF], gate all around [START_REF] Kim | Vertically Stacked Gate-All-Around Structured Tunneling-Based Ternary-CMOS[END_REF], FinFET [START_REF] Natarajan | A 14nm logic technology featuring 2nd-generation FinFET, air-gapped interconnects, selfaligned double patterning and a 0.0588 µm2 SRAM cell size[END_REF]. Alternatively, and mostly for integrated passive devices, deep trenches are used in various ways, including as insulators, sensors, or capacitors to increase integration density [START_REF] Banzhaf | Post-trench processing of silicon deep trench capacitors for power electronic applications[END_REF].

The aim of this work is to compare the performances of three Multi-Gate Transistors (MGT) architectures manufactured in a 40 nm e-NVM. Multi-Gate Transistors are fabricated directly from a classical MOS transistor where lateral conduction channels are added by integrating deep trench transistors alongside the planar transistor channel. After fabrication, electrical measurements are performed for each MGT transistor configurations to assess their performances versus the equivalent planar transistor considered as the reference architecture.

Section II presents the trench transistor concept, its manufacturing process and the novel MGTs architectures based on trench transistor structure. In Section III, we report an experimental analysis of electrical parameters for different MGTs. The section IV discusses the proposed MGTs architectures. Finally, Section V concludes this paper.

II. TRENCH-BASED MGT

A. Trench transistor manufacturing process

The trench transistor uses a specific process steps already available in the targeted eSTM TM Non-Volatile Memory manufacturing process [START_REF] Niel | Embedded Select in Trench Memory (eSTMTM), best in class 40nm floating gate based cell: a process integration challenge[END_REF]. Trenches fabrication includes different actions. Firstly, the definition of active and oxide Shallow Trench Isolation (STI) regions presented in Fig. 1. (a) is realized. Then, a photolithography step is carried out and the trench etching is performed (Fig. 1. (b)). Trench oxide is grown at the bottom and along sidewalls of the trench which is then filled with an in-situ doped polycrystalline silicon (Fig. 1c) to build the trench transistor gate. Finally, Chemical and Mechanical Polishing (CMP) is performed to remove the polysilicon excess.

B. MGT transistor architectures

In order to design the different MGT architectures, we started from a planar gate transistor denoted Single Gate Transistor (SGT) (Fig. 2. (a)). The SGT is integrated in the NVM cell environment (as already mentioned), so it uses the process flow of the NVM environment. No additional steps or masks are required to fabricate the device. Therefore, the SGT is processed from the Flash floating gate stack presented in Fig. 2. (a). It consists of a tunnel oxide, a first polysilicon layer (poly1), an oxide/nitride/oxide (ONO) inter-poly dielectric and a last polysilicon layer (poly2). Note that for this device, both poly1/poly2 are shorted, and the contact is performed through the poly2/ONO stack. Finally, source and drain are created with n+ implantations.

For the MGT, trench transistors are integrated at both sides of the SGT architecture represented in Fig. 2

. (b). This architecture is referred to as Triple Gate Transistor (TGT).

The resulting TGT has three conduction channels, and therefore it can be considered as three MOS transistors connected in parallel. All the conduction channels are localized between the drain and the source. One is controlled by the planar gate (PG) (poly1+tunnel oxide) and its conduction path is represented by the blue arrow in Fig. 2 (c). The second and third channels are controlled by the gate trench (TG). The current path of one single TG channel is represented by the orange arrow in Fig. 2 (c). The second TG current path is not represented (hidden by the active region). Note that it is possible to integrate only one trench transistor into the SGT architecture. In this case, the final device owns two gates and so is referred to as Dual Gate Transistor (DGT).

C. MGT samples design

In this section, we describe the design of the studied devices. The first layout presented in Fig. 3. is the SGT structure which is the reference architecture, with only one planar gate width (WP) of 200 nm. The second architecture presented in Fig. 3. is the DGT structure which corresponds to the SGT with one integrated trench transistor. The DGT planar width is reduced to 180 nm because of vertical trench integration. One can notice that the final DGT width depends on the PG plus the vertical TG channel widths. The third architecture presented in Fig. 3. is the TGT1 structure which is composed of the SGT planar transistor and two vertical trench transistors. In this case the TGT1 width includes the widths of the two TG and the WP of the PG which is defined by the space between the trenches (160 nm). Finally, the fourth architecture is the TGT2 and corresponds to the TGT1 architecture with a smaller WP=110 nm. For each architecture presented in Fig. 3, the equivalent electrical schematic is provided to highlight the number of transistors as well as the area. The SGT and the DGT have a similar footprint, 0.304 µm² and 0.338 µm² respectively. Thus, the integration of one trench has a slight impact on the area with respect to the SGT transistor. Regarding the TGT1 structure, the integration of a double trench results in an area increase. The scaling of WP in the TGT2 enables a gain of 10% in terms of occupied surface.

III. EXPERIMENTAL RESULTS

The aim of this section is to study the performances of the three MGT architectures. This evaluation is conducted by analyzing drain current (ID) versus gate voltage (VG) electrical characteristics. Performance parameters extracted from the experimental results will be compared and discussed. The SGT being considered as the reference transistor. For the multi-gate transistors, TG and PG are shorted to study the equivalent transistor behavior.

A. MGT transistors benchmark

Fig. 4 shows ID-VG electrical characteristics in linear and saturated mode with drain voltages (VD) of 0.1 V and 2 V respectively for: (a) SGT, (b) DGT, (c) TGT1 and (d) TGT2. A summary of the most relevant parameters in saturated mode is shown in Table I. The ON current parameter (ION) is extracted for VG = 4 V and the OFF current parameter (IOFF) for VG = 0 V. The threshold voltage (Vt) is measured at the maximum of the transconductance, while the subthreshold slope (Ss) is extracted on two decades of drain current characteristics from 0.1 nA to 10 nA.

In Fig. 4, the standard SGT (Fig. 4. (a)) and the DGT (Fig. 4. (b)) characteristics are reported. The DGT conduction current is higher than the SGT as we can see on linear curves. This difference is due to the presence of the vertical trench transistor which leads to an additional conduction channel for the DGT architecture. This conduction current increase is also observed in Fig. 4. (c)-(d) for both triple gate transistor configurations TGT1 and TGT 2. It is more pronounced because each TGT architecture benefits from a triple channel conduction. These observations are confirmed by the ION current parameter extracted in saturated mode presented in Table I. Indeed, we observe that the TGTs structures provide an ION driving current three times higher than the SGT ION and two times higher than the DGT one. One can notice that the driving current of the TGT1 is close to the TGT2 with a smaller area.

Regarding the IOFF parameter in Table I which represents the leakage current, the SGT and DGT values are equivalent (IOFF = 3E-14 A). Thus, the integration of one trench transistor does not impact the device leakage current. However, we observe an increase of one decade for the TGT1 architecture and two decades for the TGT2 architecture. These variations are due to the two trenches integration on the planar gate structure, inducing the hump effect. This effect is discussed in the next paragraph. Note that the leakage current increases when the planar width is decreased.

In Fig. 4. (a)-(d) for drain current characteristics in logarithmic scale, we can notice a variation of subthreshold slopes (Ss parameter in Table I) for the different architectures. We observe that Ss decreases with the number of integrated trenches. Indeed, the Ss value of the DGT device is 95 mV/dec, lower than the SGT one which is equal to 107 mV/dec. Besides, both Ss values of the TGT architectures are lower than the DGT.

In Fig. 4. we can note at the beginning of ID-VG characteristics on logarithmic blue curve, a hump effect for the TGT is present (Fig. 4. (c)-(d)) while is less pronounced in the DGT characteristics (Fig. 4. (b)) and absent for the SGT (Fig. 4. (a)). This hump effect is explained by the abrupt transition between the active region and the trench transistor [START_REF] Schwantes | Characterization of a new hump-free device structure for smart power and embedded memory technologies[END_REF]. This latter leads to an overconsumption of oxide at the active area corner, inducing a gate electric field modification at the channel edge. Moreover, this topologic modification can reduce the TG channel doping. Therefore, all these contributions activate the parasitic transistor at the active/trench corner with a reduced threshold voltage. This effect has an impact on the subthreshold region and can explain the IOFF leakage current increase for the TGT architectures [START_REF] Joly | Impact of hump effect on MOSFET mismatch in the sub-threshold area for low power analog applications[END_REF].

The following conclusions can be extracted from Table I. A higher threshold voltage is measured for the SGT (Vt = 1.42 V) compared to the TGT architectures (Vt = 0.95 V for TGT1 and Vt = 1.06 V for TGT2). This variation can be explained by the different planar and vertical transistors parameters depending on the TGT architecture. Indeed, the PG width is reduced by the trenches integration. For the TG, its width corresponds to the source and drain implantation depth and its length corresponds to the source/drain space. Moreover, the trench oxide thickness slightly decreases down toward the trench sidewalls and the TG channel implantation is non-uniform versus the substrate depth. On the other hand, the doping reduction of the active corner can impact both PG and TG channel conduction. Therefore, all these contributions can enable a Vt shift for the TGT transistors compared to the SGT transistor.

B. Discussions

Table II provides a comparison of the three MGT architectures with respect to the planar SGT transistor. Three device parameters are considered: the ION current, the Ss and the area. Moreover, we consider two figures of merits for the multi-gate architectures: the ION/IOFF and ION/Area ratios. We can see in Table II a driving capability enhancement of about 96% for the DGT architecture and roughly 220% for both TGT architectures with respect to the SGT one. Regarding the Ss parameter, we observe that for the DGT, a 11% decrease is reported and for the TGT1 and TGT2, a 26% and 49% decrease are reported respectively. Concerning the area, all the MGT structures have a larger footprint than the SGT one. Two trenches integration leads to a 36% increase of the area for the TGT1 architecture and a 23% increase for the TGT2. However, the one trench integration (DGT architecture) results in a lower increase of only 8% compared to the SGT one. According to the ION/IOFF figure of merit, the two TGT structures show a degradation of this parameter with a 84% and 92% decrease. However, the DGT architecture shows a strong improvement of the ION/IOFF ratio by 96% with respect to the SGT architecture. Finally, the Ion/Area ratio increases versus the number of integrated trenches with an optimal value for the TGT2 architecture.

IV. CONCLUSION

We have investigated the electrical behavior of three different architectures of a novel multi-gate transistor. The MGT is made of distinct conduction channels controlled by independent gates (PG and TG). Different MGT architectures have been manufactured with single and double trench integration (DGT, TGT1 and TGT2). Experimental results demonstrate the functionality of the MGT architectures. Moreover, the performances of the MGT architectures are compared to a regular planar transistor based on ION, IOFF, Ss, area and two figures of merit which are ION/IOFF and ION/Area ratios. Experimental results demonstrate optimal performances for the Dual Gate Transistor architecture (DGT) with improvements of 96% for the driving capability, 11% decrease of Ss, 96% for the ION/IOFF ratio and finally 81% for the ION/Area ratio, making it ideal for analog applications requiring high driving capability as well as low power applications due to its high ION/IOFF ratio.

Fig. 2 .

 2 Fig. 2. Trenches integration. (a) Initial MOSFET SGT and (b) Triple Gate Transistor. (c) Conduction mode of TGT.

Fig. 1 .

 1 Fig. 1. Trench patterning detailed with (a) STI/Active definition, (b) trench etching and (c) trench filling.

Fig. 4 .

 4 Fig. 4. I-V characteristics in linear and saturated conduction modes in log and linear scales for: (a) SGT, (b) DGT, (c) TGT1 and (d) TGT2.