On the Performance of Single-Gated Ultrathin-Body SOI Schottky-Barrier MOSFETs

The authors study the dependence of the performance of silicon-on-insulator (SOI) Schottky-barrier (SB) MOSFETs on the SOI body thickness and show a performance improvement for decreasing SOI thickness. The inverse subthreshold slopes S extracted from the experiments are compared with simulations and an analytical approximation. Excellent agreement between experiment, simulation, and analytical approximation is found, which shows that S scales approximately as the square root of the gate oxide and the SOI thickness. In addition, the authors study the impact of the SOI thickness on the variation of the threshold voltage V-th of SOI SB-MOSFETs and find a non-monotonic behavior of V-th. The results show that to avoid large threshold voltage variations and achieve high-performance devices, the gate oxide thickness should be as small as possible, and the SOI thickness should be similar to 3 nm

Transparenz und Kommunikation der Europäischen Union im Lichte von Art 15 AEUV

Politische, wirtschaftliche und gesellschaftliche Transparenz ist sowohl auf nationaler und supranationaler als auch internationaler Ebene für das Funktionieren der pluralistisch-liberalen Demokratie von größter Wichtigkeit. Rechtliche Entscheidungen, Verwaltungsprozesse und politische Entwicklungen müssen einsichtbar sein. Direkt verbunden damit ist die Notwendigkeit offener politischer Kommunikation. Versperrt man den Informationszugang oder vertritt eine Politik der Geheimhaltung, wird Misstrauen erzeugt und die Entfremdung zwischen dem Bürger und der Verwaltung gesteigert. Die Europäische Union hat beim Knüpfen des Kommunikationsnetzes zweifelsohne Fehler gemacht, die auch zur sinkenden Beliebtheit des institutionalisierten Europa beigetragen haben, was gerade nach der großen Europamotivation der Jahrzehnte davor besonders ins Auge springt. Nun muss sich die EU mit starker Kommunikation neu aufstellen, um eine neue europäische Öffentlichkeit mitzuerschaffen. Das erste Kapitel der Arbeit „Kommunikation und Öffentlichkeit im Wandel der Zeit“ modelliert eine Semantik des Begriffs Kommunikation, gibt mit der Dokumentation von „Flashlights“ der Kommunikationsgeschichte das vielfältige und beeindruckende Bild dieser Entwicklungen wieder, beschreibt die Facetten der Staatskommunikation und schafft mit einer Beurteilung der Kommunikation in der Moderne und der Mediengesellschaft einen Ausblick in die Zukunft. Das zweite Kapitel widmet sich dem Kernthema „Transparenz in der Europäischen Union“. Ein kurzer geschichtlicher Abriss bereitet in Kombination mit der Analyse von Geheimnisschutz, Demokratie und Rechtsstaatlichkeit sowie Öffentlichkeitserfordernissen des Rechtsstaates das Thema auf und führt zum Verständnis der Positivierungen der Transparenzregeln und rechtlichen Regelungsebenen der Transparenz in den Institutionen der Europäischen Union. Im dritten Kapitel wird das „Transparenzgebot als europäischer Rechtsgrundsatz: Art 15 AEUV“ definiert. Mit Art 255 EGV war schon davor eine bahnbrechende Rechtsentwicklung gegeben, die mit der Implementierung in die Vertragsgrundsätze von Lissabon als Nummer 15 unter den ersten zwanzig Artikeln einen auffallenden Transparenzhöhepunkt schuf. Dokumentenzugang ist das wesentlichste Element der Verwaltungsoffenheit. Begriffe, Grundsätze, Verfahren und Ausnahmen müssen dementsprechend rechtsdogmatisch analysiert und rechtspolitisch bewertet werden. Juristische Wegbegleiter für die Transparenz der Europäischen Union waren die Entscheidungen der europäischen Gerichte, von denen exemplarisch im vierten Kapitel „Judikatur“ die wichtigsten Fälle beleuchtet und bewertet werden. Obwohl auch einer maßvollen Vertraulichkeit, vor allem in heiklen Verfahrensstadien, Raum gegeben wurde, hatten die meisten Urteile wesentlich zur Pro-Transparenz-Entwicklung beigetragen und viele Tore mit der Kraft nüchterner Rechtsprechung aufgestoßen oder offen gehalten. Diese Dissertation behandelt in ihrem fünften Kapitel als zweites wichtiges Thema neben der Transparenz die „Kommunikation und Öffentlichkeitsarbeit der Europäischen Kommission“, die gemeinsam mit der proaktiven Seite der Transparenz das Duo einer aufgeschlossenen europäischen Öffentlichkeit bildet. Die EU sieht sich ja mit ihren Organen mit zahlreichen Problemen konfrontiert, denen der Versuch der dezidierten Umsetzung von Öffentlichkeitsarbeit unter partieller Federführung der Generaldirektion Kommunikation gegenübersteht. Zahlreiche in dieser Arbeit analysierte Mitteilungen, Pläne und Initiativen der Kommission dokumentieren dieses Bemühen. Das sechste und letzte Kapitel „Europäische Öffentlichkeit: Analyse und Reformvorschläge im Lichte von Art 15 AEUV“ formuliert die Gesamtbewertung und den Zukunftsblick mit neuen Ideen: Transparent Governance als Teil von Good Governance, eine sinnvolle Symbiose von Öffentlichkeit und Geheimnisschutz, keine Parallelwelten durch Transparenzvorschriften, Transparenz als Bürgerpartizipation und offene Begegnung zwischen Bevölkerung und Verwaltung, noch klarere Regeln für den Dokumentenzugang und die scharfe Eingrenzung von Ausnahmen, schließlich einen „Transparent Governance Codex“ und Bürgerselbstbewusstsein durch Transparenz. Meine Erkenntnisse bündle ich zu einem „Plan E“, einer Europäischen Öffentlichkeit durch integrierte Kommunikation und „Transparent Governance“: Pro-aktiv, institutionell verankert und durchsetzbar, regionalisiert und doch europäisch, unter Einbeziehung klassischer und neuer Medien sowie einer Umsetzung durch eine Reformoffensive mit politischem und rechtlichem Gestaltungswillen. Zuhören, Kommunizieren, Regionalisieren, Europäisieren sind die vier Säulen einer neuen europäischen Öffentlichkeit.Political, economic and social transparency is, both at the national, supranational and international level, of highest importance for the functioning of a pluralistic-liberal democracy. Legal decisions, administrative processes and political developments must be transparent. Directly connected with this fact is the need for open political communication. If access to information is blocked or a policy of secrecy is pursued, distrust will be created together with the estrangement of citizens and the administration. Regarding communication, the European Union has without doubt made mistakes, which also led to a decreasing popularity of the institutional Europe. This is particularly striking when viewed against the backdrop of high European motivation in previous decades. The EU has to position itself anew with strong communication to build a new European public sphere. The first chapter of the paper “Communication and Publicity in changing times“ defines semantics of the term “communication” and illustrates this with “flashlights“ of communication history. The multifarious and impressive image of these developments describes the facets of communication of States and offers a future prospect on communication in modern times and the media society. The second chapter dedicates itself to the core topic “Transparency in the European Union“. A brief historical summary introduces the topic in combination with an analysis of the protection of confidential information, democracy and the rule of law and the need for publicity for the State, with a view to making the various types of transparency rules and regulatory framework in the institutions of the EU understandable. The third chapter is dedicated to the “Transparency requirement as a European legal principle: Art 15 TFEU“. Prior to the entry into force of the Lisbon Treaty (Treaty on the functioning of the European Union, TFEU) there was the groundbreaking legal development with Art 255 TEC (Treaty establishing the European Community), which accomplished an outstanding transparency milestone through the implementation of Art 15 under the first twenty articles of the principles of the TFEU. Access to documents is the most important element of administrative openness. Definitions, terms, principles, procedures and exceptions have to be analysed according to legal doctrine and interpreted in view of legal policy. Judicial drivers for the transparency of the European Union were the decisions of the European courts. Through examples in the fourth chapter “Jurisdiction“ the most important cases are highlighted and evaluated. Although there was space given to moderate confidentiality, especially in delicate stages of procedure, most judgements contributed to the development of pro-transparency and opened many doors with the strength of pragmatic decision making. This dissertation deals in its fifth chapter with the second important topic besides transparency “Communication and public relations of the European Commission“, which contributes with the pro-active side of transparency to an open-minded European public sphere. The EU with its institutions is confronted with many problems, and is faced with the need to realise solid public relations work under the partial leadership of the Directorate General Communications. Various action plans are analysed and initiatives of the Commission document this effort. The sixth and last chapter “European public: Analysis and proposals for reforms on the basis of Art 15 TFEU“ gives an overall evaluation and looks to the future with new ideas: Transparent governance as part of good governance, a reasonable symbiosis of public and confidential information, no parallel existence through exaggerated transparency regulations, transparency as civic participation and open-minded interaction between civil society and administration, even more clear regulations for the access of documents and carefully selected exceptions, finally a “Transparent Governance Codex“ and self-confidence of citizens through transparency. My findings are brought together into a “Plan E“, a European public domain founded on integrated communications and “Transparent Governance“: pro-active, institutionally and politically anchored, regional but at the same time European, involving classical and new media, and the implementation of a reform offensive with political and judicial emphasis on design and creation. Listening, communicating, regionalising, Europeanising are the four pillars of strength of a new European public sphere

Evaluating intuitive decision-making in non-metric sex estimation from the cranium: an exploratory study

In recent years, forensic science has seen a rise in the number of multidisciplinary studies examining the effect of human cognition on the evaluation of forensic evidence. Notably, the House of Lords’ report highlighted the need for further investigation of the consequences of cognitive factors on decision-making processes involved in evidence evaluation and interpretation. Utilizing the concepts of intuitive and methodical decision-making, this pilot study investigated this dichotomy within the field of forensic anthropology, applied to sex estimation from the skull. Participants were asked to estimate the biological sex of six crania in two experiments: once ‘intuitively’ under time-pressure, and once by rationally applying the Acsádi and Nemeskéri method with no time-pressure. The potential influence of experience and its correlation with the participants’ confidence levels was also explored. The results demonstrate that intuitive and methodical evaluations can be consistent with each other, yet consistency decreases as ambiguity increases. Confidence was affected more by time availability, and less by level of experience. The insights from this exploratory study address how decision-making processes are involved in the examination of skeletal remains and offers justification for future exploration into the value of applying wider decision-making theories in the field of forensic anthropology

Fabrication of epitaxial CoSi₂ nanowires

We have developed a method for fabricatingepitaxialCoSi₂nanowires using only conventional optical lithography and standard silicon processing steps. This method was successfully applied to ultrathin epitaxialCoSi₂ layers grown on Si(100) and silicon-on-insulator substrates. A nitride mask induces a stress field near its edges into the CoSi₂/Siheterostructure and leads to the separation of the CoSi₂ layer in this region during a rapid thermal oxidation step. A subsequent etching step and a second oxidation generate highly homogenous silicide wires with dimensions down to 50 nm

Nanopatterning of epitaxial CoSi₂ using oxidation in a local stress field and fabrication of nanometer metal-oxide-semiconductor field-effect transistors

A patterning method for the generation of epitaxialCoSi₂nanostructures was developed based on anisotropic diffusion of Co∕Si atoms in a stress field during rapid thermal oxidation (RTO). The stress field is generated along the edge of a mask consisting of a thin SiO₂ layer and a Si₃N₄ layer. During RTO of the masked silicide structure, a well-defined separation of the silicide layer forms along the edge of the mask. The technique was used to make 50-nm channel-length metal-oxide-semiconductor field-effect transistors(MOSFETs). These highly uniform gaps define the channel region of the fabricated device. Two types of MOSFETs have been fabricated: symmetric transistor structures, using the separated silicide layers as Schottky source and drain, and asymmetric transistors, with n+ source and Schottky drain. The asymmetric transistors were fabricated by an ion implantation into the unprotected CoSi₂ layer and a subsequent out diffusion to form the n+ source. The detailed fabrication process as well as the I–V characteristics of both the symmetric and asymmetric transistor structures will be presented

Scanning spreading resistance microscopy of two-dimensional diffusion of boron implanted in free-standing silicon nanostructures

B implants of 1keV, 1×10¹⁵at.cm⁻² into 125-nm-wide, free-standing Si nanostructures have been characterized using scanning spreading resistancemicroscopy following a 0s, 1050°Canneal in N₂. A curved diffusion front has been observed. B in the center of the ridge diffuses further than at the sides. A similar effect has been observed in SUPREM-IV simulations. It is attributed to a reduction in transient enhanced diffusion close to the vertical surfaces due to recombination of ion-implantation-induced excess Si self-interstitials

Impact of TFET unidirectionality and ambipolarity on the performance of 6T SRAM cells

We use mixed device-circuit simulations to predict the performance of 6T static RAM (SRAM) cells implemented with tunnel-FETs (TFETs). Idealized template devices are used to assess the impact of device unidirectionality, which is inherent to TFETs and identify the most promising configuration for the access transistors. The same template devices are used to investigate the $ extV- m DD range, where TFETs may be advantageous compared to conventional CMOS. The impact of device ambipolarity on SRAM operation is also analyzed. Realistic device templates extracted from experimental data of fabricated state-of-the-art silicon pTFET are then used to estimate the performance gap between the simulation of idealized TFETs and the best experimental implementations

Detrmination of the parameters of the ground state of C2H3D molecule

Present study dedicated to analysis of C2H3D molecule spectra and determination of the parameters of the ground vibrational state of the molecule. In total, positions of more than 10000 transitions were determined. 1037 ground state combination differences were used to improve ground state parameters of the molecule

Strained Silicon Complementary TFET SRAM: Experimental Demonstration and Simulations

A half SRAM cell with strained Si nanowire complementary tunnel-FETs (TFETs) was fabricated and characterized to explore the feasibility and functionality of 6T-SRAM based on TFETs. Outward-faced n-TFETs are used as access-transistors. Static measurements were performed to determine the SRAM butterfly curves, allowing the assessment of cell functionality and stability. The forward p-i-n leakage of the access-transistor at certain bias configurations leads to malfunctioning storage operation, even without the contribution of the ambipolar behavior. At large VDD, lowering of the bit-line bias is needed to mitigate such effect, demonstrating functional hold, read and write operations. Circuit simulations were carried out using a Verilog-A compact model calibrated on the experimental TFETs, providing a better understanding of the TFET SRAM operation at different supply voltages and for different cell sizing and giving an estimate of the dynamic performance of the cell

Optical Transitions in Direct-Bandgap Ge1-xSnx Alloys

A comprehensive study of optical transitions in direct-bandgap Ge0.875Sn0.125 group IV alloys via photoluminescence measurements as a function of temperature, compressive strain and excitation power is performed. The analysis of the integrated emission intensities reveals a strain-dependent indirect-to-direct bandgap transition, in good agreement with band structure calculations based on the 8-band k·p and deformation potential methods. We have observed and quantified Γ valley-heavy hole and Γ valley-light hole transitions at low pumping power and low temperatures in order to verify the splitting of the valence band due to strain. We will demonstrate that the intensity evolution of these transitions supports the conclusion about the fundamental direct bandgap in compressively strained GeSn alloys. The presented investigation, thus, demonstrates that direct-bandgap group IV alloys can be directly grown on Ge-buffered Si(001) substrates despite their residual compressive strain