Date: Thursday 27 March 2014
Time: 08:30 - 10:00
Location / Room: Saal 1

Organisers:
Ian O'Connor, Lyon Institute of Nanotechnology, FR
Thomas Mikolajick, NamLab gGmbH, DE

Chair:
Thomas Mikolajick, NamLab gGmbH, DE

Co-Chair:
Ian O'Connor, Lyon Institute of Nanotechnology, FR

Transistors as switches have now scaled down to a point where the classical bulk structure is no longer tenable and it is necessary to change the nature of the channel structure. In this session, the three principal contenders for following on from conventional devices will be examined. The first paper looks at the use of III-V nanowires, with expected benefits in terms of speed and energy, as well as integration challenges. The second paper looks at how the use of switches with controllable polarity, such as in silicon nanowire devices, can improve the energy efficiency of systems on chip. The devices themselves are explored in detail in the third paper, with the concept of fine-grain reconfigurability at the fore. The fourth and final paper gives a reality check on carbon electronics and the most promising devices in this class.

Time	Label	Presentation Title Authors
08:30	9.1.1	III-V SEMICONDUCTOR NANOWIRES FOR FUTURE DEVICES Speakers: H. Schmid, B. Borg, K. Moselund, P. Das Kunungo, G. Signorello, S. Karg, P. Mensch, V. Schmidt and H. Riel, IBM Research, CH Abstract The monolithic integration of III-V nanowires on silicon by direct epitaxial growth enables new possibilities for the design and fabrication of electronic as well as optoelectronic devices. We demonstrate a new growth technique to directly integrate III-V semiconducting nanowires on silicon using selective area epitaxy within a nanotube template. Thus we achieve small diameter nanowires, controlled doping profiles and sharp heterojunctions essential for future device applications. We experimentally demonstrate vertical tunnel diodes and gate-all-around tunnel FETs based on InAs-Si nanowire heterojunctions. The results indicate the benefits of the InAs-Si material system combining the possibility of achieving high Ion with high Ion/Ioff ratio.
08:50	9.1.2	ADVANCED SYSTEM ON A CHIP DESIGN BASED ON CONTROLLABLE-POLARITY FETS Speakers: Pierre-Emmanuel Gaillardon, Luca Amaru, Jian Zhang and Giovanni De Micheli, Integrated Systems Laboratory – Swiss Federal Institute of Technology, CH Abstract Abstract—Field-Effect Transistors (FETs) with on-line controllable-polarity are promising candidates to support next generation System-on-Chip (SoC). Thanks to their enhanced functionality, controllable-polarity FETs enable a superior design of critical components in a SoC, such as processing units and memories, while also providing native solutions to control power consumption. In this paper, we present the efficient design of a SoC core with controllable-polarity FET. Processing units are speeded-up at the datapath level, as arithmetic operations require fewer physical resources than in standard CMOS. Power consumption is decreased via embedded power-gating techniques and tunable high-performance/low-power devices operation. Memory cells are made smaller by merging the access interface with the storage circuitry. We foresee the advantages deriving from these techniques, by evaluating their impact on the design of SoC for a contemporary telecommunication application. Using a 22-nm vertically-stacked silicon nanowire technology, we estimate a delay and power reduction of 20% and 19% respectively, at a cost of a moderate area overhead of 15%, with respect to a state-of-art FinFET technology.
09:15	9.1.3	RECONFIGURABLE SILICON NANOWIRE DEVICES AND CIRCUITS: OPPORTUNITIES AND CHALLENGES Speakers: Walter Weber1, André Heinzig2, Jens Trommer1, Markus König2, Matthias Grube1 and Thomas Mikolajick1 1Namlab gGmbH, DE; 2Technische Universität Dresden, DE Abstract Reconfigurable fine-grain electronics target an increase in the number of integrated logic functions per chip by enhancing the functionality at the device level and by implementing a compact and technologically simple hardware platform. Here we study a promising realization approach by employing reconfigurable nanowire transistors (RFETs) as the multifunctional building-blocks to be integrated therein. RFETs merge the electrical characteristics of unipolar n- and p- type FETs into a single universal device. The switch comprises four terminals, where three of them act as the conventional FET electrodes and the fourth acts as an electric select signal to dynamically program the desired switch type. The transistor consists of two independent charge carrier injection valves as represented by two gated Schottky junctions integrated within an intrinsic silicon nanowire. Radial compressive strain applied to the channel is used as a scalable method to adjust n- and p-FET currents to each other, thereby enabling complementary logic circuits. Simple but relevant examples for the reconfiguration of complete gates will be given, demonstrating the potential of this technology.
09:35	9.1.4	ADVANCING CMOS WITH CARBON ELECTRONICS Speaker: Franz Kreupl, TU Munich, DE Abstract A fresh look on carbon-based transistor channel materials like single-walled carbon nanotubes (CNT) and graphene nanoribbons (GNR) in future electronic applications is given. Although theoretical predictions initially promised that GNR (which do have a bandgap) would perform equally well as transistors based on CNTs, experimental evidence for the well-behaved transistor action is missing up to now. Possible reasons for the shortcomings as well as possible solutions to overcome the performance gap will be addressed. In contrast to GNR, short channel CNT field effect transistors (FET) demonstrate in the experimental realization almost ideal transistor characteristics down to very low bias voltages. Therefore, CNT-FETs are clear frontrunners in the search of a future CMOS switch, that will enable further voltage and gate length scaling. Essential features which distinguish CNT-FETs from alternative solution will be discussed and benchmarked. Finally, the gap to industrial wafer-level scale SWCNT integration will be addressed and strategies for achieving highly aligned carbon nanotube fabrics will be discussed. Without such a high yield wafer-scale integration, SWCNT circuits will be an illusional dream.
10:00		End of session Coffee Break in Exhibition Area On Tuesday-Thursday the coffee and lunch breaks will be located in the Exhibition Area (Terrace Level).