Bandstructure Effects in Nano Devices&Examples Using NEMO5

As semiconductor device and circuit engineers we traditionally think of band edges and effective masses as fixed fundamental material parameters. However, at nanometer device lengths these two parameters can be modified by design. New materials and geometries enter the design space to control these parameters and improve device performance. An atomistic representation of the underlying materials enables a fundamental (and fast) numerical evaluation of these bandstructure effects. Beyond the bandstructure, we can no longer think of the electrons & holes to be classical particles or densities and furthermore they cannot be considered to be in a local equilibrium. Over the past 25 years a new device modeling approach and technology entitled Nanoelectronic Modeling (NEMO). NEMO established the Non-Equilibrium Greens Function Formalism (NEGF) and atomistic tight-binding as today’s state-of-the-art in device modeling. The NEMO research and development has always been coupled to experimental device validation. This presentation will intuitively describe how bandstructure is modified at the nanometer scale and what some of the consequences are on the device performance.

What attendees will learn:

• How non-parabolic bandstructure affects quantization and tunneling
• How effective masses and bandedges depend on nanowire shapes and crystal directions
• How non-equilibrium transport at the top of the barrier influences transistor design
• How leakage current can be designed through crystal directions

Presenter

Gerhard Klimeck is the Reilly Director of the Center for Predictive Materials and Devices (c-PRIMED) and the Network for Computational Nanotechnology (NCN) and a Professor of Electrical and Computer Engineering at Purdue University. He guides the technical developments and strategies of nanoHUB.org which annually serves over 1.4 million visitors worldwide with on-line simulation, tutorials, and seminars. He was previously with NASA/JPL and Texas Instruments leading the Nanoelectronic Modeling Tool development (NEMO). His work is documented in over 500 peer-reviewed journal and proceedings articles resulting in over 15,000 citations and a citation h-index of 60 on Google Scholar. He is a fellow of the IEEE, American Physical Society, and the Institute of Physics.