Research

The Lundstrom Group is currently involved in the following major research programs:

The Network for Computational Nanotechnology (link)

Focus Center on Materials, Structurs, and Devices (link)

Nanoelectronics Research Initiative (link)

Thermoelectric and Thermionic Energy Conversion/Cooling Devices

Overview of our current research:

III-V MOSFETs

As predicted by the International Roadmap for Semiconductors (ITRS), power consumption has been the bottleneck for future silicon CMOS technology scaling. To circumvent this limit, researchers are investigating alternative structures and materials, among which III-V compound semiconductor based quantum-well field effect transistors stand out as one of the most promising device candidates for future high-speed, low-power digital logic applications, because their light effective masses lead to high electron mobility and high on-current, which should translate into high device performance at low supply voltage. For such nanoscale devices, both atomistic and quantum effects become important in determining their electronic structure and transport properties. Detailed modeling and simulation that capture these effects will be essential to help understand and provide guidance to the device operation and optimization for future post-Si CMOS. The research on III-V nanoscale transistors carried out in our group includes simulation and analysis of III-V HEMTs and MOSFETs for low-power high-speed logic applications, Schottky barrier III-V MOSFETs, C-V analysis of experimental data on III-V MOS capacitors and transistors, bandstructure effects of III-V’s and parasitic series resistance of III-V HEMTs.

 

Nanowires

Trends in Silicon scaling of planar MOSFETs is fast approaching the size limit of what is possible. In order to continue the current trends in scaling of integrated circuit technology, nanowires have shown promise as a future tool for new novel devices including high performance transistors, flexible electronics, sensing apparatus, thermoelectric and photovoltaic applications. Nanowire applications are rapidly growing, and the need for fundamental understanding of the device physics is paramount. Our research strives to meet this growing demand by matching experimental results to simulation results, and develop an understanding of the electrostatics behind nanowire devices.

Thermoelectrics

Thermoelectric (TE) devices act to either convert heat to electricity (power generation) or pump heat from cold to hot (active cooling, refrigeration).  TE power generation can be utilized in recovery of waste heat in computing, engines, and other sources of otherwise unused heat.  TE cooling can be applied where active cooling is needed such as removing heat from hot spots in on-chip cooling. Although TE devices are clean and reliable, their applications have been limited due to the low efficiency, which is represented by the figure of merit, ZT. Recent advancements in engineering nanostructures have made it possible to increase ZT significantly. Our goal is to understand the TE device physics, develop theoretical models and provide simulation capabilities both in the device and system levels, and finally give some guidance on the improved designs of TE devices.