Simulation and fabrication of spin-based nanoelectronic devices
Abstract
Power dissipation in electronic devices is believed to be the single most important issue that prevents the further downscaling and the performance enhancement of the charge based CMOS devices. Spin based devices are currently being explored as a potential beyond-CMOS computing technologies with lower power dissipation and higher performance. The objectives of this thesis are 1) to understand the performance of the traditional spin field-effect transistor (spinFET) with a quantum mechanical simulation, 2) to evaluate the newly proposed All-Spin Logic (ASL) device and review the key experiments, 3) to optimize the key component (channel) of ASL and try to fabricate the first-level ASL devices, and 4) to propose and fabricate the initial Giant Spin Hall Effect devices. We first study the spin-dependent quantum transport for spinFET using a numerical simulation which includes the effect of both spin scattering in the channel and the tunneling transport across the barriers between the source/drain and the channel, and find the key parameters to enhance the devices performance. The simulation results are benchmarked against the experiments to validate our model. Then a more energy-efficient device, the ASL, is discussed, and the key experiments demonstrating the feasibility of different components of the ASL devices are reviewed. We start to fabricate the ASL devices on graphene by showing the initial realization of the "read-out" function through the non-local lateral spin valve effect, and the optimization of the spin relaxation length to promote the performance of the devices. In order to study the device, the spin circuit model of the ASL device has to be understood to guide the experiment design. Finally a new type of Giant Spin Hall Effect device is proposed and we analyze the switching capability of these devices through both calculation and the initial fabrication.^
Degree
Ph.D.
Advisors
Joerg Appenzeller, Purdue University, Mark S. Lundstrom, Purdue University.
Subject Area
Nanotechnology
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.