Dislocation-Free Fully Relaxed SiGe Substrate

Mon, 16 Mar 2009 14:48:08 -0500

Left: Atomic force microscope (AFM) scan of SiGe fabricated by the conventional technique. Root mean square (RMS) roughness is 13 nm. The crosshatch is a sign of severe dislocation formation. Right: AFM scan of our SiGe substrate. RMS roughness = 0.27 nm.

[Image378]B. Tanto, D. E. Savage, M. G. Lagally (DMR #0520527)To make modulation-doped 2-dimensional electron-gas structures for applications in quantum electronics, the requirements on the quality and strain state of the materials for the Si/SiGe heterojunctions are extremely stringent. Defect-free strained silicon and silicon/germanium alloy will be ideal. Such perfect materials currently do not exist. We have developed a new process for fabricating defect-free strained-Si-based....

Electronically Driven Structure Changes of Si Captured by Femtosecond Electron Diffraction

Mon, 16 Mar 2009 14:38:51 -0500

[Image379]Max Lagally, Robert Blick, Irenz Knezevic, Zhenqiang Ma, Mark Eriksson (DMR #0520527)Members of IRG1 worked with a research group at the University of Toronto Canada to provide Si nanomembranes that enabled a unique experiment to be accomplished. The research group of Dwayne Miller, Institute for Optical Sciences and Departments of Physics and Chemistry, University of Toronto has singular capabilities for femtosecond electron diffraction to measure really fast electronic....

UW MRSEC IRG 1 Nuggets

Dislocation-Free Fully Relaxed SiGe Substrate

Electronically Driven Structure Changes of Si Captured by Femtosecond Electron Diffraction