Surface Studies of Bi on GaAs Joanna M. Millunchick , University of Michigan, DMR 0908745

1. Surface Studies of Bi on GaAsJoanna M. Millunchick, University of Michigan, DMR 0908745 The addition of small amounts of Bi into GaAs results in a large reduction in the bandgap energy and a significantly broader spectrum. Because of the challenge incorporating Bi into the growing film, controlling surfaces is key to controlling interface quality in III-V device growth. Scanning Tunneling Micrographs of submonolayer amounts of Bi on GaAs show radical changes in the surface structure, including clustering and changes in the atomic surface structure. These results indicate the path by which inhomogeneous Bi composition variations observed by other methods are possible. ~0.6 ML Bi on GaAs (001) RHEED pattern along the (a) [110] and (b) [-110]. (c) 50x50 nm STM image (V=-3.00 V, I=0.1 nA) of the (001) surface. Bi induces both morphological changes (clustering and pitting) and atomic surface structure changes.

2. 1st International Workshop on Bi-Containing Semiconductors Joanna M. Millunchick, University of Michigan, DMR 0908745DMR 0908745 & 0909028 43 researchers from all over North America, Europe, Asia, and Australia converged on the University of Michigan in Ann Arbor July 13-16, 2010 for the first International Workshop on Bi-containing Semiconductors sponsored jointly by the National Science Foundation and the Michigan Center on Theoretical Physics. Technical talks included topics on: Bismide growth and bismuth incorporation strategies Structural, electrical, and optical characterization Theoretical studies of bismide semiconductor properties and device physics Device fabrication and performance The small size of the workshop and thoughtful social activities resulted in many fruitful discussions, and nucleated new scientific interactions.