Materials World Network on III-V Bismide Materials for IR and Mid IR Semiconductors Joanna M. Millunchick, University of Michigan Ann Arbor, DMR 0908745.
Materials World Network on III-V Bismide Materials for IR and Mid IR Semiconductors Joanna M. Millunchick, University of Michigan Ann Arbor, DMR 0908745
Semiconductor devices require perfection crystal structure, including abrupt interfaces and homogeneous composition. This project examines how bismuth alters these characteristics.
It is known that bismuth alters the surface on the micrometer scale (see Fig. b and c). We show that this is accomplished by the unintuitive mechanism of roughening on the atomic scale (see Fig. a and c)
The reason for this is that bismuth alters the surface structure (Fig. f and g), thus changes the growth of the film. We calculated the surface phase diagram (Fig. e) using sophistication ab initio calculations and a cluster expansion technique. This diagram not only agrees with experiment, but provides an explanation for compositional non homogeneities in these alloys
After Bi deposition
Adam Duzik, John Thomas, Anton van der Ven, and Joanna M. Millunchick, J. Lång, M.P.J. Punkkinen, and P. Laukkanen, “Surface Structure of Bismuth Terminated GaAs Surfaces Grown with Molecular Beam Epitaxy, Surface Science 606 15 (2012)