In situ TEM observations of surface roughening and defect formation in lattice-mismatched, heteroepitaxial thin films

摘要

This paper focuses on in-situ transmission electron microscopy observations of surface roughening and defect formation in heteroepitaxial Si_(1-x)Ge_x thin films. Annealing experiments have been carried out in-situ in the microscope under a high vacuum environment. We comment on the sample preparation procedure for in-situ TEM experiments and explain the importance of having a sufficiently thick sample to have the stress state in the film unaltered. Experimental results of in-situ surface roughening are presented for subcritically and supercritically thick Si_(1-x)Ge_x films. We found that, in a vacuum environment, the kinetics of surface roughening and the resulting surface morphology are much different than in a hydrogen environment.