Charge collection microscopy of annealing induced electrically active defects in Si1−xGex/Si strained layer epitaxy

Abstract

Images of electrically active defects in Si1−xGex strained epilayers onn-type Si(100) have been obtained using charge collection microscopy (CCM) in a scanning electron microscope. Electrically active defects were generated in the defect-free as-grown material by rapid thermal annealing treatments (3 min) over a temperature range of 550 to 850° C. Point-like contrast, attributed to threading dislocations, as well as an additional line contrast due to the formation of an interface misfit dislocation network, were observed as the metastable strained Si1−xGrx layers relaxed upon annealing. Cross-sectional and plan-view transmission electron microscopy were used to examine the Si1−xGex epilayers in finer detail. Double crystal x-ray diffraction and Raman scattering spectra were also obtained and the annealing induced peak shifts investigated.