A SCANNING-TUNNELING-MICROSCOPY STUDY OF EPITAXIAL GE GROWTH

We report new findings on Ge homoepitaxy on the (110) face using molec ular beam epitaxy techniques. Our in-situ scanning tunneling microscop y study reveals that low temperature growth (T similar to 300 degrees C) followed by annealing ed by annealing at T similar to 500 degrees C produces superior surface morphology with long terraces (> 1 mu m). H igh temperature growth (T > 500 degrees C), on the other hand, promote s the formation of facets and pits. A roughening transition occurs for growth th temperatures < 300 degrees C, where long and regularly spac ed ridges form along the [1 ($) over bar 10] direction.