SURFACE-MORPHOLOGY OF EPITAXIAL GE ON SI GROWN BY PLASMA ENHANCED CHEMICAL VAPOR-DEPOSITION

Heteroepitaxial Ge films have been deposited on (100) Si substrates at low temperature (325-degrees-C) by electron cyclotron resonance plasma enhanced chemical vapor deposition. The substrates were subjected to an in situ hydrogen/argon plasma etch prior to film growth to remove carbon and oxygen. The surface morphology has been observed with optical and scanning electron and scanning tunneling microscopy. Surface roughness due to three dimensional growth is strongly influenced by ion flux and arrival rate of reactive species on the growth surface. Surface roughness has a detrimental effect on the crystallinity of the deposited films as determined by reflection high-energy electron diffraction and x-ray diffraction measurements.