Formation of selective epitaxially grown silicon with a flat edge by ultra-high vacuum chemical vapor deposition

We studied the dependence of selective epitaxially grown silicon (SEG-Si) s hape on the conditions of ultra-high vacuum chemical vapor deposition using disilane (Si2H6) gas, which grew on Si (100) substrates patterned with SiO 2 stripes. SEG-Si edges typically formed two types of configurations: facet s and bumps. It was confirmed that the shape of SEG-Si edge is strongly dep endent on the growth mode of the (100) plane: facet configurations are form ed in the mass transfer limited region, and bump configurations are formed in the kinetically limited region. Therefore, it was concluded that the sur face migration length of adatoms resulting from the decomposition of Si2H6 molecules is related to the formation of the shape of the SEG-Si. Moreover, it was confirmed that the flat shape of the SEG-Si is obtained by adjustin g both the Si2H6 flow rates and the growth temperature. (C) 2001 Elsevier S cience B.V. All rights reserved.