Hillock Formation on (100) GaAs.

For application to the growth of gallium arsenide GaAs by metal-organic chemical vapor deposition, the dependence of surface morphology and hillock formation on crystal orientation, AsH3TMG ratio, and oxide contamination was investigated. Layers of GaAs were deposited on undoped liquid-encapsulated Czochralski LEC GaAs substrates oriented either 100 or 100 2 deg yields 110. Substrate orientation was checked by Laue X-ray diffraction. Surface features were observed by phjase contrast optical microscopy and surface profilometry. To examine the relationship of hillock formation to oxide contamination, GaAs substrate surfaces were exposed to water vapor prior to epitaxial growth. Keywords Gallium arsenide Arsine and Surface defects.