REM studies of the roughening transitions of Si high index surfaces

We carried out in situ REM-RHEED (reflection electron microscopy-reflection high-energy electron diffraction) observations of the inner cylindrical Si surfaces to study surface structural phase transitions on various high ind ex surfaces in the UHV condition. We observed reversible structural phase t ransitions that were suggested to be the roughening transitions on the high index surfaces. The transition temperatures are about 1000 degrees C, 880 degrees C, 780 degrees C, 805 degrees C, 820 degrees C and 770 degrees C fo r the (119), the (117), the (114), the (331), the (551) and the (320) surfa ces, respectively. The results on the (119), the (117) and the (114) surfac es indicated that the roughening transition temper-ature decreases monotono usly with increasing off- angles from the (001) orientation. (C) 1999 Elsev ier Science S.A. All rights reserved.