SI(111)-(7X7) UNDER SILANE UHV-LPCVD - A STM STUDY

In this work, we present a scanning tunneling microscopy (STM) study o f the LPCVD (low pressure chemical vapor deposition) growth of Si on S i(111)-(7 x 7) using silane (SiH4) decomposition. Surface reactivities have been studied at room and high temperature (700 < T < 800 K), and the major chemical mechanisms have been identified at an atomic scale on the basis of room temperature STM images of the reacted surfaces. The study provides a better understanding of nucleation and initial st ages of growth. More particularly, we show that the growth kinetics an d the final structure of the film are different from what is observed by molecular beam epitaxial (MBE) growth.