Several Specifics of Silicon Atom Condensation on the Surface of a Tungsten Single Crystal

Abstract

Field emission microscopy was used to study Si condensation on a W surface by varying substrate temperature T and number n of monoatomic layers of the precipitated condensate. A low-temperature Si monolayer with a pure W structure formed at lower temperatures of T ~ 600 K, while another structure of a high-temperature surface silicide monolayer formed at T ≥ 1000 K. The orienting effect additionally differed between the low-temperature monolayer and surface silicide during further growth of Si layers. Pure Si crystallites formed starting from the third monolayer (n ≥ 3) in the case of condensation on the low-temperature monolayer and starting from n ≥ 300 monolayers in the case of condensation on surface silicide. Estimates were obtained for the activation energy Qdif of Si diffusion into the W lattice and the desorption energy Qdes of Si atoms from the W surface.