Time-resolved reflectance difference spectroscopy study of Sb- and As-terminated InP(100) surfaces

Autor: O.J. Pitts, C. X. Wang, Simon P. Watkins
Rok vydání: 2003
Předmět:
Zdroj: Journal of Crystal Growth. 248:259-264
ISSN: 0022-0248
DOI: 10.1016/s0022-0248(02)01921-8
Popis: Using time-resolved reflectance difference spectroscopy (RDS) we studied the formation of Sb and As overlayers on InP(1 0 0) under real-time metalorganic vapour-phase epitaxy conditions at 560°C. Exposure of a clean P-rich InP surface to TBAs vapour caused a (2×4)-like RDS spectrum similar to previous reports for bulk InAs. This (2×4)-like surface evolved to a (4×2)-like In-rich surface with a strong negative minimum at 2.0 eV after a 2 s H 2 purge. The RDS spectrum then recovered very rapidly to the InP(2×4)-like surface after only a few monolayers of InP growth. Exposure of the P-rich InP surface to TMSb vapour resulted in the formation of a new RDS spectrum with a strong negative peak at 1.9 eV and a positive feature at 3.7 eV which is attributed to surface–surface transitions. Sb surface layers were found to be much more stable and persistent than As layers, and RDS data indicate significant Sb after as much as 200 A of subsequent InP growth.
Databáze: OpenAIRE