Comparison of Cl2 and HCl Adsorption on Si(100)-(2x1)
Abstract
The chemisorption and reaction Of Cl2 and HCl on Si(100)-(2xl) have been studied using a variety of measurement methods. At 1OOK, both Cl2 and HCl dissociatively chemisorb on the dangling bonds of Si(100). At saturation coverage, the surface concentration of Cl is about one Cl atom per Si atom while HCl can produce a Cl coverage only one fourth of that achieved with Cl2. This is the first report of a self-site-blocking effect in adsorption on a semiconductor surface. HREEL spectra indicate that both Cl2 and HCl adsorption at 100K give a monochloride surface species with a Si-Cl stretching frequency of approximately 550-600 cm (-1). Digital ESDIAD measurements reveal that the Si-CL bond angle for the monochloride from both Cl2 and HCI adsorption is oriented on the vertical plane containing the Si-Si dimer bond and is inclined from the surface normal. The etching products of Si(100) by Cl2 at elevated temperatures are SiCl2 at approximately 800K and a small amount of SiCl4 at approximately 500K. For HC1, the only observed etching product is SiCl2 Silicon, Halogen, Atomic lazer epitaxy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1992
- Accession Number
- ADA252802
Entities
People
- C. C. Cheng
- J. T. Yates Jr.
- P. J. Chen
- Qing Gao
- Wolfgang J. Wolfgang J. Choyke
Organizations
- University of Pittsburgh