Influence of Surface Defects on Chlorine Chemisorption on Si(100)-(2 x 1).
Abstract
The influence on chlorine chemisorption of surface defects created by low fluence Ar(+) sputtering of the Si(100)-(2x1) surface has been studied. A distinctly different type of Cl bonding is observed on defect sites compared to Cl bonding on Si-Si dimers, as judged by electron stimulated desorption ion angular distribution (ESDIAD) measurements. On the ordered Si(100) surface only terminally bonded Si-Cl species are observed (producing four off-normal Cl(+) beams); on the disordered Si(100) surface an additional Cl(+) beam emitted in the normal direction is present at 120K. This Cl(+) beam is interpreted as a bridge bonded Cl species chemisorbed inside of the dimer vacancy defects. In SiCl2 thermal desorption a new low temperature desorption channel is observed on disordered Si(100) surfaces indicating that defect sites enhance the rate of surface etching. In the range of Ar(+) fluences studied (0.2-5 monolayer) the Cl saturation coverage increases by as much as 30% over that observed on non-defective Si(100)-(2x1).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 12, 1996
- Accession Number
- ADA310552
Entities
People
- J. T. Yates Jr.
- Wenjie Yang
- Wolfgang J. Wolfgang J. Choyke
- Z. Dohnalek
Organizations
- University of Pittsburgh