The Adsorption and Thermal Decomposition of PH3 on Si(111)-(7x7)
Abstract
The adsorption of PH3 (Phosphine) on Silicon(111)-(7x7) has been studied by Auger electron spectroscopy and temperature programmed desorption. PH3 was found to exhibit two kinds of behavior on the surface. A small surface coverage of molecularly adsorbed PH3 desorbs without and dissociative surface chemistry. For the majority of the adsorbed, PHx species (3>x>1) dissociation occurs to form P(a) and H(a). At 120 K, PH3 initially adsorbs as the reactive species with a sticking coefficient of S approx. 1 up to approx. 75% saturation. Capping the Si-dangling bonds with atomic deuterium prevents PH3 adsorption, indicating that the dangling bonds are the PH3 adsorption sites. Isotopic studies involving Si-D surface species mixed with adsorbed PHx species indicate that PH3 desorption does not occur through a recombination process. Finally, additional PH3 may be adsorbed if the surface hydrogen produced by dissociation of PH3 is removed. Keywords: Si(111), PH3, Phosphine, Phosphorus, Hydrogen phosphide, Silicon, Surface chemistry, Desorption, Dissociation, Doping.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 18, 1990
- Accession Number
- ADA222417
Entities
People
- J. T. Yates Jr.
- P. A. Taylor
- R. M. Wallace
- Wolfgang J. Wolfgang J. Choyke
Organizations
- University of Pittsburgh