Chemistry of Hydrogen on Diamond (100)
Abstract
Hydrogen plays a crucial role in diamond film growth by chemical vapor deposition and is likely to be similarly critical to atomic layer epitaxy, yet the surface chemistry of hydrogen on diamond is only beginning to be understood. We have investigated the adsorption of hydrogen and deuterium on diamond (100) by temperature-programmed desorption and by infrared multiple-internal-reflection spectroscopy using a natural type IIa diamond internal reflection element. Complementary theoretical studies have been carried out using the empirical MM3 molecular mechanics force field, which has a demonstrated high degree of accuracy for many molecules despite computational simplicity. H2 desorption was observed with a peak temperature of =1250 K and a peak shape suggestive of first-order kinetics. Assuming a preexponential factor of 10(13) sec-1, the activation energy for desorption is estimated as =80 kcal/mol. Infrared evidence was seen for the monohydride surface structure, with one hydrogen atom per surface carbon atom (curlydCD mode at 901 cm-1). The MM3 calculations predict that the (2xl):H monohydride phase is the most stable thermodynamically and the dominant phase under typical chemical vapor deposition conditions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 29, 1992
- Accession Number
- ADA252874
Entities
People
- L. F. Sutcu
- L. M. Ulvick
- M. P. D'evelyn
- Y. L. Yang
Organizations
- Rice University