AVS 45th International Symposium
    Surface Science Division Wednesday Sessions
       Session SS2-WeA

Paper SS2-WeA8
Interaction of Amines with Hydrogen on Al(111)

Wednesday, November 4, 1998, 4:20 pm, Room 309

Session: Photochemistry and Deposition
Presenter: J.N. Russell, Jr., Naval Research Laboratory
Authors: J.N. Russell, Jr., Naval Research Laboratory
C.S. Kim, Naval Research Laboratory
Correspondent: Click to Email
High quality AlN films, for optoelectronic devices, high power electronics and sensors, are generally produced via MOCVD of NR@sub 3@ and R@sub 3@Al (R = H, CH@sub 3@, or C@sub 2@H@sub 5@). We explored the chemical interaction of ammonia, methylamine, and ethylamine with clean and hydrogenated Al(111) in an UHV environment using temperature programmed desorption and/or infrared reflection absorption spectroscopy. On clean Al(111), the compounds adsorb molecularly and desorb by 200 K. In contrast, on the H-covered surface, a new desorption state (ß) is seen at about 250 K for each reactant. The ß-state coverage of each compound tracks that of H. Infrared spectroscopy shows that NH@sub 3@ preferentially adsorbs via a Lewis acid-base interaction at monohydride sites with the Al-N bond inclined away from the surface normal. While NH@sub 3@ does not dissociate nor exchange H atoms with the H-precovered surface, the alkylamines dissociate. New HD desorption features, at 240 and 270 K, are observed for perdeutero-alkylamines on H/Al(111). In addition, hydrocarbon desorption is observed at about 600 K for the alkylamines when coadsorbed with hydrogen. We discuss the implications of this work on the MOCVD of AlN films.