Preparation and characterization of atomically clean, stoichiometric surfaces of AIN(0001)

Contributors:   W.J. Mecouch, B.P Wagner, Z.J. Reitmeier, R.F. Davis, C. Pandarinath, B.J. Rodriguez, and Robert J. Nemanich

ABSTRACT

In situ exposure of the (0001) surface of AlN thin films to flowing ammonia at 1120 °C and 10−4Torr removes oxygen∕hydroxide and hydrocarbon species below the detectable limits of x-ray photoelectron spectroscopy and decreases the Al∕N ratio from 1.3 to 1.0. The positions of the Al2𝑝 and the N1𝑠 core level peaks acquired from the cleaned surfaces were 75.0±0.1eV and 398.2±0.1eV, respectively, which were similar to the values determined for the as-loaded samples. The cleaning process left unchanged the (1×1) low energy electron diffraction pattern, the step-and-terrace microstructure, and the root mean square roughness values observed for the surfaces of the as-loaded samples; i.e., the surface structure and microstructure were not changed by the high-temperature exposure to ammonia at low pressures. Vacuum annealing under 10−7Torr at 1175 °C for 15 min removed all detectable hydrocarbons; however, it did not remove the oxygen∕hydroxide species.

Publisher: Journal of Vacuum Science and Technology A,   Volume: 23,   Published: 2004-12 ||   PDF (477.49 KB) ||   Read more...