The preparation of {00•1} surfaces of hexagonal 4H- and 6H-type material, by H plasma or etching in a H flux, produced highly ordered monolayers of SiO2. Their structure, and epitaxial relationship with respect to the SiC substrate, were analyzed by means of quantitative low-energy electron diffraction and Auger electron spectroscopy. The resultant bond-angles and distances agreed with those of the bulk oxide. Due to the saturation of all of the dangling bonds, the semiconductor surface was passivated and preserved its perfect order in air. The essentially ideal oxide monolayers could thus serve as seeds for the growth of epitaxial oxides with a low defect density and with only a few structural distortions at the interface with the SiC substrate.

Epitaxially Ideal Oxide Semiconductor Interfaces: Silicate Adlayers on Hexagonal (0001) and (000¯1) SiC Surfaces. J.Bernhardt, J.Schardt, U.Starke, K.Heinz: Applied Physics Letters, 1999, 74[8], 1084-6