Using scanning probe microscopy, we have examined the surfaces produced by etching several different vicinal Si(111) samples in NH4F aqueous solution. In agreement with others, we found that deoxygenation of the etchant generally reduces the number of triangular etch pits. We also found that for maximum uniformity and minimum roughness, a certain minimum miscut angle is required. This angle is related to the maximum clear terrace width, which in turn is related to the relative etching rate of the step-edge sites and the terrace sites.
Citation: Applied Physics Letters
Issue: No. 18
Pub Type: Journals
atom-based dimensional metrology, atomically flat and ordered silicon, hydrogen terminated surfaces, metrology, silicon surfaces