Ion beam analysis of porous silicon layers

The composition of porous silicon layers prepared by anodising silicon in H F-methanol medium has been studied using a combination of nuclear resonance reaction analysis (NRRA) and non-Rutherford backscattering spectrometry. T he H-1(N-15, alpha gamma)C-12 resonance reaction has been used for determin ing depth distribution of hydrogen in the films. The distribution of other low Z elements like C, O and Si has been probed and the ratio of their atom ic concentrations determined using C-12(alpha, alpha)C-12 and O-16(alpha, a lpha)O-16 scattering. Anodisation resulted in the formation of Si1CchiHgamm a. layers. The composition and thickness of the layers depend on the condit ions of preparation. (C) 2001 Elsevier Science B.V. All rights reserved.