Depth profiling of hydrogen in crystalline silicon using elastic recoil detection analysis

Abstract

Accurate depth profiling of hydrogen in crystalline silicon (c-Si) from reflection elastic recoil detection analysis (ERDA) can be performed using a method that converts the channel difference between surface and bulk signals directly to depth. The method relies on Rutherford backscattering spectrometry (RBS) to unambiguously determine the depth of a buried marker coincident with a hydrogen distribution in each of several silicon calibration standards. A conversion from ERDA channels to depth is extracted from the relationship between the depth to the marker and the channel difference between surface and bulk hydrogen centroids in forward recoil spectra acquired simultaneously. Applying this conversion to ERDA of hydrogen-implanted c-Si taken under the same conditions as those of the silicon calibration standards results in accurate, quantitative depth profiling. A comparison of techniques shows that this method offers distinct advantages over depth profiling by computer simulation of ERDA spectra.