Micro-RBS characterisation of the chemical composition and particulate deposition on pulsed laser deposited Si1-xGex thin films

The formation and deposition of particulates by pulsed laser deposition of Si1-xGex semiconductor alloy thin films are discussed. Using Rutherford backscattering spectrometry with micrometer lateral resolution (micro-RBS) the film composition was measured with high accuracy, even in the presence of particulates with a high areal density of 20,000-30,000 particulates per mm2. We show that on impact of a particulate, the part of the thin film which is already deposited probably melts and its Ge content segregates to the surface