Radiation damage in Si1−x Ge x heteroepitaxial devices

Abstract

Results are presented of an extended study on the induced lattice defects and their effects on the degradation of Sil_xGex devices, subjected to a 20 MeV alpha-ray, 1 MeV electron, 1 MeV fast neutron, and 20 and 86 MeV proton irradiations. The degradation of the electrical device performance increases with increasing fluence, while it decreases with increasing germanium content. In the Sil_xGe x epitaxial layers, electron capture levels associated with an interstitial-substitutional boron complex are induced. The radiation source dependence of performance degradation is attributed to the difference of mass and the probability of nuclear collision for the formation of lattice defects.