Generation of Crystal Defects in Ge-on-Insulator (GOI) Layers in Ge-condensation Process

An ultra-thin body (UTB) Ge-on-insulator (GOI) MISFET is one of the promising candidates for the future devices structure. For fabrication of UTB GOI devices, we have fabricated an ultra-thin GOI layer by oxidizing a SiGe layer grown on an SOI layer, which is called the Ge-condensation technique, However, the GOI devices on substrates fabricated by Ge condensation exhibited large off current which might be attributable to the crystal defects in the GOI layers, hence it is very important to reduce these defects. In this article, in order to obtain an insight into reducing defects, we systematically investigated the generation process of crystal defects in the SiGe or Ge layers during the Ge-condensation process