Patent ID: 7084050

Claim:
A method of producing a substantially relaxed, high-quality SiGe-on-insulator substrate material comprising the steps of: subjecting a Si-containing substrate to a base oxygen ion implant step to form a damaged region that has an oxygen ion concentration that is sufficient to act as a diffusion barrier to Ge; subjecting the Si-containing substrate having said damaged region to a second oxygen implant step to form an amorphous region that is shallower than the damaged region, said amorphous region having a surface layer of the Si-containing substrate thereon; forming a Ge-containing layer atop the surface layer of the Si-containing substrate, said Ge-containing layer having a thickness from about 50 to about 500 nm and a Ge content from about 5 to about 40 atomic %; heating the substrate to form a substantially relaxed SiGe layer atop said diffusion barrier layer, said heating comprises: (i) first ramping up the substrate in an oxygen-containing gas to a first temperature that is sufficient to initiate formation of a buried oxide region in said substrate, while substantially avoiding slip generation; (ii) first soaking at the first temperature to form a continuous buried oxide in said substrate; (iii) second ramping up in an oxygen-containing gas from the first temperature to a second temperature that is sufficient to increase the thickness of the buried oxide in said substrate; (iv) second soaking in an oxygen-containing gas at said second temperature to increase and control the thermal oxide thickness and to provide a sharpened interface between the relaxed SiGe layer and the buried oxide; (v) ramping down from the second temperature to a third temperature that is less than or equal to the melting point of a final desired Ge concentration, while allowing Ge diffusion for concentration homogenization; and (vi) oxidizing at said third temperature to provide the relaxed SiGe layer having said final Ge content and a thickness that is sufficient to minimize stacking faults.