Patent ID: 7071080
Filing Date: 2006-07-04
Classification: H01L

Abstract:
1. A process for producing a silicon on insulator structure, the structure comprising a silicon substrate having two major, generally parallel surfaces, one of which is the front surface and the other of which is the back surface, a central plane between the front and back surfaces, a surface layer which comprises a first region of the substrate between the front surface and a distance, D 1 , of at least about 10 micrometers as measured from the front surface and toward the central plane, and a bulk layer which comprises a second region of the substrate between the central plane and the first region, a circumferential edge joining the front and back surfaces, a central axis, and a radius extending from the central axis to the circumferential edge, the process comprising: implanting oxygen into the silicon substrate to cause the formation of a dielectric layer which is generally parallel to the front surface of the substrate and is located in a region between the front surface and the central plane; subjecting the silicon substrate to an ideal precipitating heat treatment to cause the formation of a non-uniform distribution of crystal lattice vacancies, with the concentration of vacancies in the bulk layer being greater than the concentration of vacancies in the surface layer; and, depositing an epitaxial layer on the front surface of the silicon substrate.