Patent ID: 7566482
Filing Date: 2009-07-28
Classification: C25F,H01L

Abstract:
1. A method of fabricating a silicon-on-insulator substrate comprising: a first ion implanting step to implant p-type or n-type dopants into a Si-containing substrate to a depth ranging from 250 nm to 1500 nm from a top surface of the Si-containing substrate; a second ion implanting step following the first ion implanting step to implant at least one ion selected from the group consisting of Si, Ge, Ne, Bi, Sn and Xe, wherein the at least one ion may be implanted to below, above or within the depth at which the p-type or n-type dopants are present in the Si-containing substrate; annealing the n-type or p-type dopants following the second ion implanting step to provide an activated n-type or p-type dopant region in the Si-containing substrate; performing an electrolytic anodization process comprising immersing the Si-containing substrate into an HF-containing solution and applying a current density ranging from 0.05 milliAmps/cm thermal oxidizing at a temperature ranging from 650° C. to 1350° C. to convert at least a portion of the porous Si region into a buried oxide region, wherein a portion of the Si-containing substrate overlying the buried oxide region and a remaining portion of the porous Si region coalesces to provide a Si-containing overlayer.