Patterned SOI by oxygen implantation and annealing

A method of fabricating a patterned SOI substrate having fine geometries, said method comprising the steps of:

• (a) forming a patterned dielectric mask on a surface of a Si-containing substrate, wherein said patterned dielectric mask includes vertical edges that define boundaries for at least one opening which exposes a portion of said Si-containing substrate;
• (b) implanting oxygen ions through said at least one opening using oxygen implant conditions that minimize erosion of the vertical edges of the patterned dielectric mask and minimize formation of a lateral straggle under the vertical edges of said patterned dielectric mask;
• (c) forming a Si-containing layer on said exposed portion of said Si-containing substrate;
• and
• (d) annealing said Si-containing substrate at a temperature of about 1250° C. or above and in an oxidizing ambient so as to form at least one discrete buried oxide region in said Si-containing substrate.

A method of fabricating a patterned SOI substrate having fine geometries, said method comprising the steps of:

• (a) forming a patterned dielectric mask on a surface of a Si-containing substrate, wherein said patterned dielectric mask includes vertical edges that define boundaries for at least one opening which exposes a portion of said Si-containing substrate;
• (b) implanting oxygen ions through said at least one opening using oxygen implant conditions that minimize erosion of the vertical edges of the patterned dielectric mask and minimize formation of a lateral straggle under the vertical edges of said patterned dielectric mask;
• (c) annealing said Si-containing substrate at a temperature of about 1250° C. or above and in an oxidizing ambient so as to form at least one discrete buried oxide region in said Si-containing substrate;
• and
• (d) removing said patterned dielectric mask and forming a Si-containing layer on said exposed portion of said Si-containing substrate.