Thick contacts for ultra-thin silicon on insulator films

Claim 1

The method of forming a device with silicon channel regions between silicon source regions and silicon drain regions of an epitaxial silicon film on insulator substrate comprising the steps of: a) forming a protective layer over the silicon film; b) forming a mask layer over the protective layer; c) removing regions of the mask layer to form openings overlying the channel regions; d) thinning the silicon regions underlying the openings leaving the source and drain regions on either side the same thickness as the original silicon film.

Claim 2

The method of forming a device with silicon channel regions between silicon source regions and silicon drain regions of an epitaxial silicon film on insulator substrate comprising the steps of: a) forming a protective layer over the silicon film; b) forming a mask layer over the protective layer; c) removing regions of the mask layer to form openings overlying the channel regions; d) thinning the silicon regions underlying the openings leaving the source and drain regions on either side the same thickness as the original silicon film.

Claim 5

The method of clam 1 wherein the silicon regions are thinned by implantation of oxygen ions in the silicon underlying the openings.

Claim 6

The method of clam 1 wherein the silicon regions are thinned by implantation of oxygen ions in the silicon underlying the openings.

Claim 9

A method for forming a transistor in an epitaxial silicon layer on insulator on silicon substrate comprising the steps of: a) forming a etch stop layer on said silicon layer; b) forming a mask layer on said etch stop layer; c) removing portions of said mask layer to form openings in locations where transistor channel regions are to be formed in said silicon; d) oxidizing said silicon underlying said openings to thin said silicon in said channel regions; e) forming a gate dielectric layer over the silicon layer; f) forming a gate electrode over the channel regions; g) doping the silicon in regions on either side of the gate electrodes to form respective source and drain regions; h) forming metal contacts on the source and drain regions.

Claim 10

A method for forming a transistor in an epitaxial silicon layer on insulator on silicon substrate comprising the steps of: a) forming a etch stop layer on said silicon layer; b) forming a mask layer on said etch stop layer; c) removing portions of said mask layer to form openings in locations where transistor channel regions are to be formed in said silicon; d) oxidizing said silicon underlying said openings to thin said silicon in said channel regions; e) forming a gate dielectric layer over the silicon layer; f) forming a gate electrode over the channel regions; g) doping the silicon in regions on either side of the gate electrodes to form respective source and drain regions; h) forming metal contacts on the source and drain regions.

Claim 11

The method of forming a device with silicon channel regions disposed between laterally adjacent silicon source regions and silicon drain regions of an epitaxial silicon film on insulator substrate comprising the steps of: a) forming a protective layer over the silicon film; b) forming a mask layer over the protective layer; c) removing regions of the mask layer to form openings where the channel regions are to be located; d) thinning the silicon regions underlying the openings leaving thick regions on either side of thin regions where the source and drain regions are to be located; e) removing the mask layer and protective layer and doping the thick regions with a first type conductivity donor and the thin regions between with a second type conductivity donor of opposite conductivity to the first; f) forming an insulator over the thin and thick regions; g) forming a gate electrode over the insulator opposite the thin region; h) forming openings in said insulator to said thick regions; and i) forming contacts in said openings.

Claim 12

The method of forming a device with silicon channel regions disposed between laterally adjacent silicon source regions and silicon drain regions of an epitaxial silicon film on insulator substrate comprising the steps of: a) forming a protective layer over the silicon film; b) forming a mask layer over the protective layer; c) removing regions of the mask layer to form openings where the channel regions are to be located; d) thinning the silicon regions underlying the openings leaving thick regions on either side of thin regions where the source and drain regions are to be located; e) removing the mask layer and protective layer and doping the thick regions with a first type conductivity donor and the thin regions between with a second type conductivity donor of opposite conductivity to the first; f) forming an insulator over the thin and thick regions; g) forming a gate electrode over the insulator opposite the thin region; h) forming openings in said insulator to said thick regions; and i) forming contacts in said openings.