MOSFETs with Channels on Nothing and Methods for Forming the Same
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsGeorgios Vellianitis, Mark Van Dal, Blandine Duriez
Life of this patent
Estimating the term…
Abstract
A device includes a semiconductor substrate, and a channel region of a transistor over the semiconductor substrate. The channel region includes a semiconductor material. An air gap is disposed under and aligned to the channel region, with a bottom surface of the channel region exposed to the air gap. Insulation regions are disposed on opposite sides of the air gap, wherein a bottom surface of the channel region is higher than top surfaces of the insulation regions. A gate dielectric of the transistor is disposed on a top surface and sidewalls of the channel region. A gate electrode of the transistor is over the gate dielectric.
Claims21
A device comprising:
- a semiconductor substrate;
- a channel region of a transistor over the semiconductor substrate, wherein the channel region comprises a semiconductor material;
- an air gap under and aligned to the channel region, with a bottom surface of the channel region exposed to the air gap;
- insulation regions on opposite sides of the air gap, wherein a bottom surface of the channel region is higher than top surfaces of the insulation regions;
- a gate dielectric of the transistor on a top surface and sidewalls of the channel region;
- and
- a gate electrode of the transistor over the gate dielectric.
A device comprising:
- a semiconductor substrate;
- insulation regions at a top portion of semiconductor substrate, wherein the insulation regions comprise two sidewalls facing each other, and wherein the opposite sidewalls are spaced apart from each other by a space;
- a channel region comprising a semiconductor material over the semiconductor substrate and aligned to the space;
- an air gap underlying and aligned to the channel region, wherein the air gap comprises first edges substantially aligned to respective ones of the two sidewalls of the insulation regions;
- a gate dielectric on a top surface and sidewalls of the channel region;
- and
- a gate electrode over the gate dielectric, wherein the channel region, the gate dielectric, and the gate electrode form parts of a transistor.
15-20. (canceled)
A device comprising:
- a semiconductor substrate;
- insulation regions extending into the semiconductor substrate;
- a first and a second epitaxy region spaced apart from each other, wherein the first and the second epitaxy regions extend from a level above top surfaces of the insulation regions into the insulation regions;
- a semiconductor layer above the top surfaces of the insulation regions, wherein opposite ends of the semiconductor layer is supported by the first and the second epitaxy regions, and wherein a center portion of the semiconductor layer is overlying an air gap;
- a gate dielectric of a transistor on a top surface and sidewalls of the center portion of the semiconductor layer;
- and
- a gate electrode of the transistor over the gate dielectric.
Dependencies are inferred from the claim text.