Metal-oxide semiconductor transistors
The present disclosure relates to semiconductor structures and, more particularly, to metal-oxide semiconductor transistors and methods of manufacture. The structure includes: a substrate comprising a drift region and a body region; a gate structure between the drift region and the body region; an insulator material over the gate structure, the drift region and the body region; and an air gap within the insulator material and extending into the drift region.
1 . A structure comprising:
a substrate comprising a drift region and a body region;
a gate structure between the drift region and the body region;
an insulator material over the gate structure, the drift region and the body region; and
an air gap within the insulator material and extending into the drift region,
wherein the air gap extends through a dielectric layer partially under a gate electrode of the gate structure.
2 . The structure of claim 1 , wherein the dielectric layer comprises oxide material.
3 . The structure of claim 2 , wherein the drift region comprises an extended drain region and the body region comprises a source region.
4 . The structure of claim 1 , further comprising a field plate extending from the body region, over the gate structure and adjacent to the air gap.
5 . The structure of claim 4 , wherein the field plate extends over the air gap.
6 . The structure of claim 5 , wherein the field plate is provided on an upper metallization layer.
7 . The structure of claim 1 , further comprising a shallow trench isolation structure within the drift region.
8 . The structure of claim 7 , wherein the air gap extends partially into the shallow trench isolation structure.
9 . The structure of claim 8 , further comprising a field plate extending from the body region, over the gate structure and adjacent to the air gap.
10 . The structure of claim 9 , wherein the field plate extends over the air gap.
11 . A structure comprising:
a substrate comprising a drift region and a body region;
a gate structure between the drift region and the body region;
a field plate extending from the body region, over the gate structure and towards the drift region; and
an air gap extending into the body region.
12 . The structure of claim 11 , wherein the drift region comprises an extended drain region and the body region comprises a source region.
13 . The structure of claim 11 , wherein the field plate extends over the air gap.
14 . The structure of claim 11 , wherein the field plate extends adjacent to the air gap.
15 . The structure of claim 11 , wherein the field plate is on an upper metallization layer, with a lower metallization layer coincident with the air gap.
16 . The structure of claim 11 , further comprising a shallow trench isolation structure within the drift region, and the air gap extends partially into the shallow trench isolation structure.
17 . The structure of claim 16 , wherein the field plate extends over the air gap.
18 . A method comprising:
forming a substrate comprising a drift region and a body region;
forming a gate structure between the drift region and the body region; forming an insulator material over the gate structure, the drift region and the body region; and
forming an air gap within the insulator material and extending into the body region, wherein the air gap extends through a dielectric layer partially under a gate electrode of the gate structure.