Trench isolation of a CMOS structure

Claim 2

An isolation structure comprising: a substrate having a first active region, a second active region, and a trench region having trench walls provided between the first active region and the second active region, the first active region having a top corner provided where an upper surface and the trench wall of the trench region adjacent to the first active region meet; a refill material provided within the trench region and extending to cover a portion of the top corner; a gate dielectric layer provided on the upper surface of the first active region; and a gate conductor layer provided on an upper surface of the gate dielectric layer, wherein the gate conductor layer is separated from the top corner by the refill material.

Claim 3

The structure of claim 1, wherein the refill material covers the top corner.

Claim 4

The structure of claim 1, wherein the gate conductor layer is a polysilicon gate layer.

Claim 5

The structure of claim 1, wherein the top corner is a rounded corner.

Claim 6

The structure of claim 1, wherein the substrate is a silicon-on-insulator substrate.

Claim 7

The structure of claim 1, wherein the substrate is a silicon bulk substrate.

Claim 8

The structure of claim 1, wherein the trench region is about 0.5 micrometers or less in depth.

Claim 9

The structure of claim 1, wherein the refill material is deposited anisotropically.

Claim 10

The structure of claim 1, wherein the refill material is an oxide.

Claim 11

The structure of claim 1, wherein the refill material is a dielectric material.

Claim 12

The structure of claim 1, wherein the refill material is an intrinsic semiconductor.

Claim 13

The structure of claim 1, wherein the trench region is a shallow trench isolation region.

Claim 14

The structure of claim 1, wherein a field-effect transistor is provided in the first active region.

Claim 15

The structure of claim 1, wherein the trench region walls are substantially vertical.

Claim 16

The structure of claim 1, wherein the trench region walls are angled from vertical.

Claim 17

The structure of claim 1, wherein the gate dielectric is a gate oxide.

Claim 18

An isolation structure comprising: a substrate having a first active region, a second active region, and a trench region having trench walls provided between the first active region and the second active region, the first active region having a first top corner provided where an upper surface and the trench wall of the trench region adjacent to the first active region meet, the second active region having a second top corner provided where an upper surface and the trench wall of the trench region adjacent to the second active region meet; a refill material provided within the trench region and extending to cover a portion of the first top corner and the second top corner; a first gate dielectric layer provided on the upper surface of the first active region; a second gate dielectric layer provided on the upper surface of the second active region; a first gate conductor layer provided on an upper surface of the first gate dielectric layer, wherein the first gate conductor layer is separated from the first top corner by the refill material; and a second gate conductor layer provided on an upper surface of the second gate dielectric layer, wherein the second gate conductor is separated from the second top corner by the refill material.

Claim 19

An isolation structure comprising: a substrate having a first active region, a second active region, and a trench region having trench walls provided between the first active region and the second active region, the first active region having a first top corner provided where an upper surface and the trench wall of the trench region adjacent to the first active region meet, the second active region having a second top corner provided where an upper surface and the trench wall of the trench region adjacent to the second active region meet; a refill material provided within the trench region and extending to cover a portion of the first top corner and the second top corner; a first gate dielectric layer provided on the upper surface of the first active region; a second gate dielectric layer provided on the upper surface of the second active region; a first gate conductor layer provided on an upper surface of the first gate dielectric layer, wherein the first gate conductor layer is separated from the first top corner by the refill material; and a second gate conductor layer provided on an upper surface of the second gate dielectric layer, wherein the second gate conductor is separated from the second top corner by the refill material.

Claim 20

The structure of claim 17, wherein the refill material covers the first top corner and the second top corner.

Claim 21

The structure of claim 17, wherein the first gate conductor layer and the second gate conductor layer are a polysilicon gate layer, the first polysilicon layer serves as the gate for a first metal-oxide field-effect transistor, and the second polysilicon layer serves as the gate for a second metal-oxide field-effect transistor.

Claim 22

The structure of claim 17, wherein the refill material is an oxide.

Claim 23

The structure of claim 17, wherein the refill material is a dielectric material.

Claim 24

The structure of claim 17, wherein the refill material is an intrinsic semiconductor.

Claim 25

The structure of claim 17, wherein the first gate dielectric layer and the second gate dielectric layer are oxide layers.