Strain enhancement for FinFETs

Patent metadata

Field	Value
Publication number	US-9419134-B2
Application number	US-201414153632-A
Country	US
Kind code	B2
Filing date	Jan 13, 2014
Priority date	Jan 13, 2014
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

An integrated circuit device includes a substrate having a first portion in a first device region and a second portion in a second device region. A first semiconductor strip is in the first device region. A dielectric liner has an edge contacting a sidewall of the first semiconductor strip, wherein the dielectric liner is configured to apply a compressive stress or a tensile stress to the first semiconductor strip. A Shallow Trench Isolation (STI) region is over the dielectric liner, wherein a sidewall and a bottom surface of the STI region is in contact with a sidewall and a top surface of the dielectric liner.

First claim

What is claimed is:

1. An integrated circuit device comprising:
a semiconductor substrate comprising a first portion in a first device region and a second portion in a second device region;
a first semiconductor strip in the first device region;
a second semiconductor strip in the second device region;
a first dielectric liner comprising an edge contacting a sidewall of the first semiconductor strip, wherein the first dielectric liner is configured to apply a compressive stress or a tensile stress to the first semiconductor strip; and
a first Shallow Trench Isolation (STI) region over the first dielectric liner, wherein a sidewall and a bottom surface of the first STI region is in contact with a sidewall and a top surface of the first dielectric liner, respectively, with the top surface being directly underlying the first STI region, and the first STI region comprises:
a sidewall in contact with a sidewall of the first dielectric liner; and
a bottom surface comprising a first portion and a second portion, wherein the first portion is in contact with a top surface of the first dielectric liner, and a second portion is in contact with a top surface of the semiconductor substrate.

2. The integrated circuit device of claim 1 further comprising:
a second STI region in the second device region, wherein a sidewall of the second STI region is in contact with a sidewall of the second semiconductor strip, and wherein an entirety of the second STI region is formed of a homogeneous dielectric material, and the first STI region and the first dielectric liner are formed of different materials.

3. The integrated circuit device of claim 2 , wherein a bottom surface of the second STI region is in contact with a top surface of the semiconductor substrate.

4. The integrated circuit device of claim 2 further comprising:
a first additional STI region underlying and overlapped by the first dielectric liner, wherein a bottom surface of the first dielectric liner contacts a top surface of the first additional STI region; and
a second additional STI region underlying and overlapped by the second STI region, wherein a bottom surface of the second STI region contacts a top surface of the second additional STI region.

5. The integrated circuit device of claim 1 further comprising:
a second dielectric liner comprising an edge contacting a sidewall of the second semiconductor strip, wherein the first dielectric liner and the second dielectric liner comprise different materials; and
a second STI region over the second dielectric liner, wherein a sidewall and a bottom surface of the second STI region is in contact with a sidewall and a top surface of the second dielectric liner.

6. The integrated circuit device of claim 5 , wherein bottom surfaces of the first dielectric liner and the second dielectric liner are in contact with top surfaces of the semiconductor substrate.

7. The integrated circuit device of claim 5 further comprising a first additional STI region and a second additional STI region underlying and overlapped by the first dielectric liner and the second dielectric liner, respectively, wherein bottom surfaces of the first dielectric liner and the second dielectric liner contact top surfaces of the first additional STI region and the second additional STI region, respectively.

8. The integrated circuit device of claim 1 , wherein the first dielectric liner is configured to apply the compressive stress to the first semiconductor strip, with the compressive stress having a magnitude higher than about 300 Mpa.

9. The integrated circuit device of claim 1 , wherein the first dielectric liner is configured to apply the tensile stress to the first semiconductor strip, with the tensile stress having a magnitude higher than about 300 Mpa.

10. An integrated circuit device comprising:
a substrate comprising a first portion in a first device region and a second portion in a second device region;
a first semiconductor strip in the first device region;
a first dielectric liner comprising an edge contacting a sidewall of the first semiconductor strip, wherein the first dielectric liner is configured to apply a stress to the first semiconductor strip;
a first Shallow Trench Isolation (STI) region over the first dielectric liner, wherein a sidewall and a bottom surface of the first STI region is in contact with a sidewall and a top surface of the first dielectric liner, respectively;
a second semiconductor strip in the second device region; and
a second STI region, wherein the first STI region and the second STI region are formed of a same homogenous material, and the first STI region and the first dielectric liner are formed of different materials, and wherein a sidewall of the second STI region is in contact with a sidewall of the second semiconductor strip.

11. The integrated circuit device of claim 10 further comprising:
a first additional STI region underlying and overlapped by the first dielectric liner, wherein a bottom surface of the first dielectric liner contacts a top surface of the first additional STI region; and
a second additional STI region underlying and overlapped by the second STI region, wherein a bottom of the second STI region is in contact with a top surface of the second additional STI region.

12. The integrated circuit device of claim 10 , wherein the first dielectric liner is configured to apply a compressive stress to the first semiconductor strip, and wherein the first STI region and the second STI region are configured to apply tensile stresses or neutral stresses to the first semiconductor strip and the second semiconductor strip, respectively.

13. The integrated circuit device of claim 10 , wherein the first dielectric liner is configured to apply a tensile stress to the first semiconductor strip, and wherein the first STI region and the second STI region are configured to apply tensile stresses or neutral stresses to the first semiconductor strip and the second semiconductor strip.

14. The integrated circuit device of claim 10 , wherein the first dielectric liner has a Young's modulus higher than about 100 GPa, and wherein the first STI region and the second STI region are configured to apply tensile stresses or compressive stresses to the first semiconductor strip and the second semiconductor strip.

15. An integrated circuit device comprising:
a first semiconductor strip and a second semiconductor strip over a same semiconductor substrate;
a liner oxide comprising a bottom portion and a sidewall portion, wherein the sidewall portion contacts a sidewall of the first semiconductor strip;
a first Shallow Trench Isolation (STI) region overlapping the bottom portion of the liner oxide, with an edge of the first STI region contacting an edge of the sidewall portion of the liner oxide, wherein a top portion of the first semiconductor strip protrudes over the first STI region to form a first fin, and the first STI region and the liner oxide are formed of different materials;
a first gate dielectric having portions on opposite sidewalls of the first fin;
a second STI region having an edge contacting an edge of the sidewall portion of the second semiconductor strip, wherein the second STI region is formed of a homogenous dielectric material, wherein a top portion of the second semiconductor strip protrudes over the second STI region to form a second fin, and wherein no liner oxide contacts the second STI region; and
a second gate dielectric having portions on opposite sidewalls of the second fin.

16. The integrated circuit device of claim 15 , wherein the first gate dielectric

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Lee Tsung-Lin
• Yeh Chih Chieh
• Yuan Feng
• Chiang Hung-Li
• Lai Wei-Jen

Classifications

• H10P14/69433

  the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz · CPC title

• H10P14/69391

  the material containing aluminium, e.g. Al2O3 · CPC title

• H10P14/69215

  the material being a silicon oxide, e.g. SiO2 · CPC title

• H10P14/6538

  by exposure to UV light · CPC title

• H10P14/6529

  by exposure to a gas or vapour · CPC title