Method for modulating stresses of a contact etch stop layer

• US 20080085607A1
• Filed: 09/19/2006
• Published: 04/10/2008
• Est. Priority Date: 09/19/2006
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Lu, Yung-Cheng, Yu, Chen-Hua, Chang, Hui-Lin, Tsai, Hung Chun, Shen, Ting-Yu
• Granted Patent: US 7,629,273 B2
• Time in Patent Office: Days
• US Class Current: 438/758
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/823807 with a particular manufacturing method of the channel structures, e.g. channel implants, halo or pocket implants, or channel materials
• CPC Class Codes: H01L 29/7843 the means being an applied insulating layer

Abstract

A method for forming a semiconductor structure includes providing a substrate comprising a first device region, forming a metal-oxide-semiconductor (MOS) device in the first device region, forming a stressed layer over the MOS device, and performing a post-treatment to modulate a stress of the stressed layer. The post-treatment is selected from the group consisting essentially of ultra-violet (UV) curing, laser curing, e-Beam curing, and combinations thereof.

Claims

1. A method for forming a semiconductor structure, the method comprising:

providing a substrate;

forming a stressed layer overlying the substrate, the stressed layer having a first-type stress;

forming a patterned masking layer on the stressed layer; and

performing an electromagnetic radiation treatment on the stressed layer, wherein the first-type stress of an unmasked portion of the stressed layer is convert to a second-type stress.

2. The method of claim 1, wherein the electromagnetic radiation is a UV radiation.

3. The method of claim 1, wherein the first-type stress is a tensile stress and the second-type stress is a compressive stress.

4. The method of claim 1, wherein a dielectric constant of the stressed layer is between about 3 and about 7.

5. The method of claim 1, wherein the stressed layer comprises carbon-doped dielectric.

6. A method for forming a semiconductor structure, the method comprising:

providing a substrate comprising a first device region;

forming a first metal-oxide-semiconductor (MOS) device in the first device region;

forming a stressed layer over the first MOS device; and

performing a post-treatment to modulate a stress of the stressed layer, wherein the post-treatment is selected from the group consisting essentially of ultra-violet (UV) curing, laser curing, e-Beam curing and combinations thereof.

7. The method of claim 6, wherein the stress of the stressed layer is modulated from one of compressive type or tensile type to an opposite type.

8. The method of claim 6, wherein the stress of the stressed layer is increased in magnitude after the step of performing the post-treatment.

9. The method of claim 6, wherein the substrate further comprises:

a second device region; and

an additional MOS device having an opposite type from the first MOS device, wherein the stressed layer is over the additional MOS device, and wherein the stressed layer in the second device region is masked by a mask layer during the step of performing the post-treatment.

10. The method of claim 9 further comprising:

masking the first device region; and

performing an additional post-treatment to the stressed layer in the second device region, wherein process conditions for the post-treatment are substantially different from the process conditions of the additional post-treatment.

11. The method of claim 6, wherein the stressed layer comprises a material selected from the group consisting essentially of carbon-doped silicon oxide, carbon-doped silicon nitride, silicon nitride, silicon oxynitride and combinations thereof.

12. The method of claim 6 further comprising implanting the stressed layer before the step of performing the post-treatment to release the stress.

13. A method for forming a semiconductor structure, the method comprising:

providing a substrate having an active region;

forming an MOS device in the active region;

forming a contact etch stop layer overlying the MOS device, wherein the contact etch stop layer comprises a material selected from the group consisting essentially of carbon-doped silicon oxide, carbon-doped silicon nitride, silicon nitride, silicon oxynitride, and combinations thereof; and

performing a UV curing process to the contact etch stop layer.

14. The method of claim 13, wherein a wavelength of the UV curing process is between about 200 nm and about 400 nm.

15. The method of claim 13, wherein the curing process causes a stress in the contact etch stop layer to change in a tensile direction.

16. The method of claim 13, wherein the curing process causes a stress in the contact etch stop layer to change in a compressive direction.

17. A method for forming a semiconductor structure, the method comprising:

providing a substrate having a first active region and a second active region;

forming a first MOS device in the first active region;

forming a second MOS device having an opposite conductivity type than the first MOS device in the second active region;

forming a contact etch stop layer overlying the first and the second MOS devices;

forming a mask layer to mask the first MOS device; and

performing a curing process to modulate a stress of the contact etch stop layer over the second MOS device, wherein, after the curing process, the stress is of an opposite type than before the curing process, and wherein the curing process is selected from the group consisting essentially of ultra-violet (UV) curing, laser curing, e-Beam curing, and combinations thereof.

18. The method of claim 17, wherein the first MOS device is a PMOS device and the second MOS device is an NMOS device.

19. The method of claim 17 further comprising:

removing the mask layer;

forming an additional mask layer to mask the second MOS device; and

performing an additional curing process, wherein process conditions of the curing process and the additional curing process are substantially different.

20. The method of claim 17 further comprising performing an implantation to the contact etch stop layer after the step of forming the mask layer but before the step of performing the curing process.