Alternating phase shift mask

• US 6,977,127 B2
• Filed: 12/16/2002
• Issued: 12/20/2005
• Est. Priority Date: 01/17/2002
• Status: Expired due to Term

• Current Assignee: Winbond Electronics Corporation
• Original Assignee: Winbond Electronics Corporation
• Inventors: Shiah, Chii-Ming, Tung, Yu-Cheng, Liao, Hung-Yueh, Tsai, Kao-Tsai, Wang, Jong-Bor, Hsu, Yi-Yu
• Primary Examiner(s): ROSASCO, STEPHEN D
• Application Number:
  US10/320,243
• Publication Number:
  US 20030134207A1
• Time in Patent Office: 1,100 Days
• Field of Search: 430/5, 430/22, 430/322, 430/394
• US Class Current: 430/5
• CPC Class Codes: G03F 1/30 Alternating PSM, e.g. Levenson-Shibuya PSM; Preparation thereof

Abstract

An alternating phase shift mask. The alternating phase shift mask includes a transparent substrate, a light-shielding layer disposed on the transparent substrate to define a transparent array consisting of a plurality of first phase rows and a plurality of second phase rows alternately interposed between the first phase rows. The alternating phase shift mask further comprises a phase interference enhancement feature disposed a predetermined distance from the outermost row of the transparent array, wherein the phases of the phase interference enhancement feature and the outermost row are reverse.

Claims

1. An alternating phase shift mask, comprising:

a transparent substrate;

a light-shielding layer on the transparent substrate to define a transparent array consisting of a plurality of first phase rows and a plurality of second phase rows alternately interposed between the first phase rows; and

a phase interference enhancement feature disposed a predetermined distance from the outermost row of the transparent array, wherein the phases of the phase interference enhancement feature and the outermost row are reverse.

2. An alternating phase shift mask as claimed in claim 1, wherein the transparent substrate is a quartz substrate.

3. An alternating phase shift mask as claimed in claim 1, wherein the light-shielding layer consists of chromium.

4. An alternating phase shift mask as claimed in claim 1, wherein the polysilicon layer, wherein the phase interference enhancement feature is a transparent stripe.

5. An alternating phase shift mask as claimed in claim 4, wherein the polysilicon layer, wherein the transparent stripe has a width of about 50 nanometers to about 80 nanometers.

6. An alternating phase shift mask as claimed in claim 4, wherein the predetermined distance between the outermost row of the transparent array and the phase interference enhancement feature is between 50 nanometers and 200 nanometers.

7. An alternating phase shift mask as claimed in claim 1, wherein the polysilicon layer, wherein the phase interference enhancement feature comprises a plurality of transparent blocks.

8. An alternating phase shift mask as claimed in claim 1, wherein the first phase is 0 degrees and the second phase is 180 degrees.

9. An alternating phase shift mask as claimed in claim 5, wherein the phase interference enhancement feature has a dimension that cannot transfer to a photoresist layer during photolithography.

10. An alternating phase shift mask, comprising:

a transparent substrate;

a light-shielding layer disposed on the transparent substrate to define a transparent array consisting of a plurality of first phase columns and a plurality of second phase columns alternately interposed between the first phase columns; and

a phase interference enhancement feature disposed a predetermined distance from the outermost column of the transparent array, wherein the phases of the phase interference enhancement feature and the outermost column are reversed.

11. An alternating phase shift mask as claimed in claim 10, wherein the transparent substrate is a quartz substrate.

12. An alternating phase shift mask as claimed in claim 10, wherein the light-shielding layer consists of chromium.

13. An alternating phase shift mask as claimed in claim 10, wherein the polysilicon layer, wherein the phase interference enhancement feature is a transparent stripe.

14. An alternating phase shift mask as claimed in claim 13, wherein the polysilicon layer, wherein the transparent stripe has a width of about 50 nanometers to about 80 nanometers.

15. An alternating phase shift mask as claimed in claim 13, wherein the predetermined distance between the outermost column of the transparent array and the phase interference enhancement feature is between 50 nanometers and 200 nanometers.

16. An alternating phase shift mask as claimed in claim 10, wherein the polysilicon layer, wherein the phase interference enhancement feature comprises a plurality of transparent blocks.

17. An alternating phase shift mask as claimed in claim 10, wherein the first phase is 0 degree and the second phase is 180 degree.

18. An alternating phase shift mask as claimed in claim 14, wherein the phase interference enhancement feature has a dimension that cannot transfer to a photoresist layer during photolithography.