Photomask, method for producing the same, and method for forming pattern using the photomask

• US 7,282,309 B2
• Filed: 11/13/2006
• Issued: 10/16/2007
• Est. Priority Date: 04/30/2002
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Misaka, Akio
• Primary Examiner(s): Young; Christopher G.
• Application Number:
  US11/598,003
• Publication Number:
  US 20070054204A1
• Time in Patent Office: 337 Days
• Field of Search: 430/5, 430/311, 430/322, 430/323, 430/324, 430/396
• US Class Current: 430/5
• CPC Class Codes: G03F 1/29 Rim PSM or outrigger PSM; Preparation thereof
• CPC Class Codes: G03F 1/32 Attenuating PSM [att-PSM], e.g. halftone PSM or PSM having semi-transparent phase shift portion,; Preparation thereof

Abstract

A photomask includes a semi-light-shielding portion having a light-shielding property, a light-transmitting portion surrounded by the semi-light-shielding portion and a peripheral portion positioned in a periphery of the light-transmitting portion on a transparent substrate. The semi-light-shielding portion and the light-transmitting portion transmit the exposure light in the same phase each other, whereas the peripheral portion transmits the exposure light in a phase opposite to that of the light-transmitting portion. A phase shift film that transmits the exposure light in a phase opposite to that of the peripheral portion is formed on the transparent substrate-in the semi-light-shielding portion formation region.

Claims

1. A photomask on a transparent substrate comprising:

a first phase shifter having a semi-light-shielding property with respect to exposure light;

a second phase shifter surrounded by the first phase shifter and having a light-transmitting property with respect to exposure light; and

an opening surrounded by the first phase shifter and positioned in a periphery of the second phase shifter,

wherein the first phase shifter and the second phase shifter transmit the exposure light in a same phase, and

the opening transmits the exposure light in a phase opposite to that of the first phase shifter and the second phase shifter.

2. The photomask according to claim 1,

wherein a first phase shift film is formed on the transparent substrate, as the first phase shifter.

3. The photomask according to claim 1,

wherein a substrate-dug portion is formed by digging the transparent substrate, as the second phase shifter.

4. The photomask according to claim 1,

wherein a second phase shift film is formed on the transparent substrate, as the second phase shifter.

5. The photomask according to claim 1,

wherein in the opening, the first phase shifter and the second phase shifter are not formed.

6. The photomask according to claim 1,

wherein a transmittance with respect to the exposure light of the first phase shifter is 6% or more and 15% or less.

7. The photomask according to claim 1,

wherein a transmittance with respect to the exposure light of the second phase shifter is 60% or more.

8. The photomask according to claim 1,

wherein a first phase shift film is formed on the transparent substrate, as the first phase shifter, and

a substrate-dug portion is formed by digging the transparent substrate, as the second phase shifter.

9. The photomask according to claim 1,

wherein a transmittance with respect to the exposure light of the first phase shifter is lower than a transmittance with respect to the exposure light of the second phase shifter.

10. The photomask according to claim 1,

wherein a transmittance with respect to the exposure light of the first phase shifter is 6% or more and 15% or less, and

a transmittance with respect to the exposure light of the second phase shifter is 60% or more.

11. The photomask according to claim 1,

wherein the second phase shifter has a square shape or rectangular shape, and

the opening comprises a ring-shaped region in contact with the peripheral portion of the second phase shifter.

12. The photomask according to claim 1,

wherein the second phase shifter has a square shape or rectangular shape, and

the opening comprises a plurality of rectangular regions each of which is in contact with each side of the second phase shifter.

13. The photomask according to claim 1,

wherein the second phase shifter has a square shape or rectangular shape,

the opening comprises a ring-shaped region, and

a part of the first phase shifter having a ring shape is present between the opening and the second phase shifter.

14. The photomask according to claim 1,

wherein the second phase shifter has a square shape or rectangular shape,

the opening comprises a plurality of rectangular regions each facing with a side of the second phase shifter, and

a part of the first phase shifter having a ring shape is present between the opening and the second phase shifter.

15. The photomask according to claim 1,

wherein the exposure light transmitted through the first phase shifter and the exposure light transmitted through the opening have a phase difference of (150+360×

n) degrees or more and (210+360×

n) degrees or less (where n=an integer), and

the exposure light transmitted through the second phase shifter and the exposure light transmitted through the opening have a phase difference of (150+360×

n) degrees or more and (210+360×

n) degrees or less (where n=an integer).

16. The photomask according to claim 8,

wherein the first phase shift film is a metal-containing oxide film.

17. The photomask according to claim 8,

wherein the first phase shift film includes a transmittance adjusting film having a transmittance lower than that of the transparent substrate with respect to the exposure light and a phase adjusting film that is formed on the transmittance adjusting film, and transmits the exposure light in a phase opposite to that of the opening.

18. The photomask according to claim 17,

wherein the opening is disposed in a position apart from the second phase shifter by a predetermined distance, and

only the transmittance adjusting film of the first phase shift film is formed between the opening and the second phase shifter.

19. The photomask according to claim 1,

wherein the opening is disposed so as to be in contact with the second phase shifter.

20. The photomask according to claim 1,

wherein the opening is disposed apart from the second phase shifter by a predetermined distance.