Photomask

• US 8,512,917 B2
• Filed: 04/26/2011
• Issued: 08/20/2013
• Est. Priority Date: 04/28/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Shishido, Hideaki, Yakubo, Yuto, Oishi, Hirotada
• Primary Examiner(s): ROSASCO, STEPHEN D
• Application Number:
  US13/093,974
• Publication Number:
  US 20110269060A1
• Time in Patent Office: 847 Days
• Field of Search: 430/5, 430/30, 716 50- 56
• US Class Current: 430/5
• CPC Class Codes: G03F 1/36 Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes

Abstract

A photomask is provided, with which the roundness of a corner portion of a resist mask can be reduced in a photolithography step. Further, a method for manufacturing a semiconductor device with less variation is provided. A photomask includes an auxiliary pattern at a corner portion of a light-blocking portion, and (k+1) sides (k is a natural number of 3 or more) form k obtuse angles in the auxiliary pattern. Alternatively, a photomask includes an auxiliary pattern at a corner portion of a light-blocking portion, and the auxiliary pattern includes a zigzag curve.

Claims

1. A photomask comprising:

a light-blocking portion; and

an auxiliary pattern provided at a corner portion of the light-blocking portion,

wherein (k+1) sides (k is a natural number of 3 or more) form k obtuse angles in the auxiliary pattern.

2. The photomask according to claim 1,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 0°

and less than 180° and

the auxiliary pattern has a light-blocking property.

3. The photomask according to claim 1,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 180°

and less than 360° and

the auxiliary pattern has a light-transmitting property.

4. A photomask comprising:

a light-blocking portion; and

an auxiliary pattern provided at a corner portion of the light-blocking portion,

wherein the auxiliary pattern comprises a zigzag curve.

5. The photomask according to claim 4,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 0°

and less than 180° and

the auxiliary pattern has a light-blocking property.

6. The photomask according to claim 4,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 180°

and less than 360° and

the auxiliary pattern has a light-transmitting property.

7. A photomask comprising:

a light-blocking portion; and

an auxiliary pattern provided at a corner portion of the light-blocking portion,

wherein x curves (x is a natural number of 2 or more) each comprising 2l sides (l is a natural number of 2 or more) alternately forming l corners each having a first angle (greater than 0° and

less than 180°

) and (l−

1) corners each having a second angle (greater than 180° and

less than 360°

) are connected to each other in the auxiliary pattern.

8. The photomask according to claim 7, wherein the first angle and the second angle add up to 360°

.

9. The photomask according to claim 7, wherein the first angle is 90°

and the second angle is 270°

.

10. The photomask according to claim 7,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 0°

and less than 180° and

the auxiliary pattern has a light-blocking property.

11. The photomask according to claim 7,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 180°

and less than 360° and

the auxiliary pattern has a light-transmitting property.

12. A photomask comprising:

a light-blocking portion; and

an auxiliary pattern provided at a corner portion of the light-blocking portion,

wherein y first curves (y is a natural number of 2 or more) each comprising 2m sides (m is a natural number of 2 or more) alternately forming m corners each having a first angle (greater than 0° and

less than 180°

) and (m−

1) corners each having a second angle (greater than 180° and

less than 360°

) and z second curves (z is a natural number of 1 or more) each comprising 2n sides (n is a natural number of 1 or more) alternately forming n corners each having a third angle (greater than 180° and

less than 360°

) and (n−

1) corners each having a fourth angle (greater than 0° and

less than 180°

) are connected to each other in the auxiliary pattern, and

wherein each of the second curves is connected between more than one of the first curves.

13. The photomask according to claim 12, wherein the first angle and the second angle add up to 360°

.

14. The photomask according to claim 12, wherein the first angle is 90°

and the second angle is 270°

.

15. The photomask according to claim 12, wherein the third angle and the fourth angle add up to 360°

.

16. The photomask according to claim 12, wherein the third angle is 270°

and the fourth angle is 90°

.

17. The photomask according to claim 12,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 0°

and less than 180° and

the auxiliary pattern has a light-blocking property.

18. The photomask according to claim 12,

wherein an internal angle of a corner portion formed by extended lines of sides of the light-blocking portion is greater than 180°

and less than 360° and

the auxiliary pattern has a light-transmitting property.