ANTI-REFLECTION COATING LAYER AND DESIGN METHOD THEREOF

• US 20060268415A1
• Filed: 05/26/2005
• Published: 11/30/2006
• Est. Priority Date: 05/26/2005
• Status: Active Grant

• Current Assignee: Macronix International Co., Ltd.
• Original Assignee: Macronix International Co., Ltd.
• Inventors: Huang, Chun-Chung
• Granted Patent: US 7,321,467 B2
• Time in Patent Office: Days
• US Class Current: 359/582
• CPC Class Codes: G02B 1/11 Anti-reflection coatings
• CPC Class Codes: G02B 1/113 using inorganic layer materials only

Abstract

An anti-reflection coating layer is formed between an under layer and a photoresist layer. The anti-reflection coating is characterized in a refraction value (n) of the anti-reflection coating layer, wherein n is a constant, and an extinction coefficient (k) of the anti-reflection coating layer, increasing in gradient toward the under layer. Thus, the substrate reflectivity with respect to different under layers can be substantially equal to 0 by controlling the k of the anti-reflection coating layer.

Claims

1. An anti-reflection coating layer suitable to be formed between an under layer and a photoresist layer, the anti-reflection coating layer characterized in:

a refraction (n) of the anti-reflection coating layer, wherein n is a constant; and

an extinction coefficient (k) of the anti-reflection coating layer, wherein k is increased in gradient toward the under layer.

2. The anti-reflection coating layer of claim 1, wherein an increment of the value k of the anti-reflection coating layer is larger than 0 and smaller than 2.

3. The anti-reflection coating layer of claim 1, wherein the k of the anti-reflection coating layer is increased in gradient from a top set as 0 to the under layer.

4. The anti-reflection coating layer of claim 1, wherein a number of times the k of the anti-reflection coating layer is increased in gradient toward the under layer is at least 2.

5. The anti-reflection coating layer of claim 1, wherein each anti-reflection coating layer with different k has a different thickness.

6. The anti-reflection coating layer of claim 5, wherein a thickness of each anti-reflection coating layer with a different k is gradually increased toward the under layer.

7. The anti-reflection coating layer of claim 1, wherein a thickness of the anti-reflection coating layer is a constant.

8. The anti-reflection coating layer of claim 1, wherein the n of the anti-reflection coating layer is larger than an n of the photoresist layer.

9. The anti-reflection coating layer of claim 1, wherein the n of the anti-reflection coating layer is larger than 1.8.

10. A method of designing an anti-reflection coating layer, for substantially reducing a substrate reflectivity of the anti-reflection coating layer to zero, the method comprising:

providing an anti-reflection coating layer formed between an under layer and a photoresist layer;

making a refraction (n) of the anti-reflection layer a constant; and

increasing an extinction coefficient (k) of the anti-reflection layer in gradient toward the under layer.

11. The method of designing an anti-reflection coating layer of claim 10, wherein an increment of the value k of the anti-reflection coating layer is larger than 0 and smaller than 2.

12. The anti-reflection coating layer of claim 10, wherein the k of the anti-reflection coating layer is increased in gradient from a top set as 0 to the under layer.

13. The anti-reflection coating layer of claim 10, wherein a number of times the k of the anti-reflection coating layer is increased in gradient toward the under layer is at least 2.

14. The anti-reflection coating layer of claim 10, wherein each anti-reflection coating layer with a different k has a different thickness.

15. The anti-reflection coating layer of claim 14, wherein the thickness of each anti-reflection coating layer with a different k is gradually increased toward the under layer.

16. The anti-reflection coating layer of claim 10, wherein the thickness of the anti-reflection coating layer is a constant.

17. The anti-reflection coating layer of claim 10, wherein the n of the anti-reflection coating layer is larger than an n of the photoresist layer.

18. The anti-reflection coating layer of claim 10, wherein the n of the anti-reflection coating layer is larger than 1.8.

19. The anti-reflection coating layer of claim 10, wherein the under layer comprises a silicon oxide layer, a silicon nitride layer, a polysilicon layer, a metal layer or a silicon substrate.