Method of manufacturing a CMOS image sensor

• US 20040142568A1
• Filed: 12/24/2003
• Published: 07/22/2004
• Est. Priority Date: 12/30/2002
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: DONGBU ELECTRONICS CO., LTD. (DB HiTek Co., Ltd.)
• Inventors: Jung, Meng An
• Granted Patent: US 7,094,519 B2
• Time in Patent Office: Days
• US Class Current: 438/689
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14627 Microlenses
• CPC Class Codes: H01L 27/14685 Process for coatings or optical elements

Abstract

A method of manufacturing a CMOS image sensor. The present invention enables forming micro-lenses having a uniform shape throughout a semiconductor substrate. The method of manufacturing a CMOS image sensor includes: coating a color filter layer and a semiconductor substrate with a first photoresist; selectively exposing the first photoresist to light to define a planarization layer; coating the first photoresist with a second photoresist; selectively exposing the second photoresist to define a plurality of micro-lens bodies; and baking the plurality of micro-lens bodies to form a plurality of micro-lenses.

Claims

1. A method of manufacturing -microlenses in a CMOS image sensor, comprising:

(a) coating a filter layer over a semiconductor substrate with a first photoresist;

(b) selectively exposing the first photoresist to light;

(c) coating the first photoresist with a second photoresist;

(d) selectively exposing the second photoresist to light to define a plurality of micro-lens bodies; and

(e) heating the plurality of micro-lens bodies to form a plurality of micro-lenses.

2. The method according to claim 1, further comprising removing unexposed parts of the second photoresist after selectively exposing the second photoresist.

3. The method according to claim 1, wherein the first photoresist has a thickness of from about 1.3 μ

m to about 3 μ

m.

4. The method according to claim 1, wherein the second photoresist has a thickness of from about 1.1 μ

m to about 1.3 μ

m.

5. The method according to claim 1, wherein the first photoresist comprises a negative-type photoresist.

6. The method according to claim 5, wherein the second photoresist comprises a positive-type photoresist.

7. The method according to claim 2, wherein the second photoresist comprises a positive-type photoresist.

8. The method according to claim 7, wherein the first photoresist comprises a negative-type photoresist.

9. The method according to claim 2, further comprising removing exposed parts of the first photoresist after removing unexposed parts of the second photoresist.

10. The method according to claim 9, wherein the second photoresist comprises a positive-type photoresist.

11. The method according to claim 10, wherein the first photoresist comprises a negative-type photoresist.

12. The method according to claim 1, wherein an amount of energy in the step of selectively exposing the second photoresist is from about 300 mJ to about 500 mJ.

13. The method according to claim 1, further comprising the step of forming a color filter layer on the semiconductor substrate.

14. The method according to claim 1, wherein the filter layer comprises a color filter layer.