METHOD TO INTEGRATE MICRO ELECTRO MECHANICAL SYSTEM AND CMOS IMAGE SENSOR

• US 20100144156A1
• Filed: 12/09/2008
• Published: 06/10/2010
• Est. Priority Date: 12/09/2008
• Status: Abandoned Application

• Current Assignee: United Microelectronics Corporation
• Original Assignee: United Microelectronics Corporation
• Inventors: Shih, Hui-Shen
• Application Number:
  US12/331,422
• Publication Number:
  US 20100144156A1
• Time in Patent Office: Days
• US Class Current: 438/704
• CPC Class Codes: B81C 1/00246 Monolithic integration, i.e. micromechanical structure and electronic processing unit are integrated on the same substrate
• 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 to integrate a micro electro mechanical system and a CMOS image sensor is disclosed. First a substrate is provided. The substrate includes a micro electro mechanical system (MEMS) region and a CMOS image sensor (CIS) region. The micro electro mechanical system region includes a micro electro mechanical system component and the CMOS image sensor region includes a CMOS image sensor element. Second, an etching procedure is performed on the substrate to form a micro electro mechanical system trench and a CMOS image sensor trench. The etching procedure includes at least a dry etching and at least a wet etching.

Claims

1. A method to integrate a micro electro mechanical system and an image sensor, comprising:

providing a substrate comprising a micro electro mechanical system (MEMS) region and an image sensor region, said micro electro mechanical system region comprising a micro electro mechanical system component and said image sensor region comprising an image sensor element; and

performing an etching procedure on said substrate to form a micro electro mechanical system trench in said micro electro mechanical system region and an image sensor trench in said image sensor region, said etching procedure comprising carrying out at least a dry etching and at least a wet etching.

2. The method to integrate a micro electro mechanical system and an image sensor of claim 1, wherein said substrate comprises a protective structure surrounding said micro electro mechanical system region.

3. The method to integrate a micro electro mechanical system and an image sensor of claim 1, further comprising:

forming a micro electro mechanical system in said micro electro mechanical system region and an image sensor in said image sensor region.

4. The method to integrate a micro electro mechanical system and an image sensor of claim 1, wherein said micro electro mechanical system component comprises a diaphragm.

5. The method to integrate a micro electro mechanical system and an image sensor of claim 1, wherein said micro electro mechanical system component comprises a motion sensor.

6. The method to integrate a micro electro mechanical system and an image sensor of claim 1, wherein said image sensor comprises a CMOS Image Sensor (CIS).

7. The method to integrate a micro electro mechanical system and an image sensor of claim 1, wherein said dry etching is first carried out in said etching procedure.

8. The method to integrate a micro electro mechanical system and an image sensor of claim 7, wherein said dry etching exposes said micro electro mechanical system component in said micro electro mechanical system region.

9. The method to integrate a micro electro mechanical system and an image sensor of claim 1, wherein a fluoride is used as an etchant in said wet etching.

10. The method to integrate a micro electro mechanical system and an image sensor of claim 9, wherein said etchant is a liquid fluoride.

11. The method to integrate a micro electro mechanical system and an image sensor of claim 9, wherein said etchant is a gaseous fluoride.

12. The method to integrate a micro electro mechanical system and an image sensor of claim 1, wherein said dry etching step is carried out to construct 80%-90% of a total depth.

13. The method to integrate a micro electro mechanical system and an image sensor of claim 12, wherein said wet etching step proceeds to finish the remaining depth 20%-10%.