MEMS package structure

• US 9,000,544 B2
• Filed: 08/01/2014
• Issued: 04/07/2015
• Est. Priority Date: 08/11/2009
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: PixArt Imaging Incorporated
• Inventors: Hsu, Hsin-Hui, Lee, Sheng-Ta, Wang, Chuan-Wei
• Primary Examiner(s): FOURSON III, GEORGE R
• Application Number:
  US14/449,583
• Publication Number:
  US 20140339655A1
• Time in Patent Office: 249 Days
• Field of Search: 438/51, 438/52, 438/53, 438/124, 257/415, 257/704
• US Class Current: 257/415
• CPC Class Codes: B81B 2201/0264 Pressure sensors
• CPC Class Codes: B81B 7/0006 Interconnects
• CPC Class Codes: B81B 7/0058 for protecting against damages due to external chemical or mechanical influences, e.g. shocks or vibrations
• 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: B81C 1/00293 maintaining a controlled atmosphere with processes not provided for in B81C1/00285
• CPC Class Codes: B81C 2203/0136 Growing or depositing of a covering layer
• CPC Class Codes: B81C 2203/0145 Hermetically sealing an opening in the lid
• CPC Class Codes: B81C 2203/0714 Forming the micromechanical structure with a CMOS process
• CPC Class Codes: B81C 2203/0735 Post-CMOS, i.e. forming the micromechanical structure after the CMOS circuit

Abstract

A MEMS package structure, including a substrate, an interconnecting structure, an upper metallic layer, a deposition element and a packaging element is provided. The interconnecting structure is disposed on the substrate. The MEMS structure is disposed on the substrate and within a first cavity. The upper metallic layer is disposed above the MEMS structure and the interconnecting structure, so as to form a second cavity located between the upper metallic layer and the interconnecting structure and communicates with the first cavity. The upper metallic layer has at least a first opening located above the interconnecting structure and at least a second opening located above the MEMS structure. Area of the first opening is greater than that of the second opening. The deposition element is disposed above the upper metallic layer to seal the second opening. The packaging element is disposed above the upper metallic layer to seal the first opening.

Claims

1. A MEMS package structure, comprising:

a substrate;

an interconnecting structure disposed on the substrate and having a third cavity;

a buffering element partially disposed within the third cavity;

a supporting layer partially suspended above the third cavity, the supporting layer having a fifth opening defined above the third cavity and exposing a portion of the buffering element; and

a packaging layer disposed on the supporting layer and filling into the fifth opening to connect with the buffering element.

2. The MEMS package structure as claimed in claim 1, wherein material of the packaging layer comprises metal.

3. The MEMS package structure as claimed in claim 1, wherein material of the packaging layer comprises aluminum.

4. The MEMS package structure as claimed in claim 1, further comprising an insulating structure disposed on the substrate and surrounding the third cavity.

5. The MEMS package structure as claimed in claim 4, further comprising a non-doped polysilicon layer disposed between the insulating structure and the substrate.

6. The MEMS package structure as claimed in claim 1, wherein a portion of the buffering element in the third cavity is connected with the substrate.

7. The MEMS package structure as claimed in claim 1, wherein a portion of the buffering element in the third cavity is suspended above the substrate.

8. The MEMS package structure as claimed in claim 7, further comprising a stopping element disposed between the substrate and the buffering element, the buffering element and the stopping element defining a first interval therebetween.

9. The MEMS package structure as claimed in claim 8, further comprising a movable element partially disposed in the third cavity and suspended above the substrate.

10. The MEMS package structure as claimed in claim 9, wherein the movable element and the supporting layer define a second interval therebetween, and the second interval is greater than the first interval.