Manufacturing method of MEMS chip

Patent metadata

Field	Value
Publication number	US-10077188-B2
Application number	US-201715405603-A
Country	US
Kind code	B2
Filing date	Jan 13, 2017
Priority date	Jul 6, 2012
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

A method of manufacturing a MEMS chip includes: providing a silicon substrate layer, the silicon substrate layer comprising a front surface configured to perform a MEMS process and a rear surface opposite to the front surface; growing a first oxidation layer mainly made of SiO 2 on the rear surface of the silicon substrate layer by performing a thermal oxidation process; and depositing a first thin film layer mainly made of silicon nitride on the first oxidation layer by performing a low pressure chemical vapor deposition process.

First claim

What is claimed is:

1. A method of manufacturing a MEMS chip, comprising:
providing a silicon substrate layer, the silicon substrate layer comprising a front surface for a MEMS process and a rear surface opposite to the front surface;
growing a first oxidation layer mainly made of SiO 2 on the rear surface of the silicon substrate layer by performing a thermal oxidation process;
depositing a first thin film layer mainly made of silicon nitride on the first oxidation layer by performing a low pressure chemical vapor deposition process;
growing a second oxidation layer mainly made of SiO 2 on the front surface of the silicon substrate layer by performing a thermal oxidation process;
wherein a ratio of a thickness of the first oxidation layer to a thickness of the first thin film layer ranges from 3 to 4.

2. The method according to claim 1 , wherein the thickness of the first oxidation layer is 400 nm, the thickness of the first thin film layer is 100 nm, a thickness of the second oxidation layer is 100 nm.

3. The method according to claim 1 , further comprising:
depositing a second thin film layer mainly made of silicon nitride on the second oxidation layer by performing a low pressure chemical vapor deposition process, wherein the second oxidation layer has the same thickness as that of the first oxidation layer, the second thin film layer has the same thickness as that of the first thin film layer.

4. The method of claim 1 , wherein the silicon substrate layer is high purity silicon.

Assignees

• Csmc Technologies Fab1 Co Ltd

Inventors

• Dai Dan
• Zhang Xinwei
• Zhou Guoping
• Xia Changfeng

Classifications

• B81C1/00825 Primary

  Protect against mechanical threats, e.g. against shocks, or residues (B81C1/00261 take precedence) · CPC title

• B81C2201/0167

  by adding further layers of materials having complementary strains, i.e. compressive or tensile strain · CPC title

• B81C2201/053

  Depositing a protective layers · CPC title

• B81B7/0029 Primary

  Protection against environmental influences not provided for in groups B81B7/0012 - B81B7/0025 · CPC title

• B81C1/0038

  Processes for creating layers of materials not provided for in groups B81C1/00357 - B81C1/00373 · CPC title