Aluminum nitride (AlN) devices with infrared absorption structural layer

Patent metadata

Field	Value
Publication number	US-10294097-B2
Application number	US-201615291599-A
Country	US
Kind code	B2
Filing date	Oct 12, 2016
Priority date	Nov 28, 2012
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A micro-electro-mechanical system device is disclosed. The micro-mechanical system device comprises a first silicon substrate comprising: a handle layer comprising a first surface and a second surface, the second surface comprises a cavity; an insulating layer deposited over the second surface of the handle layer; a device layer having a third surface bonded to the insulating layer and a fourth surface; a piezoelectric layer deposited over the fourth surface of the device layer; a metal conductivity layer disposed over the piezoelectric layer; a bond layer disposed over a portion of the metal conductivity layer; and a stand-off formed on the first silicon substrate; wherein the first silicon substrate is bonded to a second silicon substrate, comprising: a metal electrode configured to form an electrical connection between the metal conductivity layer formed on the first silicon substrate and the second silicon substrate.

First claim

What is claimed is:

1. A method, comprising:
depositing an insulation layer over a silicon handle substrate that comprises a first surface and a second surface, wherein the second surface comprises a cavity and the insulation layer is formed on the second surface of the silicon handle substrate;
bonding a first surface of a semiconductor layer to the insulation layer;
depositing a piezoelectric layer directly on a second surface of the semiconductor layer;
depositing a metal conductivity layer over the piezoelectric layer;
partially depositing a bond layer over the metal conductivity layer;
forming a stand-off on the second surface of the semiconductor layer; and
establishing an electrical connection between the metal conductivity layer and a second silicon substrate.

2. The method of claim 1 , further comprising depositing a silicon layer or a silicon dioxide layer to form the stand-off.

3. The method of claim 1 , further comprising depositing a silicon dioxide layer to form a stand-off positioned on the piezoelectric layer.

4. The method of claim 1 , further comprising performing patterning and etching of the piezoelectric layer to form a sidewall.

5. The method of claim 4 , further comprising interposing a first dielectric layer between the piezoelectric layer and the metal conductive layer.

6. The method of claim 5 , further comprising disposing a second dielectric layer on the sidewall of the piezoelectric layer.

7. The method of claim 6 , further comprising exposing the semiconductor layer via a first opening in the silicon handle substrate.

8. The method of claim 7 , further comprising exposing the piezoelectric layer through the first opening and a second opening in the semiconductor layer.

9. The method of claim 1 , further comprising selectively removing a portion of the semiconductor layer.

10. The method of claim 1 , further comprising depositing an infra-red (IR) absorption layer on a selected portion of the semiconductor layer.

11. The method of claim 1 , further comprising depositing an infra-red (IR) absorption layer on a selected portion of the piezoelectric layer.

Assignees

• Invensense Inc

Inventors

• Tsai Julius Ming-Lin
• Daneman Michael J

Classifications

• B81B2201/032

  Bimorph and unimorph actuators, e.g. piezo and thermo · CPC title

• B81B2207/07

  Interconnects · CPC title

• B81B7/007 Primary

  Interconnections between the MEMS and external electrical signals · CPC title

• B81B3/0029

  Transducers for transforming light into mechanical energy or viceversa · CPC title

• B81B2207/012

  the micromechanical device and the control or processing electronics being separate parts in the same package · CPC title