Method and structure for adding mass with stress isolation to MEMS structures

Patent metadata

Field	Value
Publication number	US-9321629-B2
Application number	US-201414217376-A
Country	US
Kind code	B2
Filing date	Mar 17, 2014
Priority date	Jun 23, 2009
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

A method and structure for adding mass with stress isolation to MEMS. The structure has a thickness of silicon material coupled to at least one flexible element. The thickness of silicon material can be configured to move in one or more spatial directions about the flexible element(s) according to a specific embodiment. The apparatus also includes a plurality of recessed regions formed in respective spatial regions of the thickness of silicon material. Additionally, the apparatus includes a glue material within each of the recessed regions and a plug material formed overlying each of the recessed regions.

First claim

What is claimed is:

1. A method for fabricating a MEMS (micro-electro-mechanical-system) structure including a proof mass apparatus, the method comprising:
providing a thickness of silicon material coupled to at least one flexible element, the thickness of silicon material being configured to move in one or more spatial directions about the flexible element(s);
forming one or more stress isolation regions in thickness of silicon material in a vicinity of the flexible element;
forming a plurality of recessed regions in respective spatial regions of the thickness of silicon material adjacent the stress isolation regions;
forming a glue material within each of the recessed regions; and
forming a plug material overlying each of the recessed regions;
wherein a proof mass is configured from at least the plug material provided in each of the plug regions in the thickness of silicon material.

2. The method of claim 1 wherein the plurality of recessed regions are configured as an array.

3. The method of claim 1 wherein each of the recessed regions is characterized by an aspect ratio of greater than five to one.

4. The method of claim 1 wherein the glue material comprises titanium nitride material.

5. The method of claim 1 wherein the glue material includes at least titanium material, platinum material, cobalt material, tantalum material, tungsten material, or nitride material.

6. The method of claim 1 wherein the plug material comprises tungsten material.

7. The method of claim 1 wherein the proof mass is an inertial weight.

8. The method of claim 1 further comprising at least one stress isolation region configured within a vicinity of the flexible element(s).

9. The method of claim 1 wherein the thickness of silicon material and the flexible element(s) are provided on a thickness of silicon material.

10. The method of claim 1 further comprising at least one stress isolation region pattern from at least one portion of the thickness of silicon material.

11. The method of claim 10 wherein the stress isolation region pattern comprises one or more isolation cavity regions.

12. A method for adding mass with stress isolation to a MEMS (micro-electro-mechanical-system) structure, the method comprising:
providing a thickness of silicon material coupled to at least one flexible element, the thickness of silicon material being configured to move in one or more spatial directions about the flexible element(s);
forming one or more stress isolation regions in a vicinity of the flexible element(s);
forming a plurality of recessed regions in respective spatial regions of the thickness of silicon material adjacent to the stress isolation regions;
forming a glue material within one or more of the recessed regions; and
forming a plug material overlying one or more of the recessed regions;
wherein a proof mass is configured from at least the plug material provided in each of the plug regions.

13. The method of claim 12 wherein the stress isolation region comprises one or more isolation cavity regions.

14. A method for adding mass with stress isolation to a MEMS (micro-electro-mechanical-system) structure, the method comprising:
providing a thickness of silicon material coupled to at least one flexible element which is attached to a MEMS structure, the thickness of silicon material being configured to move in one or more spatial directions about the flexible element(s);
forming one or more stress isolation regions in a vicinity of the flexible element(s);
forming a plurality of recessed regions in respective spatial regions of the thickness of silicon material adjacent to the stress isolation regions;
forming a glue material within one or more of the recessed regions; and
forming a plug material overlying one or more of the recessed regions;
wherein a proof mass is configured from at least the plug material provided in each of the plug regions.

15. The method of claim 14 wherein the stress isolation region comprises one or more isolation cavity regions.

Assignees

• Mcube Inc

Inventors

• Koury Jr Daniel N

Classifications

• H10F39/18

  Complementary metal-oxide-semiconductor [CMOS] image sensors; Photodiode array image sensors · CPC title

• H10F39/803

  Pixels having integrated switching, control, storage or amplification elements · CPC title

• B81C1/00134 Primary

  comprising flexible or deformable structures (manufacture of MEMS devices for specific applications, see relevant places, e.g. gyroscopes G01C19/5719, pressure sensors G01L9/0042, accelerometers G01P15/0802, acoustic transducers or diaphragms therefor H04R31/00) · CPC title

• H01L27/14643

  Electricity · mapped topic

• B81C1/00142 Primary

  Bridges (deformable micromirrors G02B26/0841) · CPC title