MEMS SENSOR AND METHOD OF MANUFACTURING THE SAME

• US 20100116057A1
• Filed: 05/16/2008
• Published: 05/13/2010
• Est. Priority Date: 05/17/2007
• Status: Abandoned Application

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Nakatani, Goro
• Application Number:
  US12/451,497
• Publication Number:
  US 20100116057A1
• Time in Patent Office: Days
• US Class Current: 73/514.330
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2203/0118 Cantilevers
• CPC Class Codes: B81C 1/00476 removing a sacrificial layer B81C1/00912 takes precedence
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/123 by piezo-resistive elements, e.g. semiconductor strain gauges
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01P 2015/0842 the mass being of clover leaf shape
• CPC Class Codes: H01L 29/84 controllable by variation of applied mechanical force, e.g. of pressure
• CPC Class Codes: Y10T 29/49156 with selective destruction of conductive paths

Abstract

An MEMS (Micro Electro Mechanical Systems) sensor includes a base layer and a deformation portion provided on the base layer at an interval from the base layer and deformed by external force. The deformation portion is made of an organic material.

Claims

1. A MEMS sensor comprising:

a base layer; and

a deformation portion provided on the base layer at an interval from the base layer and deformed by external force, wherein

the deformation portion is made of an organic material.

2. MEMS sensor according to claim 1, comprising a weight provided on a surface of the deformation portion opposed to the base layer.

3. MEMS sensor according to claim 2, wherein

the weight is made of the organic material, and integrally formed with the deformation portion.

4. MEMS sensor according to claim 3, wherein the organic material is polyimide.

5. MEMS sensor according to claim 2, comprising:

a frame supporting the deformation portion on the periphery of the weight;

a resistive conductor arranged on the deformation portion; and

a wire arranged on the deformation portion and connected to the resistive conductor.

6. MEMS sensor according to claim 1, comprising:

a first electrode provided on a surface of the base layer opposed to the deformation portion; and

a second electrode provided on a surface of the deformation portion opposed to the base layer and opposed to the first electrode at an interval.

7. MEMS sensor according to claim 6, comprising a protrusion provided on the surface of the deformation portion opposed to the base layer.

8. MEMS sensor according to claim 7, wherein

the protrusion is made of the organic material, and integrally formed with the deformation portion.

9. MEMS sensor according to claim 8, wherein

the organic material is polyimide.

10. A method of manufacturing a MEMS sensor, comprising the steps of :

forming a sacrificial layer on a base layer;

forming a recess in the surface of the sacrificial layer;

forming an organic material layer to fill up the recess and to cover the surface of the sacrificial layer;

forming a wire on the organic material layer;

forming a resistive conductor connected with the wire on the organic material layer;

forming a groove along the periphery of the recess in plan view by etching the organic material layer from the surface side of the organic material layer; and

forming a beam and a weight consisting of the organic material layer by etching the sacrificial layer through the groove.

11. A method of manufacturing a MEMS sensor, comprising the steps of:

forming a first electrode made of a first conductive material on a base layer;

forming a sacrificial layer made of a material different from the first conductive material on the first electrode;

forming a second electrode made of a second conductive material identical to or different from the first conductive material on the sacrificial layer;

forming an organic material layer made of an organic material on the second electrode;

forming a through-hole penetrating the organic material layer and the second electrode in the stacking direction thereof; and

forming a space between the first electrode layer and the second electrode by etching the sacrificial layer through the through-hole.