Micro-mirror element

• US 6,906,849 B1
• Filed: 09/23/2004
• Issued: 06/14/2005
• Est. Priority Date: 05/14/2004
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Soneda, Hiromitsu, Mi, Xiaoyu, Ueda, Satoshi, Sawaki, Ippei
• Primary Examiner(s): Ben, Loha
• Application Number:
  US10/711,516
• Time in Patent Office: 264 Days
• Field of Search: 359/290, 359/291, 359/214, 359/222, 359/223, 359/224, 359/230, 359/877, 735/040.2, 735/040.4, 735/041.2, 735/041.4, 735/040.9, 735/141.7, 257/415, 257/418, 257/420
• US Class Current: 359/291
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81B 7/0006 Interconnects
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A micro-mirror element includes a micro-mirror substrate, a wiring substrate and an electroconductive spacer disposed between the two substrates. The micro-mirror substrate is formed integral with a frame, a moving portion having a mirror portion, and a torsion bar connecting the frame to the moving portion. The wiring substrate is provided with a wiring pattern. The electroconductive spacer separates the micro-mirror substrate from the wiring substrate and also electrically connects the frame to the wiring pattern. The wiring substrate has a surface that faces the micro-mirror substrate. A detector is provided on this surface for detecting the pivot angle of the mirror portion.

Claims

1. A micro-mirror element comprising:

a micro-mirror substrate formed integral with at least one micro-mirror unit that includes a frame, a moving portion having a mirror portion, and a torsion bar connecting the frame to the moving portion;

a wiring substrate formed with a wiring pattern; and

an electroconductive spacer for separating the micro-mirror substrate from the wiring substrate and for electrically connecting the frame to the wiring pattern;

wherein the wiring substrate includes a first surface facing the micro-mirror substrate, the first surface being provided with a detector for detecting a pivot angle of the mirror portion.

2. The micro-mirror element according to claim 1, wherein the micro-mirror substrate is formed integral with a plurality of micro-mirror units each of which includes a frame, a moving portion having a mirror portion, and a torsion bar connecting the frame to the moving portion, and

wherein the first surface of the wiring substrate is provided with a plurality of detectors corresponding to the plurality of micro-mirror units, respectively, each detector detecting a pivot angle of the mirror portion in a corresponding one of the micro-mirror units.

3. The micro-mirror element according to claim 1, wherein the detector comprises an optical sensor.

4. The micro-mirror element according to claim 1, wherein the detector comprises a capacitance-type sensor.

5. The micro-mirror element according to claim 1, wherein the wiring substrate includes a second surface opposite to the first surface, the wiring pattern including a first wiring portion on the first surface and a second wiring portion on the second surface, the wiring substrate being formed with tie connectors penetrating the wiring substrate in the thickness direction for connecting the first wiring portion and the second wiring portion to each other.

6. The micro-mirror element according to claim 5, wherein the tie connectors are made of an electroconductive material selected from a group of metals, semiconductors and electroconductive organic materials.

7. The micro-mirror element according to claim 5, wherein the tie connectors are made by one of plating, CVD, LPCVD and MOCVD.

8. The micro-mirror element according to claim 1, wherein the spacer comprises at least one electroconductive bump.

9. The micro-mirror element according to claim 1, wherein the electroconductive spacer is connected to at least one of the wiring pattern and the frame via an electrode pad.

10. The micro-mirror element according to claim 1, wherein the electroconductive spacer is connected to at least one of the wiring pattern and the frame via an electroconductive adhesive.