MEMS element, GLV device, and laser display

• US 7,016,099 B2
• Filed: 07/08/2002
• Issued: 03/21/2006
• Est. Priority Date: 07/06/2001
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Ikeda, Koichi, Shimada, Takashi
• Primary Examiner(s): Schwartz, Jordan
• Assistant Examiner(s): STULTZ, JESSICA T
• Application Number:
  US10/189,416
• Publication Number:
  US 20040004592A1
• Time in Patent Office: 1,352 Days
• Field of Search: 359298- 9, 359290- 2, 359/295, 359/302, 359315- 6, 359/318, 359/254, 359/247, 359/259, 359/263, 359/291
• US Class Current: 359/291
• CPC Class Codes: G02B 26/0808 by means of one or more diffracting elements
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A MEMS element is constituted as a light modulation element for constituting a GLV device, and it has the same constitution as a conventional MEMS element except for differing in the structure of a bridge member of a membrane. The membrane comprises SiN film of, for example, 100 nm in thickness laminated thereon, and a combined light reflective film and membrane-side electrode composed of an Al film of 100 nm in thickness provided on the bridge member. The SiO₂ film may be a SiO₂ film formed by thermal oxidation of a sacrificing layer formed of polysilicon or may be a SiO₂ film formed by a CVD method or a PVD method.

Claims

1. A micro electromechanical system element that functions as a light modulation element for modulating the intensity of reflected light by driving a membrane-side electrode through an electrostatic attracting force or an electrostatic repulsion force acting between the membrane-side electrode and a substrate-side electrode, the micro electro-mechanical system element comprising:

a substrate;

the substrate-side electrode;

a bridge member; and

the membrane-side electrode, wherein;

said bridge member includes a nitride film and an oxide film, said oxide film being between said substrate and said nitride film,

a first portion of said bridge member is between said membrane-side electrode and a void,

said substrate-side electrode is between said void and a first portion of said substrate, and

a second portion of said bridge member is in contact with a second portion of said substrate.

2. A micro electromechanical system element as set forth in claim 1, wherein:

said bridge member includes another oxide film, said nitride film being between said oxide film and said another oxide film.

3. A micro electromechanical system element as set forth in claim 1, wherein:

said substrate is an insulating substrate,

said membrane-side electrode is a light-reflective metallic film,

said nitride film is an SiN film, and

said oxide film is any of a silicon oxide (SiO₂) film, a titanium oxide (TiO₂) film, and a zirconium oxide (ZrO₂) film.

4. A grating light valve device comprising:

a plurality of micro electromechanical system elements constituted respectively as light modulation elements and disposed in parallel to each other, wherein;

each of said micro electromechanical system elements comprises the micro electro-mechanical system element of claim 1.