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US5789264A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for manufacturing a thin film actuated mirror having a flat light reflecting surface

Assignee: WiniaDaewoo Co Ltd
•
Filing: 1996-09-23
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Granted: 1998-08-04
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Expires: 2016-09-23
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Abstract

Abstract An inventive method for the manufacture of an array of thin film actuated mirrors includes the steps of: providing an active matrix; forming a plurality of insulating layers having a planarized top surface on top of the active matrix; forming a thin film sacrificial layer having an array of empty cavities on the planarized top surface of the plurality of insulating layers; forming an array of actuating structures on top of the thin film sacrificial layer including the empty cavities, each of the actuating structures including a first thin film electrode, a thin film electrodisplacive member, a second thin film electrode, an elastic member and a conduit; and removing the thin film sacrificial layer, thereby forming the array of thin film actuated mirrors. Since the thin film layers constituting each of the actuating structures are formed on the planarized top surface of the insulating layers, the thin film layers constituting each of the actuating structures are flat, allowing the first thin film electrode placed on top thereof, which also acts as a mirror, to have a flat top surface, thereby increasing the overall optical efficiency and performance of the array.

Inventors

  • 👤 Jae-Hyuk Chung

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 16:17
CPC Classifications
B; B81; B81C; B81C1/00; B81C1/00015; B81C1/00214; B81B; B81B3/00; B81B3/0064; B81B3/0083; G; G02; G02B; G02B26/00; G02B26/08; G02B26/0816; G02B26/0833; G02B26/0858; B81B2201/00; B81B2201/04; B81B2201/042; B81B2203/00; B81B2203/03; B81B2203/0315; B81B2203/04; B81C2201/00; B81C2201/01; B81C2201/0101; B81C2201/0102; B81C2201/0105; B81C2201/0109; B81C2201/0128; B81C2201/013; B81C2201/0135; B81C2201/014; B81C2201/016

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 148 words
A method for the manufacture of an array of thin film actuated mirrors for use in an optical projection system, the method comprising the steps of: providing an active matrix; depositing a passivation layer on top of the active matrix, wherein the passivation layer has a top surface; planarizing the top surface of the passivation layer; depositing an etchant stopping layer on the planarized top surface of the passivation layer; forming a thin film sacrificial layer having an array of empty cavities on top of the etchant stopping layer; forming an array of actuating structures on top of the thin film sacrificial layer including the empty cavities, each of the actuating structures including a first thin film electrode, a thin film electrodisplacive member, a second thin film electrode and an elastic member; and removing the thin film sacrificial layer, thereby forming the array of thin film actuated mirrors.
Claim 2
Independent Claim 148 words
A method for the manufacture of an array of thin film actuated mirrors for use in an optical projection system, the method comprising the steps of: providing an active matrix; depositing a passivation layer on top of the active matrix, wherein the passivation layer has a top surface; planarizing the top surface of the passivation layer; depositing an etchant stopping layer on the planarized top surface of the passivation layer; forming a thin film sacrificial layer having an array of empty cavities on top of the etchant stopping layer; forming an array of actuating structures on top of the thin film sacrificial layer including the empty cavities, each of the actuating structures including a first thin film electrode, a thin film electrodisplacive member, a second thin film electrode and an elastic member; and removing the thin film sacrificial layer, thereby forming the array of thin film actuated mirrors.
Claim 3
Dependent Claim 15 words
The method of claim 1, wherein the passivation layer is made of phosphor-silicate glass (PSG).
Claim 4
Dependent Claim 15 words
The method of claim 1, wherein the passivation layer is made of borophosphor-silicate glass (BPSG).
Claim 5
Dependent Claim 17 words
The method of claim 1, wherein the passivation layer is deposited in a thickness of 2-3 μm.
Claim 6
Dependent Claim 21 words
The method of claim 1, wherein the passivation layer is deposited by using an atmospheric pressure chemical vapor deposition (APCVD) method.
Claim 7
Dependent Claim 23 words
The method of claim 1, wherein the top surface of the passivation layer is planarized by using a chemical mechanical polishing (CMP) method.
Claim 8
Independent Claim 152 words
A method for the manufacture of an array of thin film actuated mirrors for use in an optical projection system, the method comprising the steps of: providing an active matrix; depositing a passivation layer on top of the active matrix, the passivation layer having a top surface; depositing a planarization layer on the top surface of the passivation layer; removing the planarization layer while planarizing the top surface of the passivation layer; forming a thin film sacrificial layer having an array of empty cavities on the planarized top surface of the passivation layer; forming an array of actuating structures on top of the thin film sacrificial layer including the empty cavities, each of the actuating structures including a first thin film electrode, a thin film electrodisplacive member, a second thin film electrode and an elastic member; and removing the thin film sacrificial layer, thereby forming the array of thin film actuated mirrors.
Claim 9
Independent Claim 152 words
A method for the manufacture of an array of thin film actuated mirrors for use in an optical projection system, the method comprising the steps of: providing an active matrix; depositing a passivation layer on top of the active matrix, the passivation layer having a top surface; depositing a planarization layer on the top surface of the passivation layer; removing the planarization layer while planarizing the top surface of the passivation layer; forming a thin film sacrificial layer having an array of empty cavities on the planarized top surface of the passivation layer; forming an array of actuating structures on top of the thin film sacrificial layer including the empty cavities, each of the actuating structures including a first thin film electrode, a thin film electrodisplacive member, a second thin film electrode and an elastic member; and removing the thin film sacrificial layer, thereby forming the array of thin film actuated mirrors.
Claim 10
Dependent Claim 17 words
The method of claim 7, wherein the planarization layer is deposited by using a spin coating method.
Claim 11
Dependent Claim 15 words
The method of claim 8, wherein the planarization layer is made of a viscous polymer.
Claim 12
Dependent Claim 25 words
The method of claim 7, wherein the planarization layer is removed while planarizing the top surface of the passivation layer by using a CMP method.
Claim 13
Dependent Claim 26 words
The method of claim 7, wherein the planarization layer is removed while planarizing the top surface of the passivation layer by using an etch back method.
Claim 14
Dependent Claim 31 words
The method of claim 11, wherein the etch back method for planarizing the top surface of the passivation layer is a plasma etching method employing CF 4 and O 2 plasma.

References Cited (Backward Citations)

US4259779A Cited
US4692994A Cited
US5550680A Cited
US5481396A Cited
US5589084A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-08-03 2002-02-02 2002-08-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-08-03 2006-02-02 2006-08-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-08-03 2010-02-02 2010-08-04 $7700.00 Window Closed / Lapsed

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