Mirror Device, Mirror Array, Optical Switch, Mirror Device Manufacturing Method, and Mirror Substrate Manufacturing Method

• US 20080100899A1
• Filed: 12/28/2005
• Published: 05/01/2008
• Est. Priority Date: 01/05/2005
• Status: Active Grant

• Current Assignee: Nippon Telegraph and Telephone Corporation
• Original Assignee: Nippon Telegraph and Telephone Corporation
• Inventors: Morita, Hirofumi, Inagaki, Shuichiro, Shimokawa, Fusao, Uchiyama, Shingo, Sato, Makoto, Ishii, Hiromu, Sasakura, Kunihiko, Yamaguchi, Johji, Machida, Katsuyuki
• Granted Patent: US 8,149,489 B2
• Time in Patent Office: Days
• US Class Current: 359/225
• CPC Class Codes: B81B 2201/045 Optical switches
• CPC Class Codes: B81B 2203/058 Rotation out of a plane parallel to the substrate
• CPC Class Codes: B81B 3/004 Angular deflection
• CPC Class Codes: B81B 3/0086 Electrical characteristics, e.g. reducing driving voltage, improving resistance to peak voltage
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 6/3518 the reflective optical element being an intrinsic part of a MEMS device, i.e. fabricated together with the MEMS device MEMS devices in general B81B; manufacture of MEM devices in general B81C; micromechanical devices controlling the direction of light G02B26/0833
• CPC Class Codes: G02B 6/3556 NxM switch, i.e. regular arrays of switches elements of matrix type constellation
• CPC Class Codes: G02B 6/3584 constructional details of an associated actuator having a MEMS construction, i.e. constructed using semiconductor technology such as etching MEMS per se B81B, B81C
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 29/49885 with coating before or during assembling

Abstract

A mirror device includes a mirror (153) which is supported to be pivotable with respect to a mirror substrate (151), a driving electrode (103-1-103-4) which is formed on an electrode substrate (101) facing the mirror substrate, and an antistatic structure (106) which is arranged in a space between the mirror and the electrode substrate. This structure can fix the potential of the lower surface of the mirror and suppress drift of the mirror by applying a second potential to the antistatic structure.

Claims

1. A mirror device characterized by comprising:

a mirror which is supported to be pivotable with respect to a mirror substrate;

a driving electrode which is formed on an electrode substrate facing said mirror substrate; and

an antistatic structure which is arranged in a space between said mirror and said electrode substrate.

2. A mirror device according to claim 1, characterized in that said driving electrode controls a tilt angle of said mirror.

3. A mirror device according to claim 2, characterized by further comprising a power supply which applies a first potential to said driving electrode,

wherein said antistatic structure covers an insulating material that exists in the space with a metal material equipotential to said mirror or removes the insulating material.

4. A mirror device according to claim 3, characterized in that said mirror substrate electrically connects to said electrode substrate.

5. A mirror device according to claim 3, characterized by further comprising a first metal layer which is formed, as said antistatic structure, on a surface of said mirror facing said driving electrode,

wherein said power supply applies a second potential to said first metal layer and said mirror substrate.

6. A mirror device according to claim 3, characterized in that

said mirror substrate and said electrode substrate, which have conductivity serve as said antistatic structure, and

said power supply applies a second potential to said mirror and said electrode substrate.

7. A mirror device according to claim 3, characterized in that an opening is formed, as said antistatic structure, in an insulating layer that covers said driving electrode.

8. A mirror device according to claim 3, characterized by further comprising a second metal layer which is formed, as said antistatic structure, around said driving electrode on said electrode substrate,

wherein said power supply applies a second potential to said mirror and said second metal layer.

9. A mirror device according to claim 8, characterized by further comprising an interconnection which connects said second metal layer to said power supply.

10. A mirror device according to claim 9, characterized in that said interconnection is formed on said electrode substrate.

11. A mirror device according to claim 9, characterized in that said interconnection is formed between said electrode substrate and said second metal layer.

12. A mirror device according to claim 1, characterized in that

said electrode substrate comprises:

a substantially conical projecting portion which is formed from a base with an interconnection and faces said mirror; and

a trench which is formed in the base around said projecting portion, and

said driving electrode is formed at least on surfaces of said projecting portion and the trench to electrically connect to the interconnection.

13. A mirror device according to claim 12, characterized in that the trench includes:

a first trench formed in the base; and

a second trench formed in a bottom portion of the first trench.

14. A mirror device according to claim 12, characterized in that the trench includes a plurality of trenches.

15. A mirror device according to claim 1, characterized in that said electrode substrate further comprises a fulcrum projection which faces said mirror and is formed at an arbitrary position on said electrode substrate different from a position where a center of said mirror is projected onto said electrode substrate.

16. A mirror device according to claim 15, characterized by further comprising a projecting portion which projects from said electrode substrate and has a flat surface on an upper side,

wherein said driving electrode is formed on surfaces of said electrode substrate and said projecting portion, and

said fulcrum projection is formed on the flat surface.

17. A mirror device according to claim 1, characterized by further comprising a pair of connection members which connect said mirror to said mirror substrate,

said connection members having different spring constants.

18. A mirror device according to claim 17, characterized in that

said connection members include a pair of first connection members and a pair of second connection members, and

said mirror substrate has a first opening and

comprises a movable frame which connects to said mirror substrate through said first connection members to be pivotally supported in the first opening and has a second opening to pivotally support, in the second opening, said mirror connected through said second connection members.

19. A mirror device according to claim 18, characterized in that said mirror substrate has a notch to accommodate the first connection member.

20. A mirror device according to claim 18, characterized in that said movable frame has a notch to accommodate the first connection member.

21. A mirror device according to claim 18, characterized in that said movable frame has a notch to accommodate the second connection member.

22. A mirror device according to claim 1, characterized in that said driving electrode is formed at an arbitrary position on said electrode substrate asymmetrically with respect to a pivot axis of said mirror projected onto said electrode substrate.

23. A mirror device according to claim 22, characterized in that said driving electrode is divided by a parting line parallel to the pivot axis of said mirror.

24. A mirror device according to claim 22, characterized by further comprising a substantially conical projecting portion which projects from said electrode substrate,

wherein said driving electrode is formed on surfaces of said electrode substrate and said projecting portion.

25. A mirror device according to claim 24, characterized in that said projecting portion is formed at an arbitrary position on said electrode substrate asymmetrically with respect to a pivot axis of said mirror projected onto said electrode substrate.

26. A mirror device according to claim 1, characterized in that a pivot axis of said mirror does not pass through a gravity center of said mirror.

27. A mirror device according to claim 26, characterized by further comprising a pair of connection members which connect said mirror to said mirror substrate.

28. A mirror device according to claim 27, characterized in that

said connection members include a pair of first connection members and a pair of second connection members, and

said mirror substrate has a first opening and

comprises a movable frame which connects to said mirror substrate through said first connection members to be pivotally supported in the first opening and has a second opening to pivotally support, in the second opening, said mirror connected through said second connection members.

29. A mirror device according to claim 28, characterized in that

the pivot axis of said mirror includes a first pivot axis by said pair of first connection members and a second pivot axis by said pair of second connection members, and

at least one of the first pivot axis and the second pivot axis does not pass through the gravity center of said mirror.

30. A mirror device according to claim 28, characterized in that said mirror substrate has a notch to accommodate the first connection member.

31. A mirror device according to claim 28, characterized in that said movable frame has a notch to accommodate the first connection member.

32. A mirror device according to claim 1, characterized by further comprising an interconnection which connects to said driving electrode and is arranged on said electrode substrate while intersecting a pivot axis of said mirror at a right angle.

33. A mirror device according to claim 32, characterized by further comprising:

an annular gimbal which is supported to be pivotable with respect to said mirror substrate; and

an interconnection which connects to said driving electrode and is arranged on said electrode substrate while intersecting a pivot axis of said gimbal at a right angle,

wherein said mirror is provided inside said gimbal and supported to be pivotable with respect to said gimbal.

34. A mirror device according to claim 1, characterized by further comprising:

an interconnection which is formed on said electrode substrate to supply a driving voltage to said driving electrode; and

a conductive member which is equipotential to said mirror and arranged at a position closer to said interconnection than said mirror.

35. A mirror device according to claim 34, characterized in that

said driving electrode and said interconnection are formed on an insulating layer on said electrode substrate having conductivity, and

said electrode substrate comprises a conductive member equipotential to said mirror.

36. A mirror device according to claim 35, characterized by further comprising a conductive layer which is formed on an insulating layer on said interconnection as a conductive member equipotential to said mirror.

37. A mirror device according to claim 35, characterized by further comprising a conductive wall-shaped member which is arranged on said electrode substrate between said mirror and said interconnection as a conductive member equipotential to said mirror.

38. A mirror device according to claim 1, characterized by further comprising:

a pivot which is formed on said electrode substrate to support a pivotal center of said mirror; and

a control circuit which applies a voltage to said driving electrode,

wherein said driving electrode comprises a plurality of driving electrodes formed around said pivot on said electrode substrate, and

said control circuit controls pivotal movement of said mirror by applying a single bias voltage to said plurality of driving electrodes, and simultaneously, individually applying, to each driving electrode, a driving voltage necessary for making said mirror pivot.

39. A mirror device according to claim 38, characterized in that said control circuit comprises:

a storage unit which stores in advance a relationship between a tilt angle of said mirror and the driving voltage applied to each driving electrode;

an acquisition unit which acquires, from said storage unit, a value of the driving voltage necessary for obtaining a desired tilt angle of said mirror in correspondence with each driving electrode; and

a power supply which individually applies, to each driving electrode, a voltage having a value corresponding to a sum of the predetermined bias voltage and the acquired driving voltage for each driving electrode.

40. A mirror device according to claim 38, characterized in that the bias voltage is substantially ½

a maximum value of the voltage applied to said driving electrode.

41. A mirror device according to claim 1, characterized by further comprising:

a control circuit which controls pivotal operation of said mirror by applying, to said driving electrode, a bias voltage, and simultaneously, a driving voltage necessary for making said mirror pivot,

wherein the bias voltage is substantially ½

a maximum value of the voltage applied to said driving electrode.

42. A mirror device according to claim 41, characterized in that

said driving electrode comprises a plurality of driving electrodes formed on said electrode substrate, and

said control circuit applies a single bias voltage to said plurality of driving electrodes.

43. A mirror device according to claim 41, characterized in that

said driving electrode comprises a pair of driving electrodes provided symmetrically with respect to a pivot axis of said mirror, and

said control circuit applies a voltage having a value corresponding to a sum of the bias voltage and the driving voltage to one driving electrode and a voltage having a value corresponding to a difference between the bias voltage and the driving voltage to the other driving electrode.

44. A mirror device according to claim 1, characterized by further comprising a plurality of mirror electrodes which are provided on a surface of said mirror facing said driving electrode.

45. A mirror device according to claim 44, characterized by further comprising a substantially conical projecting portion which is formed on said electrode substrate,

wherein at least part of said driving electrode is formed on said projecting portion.

46. A mirror device according to claim 44, characterized in that

said mirror is supported to be pivotable about a pivot axis passing through a center of said mirror, and

said plurality of mirror electrodes are arranged symmetrically with respect to the center of said mirror.

47. A mirror device according to claim 44, characterized by further comprising a rib structure which is provided around said driving electrode on said electrode substrate,

wherein said mirror substrate is fixed on said rib structure.

48. A mirror device according to claim 44, characterized by further comprising:

a pair of connection members which connect said mirror to said mirror substrate; and

a plurality of interconnections which connect one of said mirror electrodes and pass through at least one of said connection members.

49. A mirror device according to claim 48, characterized in that said interconnections are formed on at least one surface of said mirror substrate.

50. A mirror device according to claim 48, characterized in that said interconnections are stacked on an insulating layer.

51. A mirror device according to claim 48, characterized in that

said connection members include a pair of first connection members and a pair of second connection members, and

said mirror substrate has a first opening and

comprises a movable frame which connects to said mirror substrate through said first connection members to be pivotally supported in the first opening and has a second opening to pivotally support, in the second opening, said mirror connected through said second connection members.

52. A mirror device according to claim 1, characterized in that

said driving electrode is formed from a base of said electrode substrate with an interconnection while facing said mirror and electrically connects to the interconnection,

said electrode substrate comprises rib structures formed to sandwich a region where said electrode is formed, and

said mirror substrate is formed from an SOI substrate including a base portion made of silicon, a buried insulating layer formed on said base portion, and a silicon layer formed on said buried insulating layer,

said mirror substrate comprises:

a base having an opening formed in a mirror formation region of said silicon layer and said mirror which pivotally connects to an inside of the opening of the said base through a pair of connectors;

an opening which is formed in the mirror formation region of said base portion and said buried insulating layer; and

a gap auxiliary layer which is formed on said base of said silicon layer, and

said mirror substrate joins to said rib structures through said gap auxiliary layer.

53. A mirror device according to claim 52, characterized in that

said electrode substrate further comprises a substantially conical projecting portion which is formed from said base while facing said mirror, and

said driving electrode is formed on said projecting portion.

54. A mirror device according to claim 1, characterized by further comprising an elastic member which connects said mirror to said mirror substrate,

wherein said mirror substrate has a first opening,

said mirror is pivotally supported in the first opening by said elastic member, and

letting m be a mass of said mirror, G be an acceleration applied to the mirror device, and k be a spring constant of said elastic member, an interval between said mirror and said elastic member is not less than mG/k.

55. A mirror device according to claim 54, characterized in that

said elastic member includes a pair of first elastic members and a pair of second elastic members,

said mirror substrate comprises a movable frame which connects to said mirror substrate through said first connection members to be pivotally supported in the first opening and has a second opening to pivotally support, in the second opening, said mirror connected through said second connection members, and

letting m1 be a total mass of said mirror and said movable frame, G be the acceleration applied to the mirror device, and k1 be a spring constant of said first elastic member, an interval between said movable frame and said mirror substrate is not less than m1G/k1.

56. A mirror device according to claim 54, characterized in that

said elastic member is arranged in a notch formed in said mirror substrate, and

an interval between an edge of the notch and said elastic member is not less than mG/k.

57. A mirror device according to claim 56, characterized in that

said elastic member includes a pair of first elastic members and a pair of second elastic members,

said mirror substrate comprises a movable frame which connects to said mirror substrate through said first connection members to be pivotally supported in the first opening and has a second opening to pivotally support, in the second opening, said mirror connected through said second connection members,

said first elastic member is arranged in a first notch formed in said mirror substrate, and

letting m1 be a total mass of said mirror and said movable frame, G be the acceleration applied to the mirror device, and k1 be a spring constant of said first elastic member, an interval between an edge of the first notch and said first elastic member is not less than m1G/k1.

58. A mirror device according to claim 56, characterized in that

said elastic member includes a pair of first elastic members and a pair of second elastic members,

said mirror substrate comprises a movable frame which connects to said mirror substrate through said first connection members to be pivotally supported in the first opening and has a second opening to pivotally support, in the second opening, said mirror connected through said second connection members,

said first elastic member is arranged in a second notch formed in said movable frame, and

letting m1 be a total mass of said mirror and said movable frame, G be the acceleration applied to the mirror device, and k1 be a spring constant of said first elastic member, an interval between an edge of the second notch and said first elastic member is not less than m1G/k1.

59. A mirror array characterized by two-dimensionally arraying a plurality of mirror devices, each of the mirror devices comprising:

a mirror which is supported to be pivotable with respect to a mirror substrate;

a driving electrode which is formed on an electrode substrate facing said mirror substrate; and

an antistatic structure which is arranged in a space between said mirror and said electrode substrate.

60. A mirror array according to claim 59, characterized in that

the mirror device further comprises:

an annular gimbal which is supported to be pivotable with respect to said mirror substrate; and

an interconnection which connects to said driving electrode and is arranged on said electrode substrate while intersecting a pivot axis of said gimbal at a right angle,

said mirror is provided inside said gimbal and supported to be pivotable with respect to said gimbal,

when a rectangular mirror arrangement region is divided into four divided regions by two diagonal lines, the mirror devices are arranged such that pivot axes of said gimbals intersect at a right angle in two arbitrary adjacent divided regions which are surrounded by two crossing sides of the mirror arrangement region and the diagonal lines, and

an interconnection connected to said driving electrode is arranged on said electrode substrate perpendicularly to the pivot axis of the gimbal in each divided region.

61. A mirror array according to claim 59, characterized in that

said electrode substrate further comprises a fulcrum projection which faces said mirror and is formed at an arbitrary position on said electrode substrate different from a position where a center of said mirror is projected onto said electrode substrate, and

the arbitrary position is decided in accordance with a position of the mirror device in the mirror array.

62. A mirror array according to claim 59, characterized in that

the mirror device further comprises a pair of connection members which connect said mirror to said mirror substrate, and

a spring constant of said connection member is decided in accordance with a position of the mirror device in the mirror array.

63. A mirror array according to claim 62, characterized in that said connection members have different spring constants.

64. A mirror array according to claim 59, characterized in that

said driving electrode is formed at an arbitrary position on said electrode substrate asymmetrically with respect to a pivot axis of said mirror projected onto said electrode substrate, and

the arbitrary position is decided in accordance with a position of the mirror device in the mirror array.

65. A mirror array according to claim 59, characterized in that

a pivot axis of said mirror does not pass through a gravity center of said mirror, and

a shift amount between the pivot axis of said mirror and the gravity center of said mirror is decided in accordance with a position of the mirror device in the mirror array.

66. An optical switch characterized by comprising:

a first mirror array which reflects light from an input port; and

a second mirror array which reflects the light from said first mirror array and guides the light to an output port,

each of said first mirror array and said second mirror array comprising

a mirror array formed by two-dimensionally arraying a plurality of mirror devices, each of the mirror devices comprising a mirror which is supported to be pivotable with respect to a mirror substrate, a driving electrode which is formed on an electrode substrate facing said mirror substrate, and an antistatic structure which is arranged in a space between said mirror and said electrode substrate.

67. An optical switch according to claim 66, characterized in that

the mirror device further comprises:

an annular gimbal which is supported to be pivotable with respect to said mirror substrate; and

an interconnection which connects to said driving electrode and is arranged on said electrode substrate while intersecting a pivot axis of said gimbal at a right angle,

said mirror is provided inside said gimbal and supported to be pivotable with respect to said gimbal,

when a rectangular mirror arrangement region is divided into four divided regions by two diagonal lines, the mirror devices are arranged such that pivot axes of said gimbals intersect at a right angle in two arbitrary adjacent divided regions which are surrounded by two crossing sides of the mirror arrangement region and the diagonal lines, and

an interconnection connected to said driving electrode is arranged on said electrode substrate perpendicularly to the pivot axis of the gimbal in each divided region.

68. An optical switch according to claim 66, characterized in that

said electrode substrate further comprises a fulcrum projection which faces said mirror and is formed at an arbitrary position on said electrode substrate different from a position where a center of said mirror is projected onto said electrode substrate, and

the arbitrary position is decided in accordance with a position of the mirror device in the mirror array.

69. An optical switch according to claim 66, characterized in that

the mirror device further comprises a pair of connection members which connect said mirror to said mirror substrate, and

a spring constant of said connection member is decided in accordance with a position of the mirror device in the mirror array.

70. An optical switch according to claim 69, characterized in that said connection members have different spring constants.

71. An optical switch according to claim 66, characterized in that

said driving electrode is formed at an arbitrary position on said electrode substrate asymmetrically with respect to a pivot axis of said mirror projected onto said electrode substrate, and

the arbitrary position is decided in accordance with a position of the mirror device in the mirror array.

72. An optical switch according to claim 66, characterized in that

a pivot axis of said mirror does not pass through a gravity center of said mirror, and

a shift amount between the pivot axis of said mirror and the gravity center of said mirror is decided in accordance with a position of the mirror device in the mirror array.

73. An optical switch according to claim 66, characterized in that

said first mirror array has a plurality of first mirrors arranged two-dimensionally, and a first driving electrode which is provided for each of said first mirrors to control a tilt angle of said first mirror,

said second mirror array has a plurality of second mirrors arranged two-dimensionally, and a second driving electrode which is provided for each of said second mirrors to control a tilt angle of said second mirror,

a mirror arrangement region of said first mirror array is set in accordance with anisotropy of the tilt angle of said second mirror decided by a direction of a parting line of said second driving electrode, and

a mirror arrangement region of said second mirror array is set in accordance with anisotropy of the tilt angle of said first mirror decided by a direction of a parting line of said first driving electrode.

74. An optical switch according to claim 73, characterized in that each of said first driving electrode and said second driving electrode includes four divided electrodes formed on a terrace-shaped projecting portion which is formed on a substrate and has a substantially square upper surface when viewed from an upper side, and

four sides of the rectangular mirror arrangement region of said first mirror array intersect the parting lines of said second driving electrode at 45°

, and four sides of the rectangular mirror arrangement region of said second mirror array intersect the parting lines of said first driving electrode at 45°

.

75. An optical switch according to claim 73, characterized in that each of said first driving electrode and said second driving electrode includes four divided electrodes formed on a terrace-shaped projecting portion which is formed on a substrate and has a substantially square upper surface when viewed from an upper side, a direction perpendicular to a pair of opposite sides of the upper surface of the projecting portion is set as a first parting line, and a direction perpendicular to another pair of opposite sides of the upper surface of the projecting portion is set as a second parting line.

76. A method of manufacturing a mirror device which includes a mirror substrate having a flat mirror pivotally supported, and an electrode substrate which faces the mirror substrate and has an electrode to control pivotal movement of the mirror, characterized by comprising:

the first step of preparing the mirror substrate having the flat mirror pivotally supported;

the second step of forming a first metal layer on one surface of the mirror;

the third step of forming a second metal layer on the other surface of the mirror; and

the fourth step of placing the mirror substrate on the electrode substrate to make the electrode face the mirror.

77. A mirror device manufacturing method according to claim 76, characterized in that

in the second step, a thickness of the first metal layer is set in accordance with a shape of the mirror to be formed, and

in the third step, a thickness of the second metal layer is set in accordance with the shape of the mirror to be formed.

78. A mirror device manufacturing method according to claim 76, characterized in that

in the second step, a material of the first metal layer is set in accordance with a shape of the mirror to be formed, and

in the third step, a material of the second metal layer is set in accordance with the shape of the mirror to be formed.

79. A mirror device manufacturing method according to claim 76, characterized by further comprising the fifth step of annealing the mirror substrate after the third step or the fourth step.

80. A mirror device manufacturing method according to claim 76, characterized in that

in the second step, a temperature in forming the first metal layer is set in accordance with a shape of the mirror to be formed, and

in the third step, a temperature in forming the second metal layer is set in accordance with the shape of the mirror to be formed.

81. A method of manufacturing a mirror device which includes a mirror substrate having a mirror pivotally supported, and an electrode substrate which faces the mirror substrate, characterized by comprising:

the first step of preparing the electrode substrate having a flat surface, a substantially conical projecting portion that projects from the flat surface, and a trench formed in the flat surface around the projecting portion;

the second step of forming a metal layer on the flat surface and surfaces of the projecting portion and trench of the electrode substrate;

the third step of patterning the metal layer while setting focus of an exposure apparatus on the flat surface to form an interconnection on the flat surface and, at least on the surfaces of the projecting portion and trench, an electrode connected to the interconnection; and

the fourth step of placing the mirror substrate on the electrode substrate to make the electrode face the mirror.

82. A method of manufacturing a mirror substrate, characterized by comprising at least:

the first step of preparing an SOI substrate including a substrate portion, a buried insulating layer on the substrate portion, and a silicon layer on the buried insulating layer;

the second step of forming a movable portion formation mask pattern on a surface of the silicon layer and forming the silicon layer by etching using the movable portion formation mask pattern as a mask to form, in a mirror formation region on the buried insulating layer, a base and a plate-shaped mirror structure connected to the base through a pair of connectors;

the third step of forming a protective layer that fills spaces between the base, the connectors, and the mirror structure; and

the fourth step of forming, on a surface of the substrate portion, a frame formation mask pattern with an opening corresponding to the mirror formation region and removing the substrate portion and the buried insulating layer by etching using the frame formation mask pattern as a mask to expose the silicon layer on a side of the substrate portion in the mirror formation region and form a frame portion outside the mirror formation region.

83. A mirror substrate manufacturing method according to claim 82, characterized by further comprising the fifth step of forming a metal film on a surface of the mirror structure on a side where the frame portion is formed.

84. A mirror substrate manufacturing method according to claim 82, characterized by further comprising the step of removing the protective layer at least after formation of the frame portion.

85. A mirror device manufacturing method characterized by comprising at least the step of bonding an electrode substrate with an electrode to a mirror substrate formed by a mirror substrate manufacturing method of claim 82 to form a mirror device having the electrode facing the mirror structure,

wherein the mirror device is accommodated in a package and fixed, and a terminal of the package is wire-bonded to a terminal of the electrode substrate.

86. A mirror device manufacturing method according to claim 85, characterized by further comprising the steps of:

before bonding the electrode substrate to the mirror substrate, forming a metal film on a surface of the mirror structure on a side where the frame portion is formed; and

after bonding the electrode substrate to the mirror substrate, removing the protective layer.