Microelectromechanical (MEMS) switching apparatus

• US 20050007219A1
• Filed: 08/04/2004
• Published: 01/13/2005
• Est. Priority Date: 07/11/2002
• Status: Active Grant

• Current Assignee: Dong Shim, John Heck, Li-Peng Wang, Qing Ma, Quan Tran, Valluri Rao
• Original Assignee: Dong Shim, John Heck, Li-Peng Wang, Qing Ma, Quan Tran, Valluri Rao
• Inventors: Heck, John, Shim, Dong, Wang, Li-Peng, Ma, Qing, Rao, Valluri, Tran, Quan
• Granted Patent: US 6,967,548 B2
• Time in Patent Office: Days
• US Class Current: 335/78
• CPC Class Codes: H01H 2001/0078 with parallel movement of the movable contact relative to the substrate
• CPC Class Codes: H01H 2059/0036 Movable armature with higher resonant frequency for faster switching
• CPC Class Codes: H01H 59/0009 making use of micromechanics

Abstract

This application discloses a microelectromechanical (MEMS) switch apparatus comprising an anchor attached to a substrate and an electrically conductive beam attached to the anchor and in electrical contact therewith. The beam comprises a tapered portion having a proximal end and a distal end, the proximal end being attached to the anchor, an actuation portion attached to the distal end of the tapered portion, a tip attached to the actuation portion, the tip having a contact dimple thereon. The switch apparatus also includes an actuation electrode attached to the substrate and positioned between the actuation portion and the substrate. Additional embodiments are also described and claimed.

Claims

1-48. -48. (cancelled)

49. A method comprising:

forming an actuation electrode over a portion of a substrate;

forming an electrode over a second portion of the substrate;

forming an anchor over a third portion of the substrate;

forming an electrically conductive beam attached to the anchor;

forming an actuation portion attached to the beam and positioned opposite the actuation electrode;

forming a tip attached to the actuation portion; and

forming a contact dimple attached to the tip.

50. The method of claim 49, wherein a portion of the beam attached to the anchor is wider than a portion of the beam attached to the actuation portion.

51. The method of claim 49, wherein the beam is comprised of gold (Au).

52. The method of claim 49, further comprising:

providing a charge in the actuation electrode to draw the contact dimple into contact with the electrode.

53. A method comprising:

forming a signal line over a portion of a substrate;

forming a first actuation electrode over a second portion of the substrate;

forming a first anchor over a third portion of the substrate;

forming a first electrically conductive beam attached to the first anchor;

forming a first actuation portion attached to the first beam and positioned opposite the first actuation electrode;

forming a first tip attached to the first actuation portion; and

forming a first contact dimple attached to the first tip and opposite the signal line.

54. The method of claim 53 further comprising:

forming a second actuation electrode over a fourth portion of a substrate;

forming a second anchor over a fifth portion of the substrate;

forming a second electrically conductive beam attached to the second anchor;

forming a second actuation portion attached to the second beam and positioned opposite the second actuation electrode;

forming a second tip attached to the second actuation portion; and

forming a second contact dimple attached to the second tip and opposite the signal line.

55. The method of claim 54, wherein a portion of the first beam attached to the first anchor is wider than a portion of the first beam attached to the first actuation portion.

56. The method of claim 54, wherein a portion of the second beam attached to the second anchor is wider than a portion of the second beam attached to the second actuation portion.

57. The method of claim 54, wherein each of the beams is comprised of gold (Au).

58. The method of claim 54, further comprising:

coupling each of the anchors to ground;

shunting a signal traveling through the signal line to ground.

59. The method of claim 58, wherein the shunting comprises:

drawing the first and second contact dimples into contact with the signal line by inducing an electrical charge in the first and second actuation electrodes.

60. A method comprising:

forming a first signal line over a portion of a substrate;

forming a second signal line over a second portion of the substrate, wherein the second signal line is electrically insulated from the first signal line;

forming a first actuation electrode over a third portion of the substrate;

forming a first anchor over a fourth portion of the substrate;

forming first and second electrically conductive beams attached to the first anchor;

forming a first actuation portion attached to the first and second beams and positioned opposite the first actuation electrode;

forming first and second tips attached to the first actuation portion;

forming a first contact dimple attached to the first tip and opposite the first signal line; and

forming a second contact dimple attached to the second tip and opposite the second signal line.

61. The method of claim 60, further comprising:

forming a second actuation electrode over a fifth portion of the substrate;

forming a second anchor over a portion of a sixth portion the substrate;

forming third and fourth electrically conductive beams attached to the second anchor;

forming a second actuation portion attached to the third and fourth beams and positioned opposite the second actuation electrode;

forming third and fourth tips attached to the second actuation portion;

forming a third contact dimple attached to the third tip and opposite the first signal line; and

forming a fourth contact dimple attached to the fourth tip and opposite the second signal line.

62. The method of claim 61, wherein each of the beams is comprised of gold (Au).

63. The method of claim 61, wherein a portion of the first beam attached to the first anchor is wider than a portion of the first beam attached to the first actuation portion and wherein a portion of the second beam attached to the first anchor is wider than a portion of the second beam attached to the first actuation portion.

64. The method of claim 61, wherein a portion of the third beam attached to the second anchor is wider than a portion of the third beam attached to the second actuation portion and wherein a portion of the fourth beam attached to the second anchor is wider than a portion of the fourth beam attached to the second actuation portion.

65. The method of claim 61, further comprising:

providing an electrical connection between the first signal line and the second signal line to permit a signal coupling between first and second signal lines.

66. The method of claim 65, wherein the providing the electrical connection comprises inducing charge in the first and second actuation electrodes to draw first and third contact dimples in contact with the first signal line and to draw second and fourth contact dimples in contact with the second signal line.

67. A method comprising:

forming an actuation region buried in a dielectric layer, wherein the dielectric layer is formed over a substrate;

forming first and second dielectric pads over the dielectric layer;

forming an electrode over the dielectric layer and coupled to the actuation region;

forming a signal line over the dielectric layer;

forming a beam, wherein the beam comprises;

attachments that attach the beam to the first and second dielectric pads,

an actuation portion opposite the electrode, and

a contact portion having a contact dimple formed thereon and opposite the signal line.

68. The method of claim 67, wherein the forming the beam comprises:

providing a structural layer; and

surrounding the structural layer with electrically conductive layers.

69. The method of claim 67, wherein the forming the beam comprises:

forming the beam to decrease in width from the attachment to the actuation portion.

70. The method of claim 67, wherein the actuation portion is wider than the contact portion.

71. The method of claim 67, further comprising:

drawing the dimple into contact with the signal line; and

shunting to ground current through the signal line.

72. The method of claim 71, wherein the drawing comprises inducing a charge in the electrode to draw the actuation portion of the beam towards the electrode.

73. A method comprising:

forming an actuation region buried in a dielectric layer, wherein the dielectric layer is formed over a substrate;

forming first and second dielectric pads over the dielectric layer;

forming an electrode over the dielectric layer and coupled to the actuation region;

forming first and second signal lines over the dielectric layer, wherein the first and second signal line are electrically isolated;

forming a first beam, wherein the first beam comprises;

attachments that attach the first beam to the first and second dielectric pads,

a contact portion having a contact dimple formed thereon and opposite the first signal line, and

an actuation portion opposite of the electrode; and

forming a second beam, wherein the second beam comprises;

attachments that attach the second beam to the first and second dielectric pads, and

a contact portion having a contact dimple formed thereon and opposite the second signal line, wherein the first and second beams share the actuation portion.

74. The method of claim 73, wherein the forming the first beam comprises:

providing a structural layer; and

surrounding the structural layer with electrically conductive layers.

75. The method of claim 73, wherein the forming the second beam comprises:

providing a structural layer; and

surrounding the structural layer with electrically conductive layers.

76. The method of claim 73, further comprising:

inducing a charge in the electrode to draw the actuation portion of the first and second beams towards the electrode and to draw the contact dimple of the first beam into contact with the first signal line and to draw the contact dimple of the second beam into contact with the second signal line.