Self-shadowing MEM structures

• US 6,937,131 B2
• Filed: 11/12/2004
• Issued: 08/30/2005
• Est. Priority Date: 03/15/2002
• Status: Expired due to Fees

• Current Assignee: MEMX, Inc. (Lumentum Holdings Inc.)
• Original Assignee: MEMX, Inc. (Lumentum Holdings Inc.)
• Inventors: Rodgers, Murray Steven, Miller, Samuel Lee
• Primary Examiner(s): Vortman, Anatoly
• Application Number:
  US10/987,679
• Publication Number:
  US 20050088765A1
• Time in Patent Office: 291 Days
• Field of Search: 337/142, 337/144, 337/150, 337/154, 359/883, 359/884, 359/838, 359/224, 438/29, 438/69, 438/132, 438/467, 438/601, 327/525, 335/142, 296/23, 403/5, 385 16- 18
• US Class Current: 337/144
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81B 7/0006 Interconnects
• CPC Class Codes: B81C 1/00833 Methods for preserving structures not provided for in groups B81C1/00785 - B81C1/00825
• 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 6/357 Electrostatic force electrostatic forces controlling reflecting elements in general G02B26/0841

Abstract

Self-shadowed microelectromechanical structures such as self-shadowed bond pads, fuses and compliant members and a method of fabricating self-shadowing microelectromechanical structures that anticipate and accommodate blanket metalization process steps are disclosed. In one embodiment, a self-shadowed bond pad (10) configured for shadowing an exposed end (44A) of a shielded interconnect line (44) connected to the bond pad (10) from undesired metalization during a metalization fabrication process step includes electrically connected overlaying first, second and third bond pad areas (42, 72, 92) patterned from respective first, second and third layers (40, 70, 90) of material deposited on a substrate (20). The exposed end (44A) of the interconnect line (44) abuts an edge of the first bond pad area (42). The third bond pad area (92) includes at least one tab portion (94) extending laterally from an edge of the third bond pad area (92) to shadow an area on the substrate (20) including the exposed end (44A) of the interconnect line (44) abutting the edge of the first bond pad area (42).

Claims

1. A self-shadowed microelectromechanical fuse structure for temporarily holding a moveable microelectromechanical structure in place that is shadowed from undesired metalization during a metalization fabrication process step, said self-shadowed fuse structure comprising:

a substrate;

lower and upper layers of material deposited on said substrate, the moveable microelectromechanical structure being patterned from said lower and upper layers of material providing the moveable microelectromechanical structure with lower and upper layer portions;

at least one filament patterned from said lower layer of material, said filament being connected to said lower layer portion of the moveable microelectromechanical structure to temporarily hold the moveable microelectromechanical structure in place; and

a tab patterned from said upper layer, wherein said tab shadows an area on said substrate including said filament.

2. The self-shadowed microelectromechanical fuse structure of claim 1 wherein said lower layer of material comprises an electrically conductive material and said filament is severable upon application of sufficient electrical current therethrough.

3. The self-shadowed fuse structure of claim 1 wherein said tab extends laterally from an edge of the upper layer portion of the moveable microelectromechanical structure.

4. The self-shadowed fuse structure of claim 1 wherein said tab extends laterally from an upper layer portion of a bond pad structure that is fixed to said substrate.