High density composite focal plane array

• US 9,070,566 B2
• Filed: 02/13/2013
• Issued: 06/30/2015
• Est. Priority Date: 11/12/2008
• Status: Active Grant

• Current Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Original Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Inventors: Silva, Raymond J., Bowler, Dennis P., Robillard, Gene A.
• Primary Examiner(s): Martinez, Joseph P
• Assistant Examiner(s): THOMAS, BRANDI N
• Application Number:
  US13/766,443
• Publication Number:
  US 20130182180A1
• Time in Patent Office: 867 Days
• Field of Search: 359294-324, 359/274, 359/275, 257/700, 257/703, 257/706, 349294-324, 349/274, 349/275, 349/340, 349373-375
• US Class Current: 1/1
• CPC Class Codes: H01L 25/065 the devices being of a type provided for in group H01L27/00
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils

Abstract

A composite focal plane assembly with an expandable architecture has a multi-layer, double-sided aluminum nitride (AlN) substrate and vertical architecture to achieve the dual function of focal plane and electronics backplane. Imaging dice and other electrical components are mounted and wire bonded to one surface and then direct backplane connectivity is provided on the opposing surface through a matrix of electrical contacts. In one embodiment, a flexible connector is sandwiched between the AlN focal plane and a FR-4 backplane is used to compensate for differences in coefficient of thermal expansion (CTE) between the AlN and commercially available high density circuit card connectors that are commonly manufactured from materials with CTE properties more closely approximating FR-4. In an alternate embodiment, the FR-4 and flexible connectors are eliminated by using high density circuit card connectors that are fabricated out of materials more closely matching the CTE of AlN.

Claims

1. A focal plane and back plane assembly comprising:

an aluminum nitride printed wiring board;

a plurality of imaging dies mounted on the aluminum nitride printed wiring board;

a plurality of signal lines routed through the aluminum nitride printed wiring board;

at least one connector connected to the back of the printed wiring board providing an electrical connection to the signal lines of the aluminum nitride printed wiring board; and

a back plane motherboard having electrical connections to the connector.

2. The apparatus of claim 1 wherein the plurality of imaging dies are mounted on an image receiving plane of the aluminum nitrite printed wiring board and the connector is mounted on the back opposite to the image receiving plane.

3. The apparatus of claim 1 wherein the motherboard is a FR-4 material.

4. A high-density focal plane assembly having an integral back plane comprising:

an aluminum nitride printed -wiring board having a plurality of imaging dies on a first surface and signal lines (vias) routed through the aluminum nitride printed wiring board to a second surface of the aluminum nitride printed wiring board;

a back plane motherboard having electrical contacts;

a connector sandwiched between the aluminum nitride printed wiring board and the motherboard wherein the connector connects the signal lines of the aluminum nitride printed wiring board to the motherboard electrical contacts.