Miniaturized electronic imaging chip

• US 5,495,114 A
• Filed: 11/22/1993
• Issued: 02/27/1996
• Est. Priority Date: 09/30/1992
• Status: Expired due to Fees

• Current Assignee: Edwin L. Adair
• Original Assignee: Edwin L. Adair
• Inventors: Adair, Edwin L.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Wallace, Valencia Martin
• Application Number:
  US08/155,996
• Time in Patent Office: 827 Days
• Field of Search: 257/53, 257/59, 257/98, 257/447, 257/448, 257/464, 257/439, 257/228, 358/2, 358/98, 358/213.11, 348/45, 348/46, 348/47, 348/65, 348/67, 348/68
• US Class Current: 257/59
• CPC Class Codes: A61B 1/00193 adapted for stereoscopic vision
• CPC Class Codes: A61B 1/05 characterised by the image sensor, e.g. camera, being in the distal end portion
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 27/14868 CCD or CID colour imagers
• CPC Class Codes: Y10S 438/977 Thinning or removal of substrate

Abstract

A miniaturized electronic imaging chip has stratified layers wherein a base silicon layer has a peripheral edge defining an area and a thickness which allows passage therethrough of most UV, visible and IR light. A pixel layer is formed on the back side of this first silicon layer. At least one interconnect layer is bonded to the pixel layer. Electric leads are bump bonded to the bonding pads on the outermost interconnect layer and extend away from it within the area for attachment to means for sensing electrical signals generated by an image projected onto the pixel layer through the silicon layer. Preferably, the leads are perpendicular to the chip. A unique method of manufacturing the miniaturized electronic imaging chip from a standard CCD, having a peripheral edge defining a first area, comprises the steps of shaving a silicon substrate, having a peripheral edge defining a second area which is smaller than the first area, on the back side of the standard CCD to a thickness which allows passage of a light image therethrough. The CCD then is reversed so that the image is projected through the thinner back side of the silicon substrate. Leads are bumped bonded to the former front surface of the CCD within the smaller second area for supplying electrical signals to and from the CCD.

Claims

1. A miniaturized electronic imaging chip comprising:

a generally rectangular silicon base layer having a thickness which allows a light image to pass therethrough, said silicon layer having a first side, through which the image is projected, and a second side;

a pixel layer having a first and second side, said first side of said pixel layer being attached to said second side of said silicon layer, said pixel layer further having a peripheral edge;

at least one interconnect layer bonded to said second side of said pixel layer; and

electrical leads bonded to and extending substantially perpendicular from said interconnect layer and within an area defined by said peripheral edge of said pixel layer for attachment to means for transmitting electrical signals to and from said pixel layer.

2. Apparatus, as claimed in claim 1, wherein:

said silicon layer as a thickness between 3 and 200 microns.

3. Apparatus, as claimed in claim 1, wherein:

said silicon layer has a thickness between 6 and 10 microns.

4. Apparatus, as claimed in claim 1, wherein:

said electrical leads are indium bump bonded leads.

5. Apparatus, as claimed in claim 1, wherein:

said silicon layer has light transmitting qualities which allow passage of UV, visible and IR light therethrough.