Method of making a miniaturized electronic imaging chip from a standard imaging chip

• US 5,633,203 A
• Filed: 05/05/1995
• Issued: 05/27/1997
• 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): Fourson, George
• Assistant Examiner(s): Kirkpatrick, Scott
• Application Number:
  US08/435,997
• Time in Patent Office: 753 Days
• Field of Search: 437/183, 437/923, 437/209, 437/2, 358/98
• US Class Current: 438/66
• 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 comprises the steps of shaving a silicon layer, 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 shaved silicon layer. 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 method of forming a miniaturized electronic imaging chip from a standard imaging chip, the standard imaging chip having a substrate with a first peripheral edge defining a first area, and having stratified layers which include at least one interconnect layer, through which an image is normally projected, a pixel layer for receiving the image, a silicon layer having a second peripheral edge defining a second area which is smaller than the first area, the substrate being connected to first ends of connector pins, and having electrical leads connected between the interconnect layer and electrical contacts on the substrate to which the first ends of the connector pins are attached, the connector pins having second ends attached to circuitry which incorporates the standard imaging chip, said method comprising the steps of:

removing the electrical leads;

removing the at least one interconnect layer, pixel layer, and silicon layer from the substrate;

shaving the silicon layer to a thickness which allows passage of a light image therethrough;

bump bonding new lead to the interconnect layer within the second area of the shaved silicon layer; and

reversing the chip so that a light image is projectable through the shaved silicon layer, the new leads being directly attachable to the circuitry.

2. A method, as claimed in claim 1, including the further step of:

projecting an image onto the pixel layer through the shaved silicon layer.