Glue-free backside illuminated photodiode apparatus and fabrication process
AssigneeLockheed Martin Corporation
InventorsWilliam J. White, Miriam F. Young
Life of this patent
Estimating the term…
Abstract
Apparatus and method for fabricating a backside illuminated photodiode array is described which does not use epoxy, and therefore has better transmission characteristics. The method uses indium or other coldweldable metal to fasten the detectors to the transmissive substrate. Because the indium is opaque in the waveband of detector sensitivity, it also forms an optical mask for each detector element.
Claims11
A method for fabricating a backside contacted photodiode detector assembly from a first substrate, said assembly for operation at a desired waveband, said first substrate having a first surface and a second surface, said method comprising the steps of:
- A. depositing a pattern of coldweldable metal on said first surface of said first substrate, said pattern having at least one hole, thereby exposing said first surface of said first substrate at said at least one hole, wherein said coldweldable metal is substantially opaque at said desired waveband;
- B. coldwelding a second substrate to said pattern of coldweldable metal, wherein said second substrate is substantially transmissive at said desired waveband;
- and
- C. forming detector elements substantially on said second surface of said first substrate at positions substantially opposite said at least one hole in said pattern of coldweldable metal.
A backside contacted photodiode detector article for operation at a desired waveband, said article comprising:
- A. a first substrate, said first substrate having a first surface and a second surface;
- B. a pattern of metal coldwelded on said first surface of said first substrate, said pattern having at least one hole, thereby exposing said first surface of said first substrate at said at least one hole, wherein said coldwelded metal is substantially opaque at said desired waveband;
- C. a second substrate coldwelded to said pattern of coldwelded metal, wherein said second substrate is substantially transmissive at said desired waveband;
- and
- D. detector elements formed substantially on said second surface of said first substrate at positions substantially opposite said at least one hole in said pattern of coldwelded metal.
Dependencies are inferred from the claim text.