US4290844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Focal plane photo-detector mosaic array fabrication
Assignee: Carson Alexiou Corp
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Filing: 1979-02-26
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Granted: 1981-09-22
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Expires: 1999-02-26
Abstract
Abstract A focal plane detector mosaic array is formed by securing wafers of the detector material to a focal plane having individual conductor leads embedded therein, ion milling to delineate separate detector islands in individual electrical contact with the conductor leads, and using ion implantation to form p-n junctions in the detector islands.
Inventors
- 👤 Ralph A. Rotolante
- 👤 Toivo Koehler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:28
CPC Classifications
H; H10; H10F; H10F39/00; H10F39/10; H10F39/12; H10F39/18; H10F39/184
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
142 words
A method for providing a mosaic of individual photo-detector elements on the focal plane of a support structure having a multiplicity of individual electrical conductors buried within it and terminating in separate electrical contact points at its focal plane, which method comprises the following steps: securing a thin wafer of detector material to the focal plane face of said supporting structure in such a way that the wafer material is in electrical contact with said contact points; and thereafter delineating individual detector islands by removing material from the wafer to form channels located between the electrical contact points and dividing the wafer into a multiplicity of individual detector islands adapted to provide detector elements each of which is isolated from all the others and each of which is directly over and in electrical contact with a separate one of said contact points.
Claim 2
Independent Claim
142 words
A method for providing a mosaic of individual photo-detector elements on the focal plane of a support structure having a multiplicity of individual electrical conductors buried within it and terminating in separate electrical contact points at its focal plane, which method comprises the following steps: securing a thin wafer of detector material to the focal plane face of said supporting structure in such a way that the wafer material is in electrical contact with said contact points; and thereafter delineating individual detector islands by removing material from the wafer to form channels located between the electrical contact points and dividing the wafer into a multiplicity of individual detector islands adapted to provide detector elements each of which is isolated from all the others and each of which is directly over and in electrical contact with a separate one of said contact points.
Claim 3
Dependent Claim
45 words
The method of claim 1 to which the following step is added: after the individual detector islands have been formed and isolated from one another, creating in each of said detector islands a diode junction near its top surface to provide an isolated detector element.
Claim 4
Dependent Claim
21 words
The method of claim 2 wherein the diode junctions are created in the individual detector islands by an ion implantation process.
Claim 5
Dependent Claim
11 words
The method of claim 3 wherein the implanted ions are boron.
Claim 6
Dependent Claim
30 words
The method of claim 1 or claim 2 wherein the wafer of detector material is secured to the focal plane face of the supporting structure by means of an electrically-conducting.
Claim 7
Dependent Claim
38 words
The method of claim 5 wherein: the electrically-conducting epoxy is applied as a layer on the focal planes; and removal of material to form channels, thereby providing isolated detector islands, first removes detector material and thereafter removes epoxy.
Claim 8
Dependent Claim
44 words
The method of claim 6 wherein the detector and epoxy material is removed by: applying a titanium oxide mask to protect the areas of the individual detector islands; and thereafter using an ion milling process to remove detector and epoxy material from the channels.
Claim 9
Dependent Claim
27 words
The method of claim 1 or claim 2 wherein the individual detector islands, after being delineated, are covered with a thin passivation layer of infrared transparent material.
Claim 10
Dependent Claim
25 words
The method of claim 1 or claim 2 wherein, after the individual detector islands have been delineated, the channels therebetween are filled with dielectric material.
Claim 11
Dependent Claim
43 words
The method of claim 9 wherein a further structural step is forming on top of the focal plane an electrically-conducting grid which constitutes a common electrode for the multiplicity of detector islands and which is supported on the dielectric material in the channels.
Claim 12
Dependent Claim
65 words
The method of claim 10 which is preceded by the step of: forming a focal plane support structure by stacking a plurality of thin layers extending in planes perpendicular to the focal plane and each having on one surface thereof a multiplicity of separate electrical conductors extending to its focal plane end to provide a multiplicity of individual electrical contact points at the focal plane.
Claim 13
Independent Claim
36 words
The method of claims 1, 2 or 5 wherein a further structural step is forming on top of the focal plane an electrically conducting grid which constitutes a common electrode for the multiplicity of detector islands.
Claim 14
Dependent Claim
28 words
The method of claim 1 or claim 2 wherein the wafer of detector material is substantially reduced in thickness after it has been secured to the supporting structure.
Claim 15
Dependent Claim
68 words
The method of claim 1 or claim 2 which is preceded by the step of: forming a focal plane support structure by stacking a plurality of thin layers extending in planes perpendicular to the focal plane and each having on one surface thereof a multiplicity of separate electrical conductors extending to its focal plane end to provide a multiplicity of individual electrical contact points at the focal plane.
Claim 16
Dependent Claim
28 words
The method of claim 14 wherein each detector island provides a separate detector element having a spacing from each of the adjacent detector elements of about 0.005 inch.
Claim 17
Dependent Claim
31 words
The method of claim 1 or claim 2 wherein each detector island provides a separate detector element having a spacing from each of the adjacent detector elements of about 0.005 inch.
Claim 18
Dependent Claim
57 words
The method of claim 1 or claim 2 wherein the material is removed from the wafer to delineate individual detector islands by: applying a mask to protect the areas of the individual detector islands; and thereafter using an ion milling process to remove detector material from the channels, thereby isolating the individual detector islands from one another.
Claim 19
Dependent Claim
45 words
The method of claim 1 wherein the wafer of detector material, before its surface is secured to the supporting structure, is provided with a highly doped region and a thin layer of highly electrically-conductive material on such surface in order to provide an ohmic contact.
Claim 20
Independent Claim
86 words
A method for providing a focal plane mosaic of photo-detector elements on a supporting structure comprising: applying a layer of electrically-conducting epoxy to the focal plane; placing a wafer of mercury cadmium telluride on the epoxy; applying a titanium oxide mask on the exposed side of the wafer for the purpose of protecting individual islands of mercury cadmium telluride material; and using an ion milling process to remove both detector material and epoxy material from the unprotected spaces between the islands of mercury cadmium telluride material.
Claim 21
Independent Claim
86 words
A method for providing a focal plane mosaic of photo-detector elements on a supporting structure comprising: applying a layer of electrically-conducting epoxy to the focal plane; placing a wafer of mercury cadmium telluride on the epoxy; applying a titanium oxide mask on the exposed side of the wafer for the purpose of protecting individual islands of mercury cadmium telluride material; and using an ion milling process to remove both detector material and epoxy material from the unprotected spaces between the islands of mercury cadmium telluride material.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-09-21 | 1985-03-23 | 1985-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-21 | 1989-03-23 | 1989-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-21 | 1993-03-23 | 1993-09-22 | $7700.00 | Window Closed / Lapsed |