US4864378A
Expired / Lapsed
US
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Schottky barrier infrared detector
Assignee: Massachusetts Institute of Technology
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Filing: 1987-10-21
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Granted: 1989-09-05
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Expires: 2007-10-21
Abstract
Abstract A method and resultant device is described for fabricating iridium silicide Schottky IR detectors in which a thin intermediate film of platinum is formed between the conventional iridium outer layer over a p-type silicon substrate with or without an n-type guard ring. After thermal treatment, an iridium platinum silicide region is formed in the silicon substrate. The unreated iridium/platinum outside the device region is removed using a dry-etching process.
Inventors
- 👤 Bor-Yeu Tsaur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:36
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/012; H10D64/0121; H10D64/60; H10D64/64; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/227; H10F39/00; H10F39/10; H10F39/107
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
104 words
A method of forming a detector comprising the steps of: (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, Ni, Pd on the structure formed in step (c); (e) forming a second layer of the metal Ir on the first layer; (f) heat treating said structure to form silicides of said metals in said substrate, at said openings; and (g) removing portions of said metal layers over said surrounding insulator.
Claim 2
Independent Claim
104 words
A method of forming a detector comprising the steps of: (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, Ni, Pd on the structure formed in step (c); (e) forming a second layer of the metal Ir on the first layer; (f) heat treating said structure to form silicides of said metals in said substrate, at said openings; and (g) removing portions of said metal layers over said surrounding insulator.
Claim 3
Independent Claim
108 words
A method of forming a detector comprising the steps of: (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, Ni, Pd on the structure formed in step (c); (e) forming a second layer of the metal Ir on the first layer; (f) removing portions of said first and second layers over the insulator surrounding the openings; and (g) heat treating said structure to form silicides of said metals in said substrate, at said openings.
Claim 4
Independent Claim
108 words
A method of forming a detector comprising the steps of: (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, Ni, Pd on the structure formed in step (c); (e) forming a second layer of the metal Ir on the first layer; (f) removing portions of said first and second layers over the insulator surrounding the openings; and (g) heat treating said structure to form silicides of said metals in said substrate, at said openings.
Claim 5
Dependent Claim
22 words
The method of claim 1 wherein n-type guard ring regions are formed in said Si substrate around the edges of said opening.
Claim 6
Dependent Claim
22 words
The method of claim 2 wherein n-type guard ring regions are formed in said Si substrate around the edge of said opening.
Claim 7
Independent Claim
134 words
A method of forming an infrared-light sensitive detector on a Si substrate comprising the steps of: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of p-type doped regions separated by n-type doped guard ring regions; (b) forming an insulating layer over said structure; (c) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c); (e) removing portions of said successive layers over said guard ring regions; (f) heat treating the structure formed in step to produce silicide regions in said substrate, at said openings.
Claim 8
Independent Claim
134 words
A method of forming an infrared-light sensitive detector on a Si substrate comprising the steps of: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of p-type doped regions separated by n-type doped guard ring regions; (b) forming an insulating layer over said structure; (c) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c); (e) removing portions of said successive layers over said guard ring regions; (f) heat treating the structure formed in step to produce silicide regions in said substrate, at said openings.
Claim 9
Independent Claim
137 words
A method of forming an infrared-light sensitive detector on a Si substrate comprising the steps of: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of islands of p-type doped regrons separated by n-type doped guard ring regions; (b) forming an insulating layer over said structure; (c) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c); (e) heat treating the structure formed in step (d) to produce silicide regions in said substrate at said openings; (f) removing portions of said successive layers over said guard ring regions.
Claim 10
Independent Claim
137 words
A method of forming an infrared-light sensitive detector on a Si substrate comprising the steps of: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of islands of p-type doped regrons separated by n-type doped guard ring regions; (b) forming an insulating layer over said structure; (c) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c); (e) heat treating the structure formed in step (d) to produce silicide regions in said substrate at said openings; (f) removing portions of said successive layers over said guard ring regions.
Claim 11
Dependent Claim
34 words
An infrared detector comprised of a region formed of a silicide of Ir and a silicide of Pt, Ni, or Pd, formed in a p-type doped Si substrate with an insulator encircling said region.
Claim 12
Dependent Claim
34 words
An infrared detector comprised of a region formed of a silicide of Ir and a silicide of Pt, Ni, or Pd, formed in a p-type doped Si substrate with an insulator encircling said region.
Claim 13
Dependent Claim
13 words
The detector of claim 11 including an n-type guard region beneath said insulator.
Claim 14
Dependent Claim
21 words
The method of claim 1 wherein the first layer of metal is formed of about 5 Å thick film of Pt.
Claim 15
Dependent Claim
21 words
The method of claim 2 wherein the first layer of metal is formed of about 5 Å thick film of Pt.
Claim 16
Dependent Claim
17 words
The method of claim 9 wherein the heat treatment occurs at a temperature between 300° C.-600° C.
Claim 17
Dependent Claim
17 words
The method of claim 14 wherein the heat treatment occurs at a temperature between. 300° C.-600° C.
Claim 18
Dependent Claim
15 words
The method of claim 1 wherein the metal layer portions are removed by dry etching.
Claim 19
Dependent Claim
15 words
The method of claim 2 wherein the metal layer portions are removed by dry etching.
Claim 20
Dependent Claim
41 words
An infrared-light sensitive detector formed of a metallic electrode formed in a p-type substrate and encircled on one side by an insulator, said electrode being comprised of a bi-layer of Pt silicide and Ir silicide, or a mixture of said silicides.
Claim 21
Dependent Claim
41 words
An infrared-light sensitive detector formed of a metallic electrode formed in a p-type substrate and encircled on one side by an insulator, said electrode being comprised of a bi-layer of Pt silicide and Ir silicide, or a mixture of said silicides.
Claim 22
Dependent Claim
14 words
The detector of claim 15 including an n-type silicon guard ring about said electrode.
Claim 23
Dependent Claim
114 words
An infrared-light sensitive detector formed by the following process: (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, Ni, Pd on the structure formed in step (c) to dissolve any interfacial contaminants or natuve oxides on said substrate; (e) forming a second layer of the metal Ir on the first layer; (F) heat treating said structure to form silicides of said metals in said substrate, at said openings; and (g) removing portions of said metal layers over said surrounding insulator.
Claim 24
Dependent Claim
114 words
An infrared-light sensitive detector formed by the following process: (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, Ni, Pd on the structure formed in step (c) to dissolve any interfacial contaminants or natuve oxides on said substrate; (e) forming a second layer of the metal Ir on the first layer; (F) heat treating said structure to form silicides of said metals in said substrate, at said openings; and (g) removing portions of said metal layers over said surrounding insulator.
Claim 25
Dependent Claim
107 words
An infrared-light sensitive detector formed by the following process. (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, NI, Pd on the structure formed in step (c); (e) forming a second layer of the metal Ir on the first layer; (f) removing portions of said first and second layers over the insulator surrounding the openings; and (g) heat treating said structure to form silicides of said metals in said substrate, at said openings.
Claim 26
Dependent Claim
107 words
An infrared-light sensitive detector formed by the following process. (a) forming an Si substrate; (b) forming an insulating layer over said substrate; (c) forming openings in said layer to said substrate, said openings being laterally surrounded by said insulator; (d) forming a first layer of a metal from the group comprising Pt, NI, Pd on the structure formed in step (c); (e) forming a second layer of the metal Ir on the first layer; (f) removing portions of said first and second layers over the insulator surrounding the openings; and (g) heat treating said structure to form silicides of said metals in said substrate, at said openings.
Claim 27
Dependent Claim
128 words
An infrared-light sensitive detector formed by the following process: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of p-type doped regions separated by n-type doped guard ring regions; (b) forming an insulating layers over said structure; (C) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c): (e) removing portions of said successive layers over said guard ring regions; (f) heat treating the structure formed in step (e) to produce silicide regions in said substrate, at said openings.
Claim 28
Dependent Claim
128 words
An infrared-light sensitive detector formed by the following process: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of p-type doped regions separated by n-type doped guard ring regions; (b) forming an insulating layers over said structure; (C) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c): (e) removing portions of said successive layers over said guard ring regions; (f) heat treating the structure formed in step (e) to produce silicide regions in said substrate, at said openings.
Claim 29
Dependent Claim
130 words
An infrared-light sensitive detector formed by the following process: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of islands of p-type doped regions separated by n-type doped guard ring regions; (b) forming an insulating layer over said structure; (c) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c) ; heat treating the structure formed in step (d) to produce silicide regions in said substrate at said openings; (f) removing portions of said successive layers over said guard ring regions.
Claim 30
Dependent Claim
130 words
An infrared-light sensitive detector formed by the following process: (a) forming a bounded region of an n-type dopant in a p-type doped substrate thereby forming a structure comprised of islands of p-type doped regions separated by n-type doped guard ring regions; (b) forming an insulating layer over said structure; (c) forming openings in said insulating layer to a surface of said substrate, which openings extend to at least a substantial portion of the guard ring regions; (d) forming successive layers of a material from the group comprising Pt, Ni, Pd then Ir over the structure formed in step (c) ; heat treating the structure formed in step (d) to produce silicide regions in said substrate at said openings; (f) removing portions of said successive layers over said guard ring regions.
Claim 31
Dependent Claim
17 words
The method of claim 1 wherein the first layer is in the order of 5 Å thick.
Claim 32
Dependent Claim
19 words
The method of claim 1 wherein the first and second layers form a low-barrier height contact to said substrate.
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) | 1992-09-04 | 1993-03-06 | 1993-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-04 | 1997-03-06 | 1997-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-04 | 2001-03-06 | 2001-09-05 | $7700.00 | Window Closed / Lapsed |