US3977910A
Expired / Lapsed
US
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Deep finger diodes
Assignee: General Electric Co
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Filing: 1975-01-30
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Granted: 1976-08-31
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Expires: 1995-01-30
Abstract
Abstract Deep finger diodes in a body of semiconductor material are fabricated by a thermal gradient zone melting process. A liquid wire or droplet is migrated into the body through one surface to a depth less than the thickness of the body. The migration of the liquid wire or droplet is reversed to remove the wire or droplet from the body leaving a recrystallized material of the body having solid solubility of a material therein.
Inventors
- 👤 Thomas R. Anthony
- 👤 Harvey E. Cline
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:33
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/124; H10D62/125; H10D62/40; H10D99/00; H10P; H10P10/00; H10P10/12; H10P95/00; H10P95/50; H10W; H10W10/00; H10W10/01; H10W10/031; H10W10/30
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
348 words
A process for making a semiconductor device comprising the process steps of: a. selecting a body of semiconductor material having a predetermined leverl of resistivity, a predetermined type conductivity and two major opposed surfaces which are, respectively, the top and bottom surfaces thereof, at least one of the major surfaces having a preferred planar crystal structure orientation, and a vertical axis of the body being substantially aligned parallel with a first axis of the crystal structure which is substantially perpendicular to at least the major surface having the preferred planar orientation; b. selectively etching a selective portion of the at least one major surface having a preferred crystal planar orientation to form depressions therein having a preferred geometric configuration; c. vapor depositing a layer of metal of a preferred thickness in each depression; d. forming a melt of the metal and a portion of the semiconductor material of the body in contact therewith on the major surface of the body; e. establishing a first thermal gradient substantially parallel with the vertical axis and the first crystal axis of the body; f. migrating each melt into the body a predetermined distance in the direction of the higher temperature of the thermal gradient from the one major surface less than the distance between the two major opposed surfaces to form a first region of recrystallized semiconductor material of the body having solid solubility of the selective metal therein; g. establishing a second thermal gradient substantially parallel with the vertical axis and the first crystal axis of the body, and h. migrating each melt from that point within the body wherein the melt had migrated to that major opposed surface from which the melt had initially been migrated therefrom to form a second region of recrystallized material of the the first region and having solid solubility of the deposited metal therein of a predetermined concentration sufficient to impart a second and opposite type conductivity thereto than that of the body and also forming a P-N junction at the contiguous surfaces of the material comprising respectively the second region and the body.
Claim 2
Dependent Claim
348 words
A process for making a semiconductor device comprising the process steps of: a. selecting a body of semiconductor material having a predetermined leverl of resistivity, a predetermined type conductivity and two major opposed surfaces which are, respectively, the top and bottom surfaces thereof, at least one of the major surfaces having a preferred planar crystal structure orientation, and a vertical axis of the body being substantially aligned parallel with a first axis of the crystal structure which is substantially perpendicular to at least the major surface having the preferred planar orientation; b. selectively etching a selective portion of the at least one major surface having a preferred crystal planar orientation to form depressions therein having a preferred geometric configuration; c. vapor depositing a layer of metal of a preferred thickness in each depression; d. forming a melt of the metal and a portion of the semiconductor material of the body in contact therewith on the major surface of the body; e. establishing a first thermal gradient substantially parallel with the vertical axis and the first crystal axis of the body; f. migrating each melt into the body a predetermined distance in the direction of the higher temperature of the thermal gradient from the one major surface less than the distance between the two major opposed surfaces to form a first region of recrystallized semiconductor material of the body having solid solubility of the selective metal therein; g. establishing a second thermal gradient substantially parallel with the vertical axis and the first crystal axis of the body, and h. migrating each melt from that point within the body wherein the melt had migrated to that major opposed surface from which the melt had initially been migrated therefrom to form a second region of recrystallized material of the the first region and having solid solubility of the deposited metal therein of a predetermined concentration sufficient to impart a second and opposite type conductivity thereto than that of the body and also forming a P-N junction at the contiguous surfaces of the material comprising respectively the second region and the body.
Claim 3
Dependent Claim
51 words
The process for making the semiconductor device of claim 1 including the additional process step of: heat treating the body of semiconductor material to stress relieve at least that portion of the P-N junction formed therein in the vicinity of that point where the second migration of the melt was initiated.
Claim 4
Dependent Claim
21 words
The process of claim 1 wherein the method employed to deposit the method produces a mass of substantially oxygen free metal.
Claim 5
Dependent Claim
32 words
The process of claim 1 wherein the at least one of the major surfaces has a preferred planar crystal orientation of (111), and the first crystal axis of the body is <111>.
Claim 6
Dependent Claim
19 words
The process of claim 4 wherein the material of the body is silicon, silicon carbide, germanium and gallium arsenide.
Claim 7
Dependent Claim
29 words
The process of claim 4 wherein the material of the body is silicon of N-type conductivity, and the metal which has solid solubility in the recrystallized silicon is aluminum.
Claim 8
Dependent Claim
38 words
The process of claim 4 wherein each depression has a preferred configuration of a "wire" which has a preferred second crystal axis direction which is at least one selected from the group consisting of <011>, <101> and <100>.
Claim 9
Dependent Claim
19 words
The process of claim 7 wherein the material of the body is silicon, silicon carbide, germanium and gallium arsenide.
Claim 10
Dependent Claim
27 words
The process of claim 8 wherein the material of the body is silicon of N-type conductivity, and the solid solubility metal in the recrystallized silicon is aluminum.
Claim 11
Dependent Claim
37 words
The process of claim 4 wherein each depression has a preferred configuration of a "wire" and a preferred second crystal axis direction which is at least one selected from the group consisting of <112>, <211> and <121<.
Claim 12
Dependent Claim
19 words
The process of claim 10 wherein the material of the body is silicon, silicon carbide, germanium and gallium arsenide.
Claim 13
Dependent Claim
27 words
The process of claim 11 wherein the material of the body is silicon of N-type conductivity, and the solid solubility metal in the recrystallized silicon is aluminum.
Claim 14
Dependent Claim
34 words
The process of claim 4 wherein at least one depression has a configuration of a wire and a width suitable to form a stable wire of less than 500 microns in width for migration.
Claim 15
Dependent Claim
33 words
The process of claim 4 wherein each depression has a second preferred crystal axis direction which is at least one selected from the group consisting of <011>, <101>, <110>, <112>, <211> and <121>.
Claim 16
Dependent Claim
32 words
The process of claim 1 wherein the at least one of the major surfaces has a preferred planar crystal orientation of (100), and the first crystal axis of the body is <100>.
Claim 17
Dependent Claim
19 words
The process of claim 15 wherein the material of the body is silicon, silicon carbide, germanium and gallium arsenide.
Claim 18
Dependent Claim
27 words
The process of claim 16 wherein the material of the body is silicon of N-type conductivity, and the solid solubility metal in the recrystallized silicon is aluminum.
Claim 19
Dependent Claim
40 words
The process of claim 15 wherein each depression of metal has a preferred linear configuration of a wire oriented in a preferred second crystal axis direction which is at least one selected from the group consisting of <011> and <011>.
Claim 20
Dependent Claim
19 words
The process of claim 18 wherein the material of the body is silicon, silicon carbide, germanium and gallium arsenide.
Claim 21
Dependent Claim
27 words
The process of claim 19 wherein the material of the body is silicon of N-type conductivity, and the solid solubility metal in the recrystallized silicon is aluminum.
Claim 22
Dependent Claim
31 words
The process of claim 18 wherein each depression which has a wire-like configuration has a width suitable to form a stable wire of less than 100 microns in width for migration.
Claim 23
Dependent Claim
52 words
The process of claim 1 wherein the at least one of the opposed major surface has a preferred planar crystal orientation of (110); each depression has a preferred linear configuration of a wire and a second preferred crystal axis direction of <110>, and the first crystal axis of the body is <110>.
Claim 24
Dependent Claim
19 words
The process of claim 22 wherein the material of the body is silicon, silicon carbide, germanium and gallium arsenide.
Claim 25
Dependent Claim
27 words
The process of claim 23 wherein the material of the body is silicon of N-type conductivity, and the solid solubility metal in the recrystallized silicon is aluminum.
Claim 26
Dependent Claim
31 words
The process of claim 22 wherein each depression which has a wire-like configuration has a width suitable to form a stable wire of less than 150 microns in width for migration.
References Cited (Backward Citations)
US2813048A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-31 | 1980-03-01 | 1980-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-31 | 1984-03-01 | 1984-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-31 | 1988-03-01 | 1988-08-31 | $7700.00 | Window Closed / Lapsed |