Patent US3880676A successfully refreshed from Google Patents.
US3880676A
Expired / Lapsed
US
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Method of making a semiconductor device
Assignee: RCA Corp
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Filing: 1973-10-29
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Granted: 1975-04-29
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Expires: 1993-10-29
Abstract
Abstract In a method of making a transistor by ion implantation, wherein an emitter region is ion implanted through a window in a layer of silicon dioxide, a capping layer of silicon nitride is deposited over the emitter region before annealing the transistor, whereby out diffusion and evaporation of the emitter dopant atoms are prevented.
Inventors
- 👤 Edward Curtis Douglas
- 👤 Chung Pao Wu
- 👤 Charles William Mueller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:49
CPC Classifications
H; H10; H10P; H10P95/00; Y; Y10; Y10S; Y10S148/00; Y10S148/003; Y10S148/015; Y10S148/043; Y10S148/113; Y10S148/114; Y10S148/145
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
99 words
IN A METHOD OF MAKING A SEMICONDUCTOR DEVICE WHEREIN DOPANT ATOMS ARE ION IMPLANTED INTO A SEMICONDUCTOR MATERIAL THROUGH A PORTION OF A SURFACE THEREOF, DEFINED BY ONE MATERIAL THE IMPROVEMENT COMPRISING THE STEPS OF: DEPOSITING A LAYER OF A CAPPING MATERIAL, IMPENETRABLE TO SAID DOPANT ATOMS BY THERMAL DIFFUSION, ON SAID PORTION OF SAID SURFACE AFTER SAID DOPANT ATOMS ARE ION IMPLANTED, SAID CAPPING MATERIAL BEING ETCHABLE BY AN ETCHANT TO WHICH SAID ONE MATERIAL IS RESISTANT, AND ANNEALING SAID DEVICE, WHEREBY OUT DIFFUSION AND EVAPORATION OF SAID DOPANT ATOMS THROUGH SAID PORTION OF SAID SURFACE ARE PREVENTED.
Claim 2
Dependent Claim
99 words
IN A METHOD OF MAKING A SEMICONDUCTOR DEVICE WHEREIN DOPANT ATOMS ARE ION IMPLANTED INTO A SEMICONDUCTOR MATERIAL THROUGH A PORTION OF A SURFACE THEREOF, DEFINED BY ONE MATERIAL THE IMPROVEMENT COMPRISING THE STEPS OF: DEPOSITING A LAYER OF A CAPPING MATERIAL, IMPENETRABLE TO SAID DOPANT ATOMS BY THERMAL DIFFUSION, ON SAID PORTION OF SAID SURFACE AFTER SAID DOPANT ATOMS ARE ION IMPLANTED, SAID CAPPING MATERIAL BEING ETCHABLE BY AN ETCHANT TO WHICH SAID ONE MATERIAL IS RESISTANT, AND ANNEALING SAID DEVICE, WHEREBY OUT DIFFUSION AND EVAPORATION OF SAID DOPANT ATOMS THROUGH SAID PORTION OF SAID SURFACE ARE PREVENTED.
Claim 3
Dependent Claim
65 words
In a method as described in claim 1, wherein: the step of annealing comprises heating said device to a temperature of between about 700*C and 1,000*C for between about 15 minutes and 1 hour, and said portion of a surface of semiconductor material is defined by a window in said one material, and said capping material is of a different material from said one material.
Claim 4
Dependent Claim
51 words
In a method as described in claim 1, wherein: said portion of a surface of said semiconductor material is defined by an opening in a layer of silicon dioxide, the step of depositing a layer of capping material comprises depositing a layer of silicon nitride on said portion of said surface.
Claim 5
Dependent Claim
51 words
In a method as described in claim 1, wherein: said portion of a surface of said semiconductor material is defined by an opening in a layer of silicon nitride, the step of depositing a layer of capping material comprises depositing a layer of silicon dioxide on said portion of said surface.
Claim 6
Dependent Claim
97 words
In a method as described in claim 1, wherein: said portion of a surface of said semiconductor material is defined by an opening in a layer of insulating material, the step of annealing comprises heating said devices to a temperature of between about 700*C and 1,000*C for between about 15 minutes and 1 hour, and the step of depositing a layer of capping material comprises depositing a layer of a metal having a melting point higher than the temperature used in the step of annealing, said metal being incapable of diffusing into said semiconductor material at 1,000*C.
Claim 7
Dependent Claim
38 words
In a method as described in claim 5, wherein: said metal having a melting point higher than the temperature used in the step of annealing is one chosen from the group consisting of tungsten, molybdenum, platinum, and palladium.
Claim 8
Dependent Claim
87 words
In a method as described in claim 1, wherein: said device is a transistor, said portion of said surface comprises an emitter region of said transistor defined by a window in a layer of silicon dioxide, the step of depositing a layer of a capping material comprises depositing a layer of silicon nitride on said portion of said surface, and the step of annealing said device comprises heating said transistor to a temperature of between about 700*C and 1,000*C for between about 15 minutes and 1 hour.
Claim 9
Dependent Claim
37 words
In a method as described in claim 1, wherein: said semiconductor material is silicon, and said capping material is a layer of silicon doped with atoms similar to those that were ion implanted into said semiconductor material.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |