US3901735A
Expired / Lapsed
US
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Integrated circuit device and method utilizing ion implanted and up diffusion for isolated region
Assignee: National Semiconductor Corp
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Filing: 1973-09-10
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Granted: 1975-08-26
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Expires: 1993-09-10
Abstract
Abstract An integrated circuit device including a transistor within an isolation region, said isolation region being formed by an ion implantation of a first conductivity type dopant into the device substrate of said first conductivity type, an epitaxial layer of a second conductivity type being grown on said substrate, and a second portion of said isolation region being formed by a diffusion of said first conductivity type dopant down through the epitaxial layer, said ion implanted dopant diffusing up to overlap with the down diffusion dopant to form the isolation region. Several forms of transistors including lateral devices and vertical devices are included on the integrated circuit device.
Inventors
- 👤 James L Dunkley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:45
CPC Classifications
H; H10; H10W; H10W15/00; H10W10/00; H10W10/01; H10W10/031; H10W10/30; H10W15/01; Y; Y10; Y10S; Y10S148/00; Y10S148/037
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
174 words
THE METHOD FOR MAKING A TRANSISTOR IN THE SEMICONDUCTOR SUBTRATE OF AN INTEGRATED CIRCUIT DEVICE COMPRISING THE STEPS OF FORMING A FIRST PORTION OF AN ISOLATION REGION OF A FIRST CONDUCTIVITY TYPE IN A SEMICONDUCTOR SUBSTRATE OF SAID FIRST CONDUCTIVITY TYPE BY THE ION IMPLANTATION OF A DOPANT OF SAID FIRST CONDUCTIVE TYPE INTO THE SURFACE OF THE SUBSTRATE, GROWING AN EPITAXAL LAYER OF A SECOND CONDUCTIVITY TYPE ON THE SURFACE OF SAID SUBSTRATE AND OVER SAID ION IMPLANTED REGION, FOMING A SECOND PORTION OF SAID ISOLATION REGION IN SAID EPITAXIAL LAYER BY THE DIFFUSION OF A DOPANT OF SAID FIRST CONDUCTIVITY TYPE DOWN INTO THE EPITAXIAL LAYER, SAID ION IMPLANTED DOPANT DIFFUSING FROM SAID SUBSTRATE UP INTO SAID EPITAXIAL LAYER UNTIL SAID DOWN DIFFUSION AND SAID UP DIFFUSION OVERLAP, FORMING THE BASE REGION OF SAID TRANSISTOR BY DIFFUSION OF A DOPANT OF SAID FIRST CONDUCTIVITY TYPE IN SAID EPITAXIAL LAYER, AND FORMING THE EMITTER REGION OF SAID TRANSISTOR BY THE DIFFUSION OF A DOPANT OF SAID SECOND CONDUCTIVITY TYPE INTO SAID BASE REGION.
Claim 2
Independent Claim
174 words
THE METHOD FOR MAKING A TRANSISTOR IN THE SEMICONDUCTOR SUBTRATE OF AN INTEGRATED CIRCUIT DEVICE COMPRISING THE STEPS OF FORMING A FIRST PORTION OF AN ISOLATION REGION OF A FIRST CONDUCTIVITY TYPE IN A SEMICONDUCTOR SUBSTRATE OF SAID FIRST CONDUCTIVITY TYPE BY THE ION IMPLANTATION OF A DOPANT OF SAID FIRST CONDUCTIVE TYPE INTO THE SURFACE OF THE SUBSTRATE, GROWING AN EPITAXAL LAYER OF A SECOND CONDUCTIVITY TYPE ON THE SURFACE OF SAID SUBSTRATE AND OVER SAID ION IMPLANTED REGION, FOMING A SECOND PORTION OF SAID ISOLATION REGION IN SAID EPITAXIAL LAYER BY THE DIFFUSION OF A DOPANT OF SAID FIRST CONDUCTIVITY TYPE DOWN INTO THE EPITAXIAL LAYER, SAID ION IMPLANTED DOPANT DIFFUSING FROM SAID SUBSTRATE UP INTO SAID EPITAXIAL LAYER UNTIL SAID DOWN DIFFUSION AND SAID UP DIFFUSION OVERLAP, FORMING THE BASE REGION OF SAID TRANSISTOR BY DIFFUSION OF A DOPANT OF SAID FIRST CONDUCTIVITY TYPE IN SAID EPITAXIAL LAYER, AND FORMING THE EMITTER REGION OF SAID TRANSISTOR BY THE DIFFUSION OF A DOPANT OF SAID SECOND CONDUCTIVITY TYPE INTO SAID BASE REGION.
Claim 3
Dependent Claim
23 words
The method as claimed in claim 1 wherein said first conductivity type is P type and said second conductivity type is N type.
Claim 4
Dependent Claim
65 words
The method as claimed in claim 1 including also making a lateral transistor on said substrate spaced apart from said transistor comprising the steps of forming an emitter region and a collector region in said epitaxial layer by the diffusion of said dopant of said first conductivity type down into said epitaxial layer at the time of forming said second portion of said isolation region.
Claim 5
Dependent Claim
23 words
The method as claimed in claim 3 wherein said first conductivity type is P type and said second conductivity type is N type.
Claim 6
Dependent Claim
81 words
The method as claimed in claim 1 including also making a vertical transistor on said substrate spaced apart from said transistor comprising the steps of forming an emitter region in said epitaxial layer by the diffusion of said dopant of said first conductivity type down into said epitaxial layer at the time of forming said second portion of said isolation region, said epitaxial layer serving as the base region and said substrate serving as the collector region for the vertical transistor.
Claim 7
Dependent Claim
23 words
The method as claimed in claim 5 wherein said first conductivity type is P type and said second conductivity type is N type.
Claim 8
Dependent Claim
126 words
The method as claimed in claim 1 including also making a vertical transistor on said substrate spaced apart from said transistor comprising the steps of forming a collector region in said substrate layer by the ion implantation of said dopant of said first conductivity type in said substrate at the time of forming said first portion of said isolation region in said substrate, said epitaxial layer formed on said substrate serving as the base region and said substrate and ion implanted collector region serving as the collector region for the vertical transistor, and forming an emitter region in said epitaxial layer by the diffusion of a region of said first conductivity type into said epitaxial layer at the time of formation of said first base region.
Claim 9
Dependent Claim
23 words
The method as claimed in claim 7 wherein said first conductivity type is P type and said second conductivity type is N type.
Claim 10
Dependent Claim
169 words
The method as claimed in claim 1 including also making a vertical transistor on said substrate spaced apart from said transistor comprising the steps of diffusing a heavily doped buried layer region of said second conductivity type into said substrate prior to said ion implantation, forming a collector layer within said heavily doped buried layer region by the ion implantation of a layer of said first conductivity type at the time of formation of said ion implanted first portion of said isolation region, said epitaxial layer being grown over said latter two layers, forming a collector connection plug down through said epitaxial layer and into contact with said ion implanted collector layer, forming an emitter region in said epitaxial layer by the diffusion of a dopant of said first conductivity type during formation of said first base region, said epitaxial layer serving as the base region and said collector layer serving as the collector region for the vertical transistor, and forming a base connection region to said epitaxial layer.
Claim 11
Dependent Claim
23 words
The method as claimed in claim 9 wherein said first conductivity type is P type and said second cOnductivity type is N type.
Claim 12
Independent Claim
212 words
The method for making a transistor in the semiconductor substrate of an integrated circuit device, said substrate being of a first conductivity type, comprising the steps of diffusing a heavily doped buried layer region of a second conductivity type material into the surface of a semiconductor substrate, forming a first portion of an isolation region in said substrate by the ion implantation of a dopant of said first conductivity type, growing an epitaxial layer of said second conductivity type on the surface of said substrate, forming a second portion of said isolation region in said epitaxial layer by the diffusion of a dopant of said first conductivity type down into the epitaxial layer, said ion implanted dopant diffusing from said substrate up into said epitaxial layer until said down diffusion and said up diffusion overlap, forming the base region of said transistor by diffusion of a dopant of said first conductivity type in the surface of said epitaxial layer, forming the emitter region of said transistor by the diffusion of a dopant of said second conductivity type into said base region, and forming a collector connection region in the surface of said epitaxial layer by the diffusion of a dopant of said second conductivity type into the surface of said epitaxial layer.
Claim 13
Independent Claim
212 words
The method for making a transistor in the semiconductor substrate of an integrated circuit device, said substrate being of a first conductivity type, comprising the steps of diffusing a heavily doped buried layer region of a second conductivity type material into the surface of a semiconductor substrate, forming a first portion of an isolation region in said substrate by the ion implantation of a dopant of said first conductivity type, growing an epitaxial layer of said second conductivity type on the surface of said substrate, forming a second portion of said isolation region in said epitaxial layer by the diffusion of a dopant of said first conductivity type down into the epitaxial layer, said ion implanted dopant diffusing from said substrate up into said epitaxial layer until said down diffusion and said up diffusion overlap, forming the base region of said transistor by diffusion of a dopant of said first conductivity type in the surface of said epitaxial layer, forming the emitter region of said transistor by the diffusion of a dopant of said second conductivity type into said base region, and forming a collector connection region in the surface of said epitaxial layer by the diffusion of a dopant of said second conductivity type into the surface of said epitaxial layer.
Claim 14
Dependent Claim
22 words
The method as claimed in claim 11 wherein said first conductivity type is P type and said second conductivity is N type.
Claim 15
Dependent Claim
67 words
The method as claimed in claim 11 including also making a lateral transistor on said substrate spaced apart from said transistor comprising the steps of forming a second emitter region and an associated collector region in said epitaxial layer by the diffusion of said dopant of said first conductivity type down into said epitaxial layer at the time of forming said second portion of said isolation region.
Claim 16
Dependent Claim
23 words
The method as claimed in claim 13 wherein said first conductivity type is P type and said second conductivity type is N type.
Claim 17
Dependent Claim
81 words
The method as claimed in claim 11 including also making a vertical transistor on said substrate spaced apart from said transistor comprising the steps of forming an emitter region in said epitaxial layer by the diffusion of said dopant of said first conductivity type down into said epitaxial layer at the time of forming said second portion of said isolation region, said epitaxial layer serving as the base region and said substrate serving as the collector region for the vertical transistor.
Claim 18
Dependent Claim
23 words
The method as claimed in claim 15 wherein said first conductivity type is P type and said second conductivity type is N type.
Claim 19
Dependent Claim
126 words
The method as claimed in claim 11 including also making a vertical transistor on said substrate spaced apart from said transistor comprising the steps of forming a collector region in said substrate layer by the ion implantation of said dopant of said first conductivity type in said substrate at the time of forming said first portion of said isolation region in said substrate, said epitaxial layer formed on said substrate serving as the base region and said substrate and ion implanted collector region serving as the collector region for the vertical transistor, and forming an emitter region in said epitaxial layer by the diffusion of a region of said first conductivity type into said epitaxial layer at the time of formation of said first base region.
Claim 20
Dependent Claim
169 words
The method as claimed in claim 11 including also making a vertical transistor on said substrate spaced apart from said transistor comprising the steps of diffusing a heavily doped buried layer region of said second conductivity type into said substrate prior to said ion implantation, forming a collector layer within said heavily doped buried layer region by the ion implantation of a layer of said first conductivity type at the time of formation of said ion implanted first portion of said isolation region, said epitaxial layer being grown over sAid latter two layers, forming a collector connection plug down through said epitaxial layer and into contact with said ion implanted collector layer, forming an emitter region in said epitaxial layer by the diffusion of a dopant of said first conductivity type during formation of said first base region, said epitaxial layer serving as the base region and said collector layer serving as the collector region for the vertical transistor, and forming a base connection region to said epitaxial layer.
Claim 21
Dependent Claim
23 words
The method as claimed in claim 18 wherein said first conductivity type is P type and said second conductivity type is N type.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |