Patent US4082571A successfully refreshed from Google Patents.
US4082571A
Expired / Lapsed
US
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Process for suppressing parasitic components utilizing ion implantation prior to epitaxial deposition
Assignee: Siemens AG
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Filing: 1976-01-09
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Granted: 1978-04-04
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Expires: 1996-01-09
Abstract
Abstract A process for suppressing parasitic components, in particular parasitic diodes and transistors, in integrated circuits which have, in particular, inversely operated transistors, in which a semiconductor substrate of the first conductivity type as introduced therein a highly doped zone of a second conductivity type which is opposite to the first conductivity type and which extends to a surface of the semiconductor substrate. A semiconductor layer of the second conductivity type is epitaxially deposited on the surface and the semiconductor layer further has produced therein zones of differing conductivity type which form at least one component which is electrically insulated from adjacent components. Prior to the deposition of the semiconductor layer, at least one highly ohmic layer and/or a layer having a high density of recombination centers is introduced by ion implantation into the surface of the semiconductor substrate at points suitable for the suppression of the parasitic components which form subsequently due to the production of the zones of differing conductivity type in the semiconductor layer.
Inventors
- 👤 Juergen Graul
- 👤 Helmuth Murrmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:25
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10D; H10D62/00; H10D62/10; H10D62/113; H10D62/13; H10D62/137; H10D62/80; H10D62/83; H10D62/834; H10D84/00; H10D84/60; H10D84/63; H10P30/208; Y; Y10; Y10S; Y10S148/00; Y10S148/06; Y10S148/085
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
204 words
In a process for suppressing parasitic components, in particular parasitic diodes and transistors, in circuits which possess, in particular, inversely operated transistors, in which a highly doped zone of a second conductivity is introduced into and extends to a surface of a semiconductor substrate of a first conductivity type which is opposite the second conductivity type, in which a semiconductor layer of the second conductivity type is epitaxially deposited on the surface, and in which zones of differing conductivity types are produced in the semiconductor layer to form at least one component which is electrically insulated from adjacent components, the improvement therein comprising: prior to deposition of the semiconductor layer, forming a layer for controlling the number of charge carriers at parasitic pn junctions subsequently formed by the semiconductor layer and the zones produced therein by implanting ions into the surface of the semiconductor substrate at points suitable to suppress parasitic components while simultaneously chemically reacting the ions with the atoms of the substrate to form molecules, controlling the implantation energy to obtain an implantation concentration at the surface of the substrate which will not impair regeneration of the crystal lattice during a following healing step, and thermally healing the surface of the substrate.
Claim 2
Dependent Claim
204 words
In a process for suppressing parasitic components, in particular parasitic diodes and transistors, in circuits which possess, in particular, inversely operated transistors, in which a highly doped zone of a second conductivity is introduced into and extends to a surface of a semiconductor substrate of a first conductivity type which is opposite the second conductivity type, in which a semiconductor layer of the second conductivity type is epitaxially deposited on the surface, and in which zones of differing conductivity types are produced in the semiconductor layer to form at least one component which is electrically insulated from adjacent components, the improvement therein comprising: prior to deposition of the semiconductor layer, forming a layer for controlling the number of charge carriers at parasitic pn junctions subsequently formed by the semiconductor layer and the zones produced therein by implanting ions into the surface of the semiconductor substrate at points suitable to suppress parasitic components while simultaneously chemically reacting the ions with the atoms of the substrate to form molecules, controlling the implantation energy to obtain an implantation concentration at the surface of the substrate which will not impair regeneration of the crystal lattice during a following healing step, and thermally healing the surface of the substrate.
Claim 3
Dependent Claim
25 words
The improved process of claim 1, wherein the step of forming a layer is further defined as: implanting ions to form a highly ohmic layer.
Claim 4
Dependent Claim
25 words
The improved process of claim 1, wherein the step of forming a layer is further defined as: implanting ions to form high density recombination centers.
Claim 5
Dependent Claim
38 words
The improved process of claim 1, wherein the step of forming a layer is further defined as: implanting ions and forming therewith, in combination with lattice gaps in said substrate, ionized interstitial complexes which are difficult to heal.
Claim 6
Dependent Claim
19 words
The improved process of claim 4, wherein the step of implanting ions is further defined as: implanting oxygen ions.
Claim 7
Dependent Claim
20 words
The improved process of claim 1, wherein the step of forming a layer is further defined as: implanting oxygen ions.
Claim 8
Dependent Claim
20 words
The improved process of claim 1, wherein the step of forming a layer is further defined as: implanting carbon ions.
Claim 9
Dependent Claim
20 words
The improved process of claim 1, wherein the step of forming a layer is further defined as: implanting nitrogen ions.
Claim 10
Dependent Claim
33 words
The improved process of claim 1, wherein the step of implanting ions is further defined as: implanting nitrogen ions to obtain a maximum doping concentration of 5 × 10 21 cm -3 .
Claim 11
Dependent Claim
30 words
The improved process of claim 1, wherein the step of implanting ions and controlling implantation energy are further defined as: implanting nitrogen ions with an implantation energy of 150 keV.
Claim 12
Dependent Claim
30 words
The improved process of claim 10, wherein the step of implanting nitrogen ions is further defined as implanting nitrogen ions to obtain a concentration of 10 18 cm -3 .
Claim 13
Dependent Claim
28 words
The improved process of claim 11, wherein the step of thermally healing the surface is further defined as: healing the surface at a temperature of ≧ 1000° C.
Claim 14
Dependent Claim
66 words
The improved process of claim 14, comprising the further steps of: introducing ions of the second conductivity type into the substrate and of a higher diffusion coefficient than that of the doping material of the highly doped zone; and heating the substrate, subsequent to the deposition of the semiconductor layer, to cause the material of the higher diffusion coefficient to diffuse farther into the semiconductor layer.
References Cited (Backward Citations)
US3457632A
Cited
US3515956A
Cited
US3533857A
Cited
US3622382A
Cited
US3666548A
Cited
US3840409A
Cited
US3849204A
Cited
UST918008I4
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-03 | 1981-10-03 | 1982-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-03 | 1985-10-03 | 1986-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-03 | 1989-10-03 | 1990-04-04 | $7700.00 | Window Closed / Lapsed |