US3767487A
Expired / Lapsed
US
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Method of producing igfet devices having outdiffused regions and the product thereof
Assignee: US Philips Corp
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Filing: 1971-11-05
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Granted: 1973-10-23
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Expires: 1991-11-05
Abstract
Abstract A method of manufacturing a semiconductor device having an insulated gate field effect transistor in which a second region of the second conductivity type is indiffused in a first region of the first conductivity type and source and drain zones of the first conductivity type are provided in said second region. According to the invention, after the indiffusion, the doping material of the second region is outdiffused in an atmosphere of reduced pressure, preferably in a vacuum, in which a zone of maximum doping concentration is formed which may advantageously be used as a channel stopper and the source and drain zones are provided in the part of the second region having a doping concentration which increases from the surface. The method is preferably used for the manufacture of structures having complementary field effect transistors.
Inventors
- 👤 W Steinmaier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:34
CPC Classifications
H; H10; H10P; H10P95/00; H10D; H10D84/00; H10D84/01; H10D84/0107; H10D84/0109; H10D84/02; H10D84/03; H10D84/038; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10D84/858; H10D99/00; Y; Y10; Y10S; Y10S148/00; Y10S148/037; Y10S148/053; Y10S148/085
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
19 words
A method as recited in claim 1, wherein said second conductivity type doping material is outdiffused in a vacuum.
Claim 2
Dependent Claim
24 words
A method as recited in claim 1, wherein said space contains semiconductor material which is substantially free from said second conductivity type doping material.
Claim 3
Dependent Claim
31 words
A method as recited in claim 1, wherein said source and drain zones of said first conductivity type are provided entirely in said positive dopant gradient portion of said second region.
Claim 4
Dependent Claim
64 words
A method as recited in claim 1, wherein said second conductivity type doping material is outdiffused from only said portion of said surface part located at said second region and at least the edge of said surface part is covered by a masking layer during said outdiffusion step, said masking layer impeding the outdiffusion of said second conductivity type doping material from said edge.
Claim 5
Dependent Claim
28 words
A method as recited in claim 5, wherein said introduction and outdiffusion of said second conductivity type doping material are carried out while using the same diffusion mask.
Claim 6
Dependent Claim
52 words
A method as recited in claim 5, wherein said second conductivity type doping material is outdiffused from at least two mutually separate portions of said surface part located at said second region and source and drain zones of various insulated gate field effect transistors are provided in respective ones of said portions.
Claim 7
Dependent Claim
48 words
A method as recited in claim 1, comprising the steps of providing a complementary insulated gate field effect transistor in said first region, said complementary transistor comprising source and drain zones of said second conductivity type adjoining said semiconductor surface and said first region adjoining said second region.
Claim 8
Dependent Claim
25 words
A method as recited in claim 8, wherein said second region constitutes one of a source and drain zone of said complementary field effect transistor.
Claim 9
Dependent Claim
53 words
A method as recited in claim 1, comprising the steps of simultaneously providing in said semiconductor body a base zone for a bipolar transistor and said second region and simultaneously providing in said semiconductor body an emitter zone for said bipolar transistor and said source and drain zones located in said second region.
Claim 10
Dependent Claim
23 words
A method as recited in claim 1, wherein said second region is laterally surrounded entirely by said first region within said semiconductor body.
Claim 11
Dependent Claim
97 words
A method as recited in claim 1, wherein said semiconductor body comprises a substrate region of said second conductivity type and said first surface region comprises an epitaxial layer of said first conductivity type, said method comprising the further step of forming isolation zones in said layer so as to divide said layer into islands, said isolation zones being of said second conductivity type and extending from said surface to said substrate region, said isolation zones and said second region being provided simultaneously in the same diffusion step by indiffusion of said second conductivity type doping material.
Claim 12
Dependent Claim
17 words
A method as recited in claim 1, wherein said second conductivity type material is an acceptor impurity.
Claim 13
Dependent Claim
15 words
A method as recited in claim 13, wherein said semiconductor body consists essentially of silicon.
Claim 14
Dependent Claim
84 words
A method as recited in claim 14, wherein the surface concentration of the acceptor impurity which is boron during the introduction into said surface region and the time and temperature of the outdiffusion are chosen to be so that after the outdiffusion step of the maximum doping concentration in said second region is at least 1018 atoms/ccm and that the doping concentration at said surface part of said second region at which outdiffusion took place is at most equal to 5 X 1016 atoms/ccm.
Claim 15
Dependent Claim
25 words
A method as recited in claim 1, further comprising the step of forming over said channel region a gate electrode consisting essentially of polycrystalline silicon.
Claim 16
Dependent Claim
12 words
A semiconductor device produced according to the method recited in claim 1.
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) | 1976-10-22 | 1977-04-23 | 1977-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-22 | 1981-04-23 | 1981-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-22 | 1985-04-23 | 1985-10-23 | $7700.00 | Window Closed / Lapsed |