EP0030457A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of manufacturing a silicon wafer with interior microdefects capable of gettering
Assignee: VLSI Technology Research Association
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Filing: 1980-12-04
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Granted: —
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Expires: 2000-12-04
Abstract
Abstract A semiconductor wafer is first heat treated in a non-oxidising atmosphere in a temperature in the range from 950°C to 1300 °C to diffuse out oxygen (0 2 ) from near the surfaces 1 and 2 of the wafer (oxygen density shown by broken line in Figure 3B). The wafer is then heat treated at a temperature in the range from 600 °C to 800 °C to create a high density of defects 3 (defect density shown by solid lines in Figures 3B and 3D) which are capable of gettering, in the interior of the wafer.
Inventors
- 👤 Kazutoshi Nagasawa
- 👤 Seigo Kishino
- 👤 Yoshiaki Matsushita
- 👤 Masaru Kanamori
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 03:23
CPC Classifications
H; H10; H10P; H10P36/00; H10P36/20; Y; Y10; Y10S; Y10S148/00; Y10S148/128
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
76 words
A method of manufacturing a semiconductor device, comprising forming in a semiconductor wafer, near a surface thereof, a denuded zone free of microdefects, and forming in the interior of the wafer microdefects capable of gettering, characterised by: heating treating the wafer in a first temperature range, the limits of which are 950°C and 1300°C, in a non-oxidising atmosphere, then heat treating the wafer in a second temperature range, the limits of which are 600°C and 800°C.
Claim 2
Independent Claim
76 words
A method of manufacturing a semiconductor device, comprising forming in a semiconductor wafer, near a surface thereof, a denuded zone free of microdefects, and forming in the interior of the wafer microdefects capable of gettering, characterised by: heating treating the wafer in a first temperature range, the limits of which are 950°C and 1300°C, in a non-oxidising atmosphere, then heat treating the wafer in a second temperature range, the limits of which are 600°C and 800°C.
Claim 3
Dependent Claim
25 words
A method as claimed in claim 1, wherein the heat treating of the wafer in the first temperature range lasts for 10 minutes or more.
Claim 4
Dependent Claim
27 words
A method as claimed in claim 1 or 2, wherein the heat treating of the wafer in the first temperature range lasts for less than 70 hours.
Claim 5
Dependent Claim
28 words
A method as claimed in claim 1, 2 or 3, wherein the heat treating of the wafer in the second temperature range lasts for 1 hour or more.
Claim 6
Independent Claim
30 words
A method as claimed in any preceding claim, wherein the heat treating of the wafer in the first temperature range takes places at 1050 C and lasts for 4 hours.
Claim 7
Independent Claim
28 words
A method as claimed in any preceding claim, wherein the heat treating of the wafer in the second temperature range takes-place at 650°C and lasts for 16 hours.
Claim 8
Independent Claim
23 words
A method as claimed in any preceding claim, wherein active and/or passive elements of the semiconductor device are formed in the denuded zone.
Claim 9
Independent Claim
37 words
A method as claimed in any one of claims 1 to 6, wherein an epitaxial layer is formed on the denuded zone, and active and/or passive elements of the. semiconductor device are formed on the epitaxial layer.
Claim 10
Independent Claim
16 words
A method as claimed in any preceding claim, wherein the semiconductor wafer is a silicon wafer.
Claim 11
Dependent Claim
23 words
A method as claimed in claim 9, wherein the silicon wafer is a (100) single crystal CZ wafer made by the Czochralski method.
Claim 12
Dependent Claim
13 words
A semiconductor device manufactured by a method as claimed in any preceding claim.
References Cited (Backward Citations)
No citation records indexed.
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