EP0107902A2
Expired / Lapsed
EP
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A method for fabricating isolation regions in semiconductor devices
Assignee: Fujitsu Ltd
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Filing: 1983-09-16
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Granted: —
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Expires: 2003-09-16
Abstract
Abstract An isolation groove (16) is formed in a substrate. The inner surface of the isolation groove is coated by an insulation film (17). Then the groove is buried by polycrystal semiconductor material (18). <??>Any polycrystai material (18) which is deposited on the surface of substrate is etched off. At the same time the polycrystal material in the groove is also etched to a specific depth from the surface. <??>Insulation film (19) is then grown so as to fill up the groove again. The surface is polished or etched to provide a flat surface.
Inventors
- 👤 Hiroshi C/O Fujitsu Limited Goto
- 👤 Akira C/O Fujitsu Limited Tabata
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 16:48
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/041; H10W10/40
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
60 words
A method of fabricating an isolation region in a semiconductor substrate, including (a) forming an isolation groove in the substrate; (b) coyering the inner surface of the groove with an insulating layer; (c) filling the groove to a selected depth with polycrystal semiconductor material; (d) forming insulating material on the polycrystal semiconductor material, to fill the remainder of the groove.
Claim 2
Independent Claim
60 words
A method of fabricating an isolation region in a semiconductor substrate, including (a) forming an isolation groove in the substrate; (b) coyering the inner surface of the groove with an insulating layer; (c) filling the groove to a selected depth with polycrystal semiconductor material; (d) forming insulating material on the polycrystal semiconductor material, to fill the remainder of the groove.
Claim 3
Dependent Claim
30 words
A method as claimed in claim 1, wherein (c) comprises: .completely filling the groove with the polycrystal semiconductor material, and etching off the polycrystal semiconductor material to the selected depth.
Claim 4
Dependent Claim
20 words
A method as claimed in claim 2, wherein the polycrystal semiconductor material is etched off by a wet etching process.
Claim 5
Dependent Claim
24 words
A method as claimed in claim 1, 2 or 3, wherein the insulating material is formed on the polycrystal semiconductor material by bias sputtering.
Claim 6
Dependent Claim
24 words
A method as claimed in claim 1,2, or 3 wherein the insulating material is formed on the polycrystal semiconductor material by chemical vapor deposition.
Claim 7
Independent Claim
15 words
A method as claimed in any preceding claim, wherein the isolation groove is a U-groove.
Claim 8
Dependent Claim
25 words
A method as claimed in claim 6, wherein a highly doped region is formed beneath the bottom of the U-groove to provide a channel stopper.
Claim 9
Independent Claim
52 words
A method as claimed in any preceding claim, wherein the selected depth is in the range 0.2 µm to 1 µm. A method as claimed in any preceding claim , wherein the substrate is silicon, the insulating layer and the insulating material are silicon dioxide, and the polycrystal semiconductor material is polysilicon.
Claim 10
Independent Claim
56 words
A method as claimed in any preceding claim, further comprising : (e) polishing the surface of the substrate to remove such insulating material from the surface, or (f) wet etching, using hydrofluoric acid, or dry etching, using tri-fluoro methane gas, the surface of the substrate to remove such insulating material from the surface of the substrate.
References Cited (Backward Citations)
No citation records indexed.
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