EP0278159A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of manufacturing a semiconductor device comprising an isolation structure
Assignee: Plessey Overseas Ltd
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Filing: 1987-11-13
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Granted: —
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Expires: 2007-11-13
Abstract
Abstract A method (fig. 3) where following etch definition of a trench (9) in silicon, the walls of this trench (9) are coated with a layer of polysilicon (11) and the latter oxidised (13). The trench (9) is then infilled e.g. with deposited polysilicon (15). The walls of the trench (9) may be oxidised to provide a thin oxide film (12) prior to polysilicon (11) deposition.
Inventors
- 👤 Martin Ceredig Roberts
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 22:57
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/041; H10W10/40
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
109 words
A method of semiconductor device manufacture including the steps of:- providing a substrate (3) of single crystal silicon material having a thin layer covering (5) of nitride and over this a layer (7) of masking material; etching in this composite structure (3, 5, 7) a trench (9) extending into the silicon substrate (3); and removing the masking material (7); which method is characterising by the following steps:- depositing on the exposed nitride layer (5), and exposed silicon trench walls and base (9), a conformal thin layer (11) of polysilicon; oxidising the layer (11) of polysilicon at a temperature in the range 950° - 1050°C; and finally, in-filling the trench.
Claim 2
Independent Claim
109 words
A method of semiconductor device manufacture including the steps of:- providing a substrate (3) of single crystal silicon material having a thin layer covering (5) of nitride and over this a layer (7) of masking material; etching in this composite structure (3, 5, 7) a trench (9) extending into the silicon substrate (3); and removing the masking material (7); which method is characterising by the following steps:- depositing on the exposed nitride layer (5), and exposed silicon trench walls and base (9), a conformal thin layer (11) of polysilicon; oxidising the layer (11) of polysilicon at a temperature in the range 950° - 1050°C; and finally, in-filling the trench.
Claim 3
Dependent Claim
17 words
A method, as claimed in claim 1, wherein said masking material (7) is of deposited thick oxide.
Claim 4
Independent Claim
62 words
A method, as claimed in either one of the preceding claims, wherein a thin film (12) of oxide is grown thermally at the exposed silicon trench walls and base (9) prior to the step of . . . immediately preceded by a wet chemical light etch step that is performed to remove any damage at the surface of the etched trench (9).
Claim 5
Independent Claim
23 words
A method, as claimed in any one of the preceding claims, wherein finally polysilicon material (15) is deposited to infill the trench (9).
Claim 6
Dependent Claim
31 words
A method, as claimed in Claim 5, wherein the infill polysilicon material (15) is cut back to the level of the nitride layer (5), and the surface thereof is oxidised (13).
References Cited (Backward Citations)
No citation records indexed.
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