EP0316165A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A method of trench isolation
Assignee: Seiko Instruments Inc
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Filing: 1988-11-10
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Granted: —
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Expires: 2008-11-10
Abstract
Abstract A method of trench isolation comprising the steps of forming an ion implanted layer (4) in a region of a semi-conductor substrate (1) and providing a trench (5) in the ion implanted layer.
Inventors
- 👤 Takashi Hosakao
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 21:25
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/014; H10W10/0148; H10W10/041; H10W10/10; H10W10/17; H10W10/40
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
33 words
A method of trench isolation characterised by the steps of forming an ion implanted layer (4) in a region of a semi-conductor substrate (1), and providing a trench in said ion implanted layer.
Claim 2
Independent Claim
33 words
A method of trench isolation characterised by the steps of forming an ion implanted layer (4) in a region of a semi-conductor substrate (1), and providing a trench in said ion implanted layer.
Claim 3
Dependent Claim
87 words
A method as claimed in claim 1 characterised in that said step of forming the ion implanted layer (4) comprises the steps of forming an insulation film (2) on the semi-conductor substrate (1), depositing a photo-resist (3) with a window in the region where the trench (5) is to be formed, etching said insulation film (2), forming the ion implanted layer in the area confined by the window by ion implantation with ion energy ranging from a relatively low energy level to a relatively high energy level.
Claim 4
Dependent Claim
51 words
A method as claimed in claim 2 characterised in that the step of forming the ion implanted layer comprising the step of changing the acceleration energy for ion implantation between a relatively low energy level and a relatively high energy level for providing a desired doping profile for the trench (5).
Claim 5
Dependent Claim
61 words
A method as claimed in claim 2 or 3, characterised in that the step of forming the ion implanted layer comprises the step of controlling the amount of implanting ions to provide either a substantially vertically uniform doping profile or a substantially vertically graded doping profile at the region of the semi-conductor substrate where the trench (5) is to be provided.
Claim 6
Independent Claim
28 words
A method as claimed in any preceding claim characterised by using a material having a high capacity to prevent ions passing therethrough as a mask for ion implantation.
Claim 7
Independent Claim
42 words
A method as claimed in any of claims 2 to 5 characterised in that the step of ion implanting is carried out at an implantation angle of ± 5° or less from a normal to the surface of the semi-conductor substrate (1).
References Cited (Backward Citations)
No citation records indexed.
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