Patent EP0230648A2 successfully refreshed from Google Patents.
EP0230648A2
Expired / Lapsed
EP
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Method of forming an alignment mark
Assignee: NEC Corp
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Filing: 1986-12-23
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Granted: —
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Expires: 2006-12-23
Abstract
Abstract A method of forming an alignment mark for a semi-conductor wafer including the steps of forming an insulating film or a polycrystalline silicon film on a scribe line region of said semiconductor wafer, and providing a plurality of parallel grooves in the insulating film or the polycrystalline silicon film to form a plane reflection type diffraction grating.
Inventors
- 👤 Nobuo C/O Nec Corporation Honto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 18:29
CPC Classifications
H; H10; H10W; H10W46/00; H10W46/301; H10W46/501
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
54 words
A method of forming an alignment mark for a semiconductor wafer comprising the steps of forming an insulating film on a scribe line region of said semiconductor wafer, and providing a plurality of parallel grooves in said insulating film to form a plane reflection type diffraction grating which is used for said alignment mark.
Claim 2
Independent Claim
54 words
A method of forming an alignment mark for a semiconductor wafer comprising the steps of forming an insulating film on a scribe line region of said semiconductor wafer, and providing a plurality of parallel grooves in said insulating film to form a plane reflection type diffraction grating which is used for said alignment mark.
Claim 3
Dependent Claim
29 words
A method of forming an alignment mark according to claim 1 wherein a material of said insulating film is one selected from silicon oxide, silicon nitride, and polycrystalline silicon.
Claim 4
Dependent Claim
27 words
A method of forming an alignment mark according to claim 1 wherein said two steps are implemented by making use of the process for forming semiconductor element.
Claim 5
Dependent Claim
15 words
A semiconductor wafer comprising an alignment mark formed by the method described in claim 1.
References Cited (Backward Citations)
No citation records indexed.
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