← Back to Patent Explorer
US4899195A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of exposing a peripheral part of wafer

Assignee: Ushio Denki KK
•
Filing: 1988-12-21
•
Granted: 1990-02-06
•
Expires: 2008-12-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method of exposing a peripheral part of wafer is used for a fine pattern formation process in the processing of ICs, LSIs and other electronics elements, to remove, in a development step, an unncessary portion of a photoresist coated on a semiconductor substrate, typically a silicon wafer, or a substrate consisting of a dielectric, a metal or an insulator, from a peripheral part of the substrate. In the method for exposing a peripheral part of wafer, the wafer edge is detected using a sensor, and the light emission end of an optical fiber lightguide is controlled to expose a fixed distance from the edge of wafer according to a signal from the sensor. It is thus possible to expose a peripheral part of wafer having a predetermined width with high accuracy. In addition, the wafer centering mechanism and orientation flat detection/positioning mechanism employed in the prior art are unncessary. It is thus possible to provide a method exposing a peripheral part of wafer which can greatly reduce the processing time and has extremely high accuracy and efficiency.

Inventors

  • 👤 Manabu Gotoh

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 23:37
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70691; G03F7/20; G03F7/2022; G03F7/2026; G03F7/2028

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 68 words
A method of exposing a peripheral part of wafer which comprises, turning a wafer on which photoresist coated, exposing a peripheral part of said wafer to light guided by optical fiber lightguide, detecting the edge of said wafer by sensor, and controlling the light emission end of said optical fiber lightguide to expose a fixed distance from the edge of said wafer according to signal from said sensor.
Claim 2
Independent Claim 68 words
A method of exposing a peripheral part of wafer which comprises, turning a wafer on which photoresist coated, exposing a peripheral part of said wafer to light guided by optical fiber lightguide, detecting the edge of said wafer by sensor, and controlling the light emission end of said optical fiber lightguide to expose a fixed distance from the edge of said wafer according to signal from said sensor.
Claim 3
Dependent Claim 10 words
Said control is accomplished by servo mechanism in claim 1.

References Cited (Backward Citations)

US3449046A Cited
US3734612A Cited
US3836246A Cited
US4008954A Cited
US4477182A Cited
EP0123153A2 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-02-05 1993-08-07 1994-02-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-02-05 1997-08-07 1998-02-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-02-05 2001-08-07 2002-02-06 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag