Claims
- 1. A method for identifying and tracking wafers in a wafer fabrication facility, comprising the steps of:
- inscribing a unique bar code on a process side of each of the wafers;
- loading a plurality of said inscribed wafers in a cassette;
- arranging the wafers in the cassette along a presentation axis to simultaneously expose the bar code on each of the wafers;
- positioning and controlling a laser scanner along a first, a second and a third axis to scan the bar code on each of the wafers along the presentation axis.
- 2. The method, as set forth in claim 1, wherein said laser scanner positioning step includes the step of varying an angular and spatial position of said laser scanner with respect to said wafers.
- 3. The method, as set forth in claim 1, further comprising the step of sensing the presence of the wafers.
Parent Case Info
This application is a Continuation of application Ser. No. 08/475.723 , filed Jun. 7, 1995 now abandoned.
US Referenced Citations (4)
Foreign Referenced Citations (3)
Number |
Date |
Country |
0004870 |
Jan 1981 |
JPX |
4185397 |
Oct 1992 |
JPX |
5144147 |
Sep 1993 |
JPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
475723 |
Jun 1995 |
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