Devices and methods for reading identification marks on semiconductor wafers
1 Assignment
0 Petitions
Accused Products
Abstract
Methods and apparatus for machine reading of identification marks incised on semiconductor wafers. Preferred apparatus makes it possible to view the mark either as a dark image on a light background (which is in itself novel) or as a light image on a dark background. Using a television camera and an optical character reader, the viewing method can be changed automatically if a preset confidence level is not reached, and provides a signal if neither method (or the combination of the two methods) gives a satisfactory result. The method is particularly useful for successively reading the identification marks on a number of wafers stacked in a cassette. Preferred apparatus for such reading comprises a wafer support which can be pushed upwards from underneath the cassette so that the wafer to be identified rests on one ledge of the support and the adjacent wafer rests on another higher ledge on the support, thus exposing and precisely locating the identification mark on the first wafer.
-
Citations
0 Claims
Specification
-
- Resources
-
Current AssigneeHine Design Incorporated
-
Original AssigneeHine Design Incorporated
-
InventorsHine, Derek L., Krolak, Michael
-
Primary Examiner(s)Mancuso, Joseph
-
Assistant Examiner(s)COUSO, YON JUNG
-
Application NumberUS07/597,082Time in Patent Office1,135 DaysField of Search382/8, 382/1, 382/65, 382/48, 382/28, 358/101, 358/106, 350/345, 350/359, 350/526, 356/338US Class Current382/145CPC Class CodesG06K 7/10861 sensing of data fields affi...G06V 10/147 Details of sensors, e.g. se...G06V 10/22 by selection of a specific ...Y10S 414/138 Wafers positioned verticall...
