Method of efficiently laser marking singulated semiconductor devices

United States Patent [w]

Canella

US005986235A [ii] Patent Number: 5,986,235 [45] Date of Patent: Nov. 16,1999

[54] METHOD OF EFFICIENTLY LASER MARKING SINGULATED SEMICONDUCTOR DEVICES

[75] Inventor: Robert L. Canella, Meridian, Id.

[73] Assignee: Micron Electronics, Inc., Nampa, Id.

[21] Appl. No.: 08/897,774 [22] Filed: Jul. 21, 1997

Related U.S. Application Data

[62] Division of application No. 08/590,919, Jan. 24, 1996.

[51] Int. CI. B23K 26/00

[52] U.S. CI 219/121.68; 219/121.82;

219/121.84

[58] Field of Search 219/121.68, 121.69,

219/121.82, 121.83, 121.84, 121.85

[56] References Cited

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A laser marking apparatus and method for marking the surface ol a singulated article such as a semiconductor chip are described herein. Semiconductor chips are led along inclined, parallel tracks to a laser marking field where they are subsequently marked by a laser beam. As the laser beam is marking chips associated with one track, chips associated with other tracks that have already been marked are replaced by unmarked chips. In this manner, the laser is continually being used to mark semiconductor chips without having to wait for unmarked chips to move to the marking location.

34 Claims, 7 Drawing Sheets