The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 1990
Filed:
Nov. 28, 1988
Robert J Carlson, Brooklyn Park, MN (US);
Michael D Grimm, Minneapolis, MN (US);
Abstract
To provide for improved uniformity of photoresist developing of silicon wafers, developer solution is injected via an inlet port through a set of holes in a surface in a chuck and distributed across the wafer thereby developing the wafer pattern. A second set of holes in the same surface of the chuck act as exhaust outlets for the used developer. An end point detector is associated with an outlet duct. This design provides great uniformity potential since it is a single wafer system, and the holes and fluid flows can be adjusted as needed. Also, this design requires minimum developer volume which means end point detection can take place using the waste developer at the outlet. Test such as optical density or color, PH or normality, density, or others can detect photoresist content in effluent to determine completion.