Share Email Print

Proceedings Paper

Differences between wafer and bake plate temperature uniformity in proximity bake: a theoretical and experimental study
Author(s): Natarajan Ramanan; Austin Kozman; James B. Sims
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

As the lithography industry moves toward finer features, specifications on temperature uniformity of the bake plates are expected to become more stringent. Consequently, aggressive improvements are needed to conventional bake station designs to make them perform significantly better than current market requirements. To this end, we have conducted a rigorous study that combines state-of-the-art simulation tools and experimental methods to predict the impact of the parameters that influence the uniformity of the wafer in proximity bake. The key observation from this detailed study is that the temperature uniformity of the wafer in proximity mode depends on a number of parameters in addition to the uniformity of the bake plate itself. These parameters include the lid design, the air flow distribution around the bake chamber, bake plate design and flatness of the bake plate and wafer. By performing careful experimental studies that were guided by extensive numerical simulations, we were able to understand the relative importance of each of these parameters. In an orderly fashion, we made appropriate design changes to curtail or eliminate the nonuniformity caused by each of these parameters. After implementing all these changes, we have now been able to match or improve the temperature uniformity of the wafer in proximity with that of a contact measurement on the bake plate. The wafer temperature uniformity is also very close to the theoretically predicted uniformity of the wafer.

Paper Details

Date Published: 23 June 2000
PDF: 9 pages
Proc. SPIE 3999, Advances in Resist Technology and Processing XVII, (23 June 2000); doi: 10.1117/12.388375
Show Author Affiliations
Natarajan Ramanan, FSI International, Inc. (United States)
Austin Kozman, FSI International, Inc. (United States)
James B. Sims, FSI International, Inc. (United States)

Published in SPIE Proceedings Vol. 3999:
Advances in Resist Technology and Processing XVII
Francis M. Houlihan, Editor(s)

© SPIE. Terms of Use
Back to Top