A series of experiments was run to determine the scope, magnitude and possible solution to the frequently observed proximity effect on CD uniformity, which has become an acute problem in submicron processing. The matrix of experiments compared linewidth control for lines that were in an isolated location versus lines in high-density locations. The effects of g- line versus i-line exposure, substrate type, softbake temperature, post-exposure bake temperature, developer strength, and develop time on linewidth control were measured for Dynachem's NovaTM 2050 and EL 2015. These two resists represent examples of conventional diazoquinone/novolac g-line and g/i-line resists, respectively. Additionally, the effects of actinic dyes on proximity effects were measured by evaluating the dyed versions of the aforementioned resists, NovaTM 2050 AR and EL 2015 0.5 AN. Actinic dyes were initially introduced to control antireflective notching on metal substrates, but have now been shown with this work to have an effect on the isolated versus dense line phenomenon. The matrix of experiments used was a full factorial statistical design. When the results were collated and analyzed by the software package RS/1, the relative effects of each parameter on CD control was assessed. The statistical data, graphs and predicted best processes for various resist/dye/substrate combinations are presented. This data provides general guidelines for the control of the proximity effect for 0.8 micrometers g-line and i-line processes.

Date Published: 1 July 1991
PDF: 11 pages
Proc. SPIE 1463, Optical/Laser Microlithography IV, (1 July 1991); doi: 10.1117/12.44810

Published in SPIE Proceedings Vol. 1463:
Optical/Laser Microlithography IV
Victor Pol, Editor(s)