Share Email Print

Proceedings Paper

Investigation of reflective notching with massively parallel simulation
Author(s): Karim H. Tadros; Andrew R. Neureuther; John Kenneth Gamelin; Roberto Guerrieri
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

A massively parallel simulation program TEMPEST is used to investigate the role of topography in generating reflective notching and to study the possibility of reducing effects through the introduction of special properties of resists and antireflection coating materials. The emphasis is on examining physical scattering mechanisms such as focused specular reflections resist thickness interference effects reflections from substrate grains and focusing of incident light by the resist curvature. Specular reflection from topography can focus incident radiation causing a 10-fold increase in effective exposure. Further complications such as dimples in the surface of positive resist features can result from a second reflection of focused energy by the resist/air interface. Variations in line-edge exposure due to substrate grain structure are primarily specular in nature and can become significant for grains larger than )tresi Local exposure variations due to vertical standing waves and changes in energy coupling due to changes in resist thickness are displaced laterally and are significant effects even though they are slightly less severe than vertical wave propagation theory suggests. Focusing effects due to refraction by the curved surface of the resist produce only minor changes in exposure. Increased resist contrast and resist absorption offer some improvement in reducing notching effects though minimizing substrate reflectivity is more effective. CPU time using 32 virtual nodes to simulate a 4 pm by 2 pm isolated domain with 13 bleaching steps was 30 minutes

Paper Details

Date Published: 1 June 1990
PDF: 11 pages
Proc. SPIE 1264, Optical/Laser Microlithography III, (1 June 1990); doi: 10.1117/12.20197
Show Author Affiliations
Karim H. Tadros, Univ. of California/Berkeley (United States)
Andrew R. Neureuther, Univ. of California/Berkeley (United States)
John Kenneth Gamelin, Univ. of California/Berkeley (United States)
Roberto Guerrieri, Univ. di Bologna (United States)

Published in SPIE Proceedings Vol. 1264:
Optical/Laser Microlithography III
Victor Pol, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?