Resist Mechanisms and Models in Electron-Beam Lithography
Nelson N.-S. Tam
EECS Department
University of California, Berkeley
Technical Report No. UCB/ERL M91/102
1991
http://www.eecs.berkeley.edu/Pubs/TechRpts/1991/ERL-91-102.pdf
An in-depth examination of chemical and physical mechanisms in resist materials has been made to support the applications of electron-beam (e-beam) lithography with high beam current exposure systems and advanced resist systems. Novel resist models and extensions to the lithography simulator SAMPLE have been developed to provide a CAD capability for inexpensive and rapid evaluation of new e-beam lithographic processes. Due to the small thermal conductivity of resists, e-beam induced heating of resists during exposure can be quite significant. Resist deformation and irregular dissolution behaviors have been observed in the RD-2000N resist when the beam current density exceeds 25 A/cm2. A massively parallel computer program using an explicit Euler algorithm has been developed to simulate the temperature rise in the resist during exposure as a function of pattern, tool and resist parameters. A novel approach of using empirically-modeled parameters in the mechanism-based rate model is introduced to include additional process variables. An application to developer concentration and post-exposure bake (PEB) makes possible profile simulation for the optimization of these processing steps in chemically-amplified resists.
Advisor: Andrew R. Neureuther
BibTeX citation:
@phdthesis{Tam:M91/102,
Author = {Tam, Nelson N.-S.},
Title = {Resist Mechanisms and Models in Electron-Beam Lithography},
School = {EECS Department, University of California, Berkeley},
Year = {1991},
URL = {http://www.eecs.berkeley.edu/Pubs/TechRpts/1991/1878.html},
Number = {UCB/ERL M91/102},
Abstract = {An in-depth examination of chemical and physical mechanisms in resist
materials has been made to support the applications of electron-beam
(e-beam) lithography with high beam current exposure systems and
advanced resist systems. Novel resist models and extensions to
the lithography simulator SAMPLE have been developed to provide a
CAD capability for inexpensive and rapid evaluation of new e-beam
lithographic processes.
Due to the small thermal conductivity of resists, e-beam induced
heating of resists during exposure can be quite significant. Resist
deformation and irregular dissolution behaviors have been observed in
the RD-2000N resist when the beam current density exceeds 25 A/cm2. A
massively parallel computer program using an explicit Euler algorithm
has been developed to simulate the temperature rise in the resist
during exposure as a function of pattern, tool and resist parameters.
A novel approach of using empirically-modeled parameters in the
mechanism-based rate model is introduced to include additional
process variables. An application to developer concentration and
post-exposure bake (PEB) makes possible profile simulation for the
optimization of these processing steps in chemically-amplified
resists.}
}
EndNote citation:
%0 Thesis %A Tam, Nelson N.-S. %T Resist Mechanisms and Models in Electron-Beam Lithography %I EECS Department, University of California, Berkeley %D 1991 %@ UCB/ERL M91/102 %U http://www.eecs.berkeley.edu/Pubs/TechRpts/1991/1878.html %F Tam:M91/102