3.4 Existing Simulators and Future Perspectives

The availability of simulation tools with extended physical models, rapid algorithms, design options, and convenient user interfaces is improving rapidly. There are mainly two types of sites developing and providing simulators:

• Universities and research institutes offer the most advanced physical models. Especially three-dimensional tools are primarily developed there. Usually they provide the source code making the programs suitable for incorporation of user supplied physical models.
• Commercial vendors generally emphasize user-friendly and task-oriented interfaces including turnkey operation. Most of the commercial tools are originally based on university codes with an additional graphical user interface.

Table 3.1 summarizes some well-known simulators in alphabetical order. Most of the functionality assisting the practical characterization as described in Section 3.2 is implemented in the commercial tools and with a smaller extent also in university codes. Advanced models needed for the simulation of technology innovations (cf. Section 3.3), however, are barely available from commercial vendors. Here lies the strength of universities in developing extended physical simulators since they rather have the possibility to perform basic research and can also directly cooperate with semiconductor manufacturers. In this thesis the emerging problem of a rigorous electromagnetic treatment of topography effects is investigated and a new three-dimensional simulation model is developed.

 

Table 3.1: Summary of lithography simulators (after [101, p. 667]).

 

Program	Organization	Developers
DEPICT	Technology Modeling Associates, Palo Alto, CA http://www.tmai.com/PRODUCT/depict.html	D.A. Bernard [102,103]
FAIME	Vector Technologies, Bethesda, MD	E. Barouch [104,65]
METROPOLE	Carnegie Mellon University, Pittsburgh, PA	A.J. Strojwas [105,10]
OPTOLITH	Silvaco International, Sunnyvale, CA http://www.silvaco.com/products/athena/optolith/optolith.html	W. Henke [106]
PROLITH	FINLE Technology, Austin, TX http://www.finle.com/Prolith/software.html	C.A. Mack [107,108]
SAMPLE	University of California, Berkeley, CA http://tanqueray.eecs.berkeley.edu/tcad/tcad.html	A.R. Neureuther [109,110]
SOLID-C	Sigma-C, Munich, Germany http://www.sigma-c.de/solid-c/default.html	W. Henke [106]

The simulators METROPOLE and SAMPLE are both university codes. In the developer column just the responsible Professor is noted, although most of the work was done by Ph.D. students.

The simulators OPTOLITH and SOLID-C are both based on the code SOLID that was originally developed at the Fraunhofer Institut für Siliziumtechnologie, Itzehoe, Germany (http://www.isit.fhg.de/english/simulation/solid.html).