Comparison of scalar and vector diffraction modelling for deep-UV lithography

Show full item record

Title: Comparison of scalar and vector diffraction modelling for deep-UV lithography
Author: Smith, Bruce; Flagello, Donis; Summa, Joseph; Fuller, Lynn
Abstract: As deep-UV projection system complexity increases to pursue 0.25 micron resolution, the adequacy of diffraction theory using scalar models is of concern. Approximations that are suitable for low NA reduction systems do not hold true for higher NAs. Furthermore, scalar models treat all illumination as polarized perpendicular to the plane of incidence. Feature interaction effects from the polarized radiation of an excimer laser both in a projection system and within a photoresist film cannot be accounted for. Vector diffraction theory has been utilized more appropriately for modelling in these situations, but deviations of scalar predictions from those made with vector models do not warrant abandonment. This paper will describe investigations into scalar and vector diffraction modelling for 248 nm lithography. An experimental design approach was used to study the effects and interactions of coherence, polarization, and numerical aperture on a resist feature response. An exposure latitude response to achieve 1 0% linewidth control with +1- 0.3 micron of defocus was utilized. Both vector and scalar diffraction models were used to simulate process runs. Experimental comparisons were made using a variable NA, variable coherence deep-UV projection system, adapted for control of polarization at the aperture of the mask. Exposure latitude response surfaces are presented, along with details on isolated process runs.
Record URI: http://hdl.handle.net/1850/11390
Date: 1993-04

Files in this item

Files Size Format View
BSmithConfProc04-1993.pdf 455.9Kb PDF View/Open

The following license files are associated with this item:

This item appears in the following Collection(s)

Show full item record

Search RIT DML


Advanced Search

Browse