Dry developable lithography as represented by the DESIRE process, is one of the most attractive surface imaging technologies for advanced optical lithography. A resolution of 0.25 micrometers has been demonstrated with this process, using i-line exposure in conjunction with a phase shifting mask and by deep-UV exposure (248 nm). Surface imaging is especially suited for deep-UV lithography since it overcomes the poor CD-control over topography encountered with highly transparent wet developable resists. In this work the applicability of DESIRE to sub-0.5 micrometers processing has been studied. With regard to the silylation process, crosslinking effects resulting from the radiation at 248 nm have been found to reduce the Si incorporation. This crosslinking effect can be reduced by the use of alternative silylating agents (such as TMDS 1,1,3,3-tetramethyl disilazane), which silylate at a lower temperature. A comparison of processing latitudes for lines and for contact holes has been made for silylation with HMDS and with TMDS. Other issues related to the implementation of DESIRE in typical CMOS processing, such as dry etch compatibility and resist stripping have also been addressed.

Date Published: 1 June 1991
PDF: 12 pages
Proc. SPIE 1466, Advances in Resist Technology and Processing VIII, (1 June 1991); doi: 10.1117/12.46408

Published in SPIE Proceedings Vol. 1466:
Advances in Resist Technology and Processing VIII
Hiroshi Ito, Editor(s)