Characterization of Negative Photoresist Processing by Statistical Design of Experiment (DOE)

  • Mun Sei-Young (Department of Electronic Engineering at Myongji University) ;
  • Kim Gwang-Beom (Department of Electronic Engineering at Myongji University) ;
  • Soh Dea-Wha (Department of Electronic Engineering and director of semiconductor technology center at Myongji University) ;
  • Hong Sang Jeen (Department of Electronic Engineering & NBRC at Myongji University)
  • Published : 2005.12.01

Abstract

SU-8 is a epoxy based photoresist designed for MEMS applications, where a thick, chemically and thermally stable image are desired. However SU-8 has proven to be very sensitive to variation in processing variables and hence difficult to use in the fabrication of useful structures. In this paper, negative SU-8 photoresist processed has been characterized in terms of delamination, based on a full factorial designed experiment. Employing the design of experiment (DOE), a process parameter is established, and analyzing of full factorial design is generated to investigate degree of delamination associated with three process parameters: post exposure bake (PEB) temperature, PEB time, and exposure energy. These results identify acceptable ranges of the three process variables to avoid delamination of SU-8 film, which in turn might lead to potential defects in MEMS device fabrication.

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