Investigation on Internal Stress of SU-8 Photoresist Film

Abstract:

In this paper, substrate curvature method was adopted and a theory model based on Stoneys formula was built for obtaining the internal stress of SU-8 film. The effect of substrate diameter, film thickness and post-baked temperature on substrate curvature ratio was investigated by ANSYS simulation. The analytical result shows that post-baked temperature is the main effect factor on internal stress of SU-8 film. In addition, internal stresses of SU-8 at three different post-temperatures (55°C, 70°C and 85°C) are measured. The results show that the experimental results greatly agreed with simulation analytical results. It means the internal stress of SU-8 film can be accurately described by the theory model, which provides a basis for the quantitative analysis of the internal stress in SU-8 film.

• Periodical: Key Engineering Materials (Volume 613)
• Pages: 251-258
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.613.251
• Online since: May 2014
• Authors: Xiao Lei Zhang, Li Qun Du*, Shen Miao Zhu
• Keywords: ANSYS Simulation, Internal Stress, Stoneys Formula, SU-8 Photoresist, Substrate Curvature Method

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