Focusing on the demolding issues of high aspect ratio structures, this paper attempts to explain the reasons behind this problem. Firstly, the material properties of the cured resist was measured, and Ogden model was used to describe its behavior. Then, a roll to roll UV curing and demolding numerical model was constructed and analyzed. It was found that the adhesive forces between mold and structures is the major cause of maximum stress in cured resist when aspect ratio is set to 4∶1. Moreover, a longer curing time, a thinner residual layer thickness, a smaller structure aspect ratio and a bigger structure gap can lead to smaller maximum stress during the curing and demolding process.
WU Hao,YI Peiyun,PENG Linfa,LAI Xinmin
. Numerical Analysis of the UV Curing and Demolding Process for
High Aspect Ratio Micro Structure[J]. Journal of Shanghai Jiaotong University, 2018
, 52(12)
: 1603
-1608
.
DOI: 10.16183/j.cnki.jsjtu.2018.12.009
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