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http://dx.doi.org/10.5762/KAIS.2014.15.11.6464

Analysis of the shrinkage and warpage of Wafer lens during UV curing  

Park, Sihwan (School of Mechanical Engineering, Ulsan College)
Moon, Jong-Sin (LG Electronics)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.15, no.11, 2014 , pp. 6464-6471 More about this Journal
Abstract
The UV curing method is a popular process for lens molding on a unit wafer. This process, however, has several drawbacks including wafer adhesion during the ejection process after curing, errors in lens shape and wafer warpage due to material shrinkage during the curing process, and lens centering errors on both sides of a wafer. Among these, the lens shape error and warpage are influenced directly by the UV curing process due to factors including the UV radiation uniformity, the degree of cure according to UV intensity, and the shrinkage characteristics of the material. Therefore, a theory is needed not only to understand the change in the material characteristics, such as the shrinkage rate due to the curing reaction, but also to establish a model. In addition, an analysis system is needed to realize the model. This study proposes a new analysis method for the wafer lens molding process by Comsol modeling. This method was verified by comparing the results with those of the actual process.
Keywords
Curing Model; UV Curing; Wafer level lens; Warpage;
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