Publisher : The Korean Microelectronics and Packaging Society
DOI : 10.6117/kmeps.2015.22.3.057
Title & Authors
Sensitivity Enhancement of Shadow Moiré Technique for Warpage Measurement of Electronic Packages Lee, Dong-Sun; Joo, Jin-Won;
Electronic packages consist of various materials, and as temperature changes, warpage occurs because of the difference in coefficient of thermal expansion. Shadow is non-contact, whole field measurement technique for out-of-plane displacement. However, the technique has low sensitivity above , it is not adequate for the warpage measurement in some circumstance. In this paper, by applying phase shifting process to the traditional shadow , measurement system having enhanced sensitivity of is constructed. Considering Talbot effect, the measurement is carried out in the half Talbot area. Shadow fringe pattern having four times enhanced sensitivity is obtained by the image process with four shadow fringes. The measurement technique is applied to the fibered package substrate and coreless package substrate for measuring warpages at room temperature and at about .
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