Adhesive Solutions for Closed Cavity Packaging

Abstract

The trend towards autonomous driving demands continuously increasing safety requirements and hence reliable components such as CMOS image sensors or communication devices. To provide such components, manufactures are facing ever greater challenges as the sensor packages need to be airtight-sealed over its whole lifetime. Typical defects that can be observed when using conventional lid attach materials for closed cavity packages in tests at automotive level (e.g., according to AEC Q100) are pop-up effects and delamination. To avoid these defects and to meet the increasing reliability requirements of the semiconductor industry, DELO Industrial Adhesives has developed special adhesives that not only ensure reliable bonding while keeping narrow and high bondlines, but also improve process stability. The required adhesive properties were defined by an FE analysis model. To test suitability of the new developments, dummy image sensor packages were built up, which passed through the testing of the bearing, according to AEC Q 100 standard. Finally, the tightness of the bondline was checked via microscope and other methods. Features such as light/heat B-stage or light fixation help to keep the attached lid in place during heat curing and other subsequent steps like temperature cycling, humidity storage or reflow.