Low Temperature Adhesive Die Bonding for Sensitive MEMS Dies

Since it is necessary to understand the reliability of die-substrate bonds, this paper investigates the shear forces of these bonds for some selected die-attach adhesives for different substrates and die sizes.The investigation can be divided into 3 phases, (a) the study, selection and procurement of commercial adhesives satisfying certain requirements (low-stress, MEMS compatibility, specific die-attach substrates, and dispensing capability) and low outgassing standards (NASA ASTM E595 or MIL-STD 883/5011), (b) Dispensing and pick-and-place experiments, and (c) die shear testing. The Dispenser D-X30 dispenses the adhesive on the substrate and the placer module (Häcker Automation) picks and places the mapped dies on them. After the dies are cured at room temperature, the die-substrate bonds are tested by shearing the dies off the substrate to measure the shear test forces. For this purpose, the existing Zwicki Z2.5kN load tool is designed in a way to meet the die shear testing standards (MIL-STD-883) to duplicate a standard shear tester. The results are also verified against a standard shear test tool. Finally, the force results are evaluated to understand the reliability of the selected die attach adhesives.