Wafer Level Packaging Materials
A coordinated activity within the Materials/Wafer Fabricators/OEMs supply chain to quickly and thoroughly evaluate new material options. Increasing pace of new materials introduction by multiple suppliers can overwhelm design, packaging, and testing resources –if everything is evaluated. By the time a material (i.e., mold compound, repassivation, coating, doped solder, etc.) is qualified, newer “improved’ materials are offered. An effort like this is needed to quickly determine the best alternatives, and significantly reduce the cost and effort by the suppliers, by focusing on the specific needs of the OEMs and ODMs. When we are finished, the users will be ready to implement the alternatives, because they have been part of the development.
The length of time for a new wafer material to be qualified takes longer then it does to create a BOM for a new package. The increasing pace of new materials introduced by multiple suppliers can overwhelm design, packaging, and testing resources. By the time a material (i.e., mold compound, repassivation, coating, doped solder, etc.) is qualified, newer “improved” materials are offered.
More efficient and cost-effective methodology for evaluating new materials and/or packaging reliability is required. This would create shorter development times allowing faster package time-to-market.
Assemble a team of material suppliers, OSAT’s, WLCSP forum members, and IC suppliers. The team would design a test vehicle that would consist of High pin count (> 12x12 array). Next they would do a base line and materials/ process evaluation consisting of Doped solders, repassivation, stress coating, underfill, pillar vs. bumps, etc. Finally testing using; flex, thermal cycling, and EM standard tests would be preformed. As a result of the data collection and analysis the team would define rules for standard material evaluation projects. Finally, one or more material evaluations would be preformed to test the rules.