Requirements for wafer level packaging materials

Summary form only given. Innovations in microelectronic device fabrication, specifically new advanced electronic packaging schemes, continue to require evolution and commercial implementation of new polymeric materials in many “far back end of the line” (FBEOL) stress buffer and RDL applications. Changing design architectures, as well as implementation of new inorganic dielectric layers, continue to drive improved device performance, but generally at the sacrifice of high, unwanted physical stress. We will highlight how the physical properties of photosensitive polyimides (PI) and photosensitive poly(benzoxazoles) (PBO) compare with new “low stress” formulations currently under development.