Thick Film Photo Resist Spun on Application vs. Dry Film Lamination

摘要

As the success and functionality of smart phones continues to grow around the world, miniaturization of electronic components remains one of the main trends in mobile communications. Wafer Level Packaging (WLP) continues to be a significant area of interest for RF front end module makers such as TriQuint. The possibilities to shrink die sizes and simplify the packaging process can amount to a significant cost saving. This can be of strategic importance in a market where price competition is fierce. WLP processes are evolving, from flip chip capability to 3 dimensional cavity formations at the wafer level. Many of these processes require thick film photo resists and epoxies as part of the process flow. The standard photolithography process, where photo resist is spun onto the wafer, has made strides to accommodate this trend. However, in this process development space dry film photo resists are emerging as an attractive alternative This paper will discuss the development of an electroplating process. The author will compare a spin on photolithography solution with a dry film photolithography solution. The paper will compare process flows, process development challenges, capacity and cost comparison for each approach.