DRIE, an Enabling Technology for High Density Packaging

Abstract

Efficient plasma processing equipment that has made possible the cost effective precision etching of MEMS devices, is equally capable of providing very high etch rates and excellent etch uniformity when applied to device packaging requirements. Deep Reactive Ion Etching (DRIE) can be used to etch interconnect vias prior to metallization for System-in-Package (SiP) applications. One such technology focuses on fabricating 3D stacks of chips in a single package. Alternatively, the requirement may be for the etching of scribe channels and the exposure of contacts to devices as an intermediate stage in a Chip Scale Packaging (CSP) process. Many MEMS devices are still etched on 150 mm wafers, while most IC devices requiring CSP or other processing relating to Advanced Packaging will be manufactured on 200 mm wafers with planned moves to 300 mm wafers in progress or imminent. For these requirements it becomes increasingly important to design plasma processing equipment that is capable of achieving very high etch uniformity over the larger wafer sizes and high etch rate to reduce the cost of ownership. Experimental results of direct application to device packaging are presented for wafer sizes up to and including 300 mm, demonstrating the capabilities of the latest technical developments.