Ashing Process on Warpage Wafer with Low Damage

To improve the surface quality of polyimide (PI) or photoresist (PR) ashing/striping on warpage wafer, the issues of arcing, peeling and damage should be overcome. In this work, we demonstrate a time-multiplexed alternating ashing (TMAA) process for 12-inch warpage wafer. The TMAA process can reduce the risk of arcing and peeling with higher uniformity. Therefore, the TMAA process is a low cost and highly efficient method for the surface treatment in advanced packaging.