Wafer Thinning Process and Its Critical Manufacturability Requirements
Bryan Christian S. Bacquian *
STMicroelectronics, Inc., Calamba City, Laguna, 4027, Philippines.
*Author to whom correspondence should be addressed.
Abstract
Wafer Thinning as a major semiconductor process steps to attain miniaturization of Integrated Circuit or IC. Wafer back grinding up to 70 µm thickness is considered critical due to its fragility. The paper will discuss the definition and establishment of critical equipment check items to lessen the risk of breakage. Equipment covered was an inline wafer back grinding and wafer mounting. The research has used a qualitative approach by applying process mapping to identify critical sub-process steps. Thereafter, the results show the establishment of critical equipment subprocess steps such as grinding, lamination and de taping. Foreign material and alignment control are considered areas for improvement and have incorporated the control at the equipment preventive maintenance. After all the evaluation, wafer thinning process was successfully released and proliferated from development to manufacturing.
Keywords: Wafer, wafer thinning, back grind tape, chuck table condition, polishing pad.