초박형 실리콘 웨이퍼 연삭에서 두께 및 Feed Rate에 따른 표면 손상 특성 분석

Abstract

This study investigates the effects of wafer thickness and feed rate on surface damage characteristics in ultra-thin silicon wafer grinding processes. Silicon wafers of two thicknesses (100 µm and 500 µm) were ground under identical conditions to compare the resulting surface damage, including scratches, cracks, and chipping. The grinding experiments revealed significant differences in surface integrity across wafer thicknesses. Ultra-thin wafers (100 µm) exhibited severe surface defects due to reduced mechanical stiffness and increased susceptibility to local stress concentrations. Conversely, thicker wafers (500 µm) exhibited markedly improved surface quality, with min imal defects, due to their higher stiffness and more uniform distribution of contact pressure during grinding. Addi tionally, varying the feed rate (1, 3, and 5 µm/s) during grinding at a wafer thickness of 500 µm indicated that higher feed rates improved surface finish and flatness by reducing mechanical stresses. Finite Element Analysis (FEA) sim ulations using ABAQUS supported these experimental findings, demonstrating that higher feed rates led to more stable contact conditions, thereby significantly reducing localized stress concentrations and surface damage. These results suggest that optimal grinding conditions—500 µm wafer thickness combined with a feed rate of 5 µm/s— minimize surface damage and enhance productivity in ultra-thin wafer manufacturing.