大口径φ３００ｍｍＳｉウエハ用超加工機械の開発

Abstract

According to the roadmap of the semiconductor industry, the current Φ200mm (8) silicon wafer will be replaced by Φ300mm (12) by the year 2003. The present manufacturing process for silicon wafer includes lapping, etching and polishing. Such free slurry methods can achieve better surface roughness only when smaller abrasives are applied, therefore, require multi-stage equipments and are energy consuming. In addition to the low throughput, the current pressure-controlled process is also unable to fulfil the requirement on global flatness as the wafer size increases. To address the problems of throughput rate, post-process cleaning, environmental impact as well as to achieve the total surface integrity for Φ300mm silicon wafer, the semiconductor industry was looking for a fixed abrasive solution as the alternative. This research has developed a one-stop manufacturing system for Φ300mm silicon wafer, using fixed abrasive instead of conventional free slurry, to provide a totally integrated solution for achieving the surface roughness Ra<1nm (Ry<5-6nm) and the global flatness<0.2μm/Φ300mm. In addition to the space saving, this one-stop system also significantly reduces the total energy consumption, compared with the current process used for Φ200mm Si wafer. Three core technologies: the hybrid process mechanics, the GMM actuated positioning/alignment device and the ecologically friendly coolant circulation system are described in this paper. The system performance and results are then presented and discussed.