Control methods of semiconductor manufacturing process, semiconductor manufacturing equipment, and semiconductor manufacturing environment

摘要

A control method of semiconductor manufacturing equipment allows early detection of deterioration in the equipment. After cleaning the upper surface of an SOI layer (3), a silicon oxide film (4) is formed thereon by thermal oxidation. At this time, deterioration of a cleaning bath or an oxidation furnace causes the mixing of impurities (5) into a monitor wafer (50). Since the SOI wafer (3) has little gettering capabilities and the monitor wafer (50) has no impurity trap region, most of those impurities (5) are stored in the silicon oxide film (4), etc. The stored impurities (5) cause anomalies in the thickness or quality of the silicon oxide film (4), so that the evaluated characteristics of the silicon oxide film (4) vary from the normal. Accordingly, deterioration in the semiconductor manufacturing equipment can be judged when the characteristics of the silicon oxide film (4) vary from the normal.