Makoto Inagawa

Real-time substrate misalignment monitor and automatic recalibration

Real-time substrate misalignment monitoring and automatic position recalibration were demonstrated in the Applied Komatsu Technology physical vapor deposition cluster tool. To accomplish this, two techniques were used to detect substrate misalignment and determine the source of the error. The cluster tool consists of an atmospheric cassette load station, a load lock station, a transfer chamber, a preheat chamber and four process chambers. Accelerometers were installed at each module of the cluster tool to detect any unexpected vibration of the substrate as it is lowered into processing position. The substrate misalignment is monitored at the atmospheric cassette load station with a ±0.5 mm threshold value using an optical sensor. If excessive substrate misalignment is detected at the atmospheric cassette load station, the accelerometer data is used to determine which specific module of the cluster tool was operating improperly. Using the monitored misalignment value at the atmospheric cassette load statio...