1. Technology Division, SUMCO Corporation1‐52 Kubara, Yamashiro‐cho, ImariSaga 849‐4256Japan
2. Customer Product Engineering Department, Technology Division, SUMCO Corporation2201 Oaza Kamioda, Kohoku‐machi, Kishima‐gunSaga 849‐0597Japan
3. Advanced Evaluation and Technology Department, Technology Division, SUMCO Corporation1‐52 Kubara, Yamashiro‐cho, ImariSaga 849‐4256Japan