[1] Natl Cheng Kung Univ, Inst Microelect, Tainan 70101, Taiwan
[2] Natl Cheng Kung Univ, Dept Elect Engn, Tainan 70101, Taiwan
[3] Cheng Shiu Inst Technol, Dept Elect Engn, Kaohsiung 830, Taiwan
[4] Natl Cent Univ, Dept Phys, Chungli 320, Taiwan
[5] S Epitaxy Corp, Hsin Shi 744, Taiwan
[6] Nan Jeon Jr Coll Technol & Commerce, Dept Elect Engn, Yenshui 737, Taiwan
[7] Natl Yunlin Univ Sci & Technol, Dept Elect Engn, Touliu 640, Taiwan