[1] Natl Sun Yat Sen Univ, Dept Mat & Optoelect Sci, Kaohsiung 804, Taiwan
[2] Peking Univ, Sch Software & Microelect, Beijing 100871, Peoples R China
[3] Natl Sun Yat Sen Univ, Dept Phys, Kaohsiung 804, Taiwan
[4] Natl Cheng Kung Univ, Adv Optoelect Technol Ctr, Tainan 700, Taiwan
[5] Tung Fang Design Univ, Dept Elect Engn & Comp Sci, Kaohsiung, Taiwan
[6] Natl Kaohsiung Normal Univ, Dept Chem, Kaohsiung, Taiwan
[7] Natl Sun Yat Sen Univ, Dept Mech & Electromech Engn, Kaohsiung 80424, Taiwan
[8] Xidian Univ, Sch Tech Phys, Xian, Shanxi, Peoples R China
[9] Natl Chiao Tung Univ, Dept Elect Engn, Hsinchu 300, Taiwan