[1] Hebei Univ Technol, Sch Elect Informat Engn, Tianjin 300130, Peoples R China
[2] Hebei Univ Technol, Tianjin Key Lab Elect Mat & Devices, Tianjin 300130, Peoples R China
[3] Hebei Collaborat Innovat Ctr Microelect Mat & Tech, Tianjin 300130, Peoples R China
[4] Hebei Engn Res Ctr Microelect Mat & Devices ERC, Tianjin 300130, Peoples R China