The Effect of Heavy Fe-Doping on 3D Growth Mode and Fe Diffusion in GaN for High Power HEMT Application

Materials

Thi Thu Mai¹  Wu-Ching Chou¹  Shao-Chien Chang¹  Cheng-Wei Liu¹  Hsin-I Hsiao¹  Jin-Ji Dai¹  Ssu-Kuan Wu¹  Hua-Chiang Wen¹  Umeshwar Reddy Nallasani¹  Luc Huy Hoang²  Chieh-Piao Wang³ 

[1] Department of Electrophysics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan;Faculty of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi 10000, Vietnam;Technology Development Division, Episil-Precision Inc., Hsinchu 30010, Taiwan;

关键词: GaN power HEMT;    MOCVD;    Fe doping;    nano-mask;    3D growth;    diffusion;   

DOI  :  10.3390/ma15062058

来源: DOAJ

【 摘 要 】

The high electron mobility transistor (HEMT) structures on Si (111) substrates were fabricated with heavily Fe-doped GaN buffer layers by metalorganic chemical vapor deposition (MOCVD). The heavy Fe concentrations employed for the purpose of highly insulating buffer resulted in Fe segregation and 3D island growth, which played the role of a nano-mask. The in situ reflectance measurements revealed a transition from 2D to 3D growth mode during the growth of a heavily Fe-doped GaN:Fe layer. The 3D growth mode of Fe nano-mask can effectively annihilate edge-type threading dislocations and improve transfer properties in the channel layer, and consequently decrease the vertical leakage current by one order of magnitude for the applied voltage of 1000 V. Moreover, the employment of GaN:C film on GaN:Fe buffer can further reduce the buffer leakage-current and effectively suppress Fe diffusion.

【 授权许可】

Unknown