[3] [3] HE Y L, HE Q, MI M H, et al. Fully recessed-gate normally-off AlGaN/GaN high electron mobility transistors with high breakdown electric field ［C］ // 1st WiPDA Asia. Xi'an, China. 2018: 203-207.

[4] [4] DONG N, LIU M, SHI L, et al. A normally-off P-Gate AlGaN/GaN HEMT for high power application ［C］ // IEEE Int Conf EDSSC. Shenzhen, China. 2018: 1-2.

[5] [5] RAJABI S, OROUJI A A, MOGHADAM H A, et al. A novel AlGaN/GaN/AlGaN double-heterojunction high electron mobility transistor for performance improvement ［C］ // IEEE ICSCCN. Thuckafay, India. 2011: 675-678.

[6] [6] SAITO W, TAKADA Y, KURAGUCHI M, et al. Recessed-gate structure approach toward normally off high-voltage AlGaN/GaN HEMT for power electronics applications ［J］. IEEE Trans Elec Dev, 2006, 53(2): 356-362.

[8] [8] MA J, ZHANG J, XUE J, et al. Overcoming the poor crystal quality and DC characteristics of AlGaN/ GaN/AlGaN double-heterostructure high electron mobility transistors ［J］. Physica Status Solidi A-Appl & Mater Sci, 2016, 213(8): 2203-2207.

[10] [10] AMBACHER O, MAJEWSKI J, MISKYS C, et al. Pyroelectric properties of Al(In)GaN/GaN hetero-and quantum well structures ［J］. J Phys Conden Matt, 2002, 14(13): 3399-3434.