摘要
We study the performance of GaN-based p i n ultraviolet （UV） photodetectors （PDs） with a 60 nm thin ptype contact layer grown on patterned sapphire substrate （PSS）. The PDs on PSS exhibit a low dark current of -2 pA under a bias of -5 V, a large UV/visible rejection ratio of-7× 10^3, and a high-quantum efficiency of -40% at 365 nm under zero bias. The average quantum efficiency of the PDs still remains above 20% in the deep-UV region from 280 to 360 nm. In addition, the noise characteristics of the PDs are also discussed, and the corresponding specific detectivities limited by the thermal noise and the low-frequency 1/f noise are calculated.
We study the performance of GaN-based p i n ultraviolet （UV） photodetectors （PDs） with a 60 nm thin ptype contact layer grown on patterned sapphire substrate （PSS）. The PDs on PSS exhibit a low dark current of -2 pA under a bias of -5 V, a large UV/visible rejection ratio of-7× 10^3, and a high-quantum efficiency of -40% at 365 nm under zero bias. The average quantum efficiency of the PDs still remains above 20% in the deep-UV region from 280 to 360 nm. In addition, the noise characteristics of the PDs are also discussed, and the corresponding specific detectivities limited by the thermal noise and the low-frequency 1/f noise are calculated.
基金
supported by the China Postdoctoral Science Foundation Funded Project(No.2013M540437)
the Natural Science Foundation of Jiangsu Province(No.BK2012110)
the Joint Innovation Project of Jiangsu Province(No.BY2013015-19)
the Fundamental Research Funds for the Central Universities of China(Nos.JUSRP51323B and JUDCF13038)
