J4 ›› 2011, Vol. 28 ›› Issue (6): 737-741.

• Semiconductor Opto-electronics • Previous Articles     Next Articles

Photoelectric properties of 4H-SiC UV photodetector at various temperatures

ZHENG Yun-zhe1,2, LIN BING-jin1, ZHANG Ming-kun1,3, CAI Jia-fa1,2, Chen Xia-pin1,2, WU Zheng-yun1,3   

  1. 1 Department of Physics,  Xiamen University, Xiamen 361005, China;
    2 Fujian Key Laboratory of Semiconductor Materials and Application, Xiamen 361005, China;
    3 Pen-Tung Sah Micro-Nano Technology Research Center, Xiamen University,  Xiamen 361005, China
  • Received:2010-12-14 Revised:2011-03-15 Published:2011-11-28 Online:2011-11-14

Abstract:

The dark current and relative spectral response of 4H–SiC ultraviolet p-i-n photodetector had been investigated with the temperature decreasing from 300 K to 60 K by photocurrent measurement. It is found that the dark current and relative spectral response of the device declined during the whole period and that the higher the reverse bias voltage is, the faster the falling rate of dark current are. At the reverse bias of 0V, when the temperature dropped, the peak response wavelength of the device firstly shifted slowly to the short wavelength direction and then moved to the opposite direction, reaching around 282 nm at 60 K. Meanwhile, a littie narrowing of relative spectral response of the device was observed. Furthermore, the mechanism of influences of temperature on photocurrent produced in p, i, n layers had been investigated, and proposal that lessening defect in i layer and reducing properly doping concentration in n layer were proposed to enhance the relative spectral response of the device.

Key words: optoelectronics, 4H-SiC, p-i-n UV photodetector, temperature dependence, photoelectric properties

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