Chinese Optics Letters, 2011, 9 (1): 010401, Published Online: Jan. 7, 2011
Transmission-mode GaN photocathode based on graded AlxGa1 xN buffer layer
紫外探测器 GaN 光电阴极 缓冲层 界面复合速率 光电发射 040.7190 Ultraviolet 160.1890 Detector materials 230.0040 Detectors 260.7210 Ultraviolet, vacuum
Abstract
We create a GaN photocathode based on graded AlxGa1?xN buffer layers to overcome the influence of buffer-emission layer interface on the photoemission of transmission-mode GaN photocathodes. A gate-shaped spectral response with a 260-nm starting wavelength and a 375-nm cut-off wavelength is obtained. Average quantum efficiency is 15% and short wavelength responses are almost equivalent to long wavelength ones. The fitted interface recombination velocity is 5×104 cm/s, with negligible magnitude, proving that the design of the graded buffer layers is efficient in obtaining good interface quality between the buffer and the emission layer.
Xiaoqing Du, Benkang Chang, Yunsheng Qian, Pin Gao. Transmission-mode GaN photocathode based on graded AlxGa1 xN buffer layer[J]. Chinese Optics Letters, 2011, 9(1): 010401.