高响应度GaN紫外探测器

High Responsivity GaN Ultraviolet Photodetector

采用MOCVD方法,在蓝宝石衬底上以低温GaN为缓冲层生长了GaN外延层。以上述材料制备了金属-半导体-金属(M-S-M)光导型GaN探测器。该探测器的光谱响应表明:器件在330～360nm内有高的灵敏度,并且在360nm附近有陡峭的截止边,对可见光和近红外光几乎没有响应,在5V偏压下358nm处峰值响应度高达1200A/W。研究了光从探测器的正、背面入射时对响应度的影响,并讨论了其原因。

GaN epilayers were grown on sapphire substrates by metal-organic chemical vapor deposition, with low-temperature GaN as the buffer layer. Metal-semiconductor-metal photoconductive detectors were fabricated using this material. The spectrum response shows a high sensitivity at a wavelength from 330 to 360 nm, with a sharp cutoff at the wavelength of near 360 nm, which means there is no response in the visible and infrared region. The maximum responsivity is 1 200 A/W at 358 nm under 5 V bias. The effect of f...