,Photocurrent Property of GaN on the Si Photodetector with a Nearly Polycrystalline α-Al2O3 Buffer L

• 作 者: 江若琏 王军转 陈鹏 赵作明 梅永丰 沈波 张荣 吴兴龙 郑有料
• 机 构: Department of Physics, Nanjing University, Nanjing 210093
• 出 处: 中国物理快报（英文版）
• 发表日期: 2002年10期

Using nearly polycrystalline α-Al2O3 as the buffer layer, GaN epilayers were grown on Si(111) substrates by low-pressure metal-oragnic chemical vapour deposition. The nearly polycrystalline α-Al2O3 was formed by anodicporous alumina annealed at high temperature. Prototype photoconductive detectors were fabricated with thesematerials. The spectral response of these detectors exhibits a relatively sharp cut-off near the wavelength of360nm and a peak at 340nm with a shoulder near 360nm. Under 5 V bias, the responsivities at 340nm and360nm were measured to be 3.3 A/W and 2.4A/W, respectively. The relationship between the responsivity andthe bias voltage shows that the responsivity is saturated when the bias voltage reaches 5 V.