摘要
针对具备100~200nm薄吸收区的肖特基型探测器,研究了不同金属接触对其暗电流和光谱响应特性的影响。以GaN基材料为主体,在薄层Al_(0.42)Ga_(0.58)N表面分别制备Au和Ni/Au形成肖特基接触,在Al_(0.55)Ga_(0.45)N表面以Ti/Al/Ti/Au制备欧姆接触,从而制备薄吸收区的AlGaN肖特基日盲探测器。结果表明对AlGaN材料,Au肖特基型探测器的光响应良好,达到0.10A/W,外量子效率峰值为47%,但暗电流稍大,为3.91×10^(-10)A/cm^(2)。而Ni/Au肖特基型探测器的暗电流稳定,普遍在4.17×10^(-11)A/cm^(2),而响应率一般,为0.07A/W,外量子效率为33%。测试结果与仿真模型基本一致,对正照式,受势垒高度和界面损耗层等因素影响,相较Ni/Au肖特基型探测器,Au肖特基型探测器的响应范围更大、响应率更高;对背照式,吸收层的厚度对响应范围有很大影响,薄吸收区有效展宽了响应区域。
For a Schottky detector with a thin absorption region of 100~200nm,the influence of different metal contacts on the dark current and spectral response characteristics was studied.Taking GaN-based materials as the main body,Au and Ni/Au were prepared on the surface of thin Al_(0.42)Ga_(0.58)N to form Schottky contacts,and Ti/Al/Ti/Au were prepared on the surface of Al_(0.55)Ga_(0.45)N to form ohmic contacts.Thus,an AlGaN Schottky solar-blind detector with a thin absorption region is fabricated.The results show that for AlGaN material,the photoresponse of Au Schottky detector is good,reaching 0.10A/W,the peak external quantum efficiency is 47%,but the dark current is slightly larger,which is 3.91×10^(-10)A/cm^(2).The dark current of Ni/Au Schottky detector is stable at 4.17×10^(-11)A/cm^(2),while the responsivity is generally 0.07A/W,and the external quantum efficiency is 33%.The test results are consistent with the simulation model.For the front irradiation mode,Au Schottky detector has a larger response range and higher responsivity than Ni/Au Schottky detector due to factors such as barrier height and interface loss layer.For the back irradiation mode,the thickness of the absorption layer has a great effect on the response range,and the thin absorption region effectively extends the response range.
作者
胡乐枫
张燕
HU Lefeng;ZHANG Yan(Key Lab.of Infrared Imaging Materials and Detectors,Shanghai Institute of Technical Physics of the Chinese Academy of Sciences,Shanghai 200083,CHN;University of Chinese Academy of Sciences,Beijing 100049,CHN)
出处
《半导体光电》
CAS
北大核心
2022年第3期510-516,共7页
Semiconductor Optoelectronics
基金
国家自然科学基金面上项目(61774162)。
