HEMT太赫兹探测器响应度和NEP的检测与分析

在0.8～1.1 THz内,对AlGaN/GaN高电子迁移率晶体管(HEMT)太赫兹探测器的响应度和噪声等效功率进行了具体测试和分析。在太赫兹波辐射下,HEMT太赫兹探测器源漏端产生能被栅压灵敏调控的直流光电流。该型探测器在300 K和77 K下的电流响应度分别为83 mA/W和4.1 A/W,电压响应度分别为4 kV/W和50 kV/W,噪声等效功率分别达到22 pW/Hz0.5和1 pW/Hz0.5。采用两种较为典型的测量方法,通过对实验结果的比较,确定了影响该类型探测器的响应度和噪声等效功率的主要因素,并提出了增强响应度和降低噪声等效功率的具体措施。

Detection and Analysis of the Responsivity and NEP for HEMT Terahertz Detectors

The responsivity and noise equivalent power(NEP) of the terahertz detectors based on the AlGaN/GaN high electron mobility transistor(HEMT) were tested and analyzed at 0.8-1.1 THz.Under the terahertz wave irradiation,the DC photocurrent sensitively modulated by the gate voltage was observed at the source-drain end of the HEMT terahertz detector.At 300 K and 77 K,the current responsivities are 83 mA/W and 4.1 A/W,the voltage responsivities are 4 kV/W and 50 kV/W,the noise equivalent powers are 22 pW/Hz0.5 and 1 pW/Hz0.5,respectively.Through two kinds of the typical measurement methods and the comparison of the experimental results,the main factors affecting the responsivity and noise equivalent power of the detector were identified,and the specific measures to enhance the responsivity and reduce the noise equivalent power were proposed.