Au-MgO-ZnO （AMZ） ultraviolet （UV） photodetectors were fabricated to enhance their sensitivities by an inserting ultrathin insulating MgO layer. With the insulating layer, the sensitivities of the UV photodetectors...Au-MgO-ZnO （AMZ） ultraviolet （UV） photodetectors were fabricated to enhance their sensitivities by an inserting ultrathin insulating MgO layer. With the insulating layer, the sensitivities of the UV photodetectors were improved via the reduction of the dark current. Furthermore, strain modulation was used to enhance the sensitivities of the AMZ UV photodetectors. The sensitivities of the photodetectors were enhanced by the piezo-phototronic effect. However, there was a limiting value of the applied strains to enhance the sensitivity of the photodetector. When the external strains exceeded the limiting value, the sensitivity decreased because of the tunneling dark current. The external strains loaded on the photodetectors result in the degradation of the photodetectors, and an applied bias can accelerate the process. This work presents a prospective approach to engineer the performance of a UV photodetector. In addition, the study on the service behavior of the photodetectors may offer a strain range and theoretical support for safely using and studying metal-insulator-semiconductor （MIS） UV photodetectors.展开更多
The band structure of the confined states is calculated for Si/SiGe multi-quantum well infrared photodetector(M-QWIP).The influence of the Ge component in pseudosubstrate on the energy band structure of Si/Si0.54Ge0.4...The band structure of the confined states is calculated for Si/SiGe multi-quantum well infrared photodetector(M-QWIP).The influence of the Ge component in pseudosubstrate on the energy band structure of Si/Si0.54Ge0.46 multi-quantum wells(MQWs) is investigated.It is found that the high energy levels in the MQWs move up while the low energy levels move down as the Ge component in pseudosubstrate increases.The influence of the barrier width on the energy band structure of MQWs is also studied based on the 6 × 6 k.p method.The results show that the Si barrier between 5 nm and 10 nm is optimized to enhance the intersubband absorption in the MQWs.展开更多
文摘Au-MgO-ZnO （AMZ） ultraviolet （UV） photodetectors were fabricated to enhance their sensitivities by an inserting ultrathin insulating MgO layer. With the insulating layer, the sensitivities of the UV photodetectors were improved via the reduction of the dark current. Furthermore, strain modulation was used to enhance the sensitivities of the AMZ UV photodetectors. The sensitivities of the photodetectors were enhanced by the piezo-phototronic effect. However, there was a limiting value of the applied strains to enhance the sensitivity of the photodetector. When the external strains exceeded the limiting value, the sensitivity decreased because of the tunneling dark current. The external strains loaded on the photodetectors result in the degradation of the photodetectors, and an applied bias can accelerate the process. This work presents a prospective approach to engineer the performance of a UV photodetector. In addition, the study on the service behavior of the photodetectors may offer a strain range and theoretical support for safely using and studying metal-insulator-semiconductor （MIS） UV photodetectors.
基金supported by the National Natural Science Foundation of China (No.60837001)the Major State Basic Research Development Program of China (No.2007CB613404)
文摘The band structure of the confined states is calculated for Si/SiGe multi-quantum well infrared photodetector(M-QWIP).The influence of the Ge component in pseudosubstrate on the energy band structure of Si/Si0.54Ge0.46 multi-quantum wells(MQWs) is investigated.It is found that the high energy levels in the MQWs move up while the low energy levels move down as the Ge component in pseudosubstrate increases.The influence of the barrier width on the energy band structure of MQWs is also studied based on the 6 × 6 k.p method.The results show that the Si barrier between 5 nm and 10 nm is optimized to enhance the intersubband absorption in the MQWs.
