The growth, fabrication, and characterization of a solar-blind A1GaN-based p-i-n back-illuminated photodetector with a high temperature A1N template are reported for the first time. The photodetector was fabricated fr...The growth, fabrication, and characterization of a solar-blind A1GaN-based p-i-n back-illuminated photodetector with a high temperature A1N template are reported for the first time. The photodetector was fabricated from multilayer AIx Gal-xN films grown by MOCVD on double-polished c-plane （0001） sapphire substrates. Crack free, high A1 content （0.7） A1GaN multilayer structure,designed for the solar-blind p-i-n back-illuminated photodetector,was grown on a high temperature A1N template without a nuclear layer. The high quality of the epitaxial layers is demonstrated by in-situ optical reflectance monitoring curve, triple-axis X-ray diffraction, and atomic-force microscope. At a 1.8V bias, the processed p-i-n photodetector exhibits a solar-blind photoresponse with a maximum responsivity of 0. 0864A/W at 270nm. The photodetector exhibits a forward turn-on voltage at around 3.5V and a reverse breakdown voltage above 20V, and the leakage current is below 20pA for 2V reverse bias.展开更多
Neutron dose radiation experiment is designed to study the optocoupler＇s displacement effects and the noise characteristics. The burst noise is introduced in optocouplers on neutron radiation, which is indicated from...Neutron dose radiation experiment is designed to study the optocoupler＇s displacement effects and the noise characteristics. The burst noise is introduced in optocouplers on neutron radiation, which is indicated from experiments. With the increasing neutron radiation the displacement defects in space-charge region increase, the scattering enhances and the noise signal mutations increase. All these represent the noise time series mutations, the random pulses and the increasing noise complexity. The burst noise becomes evident, and the power spectrum density, the characteristic frequency and the fractal dimension of time series of noise greatly increase.展开更多
文摘The growth, fabrication, and characterization of a solar-blind A1GaN-based p-i-n back-illuminated photodetector with a high temperature A1N template are reported for the first time. The photodetector was fabricated from multilayer AIx Gal-xN films grown by MOCVD on double-polished c-plane （0001） sapphire substrates. Crack free, high A1 content （0.7） A1GaN multilayer structure,designed for the solar-blind p-i-n back-illuminated photodetector,was grown on a high temperature A1N template without a nuclear layer. The high quality of the epitaxial layers is demonstrated by in-situ optical reflectance monitoring curve, triple-axis X-ray diffraction, and atomic-force microscope. At a 1.8V bias, the processed p-i-n photodetector exhibits a solar-blind photoresponse with a maximum responsivity of 0. 0864A/W at 270nm. The photodetector exhibits a forward turn-on voltage at around 3.5V and a reverse breakdown voltage above 20V, and the leakage current is below 20pA for 2V reverse bias.
文摘Neutron dose radiation experiment is designed to study the optocoupler＇s displacement effects and the noise characteristics. The burst noise is introduced in optocouplers on neutron radiation, which is indicated from experiments. With the increasing neutron radiation the displacement defects in space-charge region increase, the scattering enhances and the noise signal mutations increase. All these represent the noise time series mutations, the random pulses and the increasing noise complexity. The burst noise becomes evident, and the power spectrum density, the characteristic frequency and the fractal dimension of time series of noise greatly increase.
