AlGaAs／GaAs多量子阱光电压的真空敏感特性

Vacuum Sensitivity of AlGaAs/GaAs multiple-Quantum-Wells Photovoltage

通过测量在不同真空度中的室温光电压谱，发现ＡｌＧａＡｓ／ＧａＡｓ多量子阱的光电压对真空度很敏感。在１个大气压的气氛中，光电压随光子能量的增大呈台阶状下降；而在０．ｌＰａ真空度中，光电压随光子能量的增大呈台阶状上升。本文认为，光电压与真空度有关主要归因于ＡｌＧａＡｓ／ＧａＡｓ多量子阱表面吸附的氧原子的作用，文中对实验现象进行了分析讨论。

In measuring the photovoltage spectra at room temperature in different vacua,it is found that the photovoltage of AlGaAs/GaAs multiple quantum wells is very sensitive to vacua.With the increase of photon energy,the photovoltage decreases at l atmosphere,and increases at 0.1 Pa,both in a step-like manner.It is then belivevd thatthe sensitivity of photovoltage to vacua lies in the action of the oxygen atoms absorbedon the surface of AlGaAs/GaAs multiple quantum wells.An analysis and discussion aremade in this paper of the observations in the experiments.