Electron beam-induced absorption modulation imaging of strained In0.2Ga0.8As/GaAs multiple quantum wells
نویسندگان
چکیده
We have examined the effects of electron-hole plasma generation on excitonic absorption phenomena in nipi-doped In&&,sAs/GaAs multiple quantum wells (MQWs) using a novel technique called electron beam-induced absorption modulation imaging. The electron-hole plasma is generated by a high-energy electron beam in a scanning electron microscope and is used as a probe to study the MQW absorption modulation. The inlluence of structural defects on the diffusive transport of carriers is imaged with a ,um-scale resolution.
منابع مشابه
Ambipolar diffusion anisotropy induced by defects in nlpi-doped In0.2Ga0.8As/GaAs multiple quantum. wells
The infIuence of strain-induced defects on the ambipolar diffusive transport of excess electrons and holes in the &doped InGaAs/GaAs multiple quantum well system has been examined with a new technique called electron-beam-induced absorption modulation (EBIA). The excess carrier lifetime and diffusion coefficient are obtained by a one-dimensional diffusion experiment that utilizes EBIA. An aniso...
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