Ultrafast photoconductive switches fabricated by nano-anodization process on nano-clusters of InGaAs

Summary form only given. We have fabricated ultrafast photoconductive switches by a nano-anodization process using an atomic force microscope (AFM) on nano-clusters of InGaAs. The thickness of the nano-cluster layer is 2000 nm, and is grown on a InAlAs buffer layer on InP substrate. The nano-cluster makes the carrier lifetime shorter and the density of the deep level may be reduced compared to low-temperature grown GaAs. The nano-cluster layer is made by molecular beam epitaxy (MBE) at the growth temperature of 470/spl deg/C. The streak pattern of the reflection high energy electron diffraction (RHEED) was observed clearly. The AFM image of the InGaAs nano-cluster layer and the impulse response from the switch on a nano-cluster layer are shown The full width at half maximum is 390 fs at the bias voltage of 20 V. The slow tail components are dramatically reduced because of the short carrier time of the nano-cluster layer.