Ultrafast Phenomena in Freestanding LT-GaAs Devices
English
Marso, Michel[Institute of Thin Films and Interfaces, Research Centre Jülich, D-52425 Jülich, Germany]
Mikulics, M.[Institute of Thin Films and Interfaces, Research Centre Jülich, D-52425 Jülich, Germany, and Max-Planck-Institut fÄur Radioastronomie, 53121 Bonn, Germany]
Adam, R.[Institute of Thin Films and Interfaces, Research Centre Jülich, D-52425 Jülich, Germany]
Wu, S.[Department of Electrical and Computer Engineering, and the Laboratory for Laser Energetics, University of Rochester, Rochester]
Zheng, X.[Department of Electrical and Computer Engineering, and the Laboratory for Laser Energetics, University of Rochester, Rochester]
12th International Symposium on Ultrafast Phenomena in Semiconductors (12-UFPS)
August 22-25, 2004
Vilnius
Lithuania
[en] We report on the fabrication and high-frequency performance of our photodetectors and photomixers based on freestanding low-temperature-grown GaAs. The MBE-grown low-temperature GaAs layers are lifted from the native GaAs substrate and transferred on top of variety of host substrates. The freestanding devices exhibit breakdown electrical ¯elds above 200 kV/cm and dark currents below 3 £ 10¡7 A at 100 V bias. Device photoresponse shows 0.55 ps wide electrical transients with voltage amplitudes up to 1.3 V, measured using an electro-optical sampling technique with 100 fs wide laser pulses. Photomixing experiments at 460 GHz yield a 9 times higher output power for the freestanding device on Si/SiO2 host substrate compared to the native substrate.