Molecular beam epitaxy growth of TmP/GaAs and transistor action in GaP/TmP/GaAs heterostructures

The growth of thulium phosphide (TmP) by molecular beam epitaxy (MBE) on GaAs substrate is reported. Good epilayer quality was demonstrated through X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM) analysis. The closely lattice matched TmP layer was n-type with an electron concentration of 1.6/spl times/10/sup 21/ cm/sup -3/ and a room temperature mobility of 4.8 cm/sup 2/V/sup -1/s/sup -1/. The Schottky barrier height determined from 1/capacitance/sup 2/ (1/C/sup 2/) versus voltage (V) measurements is about 0.81 eV which agrees well with the value obtained through the current-voltage (I-V) measurements. In this work, we also report transistor action in a GaP/TmP/GaAs structure, for which chemical bonding techniques were employed. From I-V measurements, a common base current gain /spl alpha//spl ap/0.55 at V/sub CB/=0 was obtained at room temperature.