Mbe growth and determination of physical properties of AlxGa1-xAs/GaAs quantum well infrared photodetector structures

In this work,AlxGa1-xAs/GaAs (x=0.20, 0.22) kuantum two well infrared photodetector structures and a AlGaAs/GaAs calibration sample were grown using the molecular beam epitaxy (MBE). AlGaAs/GaAs materials are used for infrared detector technologies because they have very good lattice matching and growing by MBE perfectly. Structural properties of fotodetectors were carried out by high resolution x-ray diffraction and photoluminescence measurements. Electrical parameters of the detectors and calibration sample determined by using Hall effect measurements. After the fabrication of the detectors, dark current-voltage characteristics as a function of temperature were done. Dark current values at high temperature region were explained with thermionic emission theory. Measurements show that detector with band-to-continuum states transport has lower dark current than detector with band-to-band transport as 103 order.