Growth of inassb and gainassb compounds on gaas substrate by mbe technique for infrared detector applicatons

In the scope of this thesis, high quality InAsSb/GaInAsSb ternary and quaternary compounds were grown on GaAs substrates by MBE technique and their structral, optical and opto-electronic properties were studied. The samples were grown systematically depending on the concentration by using either GaAs buffer layer or GaAs buffer layer with GaSb transition layer. Their crystal quality were investigated by means of high resolution X-ray diffraction technique. Etching rate of InAs1-xSbx epilayers were determined depening on the concentration for citric and hydrochloric acid solution. By Raman spectroscopy, their lattice dynamics were examined and it was shown that InAs1-xSbx (x≥0,55) structures exhibited two-mode InAs- and InSb-like longitudinal optical phonon frequencies. Furthermore, in acoustic phonon region these structures presented InSb-like mix-mode acoustic and all Raman frequency peak locations were defined by equations as a function of x concentration. The cutoff wavelengths and band gap energies of InAs1-xSbx photodetectors were determined and designed that they have a detection in mid-wavelength infrared region. The activation energies were obtained from temperature-dependent dark current measurements of the detector structure and found the mechanisms that affect the dark current. Band gap energies of GaxIn1-xAsySb1-y photodetectors were identified by using photoluminescence and photoresponse measurements. It was observed that the diodes have a photoresponse in the near infrared region.