Deep levels in GaInAs grown by molecular beam epitaxy and their concentration reduction with annealing treatment

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X-ray diffraction (XRD), current–voltage ( IV ), capacitance–voltage ( CV ), deep-level transient Fourier spectroscopy (DLTFS) and isothermal transient spectroscopy (ITS) techniques are used to investigate the thermal annealing behaviour of three deep levels in Ga 0.986 In 0.014 As heavily doped with Si (6.8 × 10 17 cm −3 ) grown by molecular beam epitaxy (MBE). The thermal annealing was performed at 625 °C, 650 °C, 675 °C, 700 °C and 750 °C for 5 min. XRD study shows good structural quality of the samples and yields an In composition of 1.4%. Two main electron traps are detected by DLTFS and ITS around 280 K, with activation energies of 0.58 eV and 0.57 eV, capture cross sections of 9 × 10 −15 cm 2 and 8.6 × 10 −14 cm 2 and densities of 2.8 × 10 16 cm −3 and 9.6 × 10 15 cm −3 , respectively. They appear overlapped and as a single peak, which divides into two smaller peaks after annealing at 625 °C for 5 min. Annealing at higher temperatures further reduces the trap concentrations. A secondary electron trap is found at 150 K with an activation energy of 0.274 eV, a capture cross section of 8.64 × 10 −15 cm 2 and a density of 1.38 × 10 15 cm −3 . The concentration of this trap level is also decreased by thermal annealing.