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The structural, optical and electrical properties of dilute nitride p-n junction GaPAsN structures grown on n-type GaP (100) and n-type Si (100) misoriented by 4° towards the [110] direction substrates were studied. These properties of the samples, which were grown by using molecular beam epitaxy (MBE) technique, were investigated by using high-resolution X-Ray diffraction (HRXRD), energy dispersive X-Ray (EDX), room temperature photoluminescence (PL) and current-voltage ( I-V) measurements. Both alloy composition values (x, y) and crystal structure parameters were determined from HRXRD measurements while the band gap energies were obtained from PL measurements. Composition values were also determined by using EDX measurements and compared with HRXRD results. The better crystal quality was found for the sample grown on GaP substrate from both the HRXRD and PL results. In addition, the theoretical band gap energies calculated from the band anticrossing (BAC) model and experimental band gap energies determined from the PL measurements were compared and found to be in good agreement with each other. The p-n junction GaPAsN/GaP (Si) diode devices were fabricated to investigate their electrical properties. The I-V characteristics of diodes were analyzed at room temperature and the diode formed on GaP substrate exhibited better results compared to other diode. [ABSTRACT FROM AUTHOR]

• CuZnSn precursor stacks were deposited on Mo-coated soda lime glass by co-sputtering • Cu 2 ZnSnS 4 (CZTS) films were obtained at different sulfurization times in a furnace • Developed CZTS films in kesterite structure had a direct band gap of around 1.4 eV • CZTS films had uniform morphologies, densely packed structures without any cracks In this work, Cu 2 ZnSnS 4 (CZTS) absorber films were prepared by sulfurization of co-sputtered precursor films at different time periods. The influence of sulfurization time on physical characteristics of the grown films was investigated in detail. The sulfurized CZTS films exhibited the characteristic diffraction peak of the kesterite phase corresponding to the (112) crystal plane, the main Raman mode of kesterite phase at around 337 cm−1 and Cu-deficient and Zn-rich composition. From the atomic force microscopy surface and cross-sectional scanning electron microscopy images, it was revealed out that the films were uniform, compact without any cracks and consisted of micron-sized and closely packed grains. In addition, the films showed tail-to-tail, band-to-tail and band-to-band transitions at around 1.41 eV (E 1), 1.45 eV (E 2) and 1.51 eV (E 3), respectively. Secondary ion mass spectroscopy analysis showed that the sodium ions deeply diffused through the molybdenum layer into the CZTS film from the soda lime glass substrate for all samples. All of the films exhibited an optical band gap of around 1.4 eV, an absorption coefficient over 104 cm−1, p-type conductivity with a high concentration of free holes in the order of 1017-1018 cm−3 and low mobility in the range from 0.63 cm²/V.s to 8.11 cm²/V.s. [ABSTRACT FROM AUTHOR]