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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]

In this study, the electrical properties of dilute nitride GaAsPN/GaPN multi-quantum well p- i- n diodes were investigated by using current-voltage ( I- V) measurements at room temperature. The diode structure was grown on silicon (Si) (100) substrate misoriented by 4° towards the [110] direction using the molecular beam epitaxy technique, and ohmic contacts were formed on this structure by metallization process. The forward bias I- V characteristics of the diode were analyzed by the thermionic emission theory. Ideality factor ( n), barrier height (Φ) and series resistance ( R ), which are the main electrical parameters of diodes, were determined from I- V characteristic, Norde and Cheung methods. The obtained experimental results were compared with each other. From the I- V characteristic, the values of n and Φ were found to be 2.86 eV and 0.69 eV, respectively. The barrier height values, which were obtained from the Norde function and I- V characteristic, were in good agreement with each other. It was also found that the values of series resistance determined from the Norde and Cheung functions were compatible with each other. [ABSTRACT FROM AUTHOR]

GZO thin films were succesfully deposited onto n-Si and glass substrates by RF magnetron sputtering at room temperature. The structural, morphological and opto-electrical properties of the films were investigated in terms of RF power, using various methods such as XRD, AFM, SEM, EDX, XPS, SIMS, UV-Vis-NIR spectroscopy and Hall effect measurements. The achieved results revealed that the all films have highly c-axis (002) oriented polycrystalline structure with high transmittance in Vis and high reflectance in NIR region as well as good conductivity. Meanwhile, surface of the films was uniform, compact and crack-free. With incerasing of RF power, it was seen that crystallinity of the films improved and the grain size became larger. It was also observed that optical band gap of the films was increased to the order of 0.15 eV as well as decreasing the resistivity to the order of 6.38 Ω cm with increasing RF power from 100 to 200 W. Deposited film at 200 W, which can be optimum sputtering power for coating GZO films, having high concentration of free electrons and lowest resistivity exhibited the highest IR reflectivity (~55%) in NIR region. In addition, deposited GZO films at this power have larger particle size and highly optical transmittance (~87%) in visible region. Obtained both of optical and electrical results suggested that the deposited GZO films can be used in low thermal emissivity coating for energy efficient glass and the UV-blocking layer as well as transparent conductive oxide electrode for flexible opto-electronic devices. [ABSTRACT FROM AUTHOR]