Investigation of the optical properties of the au/n-gaas metal semiconductor contacts

In this study, Au/n-GaAs structures were prepared on n-type GaAs semiconductor with orientation (111) and having 400 ?m thickness and carriers concentration of 1x1017cm-3 by metal evaporation method. Characteristics of current-voltage (I-V) at room temperature under light and darkness and characteristics of capacitance-voltage (C-V) which is bound to frequency range of 10 KHz-1,2 MHz has been analyzed. Density of interface state values has been evaluated and it has been noticed that it decreases as frequency increases. Prepared structure's current-voltage (I-V) specifications have been analyzed under 80K-380K temperature changes and ideality factor n, Schottky barrier heights ?B and other related diode parameters has been evaluated. At room temperature, it has been calculated for barrier heights as 0,644 eV and for ideality factor as 1,86. It has been observed that ideality factor decreases barrier height increases as temperature increases. At 1 MHz frequency, capacitance-voltage (C-V) specifications with changing temperature have been analyzed. Using these data, diffusion voltage VD, barrier height ?B, concentration of donor ND and width of depletion layer WD has been calculated. At room temperature barrier height value has been calculated as 0,91 eV. Current-voltage (I-V) has been measured with different output powers of 5-250 W using the Light Source. Solar cell parameters using data gathered from this measurement has been evaluated. Fill factor has been found as 68,90 and efficiency as 12,20%, with the Light Source having 250 W of power output. Barrier heights and ideality factors of Schottky diodes have been analyzed using filters with different wavelengths in five different powers of light sources ranging from 50 to 250 W. It has been observed that barrier heights and ideality factor changes with changing light frequency. Solar cell parameters have been analyzed for 250 W of output power for all filters.