Recent advances in technology using ultra-thin noble metal film in oxide/metal/oxide structures have attracted attention because this material is a promising alternative to meet the needs of transparent conduction electrodes (TCE). AZO/ Ag/AZO multilayer films are prepared by magnetron sputtering for Cu2ZnSn(S,Se)4 (CZTSSe) of kesterite solar cells. It is shown that the electrical and optical properties of the AZO/Ag/AZO multilayer films can be improved by the very low resistivity and surface plasmon effects due to the deposition of different thicknesses of Ag layer between oxide layers fixed at AZO 30 nm. The AZO/Ag/AZO multilayer films of Ag 15 nm show high mobility of 26.4 cm2/Vs and low resistivity and sheet resistance of 3.58*10−5 Ωcm and 5.0 Ω/sq. Also, the AZO/Ag (15 nm)/AZO multilayer film shows relatively high transmittance of more than 65% in the visible region. Through this, we fabricated CZTSSe thin film solar cells with 7.51% efficiency by improving the short-circuit current density and fill factor to 27.7 mV/cm2 and 62 %, respectively.
Due to its favorable optical properties, Cu2SnS3 (CTS) is a promising material for thin film solar cells. Doping, which modifies the absorber properties, is one way to improve the conversion efficiency of CTS solar cells. In this work, CTS solar cells with selenium doping were fabricated on a flexible substrate using sputtering method and the effect of doping on the properties of CTS solar cells was investigated. In XRD analysis, a shift in the CTS peaks can be observed due to the doped selenium. XRF analysis confirmed the different ratios of Cu/Sn and (S+Se)/(Cu+Sn) depending on the amount of selenium doping. Selenium doping can help to lower the chemical potential of sulfur. This effectively reduces the point defects of CTS thin films. Overall improved electrical properties were observed in the CTS solar cell with a small amount of selenium doping, and a notable conversion efficiency of 1.02 % was achieved in the CTS solar cell doped with 1 at% of selenium.
Cu2ZnSn(S,Se)4(CZTSSe) thin film solar cells areone of the most promising candidates for photovoltaic devices due to their earth-abundant composition, high absorption coefficient and appropriate band gap. The sputtering process is the main challenge to achieving high efficiency of CZTSSe solar cells for industrialization. In this study, we fabricated CZTSSe absorbers on Mo coated soda lime glass using different pressures during the annealing process. As an environmental strategy, the annealing process is performed with S and Se powder, without any toxic H2Se and/or H2S gases. Because CZTSSe thin films have a very narrow stable phase region, it is important to control the condition of the annealing process to achieve high efficiency of the solar cell. To identify the effect of process pressure during the sulfo-selenization, we experiment with varying initial pressure from 600 Torr to 800 Torr. We fabricate a CZTSSe thin film solar cell with 8.24 % efficiency, with 435 mV for open circuit voltage(VOC) and 36.98 mA/cm2 for short circuit current density(JSC), under a highest process pressure of 800 Torr.
This study aimed to analyze factors of importance and performance picked by customers of Bibijeong, a farm restaurant operated by the local community of Wanju-gun. Major points include: Recognition paths mostly were word of mouth and mass media, types of visit were in the company of friends, family members or work colleagues, and purposes of visit included consumption of meal and identifying features of the restaurant. Secondly, factor analysis showed that level of facility, atmosphere/cleanness, diversity of menu, employees, ingredients and network. The Cronbach Alpha coefficient was +0.6. Thirdly, average of importance of factors was 3.861 while average performance was 3.429. IPA analysis showed that employee(communication, customer contact) in the first quadrant proved the need for fast improvement through training. Atmosphere/cleanness (interior atmosphere, table clean, kitchen cleanliness, clean dishes, interion design) and employee(proficiency, menu recognition), foodstuff(freshness, origin, safety) in the second quadrant showed that the marketing strategy of improvement as well as maintaining current status is needed, including regular training and hygiene inspection. The third quadrant contains facilities(disability, baby, fire protection) and food menu(food packing, various menu, creative menu, menu description), network(village economic links), which showed the need for gradual improvement. The forth quadrant contains network(sights’s near contains. The results so far can be summed into the statement that overcoming the basic functionality of providing meals and linking the restaurant with local attractions and local economy would be need, as well as building up the image of unique farm restaurant with local features, so that Bibijeong can serve as the centerpiece of community and foundation of exchange with other areas.