Study On Preparation And Properties Of ITO Thin Films And Its Application In Hit Solar Cells

In this thesis, the indium tin oxide ceramic target with the purity of99.999%was chosenas sputtering target, on this condition, ITO thin flms were deposited on glass substrates byMid-Frequency Pulsed Magnetron Sputtering. The effects of process parameters on theproperties of ITO thin films were investigated, meanwhile, the spectroscopic reflectometerfilm thickness measurement system, XRD, SEM, Four-probe and solar cells’ spectralperformance test system were applied to show the thickness, crystal structure, surfacemorphology and photoelectric properties of ITO thin films deposited in experiments.Besides, optimized ITO thin films were applied to HIT solar cells. Several importantachievements have been carried out as follows：1. ITO thin flms were deposited at different process parameters by Mid-FrequencyPulsed Magnetron Sputtering, and the influences of substrate temperature, sputteringpressure, sputtering power, proportion of oxygen and argon gas on the films’ crystalstructure, surface morphology, thickness, deposition rate and photoelectric properties werestudied, at the same time, the general rules of the change of the films’ properties at differentprocess parameters were mastered.2. Through a lot of experiments and analysis, the optimum process parameters ofdepositing ITO thin flms was achieved. Experimental investigation shows that when thesubstrat temperature is350℃, sputtering power is120W, sputtering pressure is1.5mtorr,proportion of oxygen and argon gas is0.4:40and the sputtering time is45min, ITO thinfilms’ properties are best and high quality ITO thin films could be obtained.3. When the optimized ITO thin films were applied to HIT solar cells, the HIT solar cellwhose open circuit voltage is0.56V, short-circuit current density is36.28mA·cm-2, fillfactor is0.693and conversion efficiency is14.04%was achieved. Through comparing theHIT solar cell’s properties with ITO thin films before and after optimization, We found thatthe HIT solar cell’s short-circuit current density, fill factor and efficiency were all improvedand the properties of ITO thin films have an important influence on HIT solar cell’sperformance.