Study On The Structure And Properties Of CuInTe₂ Optoelectronic Materials

The solar energy utilization is one of the effective ways to solve the energy problem because it's renewable and pollution-free.The solar cell is an important form of solar energy utilization performance.The forbidden band width of CuInTe₂ is about 1.06eV,and the forbidden band width can be adjusted by doping Ga or Al.The geometrical structure,forbidden band width and optical properties of CuInTe₂ were analyzed by the theoretical calculation based on the first principles.The three element compounds such as CuInTe₂,CuGaTe₂ and CuAlTe₂ are prepared by spin-coating and co-reduction method,and then doping Ga or Al in CuInTe₂.The structure and performance were analyzed by using XRD,SEM,EDS and four probe resistors.?1?The structure optimization,energy band and optical properties were calculated by CASTEP program.The cell volume of CuInTe₂,CuGaTe₂ and CuAlTe₂ increases by optimizing the structure,but the trend that three cell volume decreasing unchanged.It was found that the cell volume of CuInTe₂ decreases by doping Ga or Al after structural optimization,and the cell volume decreases with the increase of the amount of doping.After the energy is calculated,it was found that the forbidden band width increases with the increase of doping Ga or Al,but the variation range is within the range of CuInTe₂ and CuAlTe₂.The forbidden band width can be continuously adjusted in this range by changing the doping amount.The absorption rate of CuInTe₂ reaches peak at the wavelength of 250nm,and the peak value increases with the increase of dopant content.The absorption rate is 4.0×10⁴cm^-11 in the visible wavelength range,which can maintain a good absorptivity.?2?The crystallization effect of CuInTe₂ prepared by chloride system at different reaction temperatures was studied,it was found that the CuInTe₂ thin films were successfully prepared at 180?²20?.The crystallization of CuInTe₂ film prepared at different time in this temperature range were studied,and successfully prepared.It was found that the crystallization effect was better than that of the chlorinated object and the crystallization was best at 200?for 20h.It was found that the probability of successful preparation of CuInTe₂films is improved and the crystallization effect is effectively improved by increasing the number of reactions,while the heating treatment process has not achieved the expected effect.The films can keep continuous and dense in a certain range by SEM,and it contains Cu,In and Te elements by EDS.The resistivity and electrical conductivity of the films measured by the four probe resistor agree with the semiconductor range.However,the test results will be greatly influenced due to the poor surface compactness of the films.?3?The crystallization effect of CuGaTe₂ film synthesized at 180?²20?for different time was studied.It was found that the films were successfully prepared,but the crystallization effect was not good.The crystallization was best at 200?for 20h.The films can keep continuous and dense by SEM,and it contains Cu,Ga and Te elements by EDS.The crystallization effect of CuAlTe₂ films synthesized at different reaction temperatures was studied.It was found that the films were not successfully obtained,and only Te single crystals was obtained.The crystallization effect of CuIn_1-x-x Ga_xTe₂ films synthesized at 180?²20?for different time was studied.It was found that the films were not obtained,and only Te single crystals was obtained.