Study On Preparing Conductive CIGS Target

Energy crisis is getting more serious with the rapid development of human society.As a kind of clean and renewable energy, the solar power is more popular with manycountries. So they make great efforts to develop solar cell. GIGS thin film solar cell isconsidered as the third generation promising energy because of its excellent property. Inorder to reduce the production cost of GIGS thin film solar cell, the single target sputteringhas been exploited. But the resistivity of single target is so large that it can only be usedfor the RF sputtering, which limits the industrial production of CIGS battery. So thepurpose of this paper is to explore a single target with good electrical conductivity.In the experiment, using Copper(Cu)、Indium(In）、Gallium(Ga） and Selenium(Se)as raw materials. Using the quartz tube vacuum sealing technology to realizing thevacuum seal of the mixed powder that according to the stoichiometric ratio. Research thetechnology of preparation of single phase Cu2Se、In2Se3、Ga2Se3and CuIn0.7Ga0.3Se2, thenthe resistivity of these compounds were tested at room temperature, under25MPapressure. Heating to300℃and preservation for3hours, can get a single-phase of Cu2Se,its resistivity is0.022Ω cm; Heating to650℃and preservation for3hours, can get asingle-phase of In2Se3, its resistivity is4.2Ω cm; Heating to885℃and preservation for12hours, can get a single-phase of Ga2Se3, its resistivity is1.03*107Ω cm; Heating to1000℃and preservation for3hours, can get a single-phase of CuIn0.7Ga0.3Se2, its resistivity is379.5Ω cm.In the experiment, using the CIGS powder that prepare under different temperaturesand mixture powder of Cu2Se、In2Se3and Ga2Se3according to the stoichiometric ratio asraw material. Then using SPS sintering technology to preparing the target material andalso using a single variable contrast experiment, to explore the influence of sinteringtemperature、holding time、sintering pressure and sintering atmosphere to the propertiessuch as relative density and resistivity of CIGS target. The result showed that highersintering temperature and longer time of heat preservation, the relative density and resistivity of target are increased. Pressure increases, the relative density of targetincreases and its electrical resistivity decreased; Vacuum sintering atmosphere of the targetperformance is better than that target under argon protection.Using SPS sintering technique, the temperature is lasting for5minutes at600℃.Under the condition of vacuum, with the CIGS powder obtained at650℃as raw material,the sintering pressure is30MPa, as a result, the relative density of target is97.83%, itsresistivity is52.1Ω cm, when the temperature is lasting for5minutes at850℃, therelative density of target is98.97%; with the mixed powder of Cu2Se、In2Se3、Ga2Se3asraw material, the sintering pressure is25MPa. The relative density of target is96.68%, itsresistivity is7.1Ω cm. Most of the target is the phase of CuIn0.7Ga0.3Se2.