The Effect Of Magnetron Sputtering And Annealing Parameters On The Microstructure And Properties Of Polycrystal-Si Film

Silicon has become a main raw material in photovoltaic industry with its matureproduction technology, high photoelectric conversion efficiency and the advantages ofnon-toxic material. At present, the cost of production of silicon solar cells is higher. Toreduce costs, the study of high performance silicon thin film solar cell is important.Meanwhile, there are many techniques to prepare the film, and the advantages ofmagnetron sputtering deposition film are fast speed、low cost、simple equipment. If wecan fabricate silicon thin film solar cells with magnetron sputtering, it will be able toreduce the cost of solar cells. Therefore, in this paper, we prepared n-type silicon filmon the p-type single crystal silicon substrate using magnetron sputtering, then annealedthe film and made the film crystallization to form monocrystallinesilicon/polycrystalline silicon p-n junction.The structure、morphology of the film andproperties of p-n junctions were respectively characterized. The main contents are asfollows:The sputtering process parameters have an effect on the structure and compositionof n-type silicon thin films:with the heavy boron-doped p-type single-crystal silicon assubstrates, heavy phosphorus-doped n-type monocrystalline silicon as the target, weobtained n-type Si thin film in the use of magnetron sputtering method under differentsputtering process parameters. The Si layer of amorphous structure are preparedwherein the substrate was heated in favor of crystallization of the film. Si surfaceroughness and deposition rate of the film were affected by the sputtering power andsputtering pressure. In addition, the sputtering power and sputtering pressure alsoaffected the P-doped n-type Si film.Annealing process parameters had an effect on the structure and properties ofn-type polycrystalline silicon thin films. Under the protection of argon, using differentannealing temperatures anneal the n-type silicon film which grew on the p-typemonocrystalline silicon substrate. The higher the annealing temperature was, the betterthe degree of crystallization of the film was. And the grain size of the film annealed at1000℃was about10nm. After annealing under high temperature, P impurity in n-typeSi film was well immersed into the lattice. Furthermore, the annealing temperature alsohad an impact on the film surface morphology and optical properties of the film. The preparation and performance study of monocrystalline silicon/polycrystallinesilicon p-n junctions: the Al electrode was respectively deposited on p-type and n-typesilicon film, then we made a study of the Si/Al ohmic contact, and p-n junction caused ashort circuit phenomenon between the Si and Al after annealing under500℃, due to thetip of the wedge Al. So we prepared a good Si/Al ohmic contact under400℃. Due tothe higher doping concentration of the p-n junction, the potential barrier area of the p-njunction prepared was small.