Ion Beam Assisted Deposition Technology And Structure Of AlN/Al₂O₃ Insulating Films

The substrate of thin film sensor is generally made of metal,and the loss of electrical signals will occur in the substrate,leading to inaccurate measurement and even failure of the sensor.It is very important to prepare an insulating film between the sensor functional layer and the metal substrate.Its performance will directly affect the precision and stability of the thin film sensor on the metal substrate.In this paper,AlN/Al₂O₃ insulating films were prepared by ion beam-assisted deposition.The effects of ion/atom arrival ratio(IAR)and thickness on the chemical composition,phase structure,surface morphology and electrical insulation properties of AlN/Al₂O₃ monolayer films were studied.The influence of modulation ratio on the electrical insulation performance of AlN/Al₂O₃multilayer insulating film is discussed,and the following conclusions are drawn:(1)For AlN films,when IAR is low,The aluminum did not react completely in the film,and the film was fibrous,cracking and peeled off.With the increase of IAR,the aluminum decreases gradually.When IAR is 2.0,the film composition is AlN and less Al O_xN_y,The defect of the film is reduced and the density is increased.When IAR<2.7,The leakage current of A-Order,and when IAR is 2.7,the film has the best electrical insulation and leakage current of?A-Order.(2)When IAR is 1.0-5.3,Al₂O₃ thin film is mainly composed of amorphous and conforms to the standard stoichiometric ratio.The surface of Al₂O₃ thin film is dense.The leakage current of Al₂O₃ thin film is?A-Order,which shows the properties of dielectric materials.When IAR>3.2,the micro-bulge on the film surface increase significantly,the breakdown probability increases,and the electrical insulation performance decreases.(3)When the thickness of AlN film is 780 nm,the surface of AlN film is dense,the grain size is small,the grain boundary is more,and the electrical insulation performance is the best.With the increase of the thickness,the surface micro-bulge increase,the breakdown probability increases,and the electrical insulation performance decreases.When the thickness of Al₂O₃ film is 570 nm,the electrical insulation performance is the best.(4)The breakdown current of AlN/Al₂O₃ multilayer is?A-Order.With the increase of modulation ratio,the breakdown probability of AlN/Al₂O₃ multilayer decreases first and then increases,and the electrical insulation performance increases first and then weakens.When the modulation ratio is 1:3,the electrical insulation performance of AlN/Al₂O₃ multilayer film is the best.