Study On Preparation And Process Test Of Silicon Nitride Film In Metal Film Sensor

In metal thin film sensors,dielectric thin films are often used to insulate the metal substrate from the sensing element,protecting the sensitive components from external environmental contamination to ensure accurate stability during the measurement.Silicon nitride has attracted much attention in the field of micro-mechanical and microelectronics and material modification because of its high tensile strength,hardness,specific resistance,high dielectric constant,excellent insulation,and other mechanical and electrical properties.At the same time,the preparation technology and structure of the silicon nitride film were studied at home and abroad.However,the influence of deposition parameters on the deposition rate,film uniformity,film roughness and the influence of deposition parameters and the effect of annealing heat treatment on the structure of the thin film were insufficient studied.There are still few studies,and there are few researches on the preparation of silicon nitride film on metal substrate.Combined with the metal substrate to explore the preparation of silicon nitride film process for the future preparation of metal thin film sensor has laid a solid foundation for the process and has important practical significance.Based on the monocrystalline silicon target and the silicon nitride target,silicon nitride film for the insulating layer and the protective layer of the metal thin film sensor was deposited by RF magnetron sputtering method on metal substrate.The repairing was conducted using various measuring devices to analysis and test the film thickness,surface roughness,surface morphology,composition,crystal structure and film hardness of the prepared samples.Based on the single factor test,the effects of sputtering power,working pressure,gas flow ratio and substrate temperature on the deposition rate,surface uniformity and surface roughness were studied.Based on the silicon nitride target,explores the influence of sputtering power,working pressure and nitrogen flow rate on the film quality.Focusing on single crystal silicon target preparation of the film when the deposition parameters of the design of orthogonal test.Through the analysis of the difference and variance to study on the influence degree and significance of the four deposition parameters on the film quality characteristics and three empirical model formulas for deposition rate,film uniformity and surface roughness were established respectively.The results show that the surface defects are less in the range of 100W~120W and the quality is the best and when the substrate temperature is about 200℃.the film quality is compact and the hardness is 1532.6HV.With the increase of nitrogen flow,the hardness of the film increases first and then decreases that at 15 sccm when the maximum hardness is 1240.3HV.The XRD patterns and EDS electron spectroscopy analysis show that the prepared films are amorphous silicon nitride and the annealing temperature is not higher than 1000℃,the crystal structure is almost no change.