Preparation And Properties Of Al₂O₃ Thin Film By DC Magnetron Sputtering And RF Magnetron Sputtering

Precision processing and manufacturing technology continues to develop,requiring thin film sensor with a small,high sensitivity,high resolution,high temperature and so on in harsh environments to work properly.And the preparation of high surface quality,good insulation,anti-damage and strong sensor substrate insulation film is to obtain excellent performance of thin film sensor one of the key technologies.In this paper,DC magnetron sputtering and RF magnetron sputtering technology for the preparation of Al₂O₃ insulating layer in the sensor,and the process and performance research,to guide the thin film sensor process design and application of rapid development,has a very important theoretical significance and good engineering application value.Based on the analysis of the performance requirements of the thin film sensor insulating film and the principle of magnetron sputtering,the Al₂O₃ thin film was deposited on the slides and silicon substrate under DC and RF conditions.The effects of different sputtering target power,O₂ flow rate,working pressure,negative bias voltage and background vacuum on the deposition rate,surface roughness,surface morphology and phase structure of DC and RF were studied by single factor test.The results show that the DC method is in the range of certain process parameters,with the increase of sputtering target power,the deposition rate of Al₂O₃ thin film increases,and the surface roughness of the film increases.When the O₂ flow rate increases,the deposition rate of the Al₂O₃ film decreases,and the surface roughness of the film decreases first and then remains unchanged.With the increase of the working pressure,the deposition rate of Al₂O₃ thin film increases first and then decreases,reaching the maximum rate at 1.0Pa,and the surface roughness of the film decreases first and then remains unchanged.When the negative bias voltage is increased,the deposition rate of the film is decreasing.When the vacuum degree of the background is increased,the deposition rate of the film is increasing.When the RF method is adopted,the deposition rate and the surface roughness of the Al₂O₃ film increase with the increase of the sputtering target power.When the O₂ flow rate increases,the deposition rate of Al₂O₃ thin film decreases and the surface roughness decreases first and then remains unchanged.With the increase of the working pressure of the reaction chamber,the deposition rate of Al₂O₃ film does not changed first and then decreases,and the surface roughness of Al₂O₃ film increases first and then remains unchanged.The deposition rate of the film increases with the increase of the background vacuum.DC and RF to prepare a transparent and uniform surface of the film in the O₂ flow rate of 0.8sccm,1.0sccm,1.2sccm.The Al₂O₃ thin film prepared by different O₂ flow is amorphous structures at room temperatureBased on the single factor experiment,the orthogonal test was designed to study the effect of sputtering target power,O₂ flow rate and working pressure on the deposition rate of Al₂O₃ thin film under the DC and RF method.The results of orthogonal test were analyzed by difference and variance.The preparation parameters of DC and RF films were obtained and the films were prepared.The deposition time,film surface roughness and film hardness of the film were tested and compared.The optimized DC sputtering process parameters were selected and the preparation of the Al₂O₃ thin film was carried out.The prepared films were observed by scanning electron microscopy and energy spectrum detection,and the rationality of the selected process parameters was verified.The Al₂O₃ thin film prepared on stainless steel substrates were annealed at room temperature,and the influence of annealing temperature on the crystal structure was analyzed.The results show that the ?-Al₂O₃ crystal structure appears and the austenite phase disappears at the annealing temperature of 800?.An ?-Al₂O₃ crystal structure and intermetallic compound AlFe appear at an annealing temperature of 1000?.The process of preparing Al₂O₃ insulating film was explored by using the structural requirements of the thin film sensor and the performance requirements of the sensor film.The effects of sputtering target power,O₂ flow rate,working pressure,negative bias voltage and background vacuum on the performance of DC magnetron and RF magnetron deposition thin film were obtained.The preparation process of Al₂O₃ thin film was improved and optimized.The influence of annealing temperature on the crystal structure of Al₂O₃ thin film was obtained by annealing process.