Preparation And Study Of Transparent ITO Thin Film Strain Gauge

In this paper,a transparent ITO thin film strain gauge is designed,and the preparation,research and selection of sensitive gate thin film,insulation film and strain gauge structure of ITO thin film strain gauge are completed.Compared with the traditional opaque metal film strain gauge,the transparent ITO film strain gauge can carry out micro deformation measurement while ensuring high transmittance and no blind zone on the surface of the tested component.In this paper,ITO with high transmittance,high stability and low resistivity is used as a sensitive gate material for thin film strain gauges.Preparation of ITO sensitive films by magnetron sputtering method,experimental analysis shows that with the sputtering power density increased to 4.16 W/cm2ITO films have a(100)preferred orientation,at the same time,the absorption side also has a blue shift,the band gap of ITO films increased from 3.71 eV to 4.05 eV.When the sputtering power density exceeds 4.16 W/cm2,the resistivity and carrier concentration of ITO films are kept at 4.91×10-4 ?·cm Omega cm and 5.10×1020 cm-3,respectively.At this time,the crystalline state of the ITO film is enhanced,and the ITO grain changes from the equiaxed crystal to the columnar crystal,and the optical and electrical properties are enhanced.SiO2 insulation film is used as insulation layer.Photoresist method is adopted to prepare ITO thin film strain gauge on the stainless steel metal substrate cantilever beam and sensitivity coefficient is tested.The results show that with the increase of sputtering power density of ITO film,the crystalline state of ITO crystal is better,and the sensitivity coefficient of ITO thin film strain gauge is from-4.55 to-5.24.When the sputtering power density is 6.66 W/cm2,the maximum sensitivity coefficient is-5.24.