高透光率电磁屏蔽薄膜工艺及应用研究

Research on the Technology and Application of High Transmittance Electromagnetic Shielding Film

摘要: ITO薄膜在光电窗口的电磁屏蔽领域应用广泛，但是在玻璃表面沉积ITO薄膜材料在潮湿环境下玻璃表面的杂质离子会渗入ITO薄膜中，引起ITO薄膜的色斑腐蚀现象，采用SiO₂过渡层的方式，采用真空镀膜沉积系统，在光学玻璃基底表面依次沉积SiO₂和ITO薄膜材料，研究了过渡层和导电膜的沉积温度、沉积功率、沉积速率、Ar/O₂流量比等工艺参数对导电性和透光率等性能的影响。通过正交试验优化设计，得出SiO₂过渡层的最佳工艺参数为沉积温度为室温，沉积功率为500 W (RF)，小车移动速率为100 mm/min，Ar/O₂流量比为50:0.5；ITO薄膜的最佳工艺参数为沉积温度为360℃，沉积功率为1450 W (DC)，小车移动速率195 mm/min，Ar/O₂流量比为55:0.5；SiO₂/ITO复合薄膜的可见光透过率为83.1%，电磁屏蔽效能在30 MHz~5 GHz均 ≥ 32 dB。

Abstract: ITO thin films are widely used in the electromagnetic shielding field of optoelectronic windows. However, when ITO thin film materials are deposited on the glass surface in a humid environment, impurity ions on the glass surface can penetrate into the ITO thin film, causing color spot corrosion of the ITO thin film. SiO₂ transition layer is used, and a vacuum coating deposition system is used. SiO₂ and ITO thin film materials are sequentially deposited on the optical glass substrate surface. The effects of process parameters such as deposition temperature, deposition power, deposition rate, and Ar/O₂ flow ratio on the conductivity and transmittance of the transition layer and conductive film were studied. Through orthogonal experimental optimization design, the optimal process parameters for the SiO₂ transition layer were obtained as follows: deposition temperature at room temperature, deposition power at 500 W (RF), the moving speed of the car is 100 mm/min, and Ar/O₂ flow ratio at 50:0.5; The optimal process parameters for ITO thin films are deposition temperature of 360˚C, deposition power of 1450 W (DC), the moving speed of the car is 195 mm/min, and Ar/O₂ flow ratio of 55:0.5; The visible light transmittance of SiO₂/ITO composite film is 83.1%, and the electromagnetic shielding efficiency is ≥ 32 dB between 30 MHz and 5 GHz.