测量了在FR4基板上用引线键合和顶充胶封装的湿度传感器在无防护、氮化硅薄膜防护、硅酮涂层防护、硅酮涂层加氮化硅薄膜防护四种情况下及在不同温湿度环境下的水汽扩散曲线。应用有限元分析和FICK扩散方程模拟了实验曲线 ,得到了水汽在各种防护条件下的扩散系数 ,进而计算出水汽扩散的激活能 ,定量比较了各种防护方法的效果。实验和模拟结果表明 :硅酮加氮化硅薄膜的双层防护可以显著改善电子模块的防水性能 Measured in the FR4 substrate with wire bonding and top filled plastic package humidity sensor without protection, silicon nitride film protection, silicone coating protection, silicone coating and silicon nitride film protection in four cases and Vapor diffusion curves under different temperature and humidity. The experimental curves were simulated by finite element analysis and FICK diffusion equation, and the diffusion coefficients of water vapor under various protective conditions were obtained. Then the activation energy of water vapor diffusion was calculated and the effects of various protective methods were quantitatively compared. The experimental and simulation results show that double-layer protection of silicone and silicon nitride films can significantly improve the water resistance of the electronic module