【摘要】 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更多还原

【Abstract】 The moisture diffusion in globtop material,globtop coated with SiN x film,globtop coated with silicone and globtop coated with SiN x plus silicone were measured by humidity sensors wire-bonded on FR4 boards in three different temperature/humidity environments.The experimental results were simulated by Finite Element Method and Fick diffusion law.The moisture diffusion coefficients and activated energies were calculated to quantitatively compare various coatings’ moisture resistance.Our experiment and simulation results show that double layered coating with SiNx plus silicone has excellent moisture-resistance because it not only can smooth the steps on PCB but also keep the good moisture-resistance of inorganic films.更多还原