电流模式对柠檬酸盐体系镀金的影响

针对作为密封层使用的镀金层存在沉积速率低、厚度不均匀的问题，使用自研精密电镀电源，对比直流（DC）、正向单脉冲（FPC）、正向群脉冲（FGPC）、周期换向脉冲（PPRC）对镀金的影响。仿真PPRC一个周期内镀层厚度的变化情况。使用场发射扫描电子显微镜（FESEM）、X射线衍射仪（XRD）和X射线荧光测厚仪分析镀层的表面形貌、结构、沉积速率、厚度均匀性和电流效率。结果表明：仿真中PPRC较FPC可以明显改善镀层的厚度均匀性，电流模式影响镀金层的晶面峰强和电流效率，DC、FPC、FGPC、PPRC镀金层的晶粒尺寸依次减小，镀金层表面的致密性和厚度均匀性提高，脉冲模式下阴极振动可显著提高沉积速率。使用适宜的PPRC参数镀金，可以在较高的沉积速率下获得厚度均匀、致密的镀金层。

Effects of Current Modes on Gold Electrolating in A Citrate System

To solve the problems of low plating rate and uneven thickness of gold coating as the sealing layer, a self-made precision electroplating power supply was used to compare the effects of direct current (DC), forward pulse current (FPC), forward group pulse current (FGPC) and periodic pulse reverse current (PPRC) on the gold plating. The change of the coating thickness in one cycle of the PPRC was simulated. Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and X-ray fluorescence thickness gauge were used to analyze the surface morphology, structure, plating rate, thickness uniformity and current efficiency of the coating. The results show that in the simulation, PPRC can obviously improve the thickness and uniformity of the coating compared with FPC. The current mode affects the peak intensity of crystal plane and the current efficiency. The grain size of gold coatings obtained by DC, FPC, FGPC and PPRC decreases in turn and the surface density and thickness uniformity of the coatings are improved. Cathode vibration under pulse mode can significantly increase the plating rate. With suitable parameters of PPRC, uniform and compact gold coatings can be obtained at higher plating rates.