苄叉丙酮和明胶对酸性镀锡层的影响

Influences of Benzylidene Acetone and Gelatin on Acid Tin Coating

采用SEM,XRD和赫尔槽等方法研究了苄叉丙酮和明胶对酸性镀锡层形貌、沉积速率和分散能力的影响。当苄叉丙酮的质量浓度较低时,镀层微粒呈柱状,结晶大小极不均匀。随着其质量浓度的增大,镀层形貌向片状转变,且晶粒尺寸显著细化。当明胶的质量浓度较低时,镀层微粒呈片状紧密地吸附在基体表面,导致结晶不太均匀。随着其质量浓度的增大,镀层晶粒进一步细化均匀。随着苄叉丙酮和明胶的质量浓度的增大,镀层沉积速率先增大后减小,适宜的苄叉丙酮和明胶的质量浓度分别为0.01 g/L和1 g/L。在适宜的条件下施镀15 min,所得镀层在(112)晶面择优取向,结晶细致均匀、光滑平整,为半光亮,镀层沉积速率和镀液分散能力分别达到4 341 mg/(dm2.h)和98.08%,可用于印刷线路板酸性镀锡。

The influences of benzylidene acetone and gelatin on the morphology,deposition rate and throwing power of acid tin coating were investigated using SEM,XRD and Hull cell,etc.The grain size of the coating was very uneven and in columnar-type growth when benzylidene acetone concentration was too low.With the increasing of its mass concentration,the grain size was significantly fined and towards flake-type growth.When gelatin mass concentration was too low,flaky coating particles were closely adsorbed on the substrate surface and the crystals were not homogeneous;and the grain size was further fined and even with the increasing of its mass concentration.The deposition rate of the coating increased firstly and decreased afterwards with the increasing of the mass concentration of benzylidene acetone and gelatin.Their proper dosages were 0.01 g/L and 1 g/L respectively.A semi-bright,glossy and even coating could be obtained under appropriate conditions after plating for 15 min and the crystal face was mainly assigned to the（112） crystal face on the deposits.The deposition rate was 4 341 mg/（dm2·h） and the throwing power reached 98.08 %.The process can be used for acid tin plating in PCB production.