精确阻值的碳膜板制作工艺研究

Research on the production process of conductive carbon paste PCB with high precision resistance

现有碳膜板工艺难以精确控制阻值，如今已被新的埋阻技术所取代，然而较低的制作成本使得碳膜板仍存在一定的市场发展空间。文章通过对碳膜板的阻值变动趋势进行分析，提出对阻焊制作和回流焊处理的工艺流程改进，从而稳定阻值的变化幅度，提升了产品的阻值制作精度和成品良率。

The current technology of conductive carbon paste PCB is difficult to precisely control the resistance, which has now been replaced by the new embedded resistance technology. However, there is still room for the conductive carbon paste PCB market for the reason of lower production costs. In this paper, the resistance changing trend of the conductive carbon paste PCB is analyzed, then it presented the process improvements about solder mask and reflow process. Finally, the amplitude of the resistance cbange is stabilized, and the resistance precision and product yield are improved as well.