0前言有些多层板设计的图形存在内层重叠的基材空旷区,在生产过程中经常会出现一些问题,例如:基材空旷区压合后铜皱,外光成像后基材处白斑,阻焊后基材位置白斑,测试内短,物理室可靠性测试空洞。其中问题点最严重的是基材白斑、空洞(图1)。我公司为此问题已经多次被多个客户投诉,物理实验室在进行热冲击验证时也多次发现,现需对此问题进行研究并改善。 0 Preface Some multilayer designs exist in the inner layer of the substrate open area overlap, often in the production process there will be some problems, such as: the substrate open area pressed copper wrinkle, After solder mask substrate location white spot, short test, physical room reliability test hole. One of the most serious problem is the substrate white spot, hollow (Figure 1). Our company has repeatedly been a number of customers for this issue complaints, physics laboratories in the thermal shock verification also found many times, it is necessary to study and improve on this issue.