- Problem Description：Due to the high Tg and low CTE of high-frequency CCL, the plugged via material needs to be matched with low CTE resin, because the reliability of POFV cap copper is mainly affected by CTE matching;

- Solution：The adoption of low CTE modified epoxy resin can achieve high heat resistance and low CTE performance, reduce expansion and contraction at high temperature and keep the same CTE performance with the CCL which can solve the reliability problem of POFV after IR Reflow.

Had been adopted in mass production by PCB manufacturers.