2008 年 59 巻 9 号 p. 627
We focused on a via of 150μm in depth and 90μm in opening diameter, which is used for the three dimensional stacking of sheet devices in cellular phones.
The optimized additive compositions are SPS : 3, SPRA : 20, Cl- : 70, and LEVA : 5(mg/dm3). Adopting the periodical reverse pulse(PR pulse) of –6(mA/cm2), the via was completely filled with 540min. Then we used two-steps current for the lower side and upper side of the via. For the lower side, PR pulses of –10(mA/cm2) of 270min was applied and for the upper side, a direct current(DC) of –10(mA/cm2) of 60min was applied. Total time of 330min was required. Furthermore, by applying oxygen purge, the via was filled completely with PR pulses of –15(mA/cm2) for 168min and DC of –10(mA/cm2) for 60min. The total time of 228min was required.
The off time of the PR pulse was set as 0min. The via was filled completely with PR pulse of –15(mA/cm2) of 84min(PR pulse off time=0min) and DC of –10(mA/cm2) of 60min. The via was perfectly filled with total time for 144min. Then we measured the potential for two cases : PR pulse off time=200ms and of PR pulse off time=0ms. Almost same acceleration potentials of via bottom both for PR pulse off time=200ms and for PR pulse off time=0ms. Almost same inhibition potential of via outside both for PR pulse of off time=200ms and for that of off time=0ms.