氧化劑對銅／鉭電偶於化學–機械拋光下加凡尼行為的影響

Effect of Oxidizer on the Galvanic Behavior of Cu/Ta Coupling during Chemical-Mechanical Polishing

本研究探討於0.01 M Na2SO4＋1 wt% Al2O3研磨液中添加不同氧化劑（H2O2、KIO3和Fe(NO3)3）對銅／鉭電偶加凡尼行為的影響。在靜置及化學-機械拋光（CMP）情況下，量測未偶合之銅、鉭的開路電位及銅／鉭電偶之加凡尼電流，以瞭解氧化劑所扮演的角色。結果顯示：Fe（NO3）3較H2O2和KIO3更能有效的提升鉭的鈍化，並導致銅和鉭之間極性的轉換。本研究亦探討銅／鉭面積比對電偶的加凡尼電流之影響。結果顯示：在添加Fe（NO3）3氧化劑之研磨液中，銅／鉭面積比為5:1時鉭是陽極，而當面積比為1:1時鉭轉換成為陰極。

The effect of oxidizer addition, namely H2O2, KIO3 and Fe(NO3)3, on the galvanic behavior of the Cu/Ta coupling in 0.01 M Na2SO4 + 1 wt% Al2O3 base slurry was studied. Both open circuit potentials (OCPs) of the uncoupled Cu and Ta as well as galvanic current of the Cu/Ta were measured in static and under chemical mechanical polishing (CMP) condition to analyze the roles of these additives. The results showed that Fe(NO3)3 was more effective than H2O2 and KIO3 in promoting the passivation of Ta, which in turn caused the change of polarity between Cu and Ta. The effect of Cu/Ta area ratio on the galvanic behavior of the coupling was also investigated. The results showed that in Fe(NO3)3-containing slurry, Ta was the anode with a Cu/Ta area ratio of 5:1, but became the cathode with an area ratio of 1:1.