21708 In-situ評価手法によるCMPスラリーおよび後処理液とCuとの表面反応の電気化学的評価(配線2,OS.12 機械工学が支援する微細加工技術(半導体・MEMS・NEMS))

抄録

In-situ potentiodaynamic polarization and open circuit potential evaluation were performed for copper in CMP chemicals. Electrochemical reaction is markedly dependent on CMP chemicals, such as oxidizer, inhibitor, and chelate agents. This is due to the difference in surface chemical reactions (anodic and cathodic) and the formation of surface passivation layer. Low density passivation layer evaluated from AFM force curve grows on copper surface in H2O2 oxidizer. In APS oxidizer, there is no passivation layer on copper. The suppression of anodic reaction in polarization and distinct changes in open circuit potential are clearly observed in BTA inhibitor. This means BTA molecules adsorbs on copper immediately and forms passivation layer, however this layer is not dense. More denser passivation layer grows in chelate agents, such as quinaldic acid and glycine.