Electrogenerated chemical polishing (EGCP) is a new, stress-free polishing method. Stress free polishing of workpiece surface is realized by diffusion controlled chemical reaction and etchant is generated by electrochemical reaction on electrode surface. The components of polishing solution are the key factors to realize the diffusion controlled reaction and controllable material removal process. The basic principle of EGCP is analyzed, and the basic characteristics of polishing solution are proposed according to the theoretical analysis. For realizing EGCP of Cu, the FeSO4 (redox mediator), H2SO4 (pH adjusting agent) and BTA (lateral charge propagation inhibitor) are chosen as the polishing solution. Through analyzing the surface components of polished workpiece by XPS and XRD, the action mechanisms of H2SO4 and BTA are studied. The results show that the H2SO4 is benefit to promoting the etching reaction through removing the Cu oxide layer. BTA can be adsorbed on the Cu surface, and then suppresses surface lateral charge propagation.
SHAN Kun
,
ZHOU Ping
,
CAI Jiqing
,
KANG Renke
,
GUO Dongming
. Chemical Components and Its Functions of Polishing Solution Used in Electrogenerated Chemical Polishing of Copper[J]. Journal of Mechanical Engineering, 2016
, 52(5)
: 88
-94
.
DOI: 10.3901/JME.2016.05.088
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