Indexed by:Journal Papers

Date of Publication:2019-11-07

Journal:ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY

Included Journals:EI、SCIE

Volume:8

Issue:11

Page Number:P699-P703

ISSN No.:2162-8769

Abstract:It is difficult to achieve low roughness in a short time with high material removal rate (MRR) at low polishing pressure by conventional CMP of copper. To solve this problem, a two-step electrochemical mechanical polishing (ECMP) method consisting of rough polishing and fine polishing at polishing pressure less than 0.3 psi is proposed. Then potentiodynamic polarization, potentiostatic polarization and ECMP experiments were conducted to verify the feasibility of the combined process. The results of rough polishing show that MRR of more than 1 mu m.min(-1) can be reached with hydroxyethylidene diphosphonic acid (HEDP) based electrolyte. Besides, the roughness can be improved from Ra 610.4 nmto Ra 155.0 nm after 20 min rough polishing. The roughness can be further improved to Ra 4.7 nm after 60 min fine polishing with glycine-benzotriazole (BTA) based electrolyte. The results demonstrated that the two-step ECMP is effective to achieve low surface roughness within a short time. (c) 2019 The Electrochemical Society.