EFFECT OF SLURRY FLOW RATE ON DISHING, EROSION AND METAL LOSS DURING COPPER CMP PROCESS

摘要

The yield of chemical-mechanical planarization is limited by wafer defects such as dishing and erosion. It is crucial to identify the sources that generate these surface defects. In the present research, the effect of slurry flow rate on the generation of dishing, erosion and metal loss during copper CMP process have been investigated. The patterned copper polishing experiments were conducted on the bench top CMP tester mod. CP-4. I-cue 5001 copper slurry and IC-1000 perforated pad with Suba IV sub-pad were used for polishing. Post-CMP wafer surfaces were characterized for dishing, erosion and metal loss at various features of different line widths and different pattern densities. An atomic force microscope integrated into the Universal Nano & Micro Tester (UNMT-1) was used for imaging wide isolated lines for dishing characteristics. Erosion and metal loss data at dense thin and wide features respectively was measured using a surface profiler. The present investigation is aimed at understanding the effect of CMP process parameters on defects.