Investigation of Novel End-point Detection for Ta/Cu CMP

摘要

End-point detection for Cu/Ta-CMP by COF (Coefficient of Friction) was investigated. Monitoring of COF value oscillation frequency by FFT (Fast Fourier Transform) analysis is proposed to be novel method to determine end point for Cu/Ta/SiO{sub}2 damascene interconnects. The changes of oscillation frequency of shear force were affected by contact characteristic between wafer and pad, which depends on substrates and rotation velocity.