Reduction of Si loss and CD control in HDP Dielectric Etch Systems

摘要

When the dielectric contact etch was performed, severe Si loss (>350 A) and CD change at the contact holes had a deleterious effect on the device performance and they also adversely affected chamber matching. To resolve these issues, a thermal model based on the thermodynamics was proposed. Some of the system parameters were systematically investigated based on the model. Also the polymer flux model during etch was proposed to explain the mechanism for Si subloss and the CD change. By adjusting some hardware parameters, the long-lasting problems have been resolved.