SC-1 Clean Improvements for Post STI CMP

摘要

Particles from shallow trench isolation (STI) chemical mechanical polish (CMP) have been significantly reduced by optimizing the post CMP wet clean. Traditional standard clean-1 (NH_4OH, H_2O_2, H_2O), standard clean-2 (HCL, H_2O_2, H_2O) chemical cleans, and integrated dilute hydrofluoric acid etches were evaluated post STI CMP. Pre and post clean on product defect data was used to determine the overall cleaning efficiency of various wet process cleans. SC-1 process time was optimized to provide a high level of particle removal through megasonic cleaning and SC-1 oxide etching. Significant defect reductions were found at in line defect review operations. An increase in wafer final test yield was also determined from the optimized post STI CMP clean improvements.