Effect of Surfactants on Particle Contamination of Silicon Surface in HF Solutions

摘要

The effect of anionic surfactants on particle adhesion in dilute HF and in subsequent DIW rinse baths has been studied. These baths were intentionally contaminated with Si_3N_4 particles. Surfactants were added in the DHF bath, only, but their impact on the particle adhesion in the contaminated subsequent DIW rinse bath was measured as well. It was found that anionic surfactants can effectively reduce particle contamination in these two baths. The effect of surfactant concentration on the contamination level was tested using three different concentrations. TXRF measurements were carried out to identify sulfur containing surfactant residues remaining on the wafer surface after DIW rinsing. Zeta-potentials of the S13N4 particles in 100 ppm surfactant solutions were measured.