Published online by Cambridge University Press: 10 February 2011
The purpose of this paper is to explore the formation of water residues on wafers during drying. To investigate this DI water droplets were intentionally placed on the surface of substrates with various wettabilities and then left to dry in both N2 and O2 atmospheres. It was found that both hydrophobic and hydrophilic surfaces created the water mark in N2 and O2. The size and dry time of residues were dependent on the wettability of surfaces. Auger analysis of residues showed that the oxidation of surface in water might be one of causes of water mark formation. Considering the pore size of final filters in DI water generation is 0.05 μn, a large number of particles less than 0.05 μm ay be in DI water. In order to investigate the effect of small particles less than 0.05 μm on water mark formation, PSL particles less than 0.05 μm were added to DI water. DI water containing particles was left to dry as a function of particle concentrations. The size of water marks was dependent on the concentration of particles in DI water after they reached a critical concentration.