Deposition and electrostatic removal of gaseous organic contaminants on substrate surfaces

The adhesion behavior of di-n-butyl phthalate (DBP) onto different substrates (quartz, glass, and silicon) used as wafer surfaces was studied by using an in situ UV spectrophotometric technique. The results from the closed cell experiments revealed that greatest extent of DBP adhesion occurred on the quartz chip (0.154 μg cm−2), followed in the order by the glass (0.054 μg cm−2) and silicon (0.039 μg cm−2). By means of the in situ spectrophotometric observation, application of an electrical field at 290 V cm−1 in the cell proved to be effective in inducing charging of DBP aerosols, which were consequently attracted towards the electrodes. This method can be applied to wafer storage and transport equipments to prevent wafer contamination from material outgassing representative by DBP.