Apparatus and method for wet cleaning wafers without ammonia vapor damage

摘要

An apparatus and a method for cleaning wafers by a wet bench technique without incurring ammonia vapor damages to the wafer surface are provided. The apparatus of a wet cleaning tank consists of a tank body for holding a quantity of a cleaning solution therein; a conduit mounted through and vertical to a bottom wall of the tank body for feeding an ammonia-containing solution into the tank body through an outlet; and a cup-shaped container mounted in an upside-down position over the outlet of the conduit for blocking ammonia vapor generated by the ammonia-containing solution from reaching an upper cavity of the tank body. The method for cleaning wafers may be practiced by first positioning a conduit vertically through and with an outside wall of the conduit sealingly engaging a bottom wall of a liquid tank with an outlet end of the conduit immersed in a cleaning solution in the tank; then mounting a cup-shaped container in an upside-down position over the outlet end of the conduit to collect any ammonia vapors exiting the conduit and preventing the vapor from reaching an upper portion of the tank cavity.