Wafer drying apparatus and method

Apparatus for drying a wafer having opposite planar sides, the apparatus comprising:

• a bath for containing a fluid, the fluid defining an upper surface;
• a heat transfer chamber having a plurality of walls, each of the walls having a bottom at generally the same level as the level of a bottom of an adjacent one of the walls, the chamber defining a wafer drying volume extending upwardly from the upper fluid surface and within which a wafer drying path extends, at least one of the walls being provided with a gas inlet positioned spaced from the respective bottom;
• a support for suspending the chamber above the bath with the wafer drying path extending from the gas inlet and extending immediately above the upper fluid surface, the support positioning the bottoms of the chamber walls immediately above the upper fluid surface to define an elongated gas exhaust outlet extending around a portion of the wafer drying path, the support suspending the chamber to define the wafer drying path as extending from immediately above the upper fluid surface to the gas exhaust outlet;
• a hot gas supply connected to the gas inlet to flow hot gas in the wafer drying path downwardly through the chamber across the opposite planar sides of the wafer and out of the chamber through the elongated outlet to continuously transfer thermal energy at a selected temperature across the wafer drying path;
• and
• a heater connected to the chamber between the gas inlet and the elongated gas exhaust outlet for radiating thermal energy across the wafer drying path.

A method for drying a wafer, comprising the operations of:

• introducing a wafer being in a wet state into a fluid bath;
• removing the wafer from the fluid bath at a controlled rate along a selected path;
• and
• applying heated gas to the wafer as the wafer is moved through the upper surface and out of the fluid bath, the applied heated gas being in at least one continuous flow path from above the wafer and to and across the wafer and across the upper surface without recirculating the heated gas to the wafer, the applied heated gas assisting a transition of the wafer to a dry state during the removing operation.

A method for drying a wafer, comprising the operations of:

• immersing a wafer in a fluid bath to wet opposite sides of the wafer with the fluid;
• moving the wafer from the fluid bath into a defined volume, the rate of moving of the wafer being selected to form a meniscus on each of the opposite sides and a thin film of the fluid above the meniscus on the respective opposite sides of the wafer as the wafer moves from the fluid into the defined volume;
• flowing heated gas along the wafer as the wafer is moved along the selected path from of the fluid to assist in the evaporation of the thin film of the fluid from the wafer;
• and
• exhausting from the defined volume the evaporated thin film and the gas.