A bake plate is an essential tool in photolithography, a process used to transfer a pattern onto a substrate or wafer for the fabrication of microelectronic devices. After the substrate is coated with a photosensitive material, it is exposed to light through a patterned mask, and the areas exposed to light are then chemically altered or removed, leaving behind the desired pattern.
The bake plate is used in the post-exposure bake step, where the substrate is heated to a specific temperature for a certain amount of time to drive chemical reactions and stabilize the pattern. The temperature and duration of the bake step depend on the type of photosensitive material and the desired pattern characteristics. The bake plate provides a uniform temperature across the substrate to ensure consistent results.
Bake plates can be designed with various heating methods, including convection, radiant, or hotplate, and can be controlled by a temperature controller to maintain the desired temperature. Some bake plates can also be equipped with a cooling system to quickly reduce the temperature of the substrate after the bake step, which can be important for some applications.