Method and apparatus for a mechanical dryer for drying thick polymer layers on a substrate

A method for drying a layer of polymer-solvent solution on a substrate comprising the steps of:

• supplying a gas to a plurality of different portions of the substrate moving in a travel direction, the gas forming a temperature zone;
• selectively heating the gas so that the temperature of each temperature zone increases substantially continuously along the travel direction of the substrate;
• and
• controlling the temperature of the gas within each temperature zone to avoid defect formation in the drying of the layer of polymer-solvent solution.

A method using a drying apparatus for drying a layer of polymer-solvent solution on a substrate comprising the steps of:

• conducting, with at least one manifold, a gas across the length of the drying apparatus;
• positioning a plurality of heating elements in the at least one manifold to adjust the temperature of the gas;
• directing, with a plurality of nozzles attached to the at least one manifold, the gas onto the substrate;
• supplying radiant heat to a plurality of different portions of the substrate moving in a travel direction, the radiant heat forming a temperature zone, each temperature zone having a higher temperature than a preceding temperature zone along the travel direction of the substrate;
• and
• controlling the temperature within each temperature zone to avoid defect formation in the drying of the thick layer of polymer-solvent solution.