Spraying photoresist is a unique method for obtaining conformal coatings over large topography steps. Special resist formulations are required to speed drying and prevent leveling of the wet film. Film thickness is set by the number of spray passes and imaging is achieved using standard exposure wavelengths and developers. AZ 400K 1:4 developer recommended. AZ 4999 Photoresist is available in 5 Liter HDPE bottles.