Vertical photoresist developer

Printed circuit board chemical processing system comprising:

• a. inlet chamber;
• b. main chamber including a liquid sump;
• c. rinse chamber;
• d. drying chamber;
• e. outlet chamber;
• f. an endless chain extending through said chambers, and housing means supporting said chambers and for carrying at least one processing cassette;
• g. substantially horizontally positioned fluid dispensing nozzles in said main, rinse, and drying chambers and means for electromechanically controlling the flow of fluid therethrough;
• h. abutting pairs of vertically disposed flexible seal means between said main, rinse, and drying chambers to allow passage of said processing cassette with said board and prevent comingling of fluids used in respective chambers of said system;
• and,
• i. at least one cassette having a plurality of teeth disposed along a lower side thereof for engagement with said driving chain and having a vertical pocket therein for accepting printed circuit boards of variable size and positioning said boards substantially parallel to the path of movement of said chain for movement between said nozzles and processing through each of said chambers, said pocket in said cassette defined by interior opposing edges of an exterior wall of said cassette, and a plurality of cord means extending between exterior walls of said cassette for retaining said board whereby the fluid from said nozzles flows substantially horizontally to impinge against the planar surfaces of said boards.