Abstract: An apparatus is disclosed for coating a semiconductor wafer with polyimide so that excess polyimide is removed from the wafer edge, back side and coating process area and is conveniently drained. A developer, such as dilute TMAH, that mixes with the excess polyimide is injected into a chamber. The soluble mixture of TMAH and excess polymide may then be drained into a bulk drain, obviating the accumulation of excess polymide in the coater cup. The method is implemented through an assembly that includes a coater cup, spin chuck disposed within the coater cup, and a pair of nozzles intruding into the coater cup at a lower portion of the cup. A fist nozzle operates to inject developing fluid onto the back side of the wafer in the cup, and a second nozzle, positioned nearer the center of the cup and the spin chuck, operates to inject rinsing fluid.

Abstract: In a semiconductor device fabrication process, a method of, and apparatus for, coating a semiconductor wafer with polyimide so that excess polyimide is removed from the wafer edge, back side and coating process area and is conveniently drained. The method comprises the injection into the chamber of a developer, such as dilute TMAH, that mixes with the excess polyimide. The soluble mixture of TMAH and excess polyimide may then be drained into a bulk drain, obviating the accumulation of excess polyimide in the coater cup. The method is implemented through an assembly that includes a coater cup, spin chuck disposed within the coater cup, and a pair of nozzles intruding into the coater cup at a lower portion of the cup. A fist nozzle operates to inject developing fluid onto the back side of the wafer in the cup, and a second nozzle, positioned nearer the center of the cup and the spin chuck, operates to inject rinsing fluid.