Patent attributes
In a nozzle unit 4 equipped with processing-liquid nozzles 4A to 4J, an air layer 73 and a solvent layer 74 for processing liquid are successively formed outside a processing-liquid layer 71 included in the tip of each nozzle 4A (4B to 4J). Next, the solvent layer 74 in the nozzle 4A is thrown out into a drain part 62 of a standby unit 6 and subsequently, the processing liquid is supplied from the nozzle 4A to the surface of a wafer W, performing a coating process. After completing the coating process, the processing liquid remaining in the nozzle 4A is sucked and continuously, respective tips of the nozzles 4A to 4J are dipped into respective solvents in solvent reservoir 62A to 62J, respectively. From this state, by sucking in the nozzle 4A, there are newly formed, outside the processing layer 71 in the tip of the nozzle 4A, an air layer 73 and a solvent layer 74. Thus, in supplying a substrate, such as semiconductor wafer, with a processing liquid by use of a nozzle unit having a plurality of processing-liquid nozzles integrated, it is possible to prevent dryness of the processing liquids in the respective nozzles while preventing the nozzle unit from being large-sized.