Photoresist applying device and applying method therefor

#The present invention relates to a photoresist applying device and applying method therefor for applying photoresist onto a semiconductor substrate surface, and more particularly to a photoresist applying device and applying method therefor characterized in a nozzle pipe structure.

#As shown in FIG. 1, the photoresist flow passage provided in the photoresist applying device of prior art is structured by a photoresist bottle 1, a buffer tank 2, a pump 3, a filter 4, an ejection valve 5, a suck-back valve 6, nozzle pipe 7b, and a nozzle tip 8. The parts of from the photoresist bottle 1 to the ejection valve 5 are respectively connected by the pipe 7a.

#At first, in a waiting state of the conventional photoresist applying device, the photoresist stored in the photoresist bottle 1 is previously filled up to a tip end of the nozzle tip 8 through the various parts from the buffer tank 2 to the nozzle pipe 7. When applying photoresist to a semiconductor substrate 100 surface, the photoresist is ejected at the nozzle tip 8 by an ejecting operation of the pump 3 and the simultaneous opening/closing operation of the ejection valve 5. Furthermore, by the immediately after continuing sucking operations of the pump 3, photoresist is sucked from the photoresist bottle 1 into the pump 3, to prepare for the next ejection.

#FIG. 1 is a view for explaining a photoresist applying apparatus and applying method therefor in a prior art;

#FIG. 2 is a view for explaining a photoresist applying apparatus and applying method therefor in a first embodiment of the present invention;

#FIG. 3 is a view for explaining a photoresist applying apparatus and applying method therefor in a second embodiment of the present invention; and

#FIG. 2 is a view for explaining a photoresist applying device and an applying method therefor of a first embodiment of the present invention. The photoresist applying device in the first embodiment of the invention, in its general constituent elements, is similar to the conventional photoresist applying device shown in FIG. 1.

#The photoresist applying device of the first embodiment of the invention is characterized in that an air-bubble collecting part is provided on a photoresist flow passage at its predetermined part of nozzle pipe 7 directly connected to a nozzle tip 8. The nozzle pipe 7 has an external appearance in a shape curved in an inverted U-form (∩). Specifically, the nozzle pipe 7 is structured by a horizontal part A, a rise part B and a fall part C in the order from the suck-back valve 6 side, and structured to provide a nozzle tip 8 at a tip end of the fall part C. By thus structuring the nozzle pipe 7, a curved part 9 is made between the rise and fall parts so that a top dead center 10 in the curved part 9 serves as an air-bubble collecting part. Herein, it is important to design the fall part diameter and length of nozzle pipe 7 to have an interior bulk of pipe capable of securing a photoresist amount greater than the photoresist amount of one projection.

#Meanwhile, the nozzle tip 8 is provided in a position in the above of a substrate 100 mounting part in the photoresist applying device (above a cup part) and in the center of the substrate 100 surface.