Coating apparatus, coating method and coating-film forming appratus
A coating apparatus comprises a tray, a nozzle for supplying a coating liquid, and a squeegee which serves as an applicator for spreading a coating liquid. The tray has a recessed portion into which a substrate is placed, and a spinner chuck is provided in the recessed portion. In the spinner chuck, a chuck for attracting the substrate is attached to the upper end of a spinner shaft which can be lifted and lowered, and the upper surface of the chuck and the bottom surface of the recessed portion are arranged to be in the same plane in a state where the spinner shaft is lowered to the lowest position. The nozzle is positioned above a non-recessed portion of the tray and supplies a coating liquid only onto a non-recessed portion of the upper surface of the tray to form a coating liquid pool, and the applicator is relatively movable in a horizontal direction in a state of maintaining a certain distance with respect to the upper surface of the substrate accommodated into the recessed portion and spreads the coating liquid of the coating liquid pool from the non-recessed portion of the upper surface of the tray over the entire upper surface of the substrate.
1. A coating apparatus comprising:
a rotatable tray having a recessed portion for accommodating a substrate and rotatable together with the substrate;
a nozzle which supplies all of a coating liquid for coating the substrate; and
an applicator for spreading the coating liquid,
wherein the recessed portion has a depth which is substantially the same as a thickness of the substrate so that an upper surface of a substrate and an upper surface of the tray will be in the same plane when the substrate is accommodated into the recessed portion and the recessed portion has a similar shape to the substrate, the nozzle for supplying a coating liquid is a tubular member with a discharge opening at a lower end thereof and is positionable above a non-recessed portion of the tray such that the nozzle supplies a coating liquid only onto a non-recessed portion of the upper surface of the tray to form a coating liquid pool on the non-recessed portion of the tray, and the applicator is relatively movable in a horizontal direction in a state of maintaining a certain distance with respect to the upper surface of the substrate accommodated into the recessed portion and spreads the coating liquid of the coating liquid pool from the non-recessed portion of the upper surface of the tray over the entire upper surface of the substrate.
2. The coating apparatus according to claim 1 , wherein the applicator is a squeegee or a roller and is moved linearly in a direction parallel to a surface of the substrate when the substrate is in the recessed portion.
3. The coating apparatus according to claim 1 , further comprising a spinner chuck which can be lifted and lowered, and is provided in the recessed portion of the tray.
4. The coating apparatus according to claim 1 , wherein the applicator is a squeegee having an arc shape when viewed in plan.
5. The coating apparatus according to claim 1 , wherein the nozzle forms the coating liquid pool to have an arc shape or a linear shape adjacent a portion of the substrate at an upstream side of the substrate with respect the moving direction of the applicator as a reference by at least one of rotating the tray by a predetermined angle and moving the nozzle.
6. The coating apparatus according to claim 1 , wherein the recessed portion of the tray has a size and shape which are substantially the same as those of the substrate such that, when the substrate is placed in the recessed portion, the substrate substantially completely fills the recessed portion when viewed in plan.
7. The coating apparatus according to claim 1 , wherein the coating liquid pool on the non-recessed portion of the tray has a sufficient volume so that the applicator spreads the liquid over the entire surface of the substrate at a uniform thickness.
8. The coating apparatus according to claim 1 , wherein at least one of the rotatable tray and the nozzle is moved relative to the other while the nozzle supplies the coating liquid to form the coating liquid pool.
9. The coating apparatus according to claim 1 , wherein after the coating liquid pool has been fully formed the applicator spreads the coating liquid of the coating liquid pool from the non-recessed portion of the upper surface of the tray over the entire upper surface of the substrate.