Coating method and coating apparatus
A coating head is constructed of a solvent feed mechanism connected to a forward side in a direction of movement of a coating solution feed mechanism, and a gas jet mechanism connected to a rearward side in the direction of movement. While moving the coating head relative to a substrate, a solvent is supplied onto the substrate from the solvent feed mechanism, then a coating solution is supplied onto a film of the solvent from the coating solution feed mechanism, and finally a gas is jetted to an uneven surface of the coating solution from the gas jet mechanism to smooth a thin film surface of the coating solution.
1. A coating method for forming a thin film of a coating solution on a substrate, comprising:
a coating solution supply step of supplying the coating solution onto the substrate from a coating solution feed mechanism having an arrangement of inkjet nozzles;
a smoothing step of smoothing a thin film surface of the coating solution by jetting a gas from a gas jet mechanism to the coating solution supplied onto the substrate; and
a solvent supply step of supplying a solvent of the coating solution from a solvent feed mechanism onto the substrate before the coating solution supply step;
wherein the coating solution feed mechanism moves in a direction of movement while supplying the coating solution;
the gas jet mechanism jets the gas obliquely forward in the direction of movement while moving integrally with the coating solution feed mechanism, while disposed rearward of the coating solution feed mechanism with respect to the direction of movement; and
the solvent feed mechanism supplies the solvent only obliquely rearward in the direction of movement while moving integrally with the coating solution feed mechanism, the solvent feed mechanism being disposed forward of the coating solution feed mechanism with respect to the direction of movement;
whereby the coating solution feed mechanism supplies the coating solution onto a thin film of the solvent.
2. The method according to claim 1 wherein the smoothing step is executed to jet the gas with temperature and humidity adjusted in order to inhibit drying of the coating solution supplied onto the substrate.
3. The method according to claim 1 wherein the smoothing step is executed to include a vapor of a solvent of the coating solution in the gas.
4. The method according to claim 1 wherein a solvent supply position on the substrate in the solvent supply step, a coating solution supply position on a solvent film on the substrate in the coating solution supply step, and a gas jet position on the coating solution on the substrate in the smoothing step adjoin one another, and supplying of the solvent, supplying of the coating solution, and jetting of the gas are performed simultaneously in parallel.