Coating treatment method, computer storage medium, and coating treatment apparatus

A coating treatment method of applying a coating solution onto a substrate, comprising:

• a solvent liquid film formation step of forming a liquid film of a solvent at a middle portion of the substrate and forming a ring-shaped liquid film at an outer peripheral portion of the substrate by forming a liquid film of the solvent by supplying the solvent to the middle portion of the substrate and thereafter rotating the substrate at a predetermined rotation speed to shake off the solvent, and then spraying a dry gas to a position deviated from the middle portion of the substrate with the substrate being rotated to remove the solvent at the position deviated from the middle portion of the substrate;
• a coating solution supply step of supplying the coating solution to a center portion of the substrate while rotating the substrate at a first rotation speed;
• and
• a coating solution diffusion step of diffusing the coating solution on the substrate by rotating the substrate at a second rotation speed higher than the first rotation speed while supplying the coating solution.

A computer-readable storage medium storing a program running on a computer of a control unit controlling a coating treatment apparatus to cause the coating treatment apparatus to execute a coating treatment method of applying a coating solution onto a substrate,

• coating treatment method comprising:
• a solvent liquid film formation step of forming a first liquid film of a solvent at a middle portion of the substrate and forming a ring-shaped second liquid film having a film thickness larger than a film thickness of the first liquid film of the solvent at an outer peripheral portion of the substrate;
• a coating solution supply step of supplying the coating solution to a center portion of the substrate while rotating the substrate at a first rotation speed;
• and
• a coating solution diffusion step of diffusing the coating solution on the substrate by rotating the substrate at a second rotation speed higher than the first rotation speed while supplying the coating solution.

A coating treatment apparatus for applying a coating solution onto a substrate, comprising:

• a substrate holding unit that holds and rotates the substrate;
• a coating solution supply nozzle that supplies the coating solution onto the substrate;
• a solvent supply nozzle that supplies a solvent onto the substrate;
• a first moving mechanism that moves the coating solution supply nozzle;
• a second moving mechanism that moves the solvent supply nozzle;
• and
• a control unit configured to control the substrate holding unit, the coating solution supply nozzle, the solvent supply nozzle, the first moving mechanism, and the second moving mechanism so as to:
• form a first liquid film of the solvent at a middle portion of the substrate and form a ring-shaped second liquid film having a film thickness larger than a film thickness of the first liquid film of the solvent at an outer peripheral portion of the substrate;
• supply the coating solution to a center portion of the substrate while rotating the substrate at a first rotation speed;
• and
• diffuse the coating solution on the substrate by rotating the substrate at a second rotation speed higher than the first rotation speed while supplying the coating solution.