Coating method, computer storage medium and coating apparatus

Patent metadata

Field	Value
Publication number	US-2016167079-A1
Application number	US-201514963802-A
Country	US
Kind code	A1
Filing date	Dec 9, 2015
Priority date	Dec 11, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

There is provided a coating method which can apply a coating solution uniformly onto a substrate surface while reducing the amount of the coating solution supplied. The coating method for applying a coating solution onto a wafer includes the steps of: supplying a solvent for the coating solution onto the wafer to form an annular liquid film of the solvent in a peripheral area of the wafer; supplying the coating solution to the center of the wafer while rotating the wafer at a first rotational speed (time t 1 -t 2 ); and allowing the coating solution to spread on the wafer by rotating the wafer at a second rotational speed which is higher than the first rotational speed (time t 4 -t 5 ). The supply of the solvent is continued until just before the coating solution comes into contact with the liquid film of the solvent (time t 0 -t 3 ).

First claim

What is claimed is:

1 . A coating method for applying a coating solution onto a substrate, comprising the steps of:
a solvent liquid film forming step of supplying a solvent for the coating solution onto the substrate to form an annular liquid film of the solvent in a peripheral area of the substrate; a coating solution supply step of supplying the coating solution to the center of the substrate while rotating the substrate at a first rotational speed; and a coating solution spreading step of allowing the coating solution to spread on the substrate by rotating the substrate at a second rotational speed which is higher than the first rotational speed, wherein the supply of the solvent is continued until just before the coating solution comes into contact with the liquid film of the solvent in the solvent liquid film forming step or the coating solution spreading step.

2 . The coating method according to claim 1 , wherein in the solvent liquid film forming step, the annular liquid film of the solvent is formed by supplying the solvent from a solvent supply nozzle, positioned above a peripheral portion of the substrate, while rotating the substrate at a rotational speed of more than 0 rpm and not more than the first rotational speed.

3 . The coating method according to claim 1 , wherein in the solvent liquid film forming step, the annular liquid film of the solvent is formed by supplying the solvent from a solvent supply nozzle, which is moving along a peripheral portion of the substrate, while keeping the substrate stationary or rotating the substrate at a rotational speed of more than 0 rpm and not more than the first rotational speed.

4 . The coating method according to claim 3 , wherein the solvent supply nozzle includes a plural number of nozzles.

5 . The coating method according to claim 2 , wherein before the start of the coating solution spreading step, a gap is secured between the liquid film of the solvent and the coating solution by blowing a dry gas onto a position between the solvent supply nozzle and the center of the substrate in a plan view.

6 . The coating method according to claim 2 , wherein in the solvent liquid film forming step, the solvent is supplied from the solvent supply nozzle to a position at a radial distance of about 30 mm to 100 mm from the center of the substrate.

7 . The coating method according to claim 1 , wherein the supply of the solvent is continued until the distance between the outer peripheral and of the coating solution and the inner peripheral end of the annular liquid film of the solvent becomes 5 mm to 60 mm.

8 . The coating method according to claim 1 , wherein in the solvent liquid film forming step, the annular liquid film of the solvent is formed by supplying the solvent to the center of the substrate to form a puddle of the solvent, subsequently rotating the substrate to allow the solvent to diffuse on the substrate, thereby forming a liquid film of the solvent on the entire surface of the substrate, and then blowing a dry gas onto the center of the substrate to remove the liquid film of the solvent from a central portion of the substrate.

9 . The coating method according to claim 1 , wherein prior to the solvent liquid film forming step, a pre-wetting step is performed by supplying the solvent from the solvent supply nozzle, positioned above a peripheral portion of the substrate, to the peripheral portion while rotating the substrate at a rotational speed of more than 0 rpm and not more than the first rotational speed, and then allowing the solvent to spread to the periphery of the substrate by increasing the rotational speed of the substrate from the first rotational speed.

10 . The coating method according to claim 9 , wherein in the pre-wetting step, the supply of the solvent from the solvent supply nozzle is stopped during the period when the solvent is allowed to spread to the periphery of the substrate.

11 . A computer-readable storage medium storing a program that operates on a computer as a controller for controlling a coating apparatus so that it performs the coating method according to claim 1 .

12 . A coating apparatus for applying a coating solution onto a substrate, comprising:
a substrate holder for holding and rotating the substrate; a coating solution supply nozzle for supplying the coating solution onto the substrate; a solvent supply nozzle for supplying a solvent for the coating solution onto the substrate; a first movement mechanism for moving the coating solution supply nozzle; a second movement mechanism for moving the solvent supply nozzle; and a controller configured to control the substrate holder, the coating solution supply nozzle, the solvent supply nozzle, the first movement mechanism and the second movement mechanism so that they perform a method comprising the steps of: supplying the solvent for the coating solution onto the substrate to form an annular liquid film of the solvent in a peripheral area of the substrate; supplying the coating solution to the center of the substrate while rotating the substrate at a first rotational speed; and allowing the coating solution to spread on the substrate by rotating the substrate at a second rotational speed which is higher than the first rotational speed.

13 . The coating apparatus according to claim 12 , further comprising a dry gas nozzle for blowing a dry gas onto the substrate, and a third movement mechanism for moving the dry gas nozzle.

14 . The coating apparatus according to claim 12 , further comprising a support section to which the solvent supply nozzle is mounted and which is configured to be rotatable above the substrate on a vertical axis passing through the center of the substrate as the axis of rotation, and a rotary drive mechanism for rotating the support section, wherein the annular liquid film of the solvent is formed in a peripheral area of the substrate by supplying the solvent from the solvent supply nozzle while rotating the support section by means of the rotary drive mechanism.

Assignees

• Tokyo Electron Ltd

Inventors

• Hasimoto Takafumi
• Hatakeyama Shinichi
• Shibata Naoki
• Yoshihara Kousuke
• Kubota Minoru
• Ide Hiroyuki

Classifications

• H10P72/0448 Primary

  Apparatus for applying a liquid, a resin, an ink or the like · CPC title

• B05D3/104

  Pretreatment of other substrates · CPC title

• G03F7/162

  Coating on a rotating support, e.g. using a whirler or a spinner · CPC title

• B05D3/0466

  the gas being a non-reacting gas (B05D3/0406 takes precedence) · CPC title

• B05D3/042

  Directing or stopping the fluid to be coated with air · CPC title