Method and apparatus for multiple recirculation and filtration cycles per dispense in a photoresist dispense system

Patent metadata

Field	Value
Publication number	US-2020348596-A1
Application number	US-202016935674-A
Country	US
Kind code	A1
Filing date	Jul 22, 2020
Priority date	May 15, 2014
Publication date	Nov 5, 2020
Grant date	—

Abstract

An apparatus for dispensing a liquid onto a substrate may comprise a reservoir for storing the liquid to be dispensed; a filter comprising an inlet and an outlet, the filter inlet in fluidic communication with the reservoir via a first valve; a dosing pump comprising an inlet, a first outlet, and a second outlet, the dosing pump inlet in fluidic communication with the reservoir and the dosing pump second outlet in fluidic communication with the filter inlet via a second valve, the dosing pump configured to dose an amount of the liquid and pump the liquid; and a dispense nozzle in fluidic communication with the dosing pump first outlet, the dispense nozzle configured to dispense the liquid onto the substrate..

First claim

What is claimed is:

1 . A method for dispensing a liquid onto a substrate using an apparatus comprising a reservoir for storing the liquid to be dispensed; a filter comprising an inlet and an outlet, the filter inlet in fluidic communication with the reservoir via a first valve; a dosing pump comprising an inlet, a first outlet, and a second outlet, the dosing pump inlet in fluidic communication with the reservoir and the dosing pump second outlet in fluidic communication with the filter inlet via a second valve; and a dispense nozzle in fluidic communication with the dosing pump first outlet; the method comprising:
dispensing the liquid through the dispense nozzle onto the substrate; and alternately flowing the liquid from the dosing pump via the second valve to the filter to filter the liquid while maintaining a positive pressure at the filter inlet and flowing the liquid from the reservoir via the filter and trap reservoir to reload the dosing pump while filtering the liquid; wherein the liquid is alternately flowed from the dosing pump and from the reservoir a plurality of times per dispense.

2 . The method of claim 1 , wherein the apparatus further comprises a mixing system disposed between the dosing pump and the dispense nozzle and comprising a solvent supply inlet in fluidic communication with a solvent supply; a process liquid supply inlet in fluidic communication with the dosing pump outlet; a mixing chamber in fluidic communication with the solvent supply inlet and process liquid supply inlet and configured to mix solvent and process liquid; an outlet in fluidic communication with the mixing chamber and the dispense nozzle and configured to supply the mixed solvent and process liquid to the dispense nozzle; a flow valve for the solvent supply inlet; and a flow valve for the process liquid supply inlet; the method further comprising:
adjusting the ratio of the solvent and the process liquid entering the mixing chamber with the flow valves.

3 . The method of claim 1 , wherein the liquid flowing from the dosing pump has a volume less than or equal to the dosing pump volume.

4 . The method of claim 1 , wherein the liquid flowing from the reservoir has a volume less than or equal to the dosing pump volume.

5 . The method of claim 1 , further comprising:
setting a volume of the liquid flowing from the dosing pump, a volume of the liquid flowing from the reservoir, or a combination thereof in order to maximize an amount of liquid filtered by the filter per dispense based on maximizing a total pressure applied to the filter during a dispense cycle time.

6 . The method of claim 5 , further comprising:
detecting the total pressure based on a difference between a pressure on the inlet side of the filter and a pressure on the outlet side of the filter.

7 . A method for supplying a liquid using an apparatus comprising a main reservoir for storing the liquid; a first liquid empty (LE) reservoir in fluidic communication with the main reservoir; a filter in fluidic communication with the first LE reservoir; a second LE reservoir in fluidic communication with the filter; and a driving system coupled to the first LE reservoir and the second LE reservoir; the method comprising:
alternately filling the first LE reservoir and second LE reservoir with the liquid from the main reservoir using the driving system, wherein the alternate filling of the first LE reservoir and second LE reservoir causes the liquid to be filtered by the filter.

8 . The method of claim 7 , wherein the apparatus further comprises a dosing pump and a dispense nozzle, the method further comprising:
dosing an amount of the liquid and pumping the liquid with the dosing pump; and dispensing the liquid onto a substrate with the dispense nozzle.

9 . The method of claim 7 , wherein the apparatus further comprises a mixing system disposed between the dosing pump and the dispense nozzle and comprising a solvent supply inlet in fluidic communication with a solvent supply; a process liquid supply inlet in fluidic communication with the dosing pump outlet; a mixing chamber in fluidic communication with the solvent supply inlet and process liquid supply inlet and configured to mix solvent and process liquid; an outlet in fluidic communication with the mixing chamber and the dispense nozzle and configured to supply the mixed solvent and process liquid to the dispense nozzle; a flow valve for the solvent supply inlet; and a flow valve for the process liquid supply inlet; the method further comprising:
adjusting the ratio of the solvent and the process liquid entering the mixing chamber with the flow valves.

10 . The method of claim 7 , further comprising:
reloading the dosing pump with the liquid by flowing the liquid from the reservoir, through the filter, the first valve, and the LE reservoir.

11 . The method of claim 7 , wherein a positive pressure is maintained at the filter inlet.

12 . The method of claim 7 , wherein the positive pressure is maintained at the filter inlet by pressurizing the liquid inside the reservoir.

13 . The method of claim 7 , wherein a negative pressure is maintained at the filter inlet.

Assignees

• Tokyo Electron Ltd

Inventors

• Carcasi Michael
• Printz Wallace
• Hooge Joshua

Classifications

• H10P76/2041

  Photolithographic processes · CPC title

• G03F7/162 Primary

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

• B01D37/00

  Processes of filtration (processes specially adapted for filtering gases B01D46/00) · CPC title

• B01D19/0031

  by filtration · CPC title

• B05B7/26

  Apparatus in which liquids or other fluent materials from different sources are brought together before entering the discharge device {(B05B7/2402 takes precedence)} · CPC title