Method and apparatus for increased recirculation and filtration in a photoresist dispense system using a liquid empty reservoir

Patent metadata

Field	Value
Publication number	US-10048587-B2
Application number	US-201514713997-A
Country	US
Kind code	B2
Filing date	May 15, 2015
Priority date	May 15, 2014
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

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. An apparatus for dispensing a liquid onto a substrate, 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;
a liquid empty (LE) reservoir comprising an inlet, a first outlet, a second outlet, and a vent port, the LE reservoir inlet in fluidic communication with the filter outlet via a first valve, the vent port comprising a second valve for selectively opening the LE reservoir to a pressure, and the second outlet in fluidic communication with the reservoir via a third valve;
a dosing pump comprising an inlet, a first pump outlet, and a second pump outlet, the pump inlet in fluidic communication with the LE reservoir first outlet, and the second pump outlet in fluidic connection with the filter inlet via a fourth 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 first pump outlet, the dispense nozzle configured to dispense the liquid onto the substrate;
wherein the reservoir, the filter, the LE reservoir, the dosing pump, and the dispense nozzle are arranged so that:
all the liquid that enters the dosing pump through the pump inlet is filtered by the filter before entering the pump inlet;
the liquid that is pumped through the first pump outlet is fed to the dispense nozzle without passing through the filter after leaving the first pump outlet; and
the liquid that is returned to the LE reservoir through the second pump outlet passes through the filter before returning to the LE reservoir.

2. The apparatus of claim 1 , wherein the pressure is substantially equal to atmospheric pressure.

3. The apparatus of claim 1 , further comprising a mixing system disposed between the dosing pump and the dispense nozzle, the mixing system 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; and
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.

4. The apparatus of claim 3 , further comprising:
a flow valve for the solvent supply inlet; and
a flow valve for the process liquid supply inlet;
wherein the flow valves are configured to adjust the ratio of the solvent and the process liquid entering the mixing chamber.

5. The apparatus of claim 3 , wherein the mixing chamber comprises a static mixer or a holding tank and a stirrer.

6. The apparatus of claim 1 , wherein selectively opening the LE reservoir to the pressure causes liquid from the LE reservoir to flow to the dosing pump and reload the dosing pump.

Assignees

• Tokyo Electron Ltd

Inventors

• Carcasi Michael Andrew
• Printz Wallace Paul
• Hooge Joshua Steven

Classifications

• H10P76/2041

  Photolithographic processes · CPC title

• B05B15/20

  Arrangements for agitating the material to be sprayed, e.g. for stirring, mixing or homogenising · 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

• B05C11/1013

  responsive to flow or pressure of liquid or other fluent material (B05C11/101 takes precedence; control of flow in general G05D7/00; control of fluid pressure in general G05D16/00) · CPC title

• B05B12/006

  Pressure or flow rate sensors · CPC title