On-site manufacture of ultra-high-purity hydrochloric acid for semiconductor processing
AssigneeAir Liquide Electronics Chemicals & Services, Inc.
InventorsJoe G. Hoffman, R. Scot Clark
Life of this patent
Estimating the term…
Abstract
Highly purified HCl for use in semiconductor manufacturing is prepared on-site by drawing HCl vapor from a liquid HCl reservoir, and scrubbing the filtered vapor in a low-pH aqueous scrubber.
Claims40
A method for supplying a high-purity HCl reagent to a workstation in a production line for the manufacture of a high-precision electronic component, said method comprising:
- (a) drawing HCl gas from a vapor space above liquid HCl in an HCl-containing reservoir;
- (b) passing said HCl gas through a filtration membrane for removing particles greater than 0.005 micron therefrom;
- (c) passing said HCl gas thus filtered through a scrubber whereby said HCl gas is contacted with an aqueous solution of HCl in deionized water;
- and
- (d) recovering said HCl gas emerging from said scrubber and directing said HCl gas to said workstation.
A method for the preparation of ultra-high-purity HCl, said method comprising:
- (a) drawing HCl gas from a vapor space above liquid HCl in an HCl-containing reservoir;
- (b) passing said HCl gas through a unit whereby said HCl gas is contacted with an aqueous solution of HCl in deionized water;
- and
- (c) recovering a purified HCl gas emerging from said unit.
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity reagents comprising HCl to a semiconductor manufacturing operation, comprising:
- an evaporation source connected to receive a liquid HCl source and to provide a flow of HCl vapor therefrom;
- said flow of HCl vapor being connected to pass through an ionic purifier unit which provides a recirculating volume of high-purity-water, containing a high concentration of hydrochloric acid, in contact with said flow of HCl vapor;
- a generator unit, connected to receive said flow of HCl vapor from said purifier unit and to combine said HCl vapor with an aqueous liquid to produce an ultra-pure aqueous solution comprising HCl;
- and
- a piping connection which routes said aqueous solution to one or more points of use in the semiconductor device fabrication facility.
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity reagents comprising HCl to a semiconductor manufacturing operation, comprising:
- an evaporation source connected to receive a liquid HCl source and to provide a flow of HCl vapor therefrom;
- said flow of HCl vapor being connected to pass through an ionic purifier unit which provides a recirculating volume of high-purity water, containing a high concentration of hydrochloric acid, in contact with said flow of HCl vapor;
- and
- a generator unit, connected to receive said flow of HCl vapor from said purifier and to combine said HCl vapor with an aqueous liquid to produce an ultra-pure aqueous solution comprising HCl;
- whereby said ultra-pure aqueous solution can be used within the semiconductor device fabrication facility without bulk transfer or exposure of liquid surface to ambient.
An on-site subsystem, in a, semiconductor device fabrication facility, for providing ultra-high-purity HCl for use in semiconductor manufacturing operations at said facility, comprising:
- an evaporation source connected to receive a liquid HCl and to provide a flow of HCl vapor therefrom;
- said flow of HCl vapor being connected to pass through an ionic purifier unit which provides a recirculating volume of high-purity water, containing a high concentration of hydrochloric acid, in contact with said flow of HCl vapor;
- and
- a dryer unit, connected to receive said flow of HCl vapor from said purifier unit and to dry said HCl vapor;
- and
- a piping connection which routes said vapor from said dryer unit to one or more points of use in the semiconductor device fabrication facility.
A system for the preparation of ultra-high purity HCl, said system comprising:
- (a) a reservoir of liquid HCl with a vapor space above said liquid;
- (b) a connection for drawing vapor containing HCl gas from said vapor space;
- (c) a filtration membrane adapted to remove particles from vapor thus drawn;
- and
- (d) a gas-liquid interface chamber in which filtered vapor having passed through said filtration membrane is contacted with an aqueous solution of HCl in deionized water, to produce purified HCl gas.
A system for manufacture of high-precision electronic components, said system comprising:
- (a) a production line containing a plurality of workstations arranged to perform various respective steps, on wafers containing semiconductor material, in manufacture of an electronic component, at least one of said workstations using gaseous HCl as a source gas for operation on to said workpiece;
- and
- (b) a purification subunit connected to said at least one of said workstations by piping to supply said gaseous HCl in ultra-high purity form, said subunit comprising:
- (i) a reservoir of liquid HCl with a vapor space above said liquid HCl;
- (ii) a connection for drawing vapor containing HCl gas from said vapor space;
- (iii) a filtration membrane for removing particles from the vapor thus drawn;
- and
- (iv) a scrubber arranged to contact filtered vapor having passed through said filtration membrane with an aqueous solution of HCl in deionized water, the vapor thus scrubbed being purified HCl gas;
- (c) said purification unit being connected to said workstations by piping, to supply said HCl in ultra-high purity form.
A system for the preparation of ultra-high-purity HCl, comprising:
- an evaporation source connected to receive a liquid HCl source and to provide a flow of HCl vapor therefrom;
- said flow of HCl vapor being connected to pass through a unit which provides a recirculating volume of high-purity water, containing a high concentration of hydrochloric acid, in contact with said flow of HCl vapor, to produce a purified HCl gas;
- said unit having an outlet for removing said purified HCl gas emerging from said unit.
Dependencies are inferred from the claim text.