Process for treatment of substrates with water vapor or steam
View Patent ↗A method of treating a substrate comprises, in one aspect, placing a substrate having material on a surface thereof in a treatment chamber; directing a stream of a liquid treatment composition to impinge the substrate surface; and directing a stream of water vapor to impinge the substrate surface and/or to impinge the liquid treatment composition. A preferred aspect of this invention is the removal of materials, and preferably photoresist, from a substrate, wherein the treatment composition is a liquid sulfuric acid composition comprising sulfuric acid and/or its desiccating species and precursors.
1. A method of treating a substrate, comprising
a) placing a substrate having material on a surface thereof in a treatment chamber;
b) directing a stream of a liquid treatment composition comprising sulfuric acid and/or its desiccating species and precursors to impinge the substrate surface; and
c) directing a stream of water vapor to impinge the substrate surface and/or to impinge the liquid treatment composition, wherein the stream of liquid treatment composition and the stream of water vapor originate from separate orifices and at least partially externally intersect prior to impinging the surface of the substrate in an amount effective to increase the temperature of the liquid treatment composition above the temperature of the liquid treatment composition prior to exposure to the water vapor, forming liquid aerosol droplets.
2. The method of claim 1 , wherein the water vapor is provided at a temperature of at least about 100° C.
3. The method of claim 1 , wherein the water vapor is provided at a temperature of about 130° C.
4. The method of claim 1 , wherein the stream of liquid treatment composition and the stream of water vapor at least partially intersect on the surface of the substrate.
5. The method of claim 1 , wherein the stream of water vapor impinges the stream of liquid treatment composition before the stream of liquid treatment composition impinges the substrate.
6. The method of claim 5 , wherein the stream of liquid treatment composition and the stream of water vapor are dispensed from a nozzle construction comprising at least two orifices, the nozzle construction delivering a first stream of liquid treatment composition and a second stream of water vapor in a manner to atomize the liquid treatment composition before the liquid treatment composition impinges the substrate.
7. The method of claim 5 , wherein the stream of liquid treatment composition and the stream of water vapor are dispensed from a nozzle construction comprising three orifices, the nozzle construction delivering a first stream of water vapor from a central orifice, and a second stream and third stream of liquid treatment composition from second and third opposing orifices in a manner to atomize the liquid treatment composition before the liquid treatment composition impinges the substrate.
8. The method of claim 1 , wherein the substrate is rotating, and the stream of liquid treatment composition impinges the substrate at a point ahead of the point where the stream of water vapor impinges the substrate, relative to the rotational direction of the rotating substrate.
9. The method of claim 1 , wherein the substrate is rotating, and the stream of water vapor impinges the substrate at a point ahead of the point where the stream of liquid treatment composition impinges the substrate, relative to the rotational direction of the rotating substrate.
10. The method of claim 1 , wherein the liquid treatment composition at the time of exposure to water vapor has a water/sulfuric acid molar ratio of no greater than about 5:1.
11. The method of claim 10 , wherein the liquid treatment composition is exposed to the water vapor in an amount effective to increase the temperature of the liquid treatment composition above the temperature of both the liquid treatment composition and the water vapor prior to exposure to the water vapor.
12. The method of claim 1 , wherein the stream of water vapor comprises an oxidizing agent.
13. The method of claim 12 , wherein the oxidizing agent is hydrogen peroxide.
14. The method of claim 12 , wherein the oxidizing agent is nitric acid.
15. The method of claim 1 , additionally comprising introducing water vapor and/or nitrogen gas into the treatment chamber to envelop the substrate with water vapor and/or nitrogen gas during the treatment steps b) and c).
16. The method of claim 15 , wherein water vapor is introduced into the treatment chamber to envelop the substrate with water vapor during the treatment steps b) and c).
17. The method of claim 15 , wherein substantially all of the gas present in the treatment chamber is nitrogen gas.
18. The method of claim 15 , wherein substantially all of the gas present in the treatment chamber is water vapor-containing nitrogen gas.
19. The method of claim 16 , wherein the water vapor of the envelopment is introduced so that it is exposed to the substrate at a water vapor temperature of from about 100° C. to about 150° C.