Method and apparatus for treating fluids to reduce microbubbles
View Patent ↗Versions of the invention include methods for reducing microbubbles in liquids treated by heat or mass exchange devices. The exchange devices may be conditioned by having gases in crevices and surfaces displaced by a liquid. The methods can be used to prepare liquids with reduced numbers of microbubbles.
1. An apparatus for reducing microbubbles in a liquid for dispensing on a substrate, comprising:
an exchange device subject to a reduced pressure to remove gas from one or more gas trapping surface features of the exchange device; and
a housing for the exchange device, the housing having a liquid inlet coupled to a reservoir, a liquid outlet, a vent coupled to the reservoir, and a pump operable to direct a liquid to contact with the gas trapping surface features of the exchange device,
wherein said reduced pressure and said contacting reduce an amount of microbubbles in the liquid to a lower amount than in the absence of said contact of the liquid with surface features of the exchange device.
2. The apparatus of claim 1 , further comprising a dispense line connected to the liquid outlet for dispensing the liquid onto the substrate.
3. The apparatus of claim 1 , wherein the substrate comprises copper.
4. The apparatus of claim 1 , further comprising a valve for switching the liquid between the reservoir for recycling and a process dispense point for dispensing.
5. The apparatus of claim 1 , wherein the liquid from the exchange device is dispensed onto the substrate in a lithographic process.
6. The apparatus of claim 1 , further comprising a heat exchanger for conditioning the liquid using temperature prior to dispensing the liquid from the exchange device onto the substrate.
7. The apparatus of claim 1 , further comprising a filtering membrane for removing particulate, gel, or ionic contaminants from the liquid.
8. The apparatus of claim 1 , further comprising a submicron filtering membrane having a 0.05 micron or smaller pore size rated filter.
9. The apparatus of claim 1 , wherein the liquid includes a surfactant.
10. The apparatus of claim 1 , wherein the liquid includes an organic solvent.
11. A method for reducing microbubbles in a liquid for dispensing on a substrate comprising:
subjecting an exchange device to a reduced pressure to remove gas from one or more gas trapping surface features of the exchange device, the exchange device coupled to a housing having a liquid inlet coupled to a reservoir, a liquid outlet, a vent coupled to the reservoir, and a pump; and
subsequent to said subjecting the exchange device to the reduced pressure, directing the liquid, via the pump, through the exchange device, said directing the liquid causing the liquid to contact the gas trapping surface features of the exchange device,
wherein said reduced pressure and said contacting reduce an amount of microbubbles in the liquid to a lower amount than in the absence of said contact of the liquid with surface features of the exchange device.
12. The method of claim 11 , wherein the liquid from the exchange device is dispensed onto the substrate via a dispense line connected to the liquid outlet.
13. The method of claim 11 , wherein the substrate comprises copper.
14. The method of claim 11 , wherein the dispensing is part of a lithographic process.
15. The method of claim 11 , further comprising switching the liquid between the reservoir for recycling and a process dispense point for dispensing.
16. The method of claim 11 , further comprising conditioning the liquid using temperature prior to dispensing the liquid from the exchange device onto the substrate.
17. The method of claim 11 , further comprising removing particulate, gel, or ionic contaminants from the liquid.
18. The method of claim 11 , further comprising directing the liquid through a submicron filtering membrane of the exchange device, the submicron filtering membrane comprising a 0.05 micron or smaller pore size rated filtering membrane.
19. The method of claim 11 , further comprising directing the liquid through a submicron filtering membrane of the exchange device, the submicron filtering membrane comprising a 0.01 micron or smaller pore size rated filtering membrane.
20. The method of claim 11 , wherein the liquid includes an organic solvent or a surfactant.