Porous barrier for evenly distributed purge gas in a microenvironment
View Patent ↗An improved system and method for purging a microenvironment to desired levels of relative humidity, oxygen, or particulates through the implementation of a purge gas delivery apparatus and method that provides even distribution of the purging gas within the microenvironment. A substrate container has a tower therein with a fluid flow passageway extending the length of the tower. Apertures with porous media between the aperture and fluid flow passageway regulate the volume and pressure of air discharging at each aperture. Alternatively, the tower may be formed of a porous tubular polymeric material. A sleeve may direct the discharge purge gas in the interior.
1. A system for transporting substrates comprising:
a substrate container having a container portion with an opening for loading/unloading substrates, a door adapted to sealably cover the opening;
a substrate carrying section disposed in the sunstrate container;
an apparatus comprising an inlet tower adapted to be mounted to the container portion for admitting a gaseous working fluid to interior of the container portion for purging the container portion with the gaseous working fluid;
the inlet tower having a length and comprising a porous tubular portion seated in a non porous polymer fitting with an offset portion, the entirety of the gaseous working fluid passing through an upwardly facing opening of the fitting, and an interior flow passageway extending the length of the tower; and
a check valve positioned in the fitting.
2. The system of claim 1 , wherein said inlet tower comprises a porous polymeric material that blocks water from the interior of the tower.
3. An apparatus for transporting substrates comprising:
a substrate transport container having a container body with a wafer loading/unloading opening and a door adapted to sealably cover the opening; and
an apparatus for admitting a gaseous working fluid to an interior of the container body comprising an inlet tower and a bladder portion made from porous filter material, the bladder portion extending a length of the inlet tower, wherein said bladder has one side that is thinner than an opposite side.
4. An apparatus for transporting substrates comprising:
a substrate transport container having a container body with a wafer loading/unloading opening and a door adapted to sealably cover the opening; and
an apparatus for admitting a gaseous working fluid to an interior of the container comprising an inlet tower and a bladder portion made from the porous filter material, the bladder portion extending a length of the inlet tower, wherein said bladder has a length and is open on one side of said elongate bladder, said opening extending at least substantially the length of the elongate bladder.
5. A method of providing equalized purging flow of a gasous fluid along the length of a purge tower in a substrate container, the method comprising providing a purge tower of a porous tubing, the tubing closed at a top end, connecting the bottom end to a purge port including a fitting with an offset portion, connecting the purge port to a purge gas source exterior of the container, passing the entirety of the gaseous fluid through an upwardly facing opening of the fitting into the porous tubing, and providing a pressurization of the purge tower such that flow velocities and volumes near the top of the tower are equal or substantially equal to such flow velocities and volumes near the bottom of the tower.
6. The method of claim 5 wherein the method further provides adjusting the direction of the purge flow utilizing an elongate sleeve with a lengthwise slot, the sleeve conforming to and fitted to the tubing portion.
7. A substrate container comprising:
a substrate container having a container portion with an opening for loading/unloading substrates, a door adapted to sealably cover the opening; the substrate container having
a substrate carrying region in the substrate container and further comprising an inlet tower mounted to the container portion in an interior of the container portion for admitting a gaseous working fluid to the interior of the container portion for purging the container portion with the gaseous working fluid;
the inlet tower having a length and comprising a tubing portion having a pair of ends and formed of porous material, the tubing portion secured to a nonporous polymer fitting entirely at a bottom of the container portion, the fitting having an upwardly facing opening whereby the entirety of the gaseous fluid passes through the upwardly facing opening of the fitting into the tubing portion, the fitting having an offset portion and providing a purge inlet port, the tubular portion having an axial fluid flow passageway connecting to the purge inlet port at a bottom of the container portion for allowing purge gas to flow up the tubing portion and to exit the tubing portion along the length of the tubing portion above the fitting.