Efem and load port

Abstract

There is provided an EFEM that includes a shield gas curtain apparatus 6 that forms a gas curtain capable of shielding an opening 23 when an internal space 5 S of a purge container 5 , in which the humidity is reduced to a predetermined value by means of a bottom purge apparatus 25 provided in a load port 2 , is brought into communication with an internal space 3 S of a wafer transport chamber 3 , the gas curtain being formed of a shield curtain gas blown immediately downward from a location near the opening 23 of the load port 2 and being closer to the wafer transport chamber 3 than the opening 23 at a higher height than an upper edge of the opening 23 . The EFEM thus configured can prevent and suppress a rapid increase in the humidity in the purge container, in which the humidity in the interior space is reduced by performing the bottom purging, occurring immediately after a lid of the purge container is opened, so that quality degradation due to the moisture adhered on a wafer can be avoided.

What is claimed is: 
     
         1 . An EFEM, comprising:
 a wafer transport chamber;   a load port adjacent to the wafer transport chamber; and   a shield gas curtain apparatus,   wherein the load port includes a bottom purge apparatus capable of replacing a gaseous atmosphere in a purge container with a purge gas composed of nitrogen or dry air from the bottom side of the purge container, and   wherein the shield gas curtain apparatus forms a gas curtain capable of shielding an opening of the load port when an internal space of the purge container, in which at least humidity is reduced to a predetermined value by supplying the purge gas from the bottom purge apparatus, is brought into communication with an internal space of the wafer transport chamber through the opening, the gas curtain being formed of a shield curtain gas composed of nitrogen or dry air blown immediately downward or obliquely downward such that the gas diverges from the purge container, from a location near the opening and being closer to the wafer transport chamber than the opening at the same height as or a higher height than an upper edge of the opening.   
     
     
         2 . A load port adjacent to a wafer transport chamber, comprising:
 a bottom purge apparatus; and   a shield gas curtain apparatus,   wherein the bottom purge apparatus is capable of replacing a gaseous atmosphere in a purge container with a purge gas composed of nitrogen or dry air from the bottom side of the purge container, and   wherein the shield gas curtain apparatus forms a gas curtain capable of shielding an opening when an internal space of the purge container, in which at least humidity is reduced to a predetermined value by supplying the purge gas from the bottom purge apparatus, is brought into communication with an internal space of the wafer transport chamber through the opening, the gas curtain being formed of a shield curtain gas composed of nitrogen or dry air blown immediately downward or obliquely downward such that the gas diverges from the purge container, from a location near the opening and being closer to the wafer transport chamber than the opening at the same height as or a higher height than an upper edge of the opening.