Foup opener

A FOUP opener for opening and closing a FOUP door which closes a front opening portion of a FOUP containing a plurality of semiconductor wafers oriented horizontally and arranged in layers at predetermined intervals, said FOUP opener comprising:

• a dock plate for carrying and positioning said FOUP;
• a dock moving mechanism for moving said dock plate to a position for detachment and attachment of said FOUP door;
• a port door including a detachment/attachment mechanism for detaching and attaching said FOUP door and a holder mechanism for holding said FOUP door;
• a port plate including an opening portion, the opening portion being closed by said port door;
• a port door horizontal-movement mechanism for horizontally moving said port door;
• and
• a port door vertical-movement mechanism for vertically moving said port door with said port door holding said FOUP door, so as to house said FOUP door, wherein
• said port door includes a protrusion provided along an outer circumferential edge of said port door in such a manner as to project toward said FOUP door and to abut said FOUP door along an entire circumference of said FOUP door, thereby sealing a space defined between an outside wall of said FOUP door and an outside wall of said port door.