Laminar gas flow filter

A laminar gas flow filter apparatus for supporting environmental control in a semiconductor wafer processing space, said apparatus comprising:

• a first diffuser tube through which a gas is flowed in a first direction, thereby generating a first flow of gas laterally from the first direction through a sidewall of the first diffuser tube;
• a second diffuser tube through which a gas is flowed in a second direction, thereby generating a second flow of gas laterally from the second direction through a sidewall of the second diffuser tube, said second direction being opposite the first direction;
• a housing containing the first and second diffuser tubes, said first and second flows of gas being combined within the housing and output from the housing to produce a laminar gas flow covering an opening to the semiconductor wafer processing space;
• a first diffuser head and a first gas inlet connected to opposite ends of the first diffuser tube, said first diffuser head capping the first diffuser tube at the end thereof to which the first diffuser head is connected and the first gas inlet supplying a flow of gas under pressure to the first diffuser tube at the end thereof to which the first gas inlet is connected;
• and
• a second diffuser head and a second gas inlet connected to opposite ends of the second diffuser tube, said second diffuser head capping the second diffuser tube at the end thereof to which the second diffuser head is connected and the second gas inlet supplying a flow of gas under pressure to the second diffuser tube at the end thereof to which the second gas inlet is connected.

An apparatus for producing a laminar flow of gas, said apparatus comprising:

• a first diffuser tube having a gas permeable sidewall;
• a first gas inlet which supplies a flow of gas under pressure to a first end of the first diffuser tube such that a first lateral flow of gas is output through the sidewall of the first diffuser tube;
• a first diffuser head which caps a second end of the first diffuser tube, said second end of the first diffuser tube being opposite the first end of the first diffuser tube;
• a housing containing the first diffuser tube;
• and
• a filter through which an output gas flow of the apparatus exits the housing, the output gas flow being generated at least in part due to the first lateral flow of gas.