Method of controlling pressure in a chamber, apparatus for the same, and exposure apparatus

A method of controlling pressure in a chamber, wherein the air in a chamber in which measurement such as laser measurement is conducted is circulated with an external air adjuster to maintain the pressure in the chamber at a set pressure with respect to fluctuations in external atmospheric pressure, comprising the steps of:

• detecting the external atmospheric pressure;
• obtaining a long-term flat pressure value with respect to short time fluctuations of the detected external atmospheric pressure;
• creating a set pressure in the chamber by adding a predetermined pressure to the obtained pressure value;
• and detecting the pressure in the chamber while introducing external air to said external air adjuster so that the pressure in the chamber reaches the set pressure.

A pressure control apparatus for controlling pressure in a chamber comprising:

• an external atmospheric pressure sensor disposed outside the chamber to detect external atmospheric pressure;
• a signal converter connected to the external atmospheric pressure sensor to separate a long period fluctuation portion of atmospheric pressure and a short period fluctuation portion of atmospheric pressure from said atmospheric pressure detected by said external atmospheric pressure sensor;
• and
• a controller connected to the chamber to control the pressure in said chamber based on a pressure value for said long period fluctuation of atmospheric pressure.

A pressure control method for controlling pressure in a chamber comprising the steps:

• detecting atmospheric pressure chamber external to said chamber;
• separating a long period fluctuation portion of atmospheric pressure and a short period fluctuation portion of atmospheric pressure from said detected atmospheric pressure;
• and
• controlling the pressure in said chamber based on a pressure value for said long period fluctuation of atmospheric pressure.

A pressure control apparatus for controlling pressure in a chamber comprising:

• an external atmospheric pressure sensor disposed outside the chamber to detect external atmospheric pressure, said external atmospheric pressure sensor detecting atmospheric pressure which contains a long period fluctuation portion and a short period fluctuation portion;
• and
• a controller that controls pressure in said chamber based on detection results from said external atmospheric pressure sensor, wherein
• said controller is connected to the external atmospheric pressure sensor to control the pressure in said chamber so that said short period fluctuation portion of the atmospheric pressure with respect to said long period fluctuation portion of the atmospheric pressure is removed or suppressed.

A pressure control method for controlling pressure in a chamber comprising the steps of:

• detecting atmospheric pressure external to the chamber;
• computing a long period fluctuation portion of the atmospheric pressure and a short period fluctuation portion of the atmospheric pressure from a detected pressure;
• removing or suppressing said short period fluctuation portion of the atmospheric pressure with respect to said long period fluctuation portion of the atmospheric pressure, and computing a set pressure;
• and
• controlling the pressure in said chamber based on said set pressure.

A chamber comprising:

• a chamber body of which internal pressure is controlled;
• an external atmospheric pressure sensor disposed outside the chamber body to detect external atmospheric pressure, said external atmospheric pressure sensor generating a signal output which contains a long period fluctuation portion of the atmospheric pressure and a short period fluctuation portion of the atmospheric pressure;
• and
• a controller that controls pressure in said chamber body based on the signal output from said external atmospheric pressure sensor, said controller being connected to the external atmospheric pressure sensor to control the pressure in said chamber body so that said short period fluctuation portion of the atmospheric pressure with respect to said long period fluctuation portion of the atmospheric pressure is removed or suppressed.