Optical device, method for cleaning the same, projection aligner, and method of producing the same

An optical device, comprising:

• a supply passage which supplies an inert gas into a barrel with plural optical elements disposed therein;
• a supply inlet connected to the supply passage;
• an exhaust outlet which discharges the inert gas in the barrel;
• and
• a removing member which removes a contaminating material, and which is disposed on an inner wall of the supply passage.

A method for cleaning an optical device for use with an exposure apparatus for irradiating a mask with an illuminating light and transferring a pattern on the mask onto a substrate, wherein the optical device has plural chambers formed between plural optical elements disposed in a barrel, each chamber being provided with a gas supply inlet and a gas discharge outlet for a gas having a lower capability of absorbing the illuminating light;

• and the gas supply inlet and the gas discharge outlet being each provided with an opening-closing valve;
• said method is characterized by the steps of:
• filling the barrel with the gas to a predetermined level of pressure in a state in which the opening-closing valve for the gas supply inlet is opened while the opening-closing valve for the gas discharge outlet is closed;
• allowing a contaminating material attached to a surface of each of the optical elements to become suspended or afloat by irradiation with the illuminating light in a state in which the opening-closing valves of the gas supply inlet and the gas discharge outlet are closed;
• flowing the gas outside and inside the barrel by opening the opening-closing valve of the gas supply inlet and the opening-closing valve of the gas discharge outlet;
• and
• closing the opening-closing valves of the gas supply inlet and the gas discharge outlet.

A projection exposure apparatus that forms a pattern on a mask onto a substrate, comprising:

• an optical device having plural chambers formed between plural optical elements disposed in a barrel, each chamber being provided with a gas supply inlet and a gas discharge outlet for a gas having a lower capability for absorbing a illuminating light, and the gas supply inlet and the gas discharge outlet being each provided with an opening-closing valve;
• wherein:
• the optical device is cleaned by a cleaning method characterized by the steps of:
• filling the barrel with the gas to a predetermined level of pressure in a state in which the opening-closing valve for the gas supply inlet is opened while the opening-closing valve for the gas discharge outlet is closed;
• allowing a contaminating material attached to a surface of each of the optical elements to become suspended or afloat by irradiation with the illuminating light in a state in which the opening-closing valves of the gas supply inlet and the gas discharge outlet are closed;
• flowing the gas outside and inside the barrel by opening the opening-closing valve of the gas supply inlet and the opening-closing valve of the gas discharge outlet;
• and
• closing the opening-closing valves of the gas supply inlet and the gas discharge outlet.

An exposure apparatus which transfers a pattern of a mask onto a substrate, comprising:

• an optical system interposed between a light source of an illuminating beam and the substrate:
• a gas supply device which supplies a gas having a lower capability of absorbing the illuminating beam to at least a portion of the optical system;
• and
• an exhaust device which exhausts the gas from the at least the portion of the optical system prior to a supply of the gas.

An optical device, comprising:

• a barrel with plural optical elements disposed therein;
• a protective filter disposed apart in a predetermined distance with respect to an optical element out of the plural optical elements, which is disposed at least at one end side in the axial direction of the barrel;
• and
• the protective filter is detachably mounted on the barrel.

A method of storing an optical device with plural optical elements disposed;

• wherein:
• the optical device has a barrel with plural optical elements disposed therein;
• the method of storing is characterized by the steps of:
• irradiating a surface of each of the optical elements with a light for removing a contaminating material attached on the surface of each of the optical elements;
• filling the barrel with an inert gas to a predetermined level of pressure after the contaminating material removed from the surface of each of the optical elements has been discharged from the barrel;
• and
• storing the optical device in a state in which the barrel is filled with the inert gas.

A method of manufacturing an exposure apparatus which exposes a substrate with an illuminating beam through a mask, wherein:

• the exposure apparatus has a light passage housing to cover a light passage of the illuminating beam and an opening-closing valve on the housing side connected to a pipe for supplying an inert gas;
• and
• an optical device to be mounted on the light passage housing comprises a barrel having plural optical elements disposed therein and being filled with an inert gas, a gas supply inlet connected to the barrel to supply the inert gas to the inside of the barrel, and a gas discharge outlet connected to the barrel to discharge the inert gas inside the barrel, the gas supply inlet and the gas discharge outlet being provided each with an opening-closing valve;
• said manufacturing method is characterized by the steps of:
• installing the optical device in the light passage housing by opening the light passage housing;
• connecting the pipe to the gas supply inlet;
• opening the opening-closing valve for the gas supply inlet and the opening-closing valve for the gas discharge outlet;
• and
• closing the light passage housing.

An optical device comprising:

• a gas supply passage which supplies an inert gas into a barrel with plural optical elements disposed therein;
• a gas supply inlet connected to the gas supply passage;
• an opening-closing valve which controls a flow rate of the inert gas, which is disposed in the gas supply inlet;
• and
• a filter which removes a contaminating material contained in the inert gas, which is disposed in the gas supply passage between the gas supply inlet and the opening-closing valve.

An exposure apparatus which transfers a pattern on a mask onto a substrate, comprising:

• a barrel with plural optical elements disposed therein;
• a gas supply passage which supplies an inert gas into the barrel;
• a gas supply inlet connected to the gas supply passage;
• an opening-closing valve which controls a flow rate of the inert gas, which is disposed on the gas supply passage;
• and
• a filter which removes a contaminating material contained in the inert gas, which is disposed on the gas supply passage locating between the gas supply inlet and the opening-closing valve.

A method for cleaning an optical device for use with an exposure apparatus which transfers a pattern on a mask onto a substrate by irradiating the mask with an illuminating light, wherein:

• the optical device has plural chambers, each of which is provided with a gas supply inlet connected to a barrel to supply a gas having a lower capability of absorbing the illuminating light and a gas discharge outlet connected to the barrel to discharge the gas, each chamber being formed between plural optical elements disposed in the barrel therein, the gas supply inlet and the gas discharge outlet being each provided with an opening-closing valve;
• the cleaning method is characterized by the steps of:
• allowing a contaminating material attached to a surface of each of the optical elements by irradiating the optical elements with the illuminating light;
• and
• flowing the gas outside and inside the barrel by opening the opening-closing valves of the gas supply inlet and the gas discharge outlet.

A projection exposure apparatus which irradiates a mask with an illuminating light and which transfers a pattern on the mask onto a substrate through a projection optical system;

• comprising:
• an optical device having plural chambers, each of which is provided with a gas supply inlet connected to a barrel to supply a gas having a lower capability of absorbing the illuminating light and a gas discharge outlet connected to the barrel to discharge the gas, each chamber being formed between plural optical elements disposed in the barrel therein, the gas supply inlet and the gas discharge outlet being each provided with an opening-closing valve;
• wherein the optical device is subjected to a cleaning method characterized by the steps of:
• allowing a contaminating material attached to a surface of each of the optical elements by irradiating the optical elements with the illuminating light;
• and
• flowing the gas outside and inside the barrel by opening the opening-closing valves of the gas supply inlet and the gas discharge outlet.

An exposing method for irradiating a mask with an illuminating light and transferring a pattern on the mask onto a substrate through a projection optical system, said method is characterized by the steps of:

• supplying a gas having a lower capability of absorbing the illuminating light to each of plural chambers each being formed between plural optical elements disposed in a barrel;
• floating a contaminating material attached to a surface of each of the plural optical elements by irradiating the plural optical elements with a light for removing the contaminating material in a state in which the gas is supplied;
• flowing the gas outside and inside the barrel for each of the plural chambers;
• filling the plural chambers with the gas after flowing the gas;
• and
• transferring the pattern onto the substrate in a state in which the plural chambers are filled with the gas.