Optical device method of cleaning the same, projection aligner, and method of producing the same
AssigneeNikon Corporation
InventorsMasayuki Akagawa, Osamu Yamashita, Taichi Taniuchi
Life of this patent
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Abstract
An exposure method for irradiating a mask with an illuminating light and transferring a pattern on the mask onto a substrate through a projection optical system includes supplying a gas having a lower capability of absorbing illuminating light to each of plural chambers formed between optical elements disposed in a barrel, floating a contaminating substance on the plural elements in the gas by irradiation, exhausting the gas and contaminating substances from the barrel, supplying the plural chambers with further gas, after exhausting the gas containing the contaminating substance, and transferring the pattern onto the substrate.
Claims14
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 comprising 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 substance attached to a surface of each of the plural optical elements in the gas by irradiating the plural optical elements with a light for removing the contaminating substance in a state in which the gas is supplied;
- exhausting the gas, in which the contaminating substance is floating in each of the chambers, from the barrel;
- supplying each of the plural chambers with further gas after exhausting the gas in which the contaminating substance is floating;
- and
- transferring the pattern onto the substrate.
An exposing method for transferring a pattern formed on a mask onto a substrate with an exposing light emitted from a light source, said method comprising the steps of:
- prior to an exposure operation by which the pattern formed on the mask is transferred onto the substrate,
- supplying an inert gas to spaces each of which is formed between plural optical elements disposed between the light source and the substrate;
- removing a contaminating substance attached to a surface of each of the plural optical elements from the surface by irradiating each of the optical elements with the exposing light;
- exhausting the contaminating substance together with the inert gas from the spaces;
- and
- supplying each of the spaces with further insert gas, thereby resulting in filling the space with the further inert gas.
Dependencies are inferred from the claim text.