Exposure apparatus and method for producing device

Abstract

An exposure apparatus exposes a substrate P by locally filling a side of an image plane of a projection optical system PL with a liquid 50 and projecting an image of a pattern onto the substrate P through the liquid 50 and the projection optical system PL. The exposure apparatus includes a recovery unit 20 which recovers the liquid 50 outflowed to the outside of the substrate P. When the exposure process is performed in accordance with the liquid immersion method, the pattern can be transferred accurately while suppressing any environmental change even when the liquid outflows to the outside of the substrate.

Description

CROSS-REFERENCE [0001] This application is a Continuation Application of International Application No. PCT / JP03 / 015666 which was filed on Dec. 8, 2003 claiming the conventional priority of Japanese patent Application Nos. 2002-357958 filed on Dec. 10, 2002 and 2003-296491 filed on Aug. 20, 2003.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to an exposure apparatus for performing the exposure with an image of a pattern projected by a projection optical system in a state in which a space on a side of an image plane of the projection optical system is locally filled with a liquid. The present invention also relates to a method for producing a device by using the exposure apparatus. [0004] 2. Description of the Related Art [0005] Semiconductor devices and liquid crystal display devices are produced with the so-called photolithography technique in which a pattern formed on a mask is transferred onto a photosensitive substrate. The expos...

AI Technical Summary

Benefits of technology

[0009] The present invention has been made taking the foregoing circumstances into consideration, an object of which is to provide an exposure apparatus and an exposure method in which a pattern can be transferred accurately when an exposure process is performed while filling a space between a projection optical system and a substrate with a liquid, and a method for producing a device in which the exposure apparatus is used.

[0014] According to the present invention, even when the liquid outflows to the outside of the substrate, then the outflowed liquid is recovered by the recovery unit without being left to stand. Therefore, the variation of the environment in which the substrate is placed is suppressed. Further, the occurrence of the inconvenience is also suppressed, which would be otherwise caused such that any rust or the like appears on mechanical parts disposed around the substrate stage for supporting the substrate. Therefore, it is possible to accurately transfer the pattern to the substrate, and it is possible to produce a device having a high pattern accuracy.

[0020] According to the present invention, the liquid can be recovered (sucked) without performing the recovery (suction) above the substrate (from above the substrate). Therefore, it is possible to avoid the occurrence of the sound and the vibration during the exposure for the substrate. Further, the liquid, which outflows to the outside of the substrate, is recovered by the recovery unit. Therefore, it is possible to avoid the variation of the environment in which the substrate is placed and the occurrence of any rust or the like on mechanical parts. Therefore, it is possible to accurately form the pattern on the substrate, and it is possible to produce a device having a high pattern accuracy.

[0025] According to the present invention, for example, even when the liquid outflows, and the liquid inflows into the suction port of the suction system, then the liquid is recovered, and the vacuum source, which serves as the source of the suction, is prevented from any inflow of the liquid. Therefore, even when the liquid immersion exposure is performed, the function of the suction system is guaranteed. It is possible to produce a device by reliably exposing the substrate with the highly accurate pattern.

[0029] a recovery unit (20) which recovers the liquid and at least a part of which is provided on the substrate stage. The exposure apparatus of the present invention makes it possible to avoid the variation of the environment in which the substrate is placed and the occurrence of any rust or the like of mechanical parts.

[0034] In the exposure method of the present invention, the liquid is supplied above the substrate, and the liquid is recovered below the position at which the substrate is held when the liquid immersion exposure is performed. Therefore, it is possible to effectively avoid the occurrence of the sound and the vibration during the exposure of the substrate.

Problems solved by technology

If the depth of focus δ is too narrowed, it is difficult to match the substrate surface with respect to the image plane of the projection optical system.

It is feared that the margin is insufficient during the exposure operation.

As a result, it is feared that any desired pattern transfer accuracy cannot be obtained.

Further, an inconvenience also arises, for example, such that any rust appears due to the outflowed fluid on mechanical parts or the like arranged around the substrate stage for supporting the substrate P. It is also conceived that the liquid is prevented from any outflow by omitting the exposure for the edge area E of the substrate P. However, if the pattern is not formed by applying the exposure process to the edge area E as well, another problem arises as follows.

That is, the substrate P as the wafer abuts against the polishing surface of the CMP apparatus in an unbalanced manner, for example, in the CMP (chemical mechanical polishing) process as the downstream step, and it is impossible to perform any satisfactory polishing.

Further, if the outflowed liquid makes inflow into the tube of the vacuum system (suction system), it is also feared that the vacuum pump, which serves as the vacuum source, may be damaged or broken down.

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