Nikon Corporation

Toshio Tsukakoshi

Masato Hamatani

Koji Kaise

Tsunehito Hayashi

An exposure apparatus for transferring a pattern onto an object via a projection optical system, including a moving body arranged on an image plane side with respect to the projection optical system, a wave-front measuring unit at least a part of which is arranged in the moving body, and which measures wave-front information of the projection optical system, an adjusting unit that adjusts a state of an image of a projected pattern generated on the object via the projection optical system, and a controller that controls the adjusting unit using the wave-front information and Zernike Sensitivity corresponding to exposure conditions of the object.

Specification determining method, projection optical system making method and adjusting method, exposure apparatus and making method thereof, and computer system

When actual measurement data of a wavefront aberration of a projection optical system is input, a main controller calculates a targeted image forming characteristic of the projection optical system based on the data and a Zernike sensitivity table of the image forming characteristic that is made prior to the input. By using the Zernike sensitivity table, the targeted image forming characteristic can be calculated with only one measurement of wavefront aberration. Moreover, parameters that denote a relation between an adjustment of an adjustable specific optical element and a change in the image forming characteristics of the projection optical system is obtained in advance, and are stored in advance in a storage unit. Then, when the measurement data of the image forming characteristic of the projection optical system is input, the main controller calculates a targeted adjustment amount of the specific optical element using a relation expression between the measurement data, the parameters, and the targeted adjustment amount of the specific optical element, and adjusts the specific optical element based on the calculation results.

Image forming characteristics measuring method, image forming characteristics adjusting method, exposure method and apparatus, program and storage medium, and device manufacturing method

A computer system comprises a first computer into which target information that an optical apparatus is to achieve is inputted and a second computer that determines the specification of a projection optical system based on the target information received from the first computer via a communication path with using a wave-front aberration amount, which the projection optical system is to satisfy, as a standard. Therefore, in the process of making the projection optical system, higher-order components of the aberration as well as lower-order components can be simultaneously corrected by adjusting the projection optical system based on the result of measuring the wave-front aberration to satisfy the specification, so that the making process becomes simpler. Furthermore, the target that the exposure apparatus is to achieve is securely achieved due to the projection optical system.

The aberration measurement method can determine an aberration from a width of an image of a pattern line on a resist or from a ratio of light quantities upon measuring an amount of the aberration of the image formed by an optical projection system. This method further can measure an amount of a deviation of a position of the image of the pattern on the resist so that it can solve laborious work otherwise required by conventional technology that uses a complicated microscope such as a scanning-type electronic microscope. Moreover, the aberration can be determined by measuring a pitch width of a whole line-and-space pattern containing wedge-shaped lines or lengths of the wedge-shaped lines. This does not require to learn the absolute position of the image because a difference between the amounts of deviation of the positions of the different pattern images so that no such complicated microscope is not required. In addition, as an error of superimposition of the patterns can be corrected by an image of a comparison pattern, no laborious attention is any longer paid to alignment of the patterns, thereby allowing a measurement of the amount of the aberration with an optical projection system or by other means at a high speed and with high precision.

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Ageo, Japan

Toshio Tsukakoshi