Sony Corporation

Keisuke Tsudaka

Minoru Sugawara

A method of correcting a mask pattern wherein the mask pattern of a photomask used in a photolithography process is made to deform so as to give a transfer image close to a desired design pattern. The method including: an evaluation point arranging step for arranging a plurality of evaluation points along the outer periphery of the desired design pattern, a simulation step for simulating a transfer image obtained at exposure under predetermined transfer conditions using a photomask of a design pattern with evaluation points, a comparison step for comparing for each evaluation point the difference between the simulated transfer image and the design pattern, and a deformation step for deforming the design pattern in accordance with the differences compared for each evaluation point so that the differences become smaller. In the evaluation point arranging step, for example, the evaluation points are arranged at the corners of the desired design pattern and arranging the evaluation points at predetermined intervals at the sides of the pattern.

Method of correcting mask pattern and mask, method of exposure, apparatus thereof, and photomask and semiconductor device using the same

Method of correcting mask pattern and mask, method of exposure,

A method of correction of a mask pattern in which the mask pattern of a photomask to be used in a photolithographic step is deformed so that a transfer image near a desired design pattern is obtained, including an evaluation point arrangement step for arranging a plurality of evaluation points along an outer periphery of the desired design pattern; a simulation step for simulating the transfer image to be obtained where exposure is carried out under predetermined transfer conditions by using a photomask of a design pattern given the evaluation points; a comparison step for comparing a difference between the simulated transfer image and the design pattern for every evaluation point; and a deformation step for deforming the design pattern according to the difference compared for every evaluation point so that the difference becomes smaller and a correction apparatus for the same.

Correction method and correction apparatus of mask pattern

A method of correcting a mask pattern of a photo-mask used in a photo-lithographic process includes deforming the mask pattern to account for distortions in the pattern that will be caused during projection of the pattern by the photo-lithographic equipment so that the pattern image as transferred by the equipment matches a desired design pattern despite the distortions caused by the equipment. The method includes the steps of simulating a transfer image obtained by projecting a mask pattern through the exposure equipment under predetermined transfer conditions; arranging evaluation points on the transfer image; comparing the evaluation points of the simulated transfer image with the desired design pattern; and deforming the initial mask pattern in accordance with the differences between the simulated transfer image and the desired pattern. The method may also include repeating the foregoing steps to decrease the differences between the transfer pattern and the desired pattern. The evaluation points are arranged at corners and at predetermined intervals along the sides of the transfer pattern.

A method of transforming the exposure pattern is provided so as to obtain a transferred image as being closest possible to the object design pattern in a lithography process. The method includes the steps of dividing a visible outline of desired design pattern P into a plurality of edges according to a specified rule, then assigning a plurality of evaluation points H to each of the edges; computing a transferred image of an exposed pattern by simulation; computing a distance between each evaluation point H on each edge E and a position corresponding to each evaluation point H of the transferred image of the exposed pattern; and determining a corrected exposure pattern by inputting the distance to a specified evaluation function to correct the position of each edge E according to the output value of the evaluation function.

Method and apparatus for correcting exposure patterns, and exposure

A apparatus of correction of a mask pattern in which the mask pattern of a photomask to be used in a photolithographic step is deformed so that a transfer image near a desired design pattern is obtained, including an evaluation point system for arranging a plurality of evaluation points along an outer periphery of the desired design pattern; a simulation system for simulating the transfer image to be obtained where exposure is carried out under predetermined transfer conditions by using a photomask of a design pattern given the evaluation points; a comparison system for comparing a difference between the simulated transfer image and the design pattern for every evaluation point; and a deformation system for deforming the design pattern according to the difference compared for every evaluation point so that the difference becomes smaller.

A method of estimation of a resist pattern which calculates a resist pattern formed by projecting a mask pattern on a resist on a wafer by exposure and then developing it, comprised of a step of calculating a 2D light intensity of the exposure light projected on the wafer based on the mask pattern and the exposure conditions, a step of using the light intensities at peripheral positions of any position noted on the 2D plane of the wafer and the distance between the noted position and the peripheral positions as a basis for calculating and cumulatively adding the effect of the light intensities at a plurality of the peripheral positions on the exposure energy at the any noted position, a step of calculating a latent image formation intensity at the any noted position for the 2D plane of the wafer, a step of finding the distribution of the latent image formation intensity in the 2D plane of the wafer, a step of determining a threshold value of the latent image formation intensity corresponding to the amount of exposure and the development conditions, and a step of finding a contour at the threshold value for the distribution of the latent image formation intensity, the pattern defined by the contour being estimated as the resist pattern. Also, a method of exposure based on the same.

Method of estimation of resist pattern and method of exposure based on

A photomask, a method of producing the same, a method of exposing using the same and a method of manufacturing a semiconductor device using the same are disclosed, which permit correlation to be found out with respect to a large number of mask condition parameters, thus permitting optimum condition to be obtained such as to be less aloof from the actual process, permits quantitative grasping of performance, permits reduction of time and cost, and permits effects of mask pattern size fluctuations, etc. into considerations. Either defocus latitude, mask pattern size latitude II and exposure latitude I is combined with pluralities of data in predetermined ranges of the other two latitudes I and II to determine the permissible range of the first-noted latitude III for optimum value determination.

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Kanagawa, Japan

Keisuke Tsudaka