Patent Number: 
Section: claims

1. A method of transferring a pattern of a reticle onto a substrate, the method comprising:setting a target pattern to be formed on the substrate using the reticle;obtaining a first pattern transferred onto a substrate by exposure using the reticle and a first illumination condition;calculating, a virtual second illumination condition under which the target pattern is transferred onto a substrate using the reticle, and a virtual third illumination condition under which the first pattern is transferred onto a substrate using the reticle, using mathematical models each of which defines a relationship between an illumination condition and a virtual pattern transferred onto a substrate using the illumination condition;determining a fourth illumination condition, obtained by adding a difference between the calculated second illumination condition and third illumination condition to the first illumination condition, as an illumination condition under which the target pattern is transferred onto a substrate using the reticle; andtransferring the pattern of the reticle onto the substrate by illuminating the reticle using the determined illumination condition. 2. The method according to claim 1, whereinin the calculating, the second illumination condition, which allows at least one of an exposure amount and a defocus amount to have a wide range in which a deviation from a contour of the target pattern falls within an allowable range, is calculated. 3. The method according to claim 1, whereinin the setting, a plurality of target patterns having different focus conditions are set,in the obtaining, a plurality of first patterns are obtained under a plurality of focus conditions,in the calculating, the second and third illumination conditions are calculated for each of the plurality of focus conditions, andin the determinating, an illumination condition, under which the target pattern is transferred onto a substrate using the reticle, is determined based on a plurality of fourth illumination conditions respectively corresponding to the plurality of focus conditions. 4. A method of transferring a pattern of a reticle onto a substrate, the method comprising:setting a target pattern to be formed on a substrate using the reticle;obtaining a first pattern transferred onto a substrate by exposure using the reticle and a first illumination condition;calculating, a virtual second pattern transferred onto a substrate by exposure using the reticle and the first illumination condition, using a mathematical model which defines a relationship between an illumination condition and a virtual pattern transferred onto a substrate using the illumination condition;calculating, using the model, a virtual fifth illumination condition under which a virtual third pattern obtained by adding a difference between the target pattern and the first pattern to the calculated second pattern is transferred onto a substrate by exposure using the reticle;determining the calculated fifth illumination condition as an illumination condition under which the target pattern is transferred onto a substrate using the reticle; andtransferring the pattern of the reticle onto the substrate by illuminating the reticle using the determined illumination condition. 5. The method according to claim 4, whereinin the calculating, the fifth illumination condition, which allows at least one of an exposure amount and a defocus amount to have a wide range in which a deviation from a contour of the target pattern falls within an allowable range, is calculated. 6. The method according to claim 4, whereinin the setting, a plurality of target patterns having different focus conditions are set,in the obtaining, a plurality of first patterns are obtained under the plurality of focus conditions,in the calculating, the fifth illumination condition is calculated for each of the plurality of focus conditions, andin the determining, an illumination condition under which the target pattern is transferred onto a substrate using the reticle is determined based on the plurality of fifth illumination conditions respectively corresponding to the plurality of focus conditions. 7. A computer readable storage medium storing a computer-executable program causing a computer to perform a method comprising:setting a target pattern to be formed on a substrate using the reticle;obtaining a first pattern on a substrate using the reticle and a first illumination condition;calculating, a second illumination condition under which the target pattern is transferred onto a substrate using the reticle, and a third illumination condition under which the first pattern is transferred onto a substrate using the reticle, using mathematical models each of which defines a relationship between an illumination condition and a virtual pattern transferred onto a substrate using the illumination condition; anddetermining a fourth illumination condition, obtained by adding a difference between the calculated second illumination condition and third illumination condition to the first illumination condition, as an illumination condition under which the target pattern is transferred onto a substrate using the reticle. 8. A computer readable storage medium storing a computer-executable program of instructions for causing a computer to perform a method comprising:setting a target pattern to be formed on a substrate using the reticle;obtaining a first pattern on a substrate using the reticle and a first illumination condition;calculating, a virtual second pattern transferred onto a substrate using the reticle and the first illumination condition, using a mathematical model which defines a relationship between an illumination condition and a virtual pattern transferred onto a substrate using the illumination condition;calculating, using the model, a fifth illumination condition under which a virtual third pattern obtained by adding a difference between the target pattern and the first pattern to the calculated second pattern is transferred onto a substrate using the reticle; anddetermining the calculated fifth illumination condition as an illumination condition under which the target pattern is transferred onto a substrate using the reticle. 9. A method comprising:determining an illumination condition of a reticle;exposing a substrate while illuminating the reticle under the determined illumination condition;developing the exposed substrate; andprocessing the developed substrate to manufacture a device,whereinthe determining includessetting a target pattern to be formed on a substrate using the reticle,obtaining a first pattern transferred onto a substrate using the reticle and a first illumination condition,calculating, a second illumination condition under which the target pattern is transferred onto a substrate using the reticle, and a third illumination condition under which the first pattern is transferred onto a substrate using the reticle, using mathematical models each of which defines a relationship between an illumination condition and a virtual pattern transferred onto a substrate using the illumination condition, anddetermining a fourth illumination condition, obtained by adding a difference between the calculated second illumination condition and third illumination condition to the first illumination condition, as an illumination condition under which the target pattern is transferred onto a substrate using the reticle. 10. A method comprising:determining an illumination condition of a reticle;exposing a substrate while illuminating the reticle under the determined illumination condition;developing the exposed substrate; andprocessing the developed substrate to manufacture a device,whereinthe determining includessetting a target pattern to be formed on a substrate using the reticle,obtaining a first pattern transferred onto a substrate using the reticle and a first illumination condition,calculating, a virtual second pattern transferred onto a substrate using the reticle and the first illumination condition, using a mathematical model which defines a relationship between an illumination condition and a virtual pattern transferred onto a substrate using the illumination condition,calculating, using the model, a fifth illumination condition under which a virtual third pattern obtained by adding a difference between the target pattern and the first pattern to the calculated second pattern is transferred onto a substrate using the reticle, anddetermining the calculated fifth illumination condition as an illumination condition under which the target pattern is transferred onto a substrate using the reticle.