Local flare correction
AssigneeFujitsu Microelectronics Limited
InventorsTeruyoshi Yao, Satoru Asai
Life of this patent
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Abstract
A correction of a local flare generated at a time of exposure when manufacturing a semiconductor device, wherein a substantial numerical aperture to a pattern in a region to be exposed is calculated for the each region, after that, the flare correction amount for the pattern in the each region is adjusted in conformity with the substantial numerical aperture and exposure conditions in the each region. Backed by this, the effect of the local flare on the pattern exposed by photolithography can be quantitatively corrected in conformity with the respective exposure conditions, so that a desired pattern can be formed readily and accurately.
Claims20
A flare correction method correcting a local flare generated at a time of exposure when manufacturing a semiconductor device, comprising the steps of:
- calculating an effective numerical aperture to a pattern in a region, for each region to be exposed;
- and
- calculating a correction amount of the flare of the pattern as a size variation ratio based on a relation between the effective numerical aperture and a size variation of the pattern for the each region to be exposed.
A flare correction method correcting a local flare generated at a time of exposure when manufacturing a semiconductor device, comprising the steps of:
- calculating, in each region to be exposed, a point spread function of the flare by using an experimental mask to estimate the flare, on a basis of a measurement result of the experimental mask and in conformity with exposure conditions of the each region;
- and
- calculating, for each region to be exposed, a effective numerical aperture to a pattern in the each region based on a light intensity distribution of the flare;
- and
- calculating a flare correction amount for the pattern in the each region as a size variation ratio based on a relation between the effective numerical aperture and a size variation of the pattern for the each region to be exposed.
A manufacturing method of a photomask having an exposure pattern to be transferred by lithography, comprising the steps of:
- calculating a numerical aperture to a pattern in a region, for each region to be exposed;
- calculating a correction amount of flare generated at a time of exposure for the pattern in the each region, as a size variation ratio based on a relation between the effective numerical aperture and a size variation of the pattern for the each region to be exposed;
- and
- forming the exposure pattern based on the calculated correction amount.
A manufacturing method of a photomask having an exposure pattern to be transferred by lithography, comprising:
- calculating, in each region to be exposed, a point spread function of the flare by using an experimental mask to estimate a local flare generated when transferring the exposure pattern, on a basis of a measurement result of the experimental mask and in conformity with exposure conditions of the each region;
- calculating, for each region to be exposed, a effective numerical aperture to a pattern in the each region based on a light intensity distribution of the flare;
- and
- calculating a flare correction amount for the pattern in the each region as a size variation ratio based on a relation between the substantial numerical aperture effective numerical aperture and a size variation of the pattern for the each region to be exposed;
- and
- forming the exposure pattern based on the calculated correction amount.
A flare correction apparatus correcting a local flare generated at a time of exposure when manufacturing a semiconductor device comprising:
- a point spread function calculator to calculate, in each region to be exposed, a point spread function of the flare by using an experimental mask to estimate the flare, on a basis of a measurement result of the experimental mask and in conformity with exposure conditions of the each region;
- a effective numerical aperture calculator to calculate, for each region to be exposed, a effective numerical aperture to a pattern in the each region based on a light intensity distribution of the flare;
- and
- a flare correction amount calculator to calculate a flare correction amount for the pattern in the each region as a size variation ratio based on a relation between the effective numerical aperture and a size variation of the pattern for the each region to be exposed.
An exposure method to form a resist pattern on a semiconductor substrate comprising the steps of:
- performing a first exposure to a first region and a second region on the semiconductor substrate;
- and
- performing a second exposure to the second region on the semiconductor substrate,
- wherein, in the second exposure step, a mask pattern is transferred to the second region after a step of correcting a size shift amount by a size variation ratio based on a relation between a effective numerical aperture to a pattern in the second region and a size variation of the pattern for the second region to be exposed.
Dependencies are inferred from the claim text.