JP2006156864A - Resist pattern line width calculating method, mask pattern line width correction method, optical proximity effect correction method, exposure mask fabricating method, electron drawing method for fabricating the exposure mask, exposure method, and semiconductor device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of calculating a resist pattern line width on the basis of which a pattern line width is calculated for optical proximity effect correction. <P>SOLUTION: The method of calculating the resist pattern line width comprises steps of: (A) transferring a mask pattern having a line pitch P<SB>m</SB>, and a mask pattern line width ML<SB>(m, n)</SB>on an exposure mask onto a resist material layer formed on a substrate to obtain a resist pattern line width RL<SB>(m, n)</SB>in a resist pattern; (B) obtaining M pieces of resist pattern line width curves in which the mask pattern line width is an independent variable, and the resist pattern line width is a dependent variable; and then (C) substituting a mask pattern line width ML<SB>(i, j)</SB>into a resist pattern line width function DR<SB>i</SB>in a desired pitch P<SB>i</SB>and mask pattern line width ML<SB>(i, i)</SB>, thereby obtaining a calculated resist pattern line width value CRL(<SB>i, j</SB>). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention has applied a method for calculating a resist pattern / line width in a resist pattern formed through an exposure mask used in a photolithography process in the manufacturing process of a semiconductor device, and a method for calculating the resist pattern / line width, The present invention relates to a mask pattern / line width correction method, an optical proximity effect correction method, an exposure mask manufacturing method, an electron beam drawing method for manufacturing an exposure mask, an exposure method, and a semiconductor device manufacturing method.

  An exposure mask used in a photolithography process in the manufacturing process of a semiconductor device has a structure in which a light-shielding thin layer or a semi-light-shielding thin layer is provided on a substrate such as a glass substrate that is transparent to exposure light. Have. In manufacturing a semiconductor device, a mask pattern formed on an exposure mask is transferred to, for example, a photoresist formed on a semiconductor substrate. Hereinafter, a pattern formed on an exposure mask is referred to as a mask pattern, a plurality of design patterns converted into data is referred to as design pattern data, and electron beam drawing pattern data is referred to as drawing pattern data. The pattern formed in the above may be referred to as a resist pattern. For example, the design pattern data for producing an exposure mask is composed of, for example, a stream format called GDSII / Stream in which the design pattern is expressed in a polygon, or a drawing format expressed only in a rectangle and a trapezoid. ing.

  By the way, when the mask pattern is transferred to, for example, a photoresist formed on a semiconductor substrate by irradiating the exposure mask with exposure light, an optical proximity effect occurs, and the shape of the pattern formed on the photoresist is the design pattern. There arises a problem that it is different from the shape. That is, when a mask pattern having a size on the order of the wavelength of the exposure light is transferred to the photoresist in the photolithography process in the manufacturing process of the semiconductor device, the interference phenomenon of the exposure light becomes remarkable, and the pattern formed in the photoresist The optical proximity effect that causes a difference between the dimension and the dimension of the design pattern is a problem. The optical proximity effect appears as a phenomenon such as a decrease in the line width of an isolated pattern (for example, an isolated line) or a contraction of an end portion of the isolated pattern (for example, an isolated line), and causes deterioration in gate line width controllability and a decrease in alignment margin . As a result, the variation in transistor characteristics increases, and eventually the chip production yield decreases, which has a significant adverse effect on the production efficiency of the semiconductor device. This problem becomes particularly fatal in memory cells that require a high degree of integration with a large number of repetitive patterns. Therefore, an advanced automatic optical proximity effect based on a light intensity simulation corresponding to a memory cell with a finer design rule. An Optical Proximity Effect Correction (OPC) system has been developed.

  In order to correct the optical proximity effect described above, it is necessary to obtain an optimum dose amount for the design pattern or to correct the shape of the design pattern. More specifically, for example, when creating pattern data for electron beam drawing from design pattern data of a semiconductor device, it is necessary to correct the optical proximity effect on the design pattern data.

  For this purpose, the mask pattern / line width and line pitch in the mask pattern provided on the exposure mask under various conditions, and the resist in the resist pattern obtained when the mask pattern is transferred to the resist material layer. It is necessary to obtain in advance a pattern / line width relationship (hereinafter, sometimes referred to as a line width relationship in the mask pattern / resist pattern for convenience).

  By the way, the measured values of the resist pattern and line width observed in the actual measurement system include the exposure mask, the track (coating / developing), the exposure apparatus, the material (resist material / antireflection film), and the dimension measurement. Error elements and error factors are included, resulting in a difference from the true value. Here, examples of error elements and error factors in the exposure mask include errors that occur during mask pattern processing in the exposure mask, deflection of the exposure mask, and the like. Further, as error elements / error factors in the track (coating / development), there can be exemplified resist material coating variation, development variation, and PEB (Post Exposure Bake) plate temperature distribution. Furthermore, examples of error elements and error factors in the exposure apparatus include a focus error, an exposure amount error, and an error of the exposure apparatus itself. In addition, as an error factor / error factor in a material (resist material / antireflection film), there can be mentioned a variation in manufacturing the material. Furthermore, the resist pattern / line width in a resist pattern is usually measured by a dimension measuring instrument such as a CD-SEM (Critical Dimension Scanning Electron Microscope). And errors and variations caused by the operator can be exemplified.

  Therefore, in order to increase the reliability of the data regarding the relationship between the line width in the mask pattern / resist pattern, a large number of mask patterns having the same mask pattern / line width and line pitch are transferred to the resist material layer, It is necessary to measure the resist pattern / line width and use the average of the obtained measurement values as a representative value. However, since the relationship between the line widths of a large number of mask patterns / resist patterns is usually required, such work requires a great deal of labor and man-hours.

JP 2001-244210 A

  In a simulation for modeling and calculating the impurity distribution of a semiconductor element, a model parameter determination method for process simulation that optimizes model parameters that depend on manufacturing conditions such as temperature and time in particular, that is, calculation time is short and accuracy is high. A process simulation model parameter determination method capable of performing model parameter fitting for semiconductor process simulation well is known from Japanese Patent Application Laid-Open No. 2001-244210.

  However, this patent publication discloses a specific method for obtaining the relationship between the line width in the mask pattern / resist pattern, a method for calculating a resist pattern / line width that changes due to the optical proximity effect, and optical proximity effect correction. There is no description regarding the method.

  Accordingly, an object of the present invention is to provide a mask pattern / line width and line pitch in a mask pattern provided in an exposure mask, and a resist pattern / line in a resist pattern obtained when the mask pattern is transferred to a resist material layer. A method for calculating a resist pattern / line width, which is a precondition for calculating a mask pattern / line width for optical proximity effect correction, by obtaining a width relationship (a relationship between a mask pattern / a line width in a resist pattern) with high accuracy; Mask pattern / line width correction method, optical proximity effect correction method, exposure mask manufacturing method, electron beam drawing method for manufacturing exposure mask, and exposure method to which the resist pattern / line width calculation method is applied And a method of manufacturing a semiconductor device.

The method for calculating the resist pattern and line width of the present invention for achieving the above-described object is as follows.
(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} into the resist pattern / line width function DR _i .
It consists of a process.

Here, “the line pitch P _m in the exposure mask (where m = 1, 2, 3,..., M), mask pattern / line width ML, which is the process described in (A) above”. _{(m, n)} (where n = 1, 2, 3,..., N) is transferred to a resist material layer formed on the substrate, and the resist pattern line width in the resist pattern is transferred. The process of “determining RL _{(m, n)} ” is referred to as process (A) for convenience.

Further, in the process described in the above (B), “the mask pattern / line width ML _{(m, n)} and the resist pattern / line width RL _{(m, n)} when the line pitch P _m is fixed” Based on the relationship, the operation of obtaining the _mth resist pattern / line width function DR _m using the mask pattern / line width as an independent variable and the resist pattern / line width as a dependent variable is performed from m = 1 to n = M. The process of obtaining M resist patterns and line width functions by performing M times until is referred to as a process (B) for convenience.

Furthermore, “desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j),} which is the process described in (C) above. (Where j is an integer from 1 to N), and the mask pattern / line width ML _{(i, j)} is substituted into the resist pattern / line width function DR _i , the calculated resist pattern / line width The process of “determining CRL _{(i, j)} ” is referred to as process (C) for convenience.

In the mask pattern / line width correction method of the present invention for achieving the above object, the step (A) is performed, then the step (B) is performed, and then the step (C) is performed.
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
It comprises the process.

In addition, the step of “correcting the mask pattern / line width ML _{(i, j)} based on the resist pattern / line width calculation value CRL _{(i, j)} ”, which is the step described in (D) above. For convenience, it is referred to as step (D).

  An optical proximity effect correction method of the present invention for achieving the above object is an optical proximity effect correction method for design pattern data obtained by converting a plurality of design patterns into data, and after executing step (A), B) is performed, then each step of performing step (C) and then performing step (D) is provided.

In order to achieve the above object, the exposure mask manufacturing method of the present invention performs optical proximity effect correction on design pattern data obtained by converting a plurality of design patterns into data, and uses the obtained design pattern data after correction. Using an etching mask obtained by developing the electron beam resist after performing electron beam drawing on the electron beam resist formed on the mask blanks based on the created electron beam drawing pattern data A method for producing an exposure mask comprising a step of etching blanks,
In the optical proximity effect correction for the design pattern data, after performing the step (A), the step (B) is performed, then the step (C) is performed, and then the step (D) is performed. Is included.

The electron beam drawing method for producing the exposure mask of the present invention to achieve the above object performs optical proximity effect correction on design pattern data obtained by converting a plurality of design patterns into data, and the obtained correction An electron beam drawing method for carrying out electron beam drawing on an electron beam resist formed on a substrate based on electron beam drawing pattern data created from later design pattern data,
In the optical proximity effect correction for the design pattern data, after performing the step (A), the step (B) is performed, then the step (C) is performed, and then the step (D) is performed. Is included.

The exposure method of the present invention for achieving the above object performs an optical proximity effect correction on design pattern data obtained by converting a plurality of design patterns into data, and an electron created from the corrected design pattern data obtained. After performing electron beam drawing on the electron beam resist formed on the mask blanks based on the line drawing pattern data, the mask blanks are etched using the etching mask obtained by developing the electron beam resist. An exposure method using the exposure mask produced in this manner, irradiating the exposure mask with exposure light, and transferring the mask pattern formed on the exposure mask to a photoresist formed on a substrate,
In the optical proximity effect correction for the design pattern data, after performing the step (A), the step (B) is performed, then the step (C) is performed, and then the step (D) is performed. Is included.

In order to achieve the above object, a semiconductor device manufacturing method according to the present invention performs optical proximity effect correction on design pattern data obtained by converting a plurality of design patterns into data, and creates the resulting design pattern data after correction. After performing electron beam drawing on the electron beam resist formed on the mask blanks based on the electron beam drawing pattern data, the mask blanks are developed using the etching mask obtained by developing the electron beam resist. The exposure mask produced by etching is used, the exposure mask is irradiated with exposure light, the mask pattern formed on the exposure mask is transferred to the photoresist formed on the substrate, and the photo A method of manufacturing a semiconductor device including a step of etching a substrate using an etching mask obtained by developing a resist,
In the optical proximity effect correction for the design pattern data, after performing the step (A), the step (B) is performed, then the step (C) is performed, and then the step (D) is performed. Is included.

The resist pattern / line width calculation method of the present invention, the mask pattern / line width correction method of the present invention, the optical proximity correction method of the present invention, the exposure mask preparation method of the present invention, and the exposure mask of the present invention In the electron beam drawing method for manufacturing, the exposure method of the present invention, or the semiconductor device manufacturing method of the present invention (hereinafter collectively referred to simply as the present invention), the step (B in), based on the least square method, it is preferable to obtain the resist pattern line width function DR _m. Alternatively, in the present invention including this preferred embodiment, following the step (C), the mask pattern / line width is fixed, the line pitch is an independent variable, and the calculated resist pattern / line width is a dependent variable. It is preferable to obtain the N optical proximity effect correction curves.

  As a specific method for performing optical proximity correction, for example, model-based optical proximity correction based on the method of Kernel Convolution (see, for example, Nicolas B. Cobb, "Fast Optical and Process Proximity Correction Algorithms for Integrated Circuit Manufacturing") And optical proximity effect correction based on rule base (graphic calculation) and optical proximity effect correction based on a combination of model base and rule base.

  For example, the mask for exposure is formed on a glass substrate such as soda lime glass, low expansion glass, or synthetic quartz glass that is transparent to exposure light, on a light shielding thin layer or semi-light shielding thin layer (these layers) The thin layer may be a single layer or multiple layers). In the present invention, as an exposure mask, a normal exposure mask in which a mask pattern made of a light shielding thin layer is formed, a phase shift mask, and a halftone phase shift mask in which a mask pattern made of a semi-light shielding thin layer is formed Can be illustrated. The exposure mask may be the same as the exposure mask (that is, the master mask) produced by etching the mask blank using the etching mask obtained by developing the electron beam resist. It may be a working mask copied from a master mask.

  As a substrate in the electron beam drawing method, a light-shielding thin layer or a semi-light-shielding thin layer made of metal or metal oxide (such as soda lime glass, low expansion glass, or synthetic quartz glass) transparent to exposure light (these The thin layer may be a single layer or a multi-layer).

Alternatively, as a substrate in an electron beam drawing method, an exposure method, or a semiconductor device manufacturing method, a semiconductor substrate, a semi-insulating substrate, an insulating substrate, or a layer to be processed formed on these substrates is exemplified. Can do. Specifically, the layer to be treated is a polycrystalline silicon layer doped with impurities; a metal layer such as aluminum alloy, tungsten, copper, or silver; a metal compound layer such as tungsten silicide or titanium silicide; A laminated structure of a polycrystalline silicon layer and a metal compound layer such as tungsten silicide or titanium silicide, a laminated structure of a polycrystalline silicon layer doped with impurities, a metal compound layer such as tungsten silicide or titanium silicide, and an insulating film; It can be illustrated. Here, as an insulating film or an insulating _{layer, SiO 2, BPSG, PSG,} BSG, AsSG, SbSG, NSG, SOG, LTO (Low Temperature Oxide, low temperature CVD-SiO _2), SiN, known insulating material such as SiON, Or what laminated | stacked these insulating materials can be mentioned.

A pattern data correction apparatus (including a placement / wiring tool) suitable for carrying out the present invention is a pattern data correction apparatus for performing optical proximity effect correction on design pattern data obtained by converting a plurality of design patterns into data. ,
(A) input means for inputting design pattern data;
(B) correction means, and
(C) output means for outputting design pattern data after correction;
Consisting of
The correction means is
(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i .
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
It is characterized by that.

  This pattern data correction apparatus may be incorporated in an apparatus for creating design pattern data, or in an electron beam drawing apparatus, or may be an apparatus independent of these apparatuses.

  Here, the input means may be any means as long as it is a means capable of designating or inputting a mask pattern / line width, a resist pattern / line width actual measurement value, design pattern data, etc. to the pattern data correction device, For example, a keyboard and a touch panel can be exemplified. Alternatively, when design pattern data recorded on a recording medium such as a flexible disk, CD-ROM, or DVD is input to the pattern data correction device, or the design pattern data recorded on another data processing device is used as the pattern data correction device. In this case, the input means may be a hard disk, a communication line, a LAN, a WAN, or the like that receives and stores these design pattern data. Furthermore, when the design pattern data is input in the form of an electrical signal, the input means can be an input terminal.

  The output means may be an output terminal for outputting design pattern data subjected to optical proximity effect correction. Alternatively, the output means can be a printer or an XY plotter that can record the corrected design pattern on paper, film, etc. based on the corrected design pattern data.

  The correction means executes the resist pattern / line width calculation method of the present invention, the mask pattern / line width correction method of the present invention, or the optical proximity effect correction method of the present invention. The correction means can be composed of storage means such as RAM, ROM, optical storage medium and the like and a CPU. This storage means stores various creation programs, processing programs, resist pattern / line width calculation methods, mask pattern / line width correction methods, optical proximity correction method processing programs, various tables, and rules. Yes. The pattern data correction device further includes design pattern data storage means for storing the input design pattern data and post-correction design pattern data storage means for storing the corrected design pattern data. May be. These design pattern data storage means and the storage means for storing the corrected design pattern data can be constituted by a memory such as a RAM or a hard disk, for example.

  In the present invention, the mask pattern is transferred to the resist material layer, and the resist pattern / line width (actually measured value) in the resist pattern is obtained. Since the various error elements and error factors described in the above are included, there is a difference from the true value. However, since the resist pattern / line width function is obtained with the mask pattern / line width as an independent variable and the resist pattern / line width as a dependent variable, the resist pattern / line width function is determined once the mask pattern / line width and line pitch are determined. Therefore, the calculated resist pattern / line width can be obtained with high accuracy. That is, it is possible to evaluate with high accuracy how much the resist pattern line width formed in the resist material layer changes due to the optical proximity effect on the basis of the mask pattern line width. In other words, when it is necessary to develop the theory based on experimental values, it is necessary to obtain highly accurate measurement values. However, in the present invention, modeling of optical proximity effect correction is performed with high accuracy. Therefore, the optical proximity effect correction can be performed with high accuracy. In addition, the resist pattern / line width function (curve), which is the basic data for obtaining such a calculated resist pattern / line width, is a combination of a plurality of (mask pattern / line width, measured resist pattern / line width measured values). Therefore, it is possible to reduce errors contained in the resist pattern / line width function (curve) itself, exposure mask, track (coating / developing), exposure apparatus, and material (resist material / antireflection). It is possible to obtain a resist pattern / line width function (curve) in which error elements and error factors of processes such as (film) and dimension measurement are relaxed. In addition, within the range of measurement values, it is possible to acquire data (resist pattern / line width calculation value) that is equal to or greater than the number of measurement points.

  Hereinafter, the present invention will be described based on examples with reference to the drawings.

  Example 1 relates to a resist pattern / line width calculation method according to the present invention, a mask pattern / line width correction method according to the present invention, and an optical proximity effect correction method. The resist pattern / line width calculation method, mask pattern / line width correction method, and optical proximity effect correction method of the first embodiment will be specifically described below with reference to FIGS. In the following embodiments, the pattern data correction apparatus (including the placement / wiring tool) described above is used.

  Also, when a mask pattern is formed by exposure light on a resist material layer formed on a semiconductor substrate, one used for reduction projection is called a reticle, and one used for one-to-one projection is called a mask, or In some cases, a reticle corresponding to the master disk is called a reticle, and a duplicate of the reticle is called a mask. This is called an exposure mask. Further, in the following embodiments, a 5 times exposure mask, that is, an exposure mask having a mask pattern design size of 5 formed on the exposure mask is used when the resist pattern design size is 1. . In the following description, the length and size related to the pattern are the length and size converted on the resist pattern (transfer pattern) unless otherwise specified. When obtaining the length and size of the mask pattern formed on the exposure mask, the length and size converted on the resist pattern (transfer pattern) may be multiplied by 5 for example. Further, unless otherwise specified, the unit of length and width is “nm”.

[Step-100]
First, in the exposure mask, the line pitch P _m (where m = 1, 2, 3,..., M), the mask pattern / line width ML _{(m, n)} (where n = 1, 2, 3.., N) was transferred to a resist material layer formed on the substrate, and a resist pattern / line width RL _{(m, n)} in the resist pattern was obtained.

Specifically, the exposure mask was a Levenson type phase shift mask. The line pitch P _m was set as shown in Table 1 below.

[Table 1]
n P _n (nm)
1 220
2 260
3 300
4 400
5 500
6 700
7 950
8 1200

When the minimum width at the line pitch P _m is ML _{(m, 1)} and the maximum width is ML _{(m, N)} , the mask pattern / line width ML _{(m, n)} is
ML _{(m, n)} = ML _{(m, 1)} + 10 × (n−1)
ML _{(m, N)} = ML _{(m, 1)} + 10 × (N−1)
Are in a relationship. Furthermore, the mask pattern line length was set to 800 nm, and eight mask pattern lines were provided at each line pitch P _m as schematically shown in FIG. In FIG. 2, “0 degree” and “180 degree” mean the phase of the exposure light passing through each mask pattern.

Then, using such an exposure mask, the mask pattern provided on the exposure mask is transferred (exposed) to the resist material layer formed on the substrate in an actual process, and the resist material layer is The resist pattern / line width RL _{(m, n)} in the obtained resist pattern was obtained as an actual measurement value. The resist pattern / line width RL _{(m, n)} was measured at the center in the length direction of the mask pattern / line. The actually measured resist pattern / line width RL _{(m, n)} includes the effect of the optical proximity effect, and further includes various error elements and error factors described in the related art. And there is a difference with the true value.

In addition, in order to verify the resist pattern / line width RL _{(m, n)} , the resist pattern / line width was obtained by simulation using Prolith (KLA-Tencor) which is a commercially available lithography simulator. . Note that an aggregation (resist) parameter model (LPM) was used as a simulation model.

  Here, the exposure conditions and the specifications of the resist material layer used were as shown in Table 2 below.

[Table 2]
Light source wavelength: 193nm
Lens numerical aperture (NA): 0.70
Coherence factor (σ): 0.30
Illumination shape: Normal illumination resist material layer film thickness: 250 nm
Resist contrast: 12
Absorption coefficient of resist material: 0.8 μm ⁻¹
Resist material diffusion length: 10 nm

  Here, the resist contrast is an index of how much the resist material is exposed to a certain amount of light, and the diffusion length of the resist material is the amount of proton generated by exposure when the resist material is exposed and developed. The distance traveled is an index indicating the blurring state of the pattern image formed on the resist material layer.

A mask pattern having a mask pattern / line width ML _{(m, n)} in each of P _m (m = 1, 2,..., 8) is transferred to a resist material layer formed on the substrate, and a resist pattern The results obtained by actually measuring the resist pattern / line width RL _{(m, n)} in FIG. 3 are shown in FIGS. 3A and 3B, FIGS. 4A and 4B, and FIG. (B) is shown by black rhombus marks in the graphs of (A) and (B) in FIG.

[Step-110]
Next, based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed, the mask pattern line width is set as an independent variable. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. A line width function (curve) was obtained. Such resist pattern / line width functions are shown in FIGS. 3A and 3B, FIGS. 4A and 4B, FIGS. 5A and 5B, and FIG. In the graph of (B), it shows with the curve of a quadratic function. Here, a resist pattern / line width function DR _m was obtained based on the least square method. FIG. 7 shows a general resist pattern / line width function DR. When the exposure mask is a Levenson type phase shift mask, the resist pattern / line width function DR is a quadratic function when the mask pattern / line width is ML.
DR (ML) = a ₀ + a ₁ · ML + a ₂ · ML ²
It is empirically known that it can be expressed in Here, a ₀ , a ₁ and a ₂ are coefficients.

[Step-120]
Next, the desired line pitch P _i (where i is an integer from 1 to M) and mask pattern line width ML _{(i, j)} (where j is an integer from 1 to N) in, by substituting a mask pattern line width ML _{(i, j)} in the resist pattern line width function DR _i, the resist pattern line width calculated values CRL _{(i, j)} was determined.

Specifically, for example, the mask is applied to the resist pattern / line width function DR ₃ (see FIG. 4A ₎ for the line pitch P ₃ = 300 nm and the mask pattern / line width ML _(3,5) = 110 nm. By substituting the pattern / line width ML _(3,5) , the resist pattern / line width calculated value CRL _(3,5) can be obtained.

[Step-130]
Then, N optical proximity correction curves (one of which is shown in FIG. 8) with the mask pattern / line width fixed, the line pitch as an independent variable, and the resist pattern / line width calculation value as a dependent variable. Asked.

[Step-140]
Next, the mask pattern / line width ML _{(i, j)} was corrected based on the calculated resist pattern / line width CRL _{(i, j)} . Specifically, for example, the mask pattern / line width ML ′ when the resist pattern / line width calculation value CRL ′ becomes a desired value is obtained by back calculation based on the optical proximity correction curve, thereby obtaining the mask pattern / line width. The width can be corrected. That is, if a mask pattern having a mask pattern / line width ML ′ obtained by back calculation is formed on an exposure mask, when the mask pattern is transferred to a resist material layer formed on a substrate, a resist pattern is formed in the resist pattern. The pattern line width (= CRL ′) can be obtained. Thereafter, known optical proximity effect correction is performed on the mask pattern.

[Step-150]
Then, electron beam drawing pattern data is created from the corrected design pattern data. The method of creating the electron beam drawing pattern data depends on what type of electron beam drawing apparatus is used, such as a raster scanning method or a vector scanning method, but can be performed by a known method. That is, for example, the design pattern data in the corrected drawing format is converted into electron beam deflection data (corresponding to electron beam drawing pattern data) by the electron beam drawing apparatus, and the design pattern data is changed by changing the aperture. The same shape of electron beam irradiation is performed.

  In creating the drawing pattern data when the design pattern data is in the stream format, for example, the design pattern data is converted into a bitmap, and then the optical proximity effect of the present invention is based on the bitmapped data. By executing the correction method and correcting the mask pattern, it is possible to obtain design pattern data in which the mask pattern is corrected. The obtained design pattern data is a stream format, and the design pattern data in such a format is converted into, for example, a drawing format by a known method. Then, drawing pattern data is created from the design pattern data of the corrected drawing format.

  The calculated resist pattern / line width when the mask pattern / line width ML = 110 nm is substituted into the N optical proximity effect correction curves thus obtained, and the resist pattern obtained in [Step-100]. The measured value of the line width, and further the resist pattern and line width (simulated value) obtained by simulation are shown in Table 3 below, and further shown in FIG.

  Comparing the calculated values of resist pattern and line width with the measured values of resist pattern and line width, it can be seen that there is a difference of about 3 nm when the line pitch is 300 nm and 400 nm. This is considered to be caused by various error factors and error factors described in the prior art including the above.

Thus, by calculating the optical proximity effect correction curve, if the mask pattern / line width ML _n and the line pitch (indicated by “A” in FIG. 8) are determined, the calculated resist pattern / line width is obtained. It is possible to determine with high accuracy how much the resist pattern line width formed in the resist material layer changes due to the optical proximity effect on the basis of the mask pattern line width. In other words, optical proximity effect correction can be performed with high accuracy. In addition, the resist pattern / line width function, which is basic data for obtaining such an optical proximity effect correction curve, includes a mask pattern / line width ML _{(m, n)} and a resist pattern / line width RL _{(m, n)} . More specifically, since it is obtained by the method of least squares, the error contained in the resist pattern / line width function itself can be reduced, and an exposure mask, track (coating) / Development), exposure apparatus, material (resist material / antireflection film), and dimensional measurement, a resist pattern / line width function in which error elements and error factors are alleviated can be obtained.

  In addition, as described in the prior art, the actual measurement value includes various error factors. However, in the first embodiment, the resist pattern line is based on the approximated and interpolated resist pattern line width function. Since the width calculation value is obtained, the error per actually measured point can be statistically suppressed. As a result, so-called jump data (data that deviates abnormally from the resist pattern / line width function when using the resist pattern / line width function as a reference) is not used as basic data for optical proximity effect correction. The OPC model accuracy in proximity effect correction can be improved. Here, the OPC model is a model used in model-based OPC, and modeling with an experimental value (length measurement value) with less error is indispensable for improving the accuracy of OPC. As shown in FIG. 9, there is a difference of 3 nm when the line pitch is 300 nm and 400 nm, but it is reasonable to consider that the actual measurement value includes an error when compared with the simulation value. . Since the resist pattern / line width calculation value obtained by substituting the mask pattern / line width into the resist pattern / line width function is used as basic data for optical proximity correction, OPC in optical proximity correction Model accuracy can be improved.

  The second embodiment is a modification of the first embodiment. In Example 1, the exposure mask was a Levenson type phase shift mask. On the other hand, in Example 2, the exposure mask was a so-called binary mask and a halftone phase shift mask composed of a light shielding region and a light transmission region.

[Step-200]
In the same manner as in [Step-100] of the first embodiment, first, the line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{( m, n)} (where n = 1, 2, 3,..., N) is transferred to a resist material layer formed on the substrate, and the resist pattern line width RL in the resist pattern is transferred. _{Find (m, n)} . The line pitch P _m is as shown in Table 1. Mask pattern / line width ML _{(m, n)} , mask pattern / line length, number of mask pattern / line at each line pitch, resist pattern / line width measurement point, The specific method for obtaining the resist pattern / line width RL _{(m, n)} was the same as in Example 1.

  Here, the exposure conditions and the specifications of the resist material layer used were as shown in Table 4 below.

[Table 4]
Light source wavelength: 193nm
Lens numerical aperture (NA): 0.75
Coherence factor (σ): 0.85
Illumination shape: 2/3 annular illumination resist material layer thickness: 250 nm
Resist contrast: 12
Absorption coefficient of resist material: 0.8 μm ⁻¹
Resist material diffusion length: 25 nm

[Step-210]
Next, in the same manner as in [Step-110], the relationship between the mask pattern / line width ML _{(m, n)} and the resist pattern / line width RL _{(m, n)} when the line pitch _Pm is fixed. Based on m = 1 to n = M, the operation of obtaining the _mth resist pattern / line width function DR _m using the mask pattern / line width as an independent variable and the resist pattern / line width as a dependent variable And M resist patterns / line width functions are obtained.

As an example, a mask pattern having a mask pattern and line width ML _{(3, n)} (where n = 1, 2, 3,..., N and N = 18) at a line pitch P ₃ = 300 nm. The results of measuring the resist pattern / line width RL _{(3, n)} in the resist pattern after being transferred to the resist material layer formed on the substrate are indicated by black rhombus marks in the graphs of FIGS. Here, FIG. 10 shows a case where the exposure mask is a binary mask, and FIG. 11 shows a case where the exposure mask is a halftone phase shift mask. Note that ML _{(m, 1)} = 80 nm and ML _{(m, N)} = 170 nm.

For example, the relationship between the mask pattern / line width ML _{(3, n)} and the resist pattern / line width RL _{(3, n)} when the line pitch P _m is fixed to m = 3, that is, P ₃ = 300 nm. Based on the results shown in FIG. 10 and FIG. 11, the third resist pattern / line width function DR ₃ is obtained with the mask pattern / line width as an independent variable and the resist pattern / line width as a dependent variable. Here, when the exposure mask is a binary mask or a halftone phase shift mask, the resist pattern / line width function DR is a cubic function when the mask pattern / line width is ML,
DR (ML) = a ₀ + a ₁ · ML + a ₂ · ML ² + a ₃ · ML ³
It is empirically known that it can be expressed in Here, a ₀ , a ₁ , a ₂ , and a ₃ are coefficients.

Such a resist pattern / line width function DR is created at each line pitch P _m . In other words, M resist patterns and line width functions are obtained by performing M times from m = 1 to m = M. Here, a resist pattern / line width function DR _m is obtained based on the method of least squares.

[Step-220]
Next, in the same manner as in [Step-120], a desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is 1 to N _), by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i , the calculated resist pattern / line width CRL _{(i, j) )}

[Step-230]
Then, N optical proximity effect correction curves are obtained with the mask pattern / line width fixed, the line pitch as an independent variable, and the resist pattern / line width calculation value as a dependent variable.

[Step-240]
Next, the mask pattern / line width ML _{(i, j)} is corrected based on the calculated resist pattern / line width CRL _{(i, j)} . Specifically, for example, the mask pattern / line width can be corrected by calculating back the mask pattern / line width ML ′ when the resist pattern / line width calculated value CRL ′ becomes a desired value. it can. That is, if a mask pattern having a mask pattern / line width ML ′ obtained by back calculation is formed on an exposure mask, when the mask pattern is transferred to a resist material layer formed on a substrate, a resist pattern is formed in the resist pattern. The pattern line width (= CRL ′) can be obtained. Thereafter, known optical proximity correction is performed on the mask pattern, and the same process as [Process-150] of the first embodiment is performed.

The third embodiment is also a modification of the first embodiment. Even in Example 3, the exposure mask was a Levenson type phase shift mask, but the line pitch P _m was as shown in Table 5 below.

[Table 5]
n P _n (nm)
1 200
2 220
3 240
4 260
5 300
6 400
7 500
8 700
9 950
10 1200

The mask pattern line length was 480 nm, 600 nm, 680 nm, 800 nm, 1000 nm, and 1400 nm. Further, when the minimum width at the line pitch P _m is ML _{(m, 1)} and the maximum width is ML _{(m, N)} , the mask pattern / line width ML _{(m, n)} is
ML _{(m, n)} = ML _{(m, 1)} + 10 × (n−1)
ML _{(m, N)} = ML _{(m, 1)} + 10 × (N−1)
Are in a relationship. At each line pitch P _m , as shown schematically in FIG. 2, eight mask pattern lines are provided. Based on the same method as in the first embodiment, the mask pattern lines are arranged at the center in the length direction. The resist pattern / line width RL _{(m, n)} was obtained. The exposure conditions and the specifications of the resist material layer used were the same as in Table 2.

Then, [Step-100] of Example 1 to [Step-140] and performs a similar process, when the fixed mask pattern line width ML _n, independent variables the line pitch, the resist pattern line width calculation N optical proximity effect correction curves related to the resist pattern and line width are obtained with the value as a dependent variable. Further, based on the calculated resist pattern and line width CRL _{(i, j)} , the mask pattern and line width ML _{( i, j)} was corrected.

  Further, based on the relationship between the line widths of the mask pattern / resist pattern thus obtained, the resist pattern / line width obtained by the model base based on the method of Kernel Convolution and the same as [Step-100] of Example 1 The difference from the resist pattern / line width actual measurement value obtained by executing the above process was obtained. The result is shown in FIG.

  If the difference between the value calculated by modeling and the actual measurement value is suppressed to ± 8 nm or less for all patterns, the model is considered to be a highly accurate model. Therefore, the difference could be suppressed to ± 6 nm or less.

  Example 4 relates to the electron beam drawing method of the present invention and the method for producing the exposure mask of the present invention.

  That is, with respect to the electron beam drawing method according to the fourth embodiment, for example, optical proximity effect correction is performed on design pattern data obtained by converting a plurality of design patterns for manufacturing a semiconductor device into data, and the obtained design pattern after correction is obtained. Electron beam drawing is performed on the electron beam resist formed on the substrate based on the electron beam drawing pattern data created from the data. The substrate in Example 4 is a mask blank. And regarding an exposure mask and its manufacturing method, after that, mask blanks are etched using the etching mask obtained by developing an electron beam resist. The optical proximity effect correction of the design pattern data to the design pattern data is performed based on the mask pattern correction method of the present invention described in the first or second embodiment.

  In Example 4, specifically, as shown in a schematic partial cross-sectional view in FIG. 13A, the surface of a glass substrate 10 that is transparent to exposure light as a substrate is shielded from metal. Although the mask blank in which the thin layer 11 is formed is used, it is not limited to the mask blank having such a configuration. Then, for example, a positive electron beam resist 12 is applied on the light shielding thin layer 11, and the electron beam resist 12 is applied to the electron beam resist 12 based on the electron beam drawing pattern data created by the same method as in the first embodiment. To draw an electron beam. This state is shown in FIG. 13B. The hatched portion of the electron beam resist 12 is a portion drawn by an electron beam.

  Next, after developing the electron beam resist 12 (see FIG. 13C), the mask blanks, more specifically, the light shielding thin layer 11 are etched using the patterned electron beam resist 12 as an etching mask. Thus, an exposure mask (master mask) having the structure shown in FIG. 13D can be manufactured.

  Example 5 also relates to an electron beam drawing method of the present invention, and more particularly to an electron beam drawing method for directly drawing an electron beam on an electron beam resist formed on a substrate such as a semiconductor substrate. In Example 5, as shown in the schematic partial cross-sectional view of FIG. 14A, the base is composed of a metal layer 22 made of an aluminum-based alloy formed above the semiconductor substrate 20. However, it is not limited to such a structure. Reference numeral 21 denotes an interlayer insulating layer formed on the semiconductor substrate 20. As for the electron beam drawing method according to the fifth embodiment, for example, an electron created from the corrected design pattern data obtained by correcting design pattern data obtained by converting a plurality of design patterns for manufacturing a semiconductor device into data. Electron beam drawing is performed on the electron beam resist 23 formed on the metal layer 22 as the base based on the pattern data for line drawing. This state is shown in FIG. 14B, and the hatched portion of the electron beam resist 23 is a portion drawn by an electron beam. The design pattern data is corrected based on the optical proximity correction method of the present invention described in the first embodiment.

  Next, after developing the electron beam resist 23 (see FIG. 14C), the substrate, more specifically, the metal layer 22 is etched using the patterned electron beam resist 23 as an etching mask. Thus, the structure shown in FIG. 14D can be manufactured.

  Example 6 relates to an exposure method of the present invention and a method for manufacturing a semiconductor device of the present invention. That is, for the exposure method, for example, optical proximity effect correction is performed on design pattern data obtained by converting a plurality of design patterns into data, and based on the obtained electron beam drawing pattern data created from the corrected design pattern data. Electron beam drawing is performed on the electron beam resist formed on the mask blank. Then, the exposure mask produced by etching a mask blank using the etching mask obtained by developing this electron beam resist is used. Then, the exposure mask is irradiated with exposure light, and the mask pattern formed on the exposure mask is transferred to the photoresist formed on the substrate. Regarding a semiconductor device manufacturing method, a mask pattern formed on an exposure mask is transferred to a photoresist formed on a substrate, and then the substrate is etched using an etching mask obtained by developing the photoresist. To do. The optical proximity effect correction of the design pattern data is performed based on the optical proximity effect correction method of the present invention described in the first embodiment.

  In Example 6, specifically, as shown in a schematic partial cross-sectional view in FIG. 15A, the base body is a metal layer 32 made of an aluminum-based alloy formed above the semiconductor substrate 30. However, the present invention is not limited to this. Reference numeral 31 denotes an interlayer insulating layer formed on the semiconductor substrate 30. Then, for example, a positive photoresist 33 is applied on the metal layer 32. In addition, based on the electron beam drawing pattern data created by the same method as in Example 1, after performing electron beam drawing on the electron beam resist formed on the mask blank, the electron beam resist is developed. An exposure mask 34 produced by etching a mask blank using the etching mask obtained in this way is used. Then, the exposure mask 34 is irradiated with exposure light, and the mask pattern formed on the exposure mask 34 is transferred to the photoresist 33 formed on the metal layer 32 which is a substrate. This state is shown in FIG. 15B, and the hatched portion of the photoresist 33 is the pattern transfer portion.

  Next, after developing the photoresist 33, the substrate, more specifically, the metal layer 32 is etched using the patterned photoresist 33 as an etching mask. Thus, a semiconductor device having the structure shown in FIG. 15C can be manufactured.

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples. The materials and various conditions used in the examples are examples and can be changed as appropriate. Each process in the optical proximity correction method described in the first and second embodiments can also be changed. In some cases, pattern data for electron beam drawing may be generated immediately from the corrected design pattern data while correcting the design pattern data, and electron beam drawing may be performed based on the pattern data for electron beam drawing.

FIG. 1 is a flowchart for explaining a method of calculating a resist pattern / line width according to the first embodiment. FIG. 2 is a diagram schematically showing the mask pattern lines used in the first embodiment. 3A and 3B show the mask pattern / line width and the resist pattern / line width actually measured values when the line pitch is fixed to 220 nm and 260 nm, respectively, and the mask pattern It is a graph which shows the result of having calculated | required the resist pattern line width function which made the mask pattern line width into an independent variable and made the resist pattern line width into a dependent variable based on the relationship between a line width and a resist pattern line width measured value. . 4A and 4B show the mask pattern / line width and the resist pattern / line width actually measured values when the line pitch is fixed to 300 nm and 400 nm in Example 1, and the mask pattern It is a graph which shows the result of having calculated | required the resist pattern line width function which made the mask pattern line width into an independent variable and made the resist pattern line width into a dependent variable based on the relationship between a line width and a resist pattern line width measured value. . (A) and (B) of FIG. 5 respectively show the mask pattern / line width and the resist pattern / line width measured value and the mask pattern / line width when the line pitch is fixed to 500 nm and 700 nm in Example 1. It is a graph which shows the result of having calculated | required the resist pattern line width function which made the mask pattern line width into an independent variable and made the resist pattern line width into a dependent variable based on the relationship between a line width and a resist pattern line width measured value. . 6 (A) and 6 (B) show the mask pattern / line width and the resist pattern / line width actually measured values when the line pitch is fixed at 950 nm and 1200 nm, respectively, and the mask pattern. It is a graph which shows the result of having calculated | required the resist pattern line width function which made the mask pattern line width into an independent variable and made the resist pattern line width into a dependent variable based on the relationship between a line width and a resist pattern line width measured value. . FIG. 7 is a graph showing a general resist pattern / line width function DR _m . FIG. 8 is a graph schematically showing an optical proximity effect correction curve. FIG. 9 shows the calculated resist pattern and line width when the mask pattern and line width ML = 110 nm are substituted into the optical proximity effect correction curve obtained in Example 1, and the measured value of the resist pattern and line width. Furthermore, it is a graph which shows the resist pattern line width (simulation value) calculated | required by simulation. FIG. 10 shows the mask pattern / line width based on the relationship between the mask pattern / line width and the measured resist pattern / line width when the exposure mask is a binary mask and the line pitch is fixed to 300 nm in the second embodiment. 5 is a graph showing the result of obtaining a resist pattern / line width function with the independent variable as a dependent variable and the resist pattern / line width as a dependent variable. FIG. 11 shows a mask based on the relationship between the mask pattern / line width and the measured resist pattern / line width when the exposure mask is a halftone phase shift mask and the line pitch is fixed to 300 nm in the second embodiment. It is a graph which shows the result of having calculated | required the resist pattern line width function which made the pattern line width the independent variable and made the resist pattern line width the dependent variable. FIG. 12 is a graph showing a result of calculating the difference between the resist pattern / line width obtained by using the lithography simulator and the resist pattern / line width obtained by performing the model-based optical proximity effect correction, and the measured resist pattern / line width. It is. 13A to 13D are schematic partial cross-sectional views of mask blanks and the like for explaining the fourth embodiment. 14A to 14D are schematic partial cross-sectional views of a semiconductor substrate and the like for explaining the fifth embodiment. 15A to 15C are schematic partial cross-sectional views of a semiconductor substrate and the like for explaining the sixth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Glass substrate, 11 ... Thin layer for light shielding, 12 ... Electron beam resist, 20, 30 ... Semiconductor substrate, 21, 31 ... Interlayer insulation layer, 22, 32 ... Metal Layer, 23 ... Electron beam resist, 33 ... Photoresist

Claims (11)

(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} into the resist pattern / line width function DR _i .
A method of calculating a resist pattern / line width, comprising a step. In the step (B), based on the method of least squares, a method of calculating the resist pattern line width according to claim 1, characterized in that obtaining the resist pattern line width function DR _m.   Subsequent to the step (C), the mask pattern / line width is fixed, N optical proximity effect correction curves are obtained using the line pitch as an independent variable and the resist pattern / line width calculation value as a dependent variable. The method of calculating a resist pattern / line width according to claim 1. (A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i .
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
A mask pattern / line width correction method comprising the steps of: Wherein in the step (B), based on the least square method, a method of correcting the mask pattern linewidth of claim 4, wherein the obtaining the resist pattern line width function DR _m.   Subsequent to the step (C), the mask pattern / line width is fixed, N optical proximity effect correction curves are obtained using the line pitch as an independent variable and the resist pattern / line width calculation value as a dependent variable. The mask pattern / line width correction method according to claim 4. An optical proximity effect correction method for design pattern data obtained by converting a plurality of design patterns into data,
(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i .
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
A method for correcting an optical proximity effect, comprising a step. An electron formed on the mask blanks based on the electron beam drawing pattern data created from the corrected design pattern data obtained by performing optical proximity effect correction on the design pattern data obtained by converting a plurality of design patterns into data. An exposure mask manufacturing method comprising a step of etching a mask blank using an etching mask obtained by developing an electron beam resist on a line resist and then developing the electron beam resist,
For optical proximity effect correction for the design pattern data,
(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i .
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
A method for manufacturing an exposure mask, comprising a step. An electron beam formed on the substrate based on the electron beam drawing pattern data created from the corrected design pattern data obtained by performing optical proximity effect correction on the design pattern data obtained by converting a plurality of design patterns into data. An electron beam drawing method for performing electron beam drawing on a resist,
For optical proximity effect correction for the design pattern data,
(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i .
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
The electron beam drawing method for producing the exposure mask characterized by including a process. An electron formed on the mask blanks based on the electron beam drawing pattern data created from the corrected design pattern data obtained by performing optical proximity effect correction on the design pattern data obtained by converting a plurality of design patterns into data. Using an exposure mask produced by etching a mask blank using an etching mask obtained by developing an electron beam resist on a line resist and then developing the electron beam resist. An exposure method for irradiating a mask with exposure light and transferring a mask pattern formed on an exposure mask to a photoresist formed on a substrate,
For optical proximity effect correction for the design pattern data,
(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i .
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
An exposure method comprising a step. An electron formed on the mask blanks based on the electron beam drawing pattern data created from the corrected design pattern data obtained by performing optical proximity effect correction on the design pattern data obtained by converting a plurality of design patterns into data. Using an exposure mask produced by etching a mask blank using an etching mask obtained by developing an electron beam resist on a line resist and then developing the electron beam resist. The mask is irradiated with exposure light, the mask pattern formed on the exposure mask is transferred to the photoresist formed on the substrate, and the substrate is etched using the etching mask obtained by developing the photoresist. A method of manufacturing a semiconductor device including a process,
For optical proximity effect correction for the design pattern data,
(A) Line pitch P _m (where m = 1, 2, 3,..., M), mask pattern / line width ML _{(m, n)} (where n = 1, 2) in the exposure mask. , 3..., N) are transferred to a resist material layer formed on the substrate to obtain a resist pattern / line width RL _{(m, n)} in the resist pattern,
(B) The mask pattern line width is an independent variable based on the relationship between the mask pattern line width ML _{(m, n)} and the resist pattern line width RL _{(m, n)} when the line pitch P _m is fixed. The operation of obtaining the _mth resist pattern / line width function DR _m with the resist pattern / line width as a dependent variable is performed M times from m = 1 to n = M, and M resist patterns / line widths are obtained. After getting the line width function,
(C) Desired line pitch P _i (where i is an integer from 1 to M) and mask pattern / line width ML _{(i, j)} (where j is an integer from 1 to N ₎ ), A resist pattern / line width calculation value CRL _{(i, j)} is obtained by substituting the mask pattern / line width ML _{(i, j)} for the resist pattern / line width function DR _i .
(D) Based on the calculated resist pattern / line width CRL _{(i, j)} , the mask pattern / line width ML _{(i, j)} is corrected.
A method for manufacturing a semiconductor device, comprising a step.

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