JP2013004888A - Charged particle beam drawing method, evaluation method of charged particle beam drawing apparatus, and charged particle beam drawing apparatus - Google Patents

Abstract

[Object] To provide a charged particle beam writing method for evaluating a drift amount at a deflection position of a charged particle beam in a short time.
[Configuration] A reference position information acquisition step of irradiating a plurality of reference marks fixed on the stage with a charged particle beam to acquire reference position information of each reference mark, and a charged particle beam to a sample placed on the stage Irradiating and drawing a pattern on the sample, and by deflecting the charged particle beam while the stage is stationary, the reference mark is sequentially irradiated with the charged particle beam, and evaluation position information of each reference mark is obtained. An evaluation position information acquisition step to be acquired, a comparison step for comparing the evaluation position information and the reference position information, and a drift amount calculation step for calculating the drift amount of the beam position in the deflection state of the charged particle beam from the result of the comparison step; And a second drawing step of irradiating the sample with a charged particle beam and drawing a pattern on the sample.
[Selection] Figure 1

Description

  The present invention relates to a charged particle beam drawing method for drawing a figure on a sample, a method for evaluating a charged particle beam drawing apparatus, and a charged particle beam drawing apparatus.

  Lithography technology is used to form a desired circuit pattern on a semiconductor device. In lithography technology, a pattern is transferred using an original pattern called a mask (reticle). In order to manufacture a highly accurate reticle, an electron beam (electron beam) drawing technique having excellent resolution is used.

  There is a variable shaping method as one method of an electron beam writing apparatus that performs electron beam writing on a mask. In the variable shaping method, for example, an electron beam which is shaped by passing through the opening of the first shaping aperture and the opening of the second shaping aperture and is controlled by the deflector is placed on the sample placed on the movable stage. A figure is drawn. A region where electrons are irradiated by one irradiation of an electron beam is called a shot.

  There may be a drift (or beam drift) in which the irradiation position of the electron beam deviates from a desired position during drawing on the mask or waiting for drawing. For example, when the mask is irradiated with an electron beam, reflected electrons are generated. The generated reflected electrons collide with an optical system or a detector in the electron beam drawing apparatus and charge up occurs, and a new electric field is generated. Then, the trajectory of the electron beam deflected and irradiated toward the mask changes. Such charge-up is one cause of electron beam drift.

  Patent Document 1 describes an electron beam drawing apparatus that detects a drift amount of an electron beam using a reference mark.

JP 2010-258339 A

  In the evaluation of the drift amount of the electron beam in the electron beam lithography apparatus, it is desired that the drift amount at the deflection position is evaluated in a state where the electron beam is deflected by the deflector. It is desirable that the evaluation of the drift amount of the electron beam during drawing on the sample be made as fast as possible from the viewpoint of improving the throughput of sample drawing. In addition, it is desirable that the drift amount evaluation not only during drawing but also during the start-up of the electron beam drawing apparatus or during periodic inspections, be similarly accelerated.

  The present invention has been made in consideration of the above-described circumstances, and an object of the present invention is to provide a charged particle beam drawing method and a charged particle beam drawing apparatus for evaluating a drift amount at a deflection position of a charged particle beam in a short time. And a charged particle beam drawing apparatus.

  The charged particle beam drawing method according to one aspect of the present invention includes a reference position information acquisition step of irradiating a plurality of reference marks fixed on a stage with a charged particle beam and acquiring reference position information of each of the reference marks, A first drawing step of irradiating a sample placed on a stage with a charged particle beam and drawing a pattern on the sample, and deflecting the charged particle beam with the stage stationary, thereby sequentially applying the reference mark to the reference mark An evaluation position information acquisition step of irradiating a charged particle beam to acquire evaluation position information of each of the reference marks, a comparison step of comparing the evaluation position information and the reference position information, and the charging from the result of the comparison step A drift amount calculating step for calculating a drift amount of the beam position in the deflection state of the particle beam; and irradiating the sample with a charged particle beam and patterning the sample A second rendering step of rendering, and having a.

  In the charged particle beam writing method according to the above aspect, a deflection sensitivity correction coefficient changing step of changing a deflection sensitivity correction coefficient based on the drift amount is provided after the drift amount calculating step and before the second drawing step. Is desirable.

  In the evaluation method of the charged particle beam drawing apparatus according to one aspect of the present invention, a reference position information acquisition step of irradiating a plurality of reference marks fixed on a stage with a charged particle beam and acquiring reference position information of each of the reference marks An evaluation position information acquisition step of sequentially irradiating the reference mark with the charged particle beam by deflecting the charged particle beam while the stage is stationary, and acquiring evaluation position information of each of the reference marks; and the evaluation A comparison step of comparing position information with the reference position information, and a drift amount calculation step of calculating a drift amount of the beam position in the deflection state of the charged particle beam from the result of the comparison step. To do.

  In the evaluation method of the charged particle beam drawing apparatus according to the aspect described above, it is preferable that the evaluation position information acquisition process is continuously repeated a plurality of times without interposing the movement of the stage.

  A charged particle beam drawing apparatus according to an aspect of the present invention includes a reference position information storage unit that stores reference position information of each of the reference marks obtained by irradiating a plurality of reference marks fixed on a stage with a charged particle beam. And an evaluation position information storage unit for storing evaluation position information of each of the reference marks obtained by sequentially irradiating the reference marks with the charged particle beam by deflecting the charged particle beam while the stage is stationary A comparison unit that compares the evaluation position information and the reference position information, and a drift amount calculation unit that calculates a drift amount of the beam position in the deflection state of the charged particle beam from a comparison result in the comparison unit, It is characterized by having.

  According to the present invention, it is possible to provide a charged particle beam drawing method, a charged particle beam drawing apparatus evaluation method, and a charged particle beam drawing apparatus that evaluate a drift amount at a deflection position of a charged particle beam in a short time. Become.

It is a schematic block diagram of the electron beam drawing apparatus of 1st Embodiment. It is explanatory drawing of the drawing method of the vector scanning system and stage continuous movement system which are employ | adopted by 1st Embodiment. It is process drawing of the electron beam drawing method of 1st Embodiment. It is a figure which shows the specific example of the reference | standard mark used in 1st Embodiment. It is explanatory drawing of an effect | action of the electron beam drawing apparatus and electron beam drawing method of 1st Embodiment. It is process drawing of the electron beam drawing method of 2nd Embodiment. It is process drawing of the evaluation method of the electron beam drawing apparatus of 3rd Embodiment. It is process drawing of the evaluation method of the electron beam drawing apparatus of 4th Embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. Hereinafter, in the embodiment, a configuration using an electron beam will be described as an example of a charged particle beam. However, the charged particle beam is not limited to the electron beam, and may be a beam using charged particles such as an ion beam.

(First embodiment)
The electron beam drawing apparatus according to the present embodiment includes a reference position information storage unit that stores reference position information of each reference mark obtained by irradiating a plurality of reference marks fixed on the stage with an electron beam, and a stage. An evaluation position information storage unit for storing evaluation position information of each reference mark obtained by sequentially irradiating the reference mark with the electron beam by deflecting the electron beam in a stationary state, evaluation position information and reference position information And a drift amount calculation unit for calculating the drift amount of the beam position in the deflection state of the electron beam from the comparison result in the comparison unit.

  In addition, the electron beam drawing method of the present embodiment includes a reference position information acquisition step of irradiating a plurality of reference marks fixed on the stage with an electron beam and acquiring reference position information of each of the reference marks, and the stage. The reference mark is sequentially irradiated with the electron beam by deflecting the electron beam while the stage is stationary with the first drawing step of irradiating the placed sample with the electron beam and drawing the pattern on the sample. An evaluation position information acquisition process for acquiring each evaluation position information, a comparison process for comparing the evaluation position information and the reference position information, and a beam position drift amount in the deflection state of the electron beam is calculated from the result of the comparison process. A drift amount calculating step, and a second drawing step of drawing a pattern on the sample by irradiating the sample with an electron beam.

  In the electron beam drawing apparatus and the electron beam drawing method according to the present embodiment, fluctuations in position information of a plurality of reference marks are evaluated by deflecting the electron beam while the stage is stationary. Therefore, it is possible to evaluate the fluctuation amount of the electron beam position at the deflection position, that is, the drift amount in a short time without providing time for stage movement or the like.

  There are two types of drift in electron beam drift. That is, a shift drift that does not depend on the deflection position of the beam and a deflection drift that depends on the deflection position. According to the present embodiment, it is possible to evaluate the latter deflection drift in addition to the former shift drift.

  FIG. 1 is a schematic configuration diagram of an electron beam drawing apparatus according to the present embodiment. The electron beam drawing apparatus 100 is an example of a charged particle beam drawing apparatus. The electron beam drawing apparatus 100 includes a drawing unit 102 and a control unit 104 that controls the drawing operation of the drawing unit 102. The electron beam drawing apparatus 100 draws a predetermined pattern on the sample 110.

  The drawing unit 102 has a function of drawing by sequentially irradiating the sample 110 with an electron beam using shot data.

  A stage 112 on which the sample 110 is placed is accommodated in the sample chamber 108 of the drawing unit 102. The stage 112 is driven by the control unit 104 in the X direction (left and right direction in the drawing), Y direction (front and back direction in the drawing), and Z direction (up and down direction in the drawing). As the sample 110, for example, there is an exposure mask for transferring a pattern to a wafer on which a semiconductor device is formed. The mask includes, for example, mask blanks on which no pattern is formed. A reference mark for evaluating the drift of the electron beam is fixed to the stage 112 at a distance from the region where the sample 110 is placed.

  In the mask blank, for example, chromium serving as a light shielding film is coated on quartz glass. When placed on the stage 112 of the electron beam drawing apparatus, for example, a resist is applied.

  An electron beam optical system 114 is installed above the sample chamber 108. The electron beam optical system 114 includes an electron gun 116, various lenses 118, 120, 122, 124, 126, a blanking deflector 128, a beam size variable deflector 130, a beam scanning sub deflector 132, and a beam scanning. The main deflector 134, and a first aperture 136 and a second aperture 138 for beam shaping for drawing with a variable shaped beam.

  In addition, a detector 160 is provided that detects reflected electrons generated by irradiating an electron beam to a reference mark fixed on the stage as a current value.

  The control unit 104 includes a drawing data storage unit 106, a shot data generation unit 140, a control circuit 150, a detection unit 161, a reference position information storage unit 162, an evaluation position information storage unit 163, a comparison unit 164, a drift amount calculation unit 165, and A deflection sensitivity correction coefficient calculation unit 166 is provided.

  The drawing data storage unit 106 has a function of inputting drawing data in which a drawing pattern to be drawn on the sample is defined and storing the drawing data. The drawing data is, for example, a circuit pattern of a semiconductor integrated circuit. The drawing data storage unit 106 may be a storage medium, and for example, a magnetic disk or the like can be used.

  The shot data generation unit 140 has a function of converting the drawing data read from the drawing data storage unit 106 into shot data configured in units of electron beam shots.

  The control circuit 150 has a function of controlling the drawing unit 102 based on the shot data generated by the shot data generation unit 140.

  The detection unit 161 has a function of amplifying the electric signal detected by the detector 160 and A / D (analog / digital) conversion.

  The reference position information storage unit 162 has a function of storing reference position information of each reference mark obtained by irradiating a plurality of reference marks fixed on the stage 112 with an electron beam. That is, a signal obtained by measuring a plurality of reference marks by the detection unit 161 is stored as reference position information of the plurality of reference marks. Specifically, the coordinate positions of a plurality of reference marks are stored as initial values.

  The evaluation position information storage unit 163 stores evaluation position information of each reference mark obtained by sequentially irradiating the reference mark with the electron beam by deflecting the electron beam while the stage 112 is stationary. That is, a signal obtained by measuring a plurality of reference marks by the detection unit 161 after acquiring the reference position information is stored as evaluation position information of the plurality of reference marks. Specifically, the coordinate positions of a plurality of reference marks evaluated after acquiring the reference position information are stored.

  The reference position information storage unit 162 and the evaluation position information storage unit 163 may be any storage medium, and for example, a magnetic disk or the like can be used.

  The comparison unit 164 has a function of reading the evaluation position information and the reference position information stored in the evaluation position information storage unit 163 and the reference position information storage unit 162 and comparing them.

  The drift amount calculation unit 165 has a function of calculating the drift amount of the beam position in the deflection state of the electron beam from the comparison result in the comparison unit. Specifically, the fluctuation amount of the coordinate position of each reference mark corresponding to the drift amount of the beam position is calculated.

  The deflection sensitivity correction coefficient calculation unit 166 has a function of calculating a deflection sensitivity correction coefficient from the beam position drift amount calculated by the drift amount calculation unit 165. Here, the deflection sensitivity correction coefficient refers to various factors in the electron beam lithography apparatus such as a deflector and a DAC amplifier (digital / analog converter amplifier) in order to realize a desired irradiation position of the electron beam on the sample. It means a coefficient of an arithmetic expression when performing a calculation on a desired irradiation position in consideration of characteristics, trajectory change of the electron beam due to the charge-up described above, and the like.

For example, specifically, the coefficients of a _{0 to} a ₁₄ and b _{0 to} b ₁₄ of the fourth-order approximation polynomial shown in the following (formula 1) are deflection sensitivity correction coefficients.
X = a ₀ + a ₁ x + a ₂ y + a ₃ x ² + a ₄ xy + a ₅ y ² + a ₆ x ³ + a ₇ x ² y + a ₈ xy ² + a ₉ y ³ + a ₁₀ x ⁴ + a ₁₁ x ³ y + a ₁₂ x ² y ² + a ₁₃ xy ³
+ a ₁₄ y ⁴
Y = b ₀ + b ₁ x + b ₂ y + b ₃ x ² + b ₄ xy + b ₅ y ² + b ₆ x ³ + b ₇ x ² y + b ₈ xy ² + b ₉ y ³ + b ₁₀ x ⁴ + b ₁₁ x ³ y + b ₁₂ x ² y ² + b ₁₃ xy ³
+ b ₁₄ y ⁴
... (Formula 1)
In the above equation, X and Y are actual irradiation position coordinates of the electron beam, and x and y are desired irradiation position coordinates, that is, input position coordinates input to the apparatus.

  The DAC amplifier is a component of the control circuit 150 although not shown in FIG. The input position coordinates input to the apparatus are given as digital signals to the DAC amplifier, converted into analog signals by the DAC amplifier, amplified and output. Then, by the output, the beam scanning sub-deflector 132 and the beam scanning main deflector 134 are controlled, so that the electron beam is irradiated to a desired position of the sample or the reference mark. At this time, the actual irradiation position of the electron beam is controlled to be a desired irradiation position using the relationship expressed by (Expression 1).

Of the deflection sensitivity correction coefficients, a ₀ and b ₀ are coefficients related to shift drift, and a _{1 to} a ₁₄ and b _{1 to} b ₁₄ are coefficients related to deflection drift.

  Drawing data storage unit 106, shot data generation unit 140, control circuit 150, detection unit 161, reference position information storage unit 162, evaluation position information storage unit 163, comparison unit 164, drift amount calculation unit 165, and deflection sensitivity correction coefficient Processing of each function of the calculation unit 166 is performed using, for example, an arithmetic processing device such as a CPU or hardware such as an electric circuit. Alternatively, a combination of software and hardware may be used.

  In FIG. 1, description of the embodiment is omitted except for necessary components. Needless to say, the electron beam lithography apparatus 100 may normally include other necessary configurations.

  Next, an electron beam drawing method according to the present embodiment using the electron beam drawing apparatus 100 will be described with reference to FIGS.

  First, a basic drawing operation of the drawing unit 102 will be described with reference to FIGS. 1 and 2. FIG. 2 is an explanatory diagram of a drawing method using the vector scanning method (two-dimensional scanning method) and the stage continuous movement method employed in the present embodiment. The drawing unit 102 draws on the sample 110 using the shot data generated by the control unit 104.

  In actual drawing, the electron beam emitted from the electron gun 116 is variably controlled by the beam size variable deflector 130, the first aperture 136 and the second aperture 138 for beam shaping, and vector scanning is performed. Drawing processing is performed by the method and the stage continuous movement method.

  First, the pattern 202 to be drawn on the sample 110 is divided into regions called strip-like drawing data stripes 204, and the drawing data stripes 204 are further divided into regions called subfields 206, and only the necessary portions are inside. The variable shaped beam 208 shaped by the first aperture 136 and the second aperture 138 of FIG. 1 is deflected to draw the figure 207 arranged in the subfield 206.

  Drawing processing is performed while the stage 112 (FIG. 1) is continuously moved. At this time, the two-stage deflector of the sub deflector 132 and the main deflector 134 (FIG. 1) is used, and the positioning of the subfield 206 is performed according to the main deflection position data sent from the controller 104 (FIG. 1). The sub-field 206 is drawn by the sub-deflector 132 in accordance with sub-deflection position data, shot size data, and the like sent from the control unit 104.

  When the drawing of one subfield 206 is completed, the drawing of the next subfield 206 is started. When drawing of the drawing data stripe 204, which is a set of a plurality of subfields 206, is finished, the stage 112 (FIG. 1) that has been continuously moved in the X direction is moved stepwise in the Y direction. The above processing is repeated to sequentially draw each drawing data stripe region. Here, the drawing data stripe 204 is, for example, a strip-like drawing region determined by the deflection width of the main deflector 134 (FIG. 1), and the subfield 206 is, for example, the deflection width of the sub deflector 132 (FIG. 1). Is a unit drawing area determined by.

  FIG. 3 is a process diagram of the electron beam writing method of the present embodiment.

  First, in a reference position acquisition step (S110), a plurality of reference marks fixed on the stage are irradiated with an electron beam to acquire reference position information of each reference mark.

  FIG. 4 is a diagram showing a specific example of the reference mark used in the present embodiment. For example, as shown in FIG. 4A, the reference mark portion 500 is provided with 25 cross-shaped reference marks 502. For example, the intersection of the reference marks 502 is the position of each reference mark 502. The reference mark portion is provided on the stage 112 so as to be separated from an area where the sample 110 on the stage is placed.

  For example, the reference mark 502 is formed of a material having a reflectance different from that of the electron beam from the substrate of the reference mark portion 500. For example, the substrate is silicon, and the reference mark 502 is formed of tungsten having a higher reflectance than silicon. It is also possible to use a heavy metal other than tungsten as the reference mark 502.

  As shown in FIG. 4A, the plurality of reference marks 502 do not necessarily have to be individually separated patterns. If the plurality of reference marks 502 can function as a plurality of marks, for example, FIG. As shown in FIG. In the case of FIG. 5B, each of the lattice intersections functions as a different reference mark 502. Further, the reference mark 502 may have a shape other than a cross or a lattice such as a rectangle.

  If the reference mark is fixed on the stage, that is, moves integrally with the stage, it may be detachably mounted.

  The reference position acquisition step (S110) is a step for grasping the initial coordinate positions of the plurality of reference marks 502 in order to evaluate the drift amount of the electron beam later. For example, by stationary the stage, the stationary reference mark 502 is deflected with an electron beam to sequentially irradiate it, and the detector 160 monitors the reflected electron waveform to determine the coordinate position. It is possible to evaluate. The obtained result is stored in the reference position information storage unit 162.

  Next, in the first drawing step (S120), a pattern is drawn on the sample by irradiating the sample, for example, a mask, placed on the stage with the above-described drawing method.

  Next, in the evaluation position information acquisition step (130), after moving the stage to a position where the reference mark unit 500 can be irradiated with the electron beam, the reference mark 520 is deflected while the stage is stationary. Are sequentially irradiated with an electron beam to obtain 25 pieces of evaluation position information for each of the reference marks 502 in FIGS. 4A and 4B. The coordinates after the first drawing step (S120) are obtained by sequentially irradiating each stationary reference mark 502 by deflecting the electron beam and monitoring the waveform of the reflected electrons by the detector 160. It is possible to evaluate the position. The obtained result is stored in the evaluation position information storage unit 163.

  Next, in the comparison step (S140), the comparison unit 164 first reads the reference position information and the evaluation position information stored in the reference position information storage unit 162 and the evaluation position information storage unit 163. Then, the evaluation position information is compared with the reference position information. Specifically, the coordinate positions of the reference marks 502 are compared.

  Next, in the drift amount calculation step (S150), the drift amount calculation unit 165 calculates the drift amount of the beam position in the deflection state of the electron beam from the result of the comparison step. That is, the drift amount at the deflection position of the electron beam is evaluated.

  Next, in the deflection sensitivity correction coefficient calculation step (S160), the deflection sensitivity correction coefficient calculation unit 166 calculates the deflection sensitivity correction coefficient of the electron beam based on the drift amount. Specifically, for example, the coefficient of the above (formula 1) is calculated.

  Next, in the second drawing step (S170), the sample placed on the stage, for example, a mask, is irradiated with an electron beam by the above-described drawing method, and a pattern is drawn on the sample. Note that the separation between the first drawing step (S120) and the second drawing step (S170) is an appropriate time position during the drawing of one mask.

  In the present embodiment, the drawing method up to the second drawing step (S170) has been described. For example, after the second drawing step (S170), the evaluation position information acquisition step (S130) to deflection are further performed. It is also possible to evaluate the drift amount of the electron beam generated during the second drawing step (S170) by repeating the sensitivity correction coefficient calculation step (S160). These processes may be repeated further.

  FIG. 5 is an explanatory diagram of the operation of the electron beam drawing apparatus and the electron beam drawing method of the present embodiment. FIG. 5A shows the case of this embodiment, and FIG. 5B shows the case of the prior art. As shown in FIG. 5A, in this embodiment, the electron beam is deflected by, for example, the main deflector 134 while the stage is stationary, and a plurality of reference marks 502 are continuously evaluated. On the other hand, for example, in the prior art shown in FIG. 5B, evaluation is performed by moving one stage of the reference mark 502 to the deflection position of the electron beam by moving the stage.

  According to the present embodiment, it is possible to perform the drift evaluation of the electron beam at the deflection position without moving the stage. Therefore, it is possible to evaluate the drift of the electron beam at the deflection position in a very short time. Therefore, even when drawing is interrupted and electron beam drift evaluation is performed during drawing of an actual mask, the throughput can be reduced to a minimum. Therefore, the drift of the electron beam during writing can be monitored with a minimum decrease in throughput.

(Second Embodiment)
The electron beam drawing method according to the present embodiment includes a deflection sensitivity correction coefficient changing step for changing the deflection sensitivity correction coefficient of the electron beam after the drift amount calculating step and before the second drawing step. This is the same as the first embodiment. Therefore, the description overlapping with the first embodiment is omitted.

  FIG. 6 is a process diagram of the electron beam drawing method of the present embodiment.

  In addition to the first embodiment, after the drift amount calculation step (S150) and before the second drawing step (S170), the electrons are calculated based on the deflection sensitivity correction coefficient calculated from the calculated drift amount. A deflection sensitivity correction coefficient changing step (S162) for changing the deflection sensitivity correction coefficient of the beam is provided. The deflection sensitivity correction coefficient changing step (S162) is executed in a deflection sensitivity correction coefficient changing unit (not shown) provided as an element of the control circuit 150 (FIG. 1).

  Specifically, for example, a process for replacing the conventional correction coefficient with the correction coefficient of (Expression 1) calculated in the deflection sensitivity correction coefficient calculation step (S160) is performed. This makes it possible to maintain the accuracy of the drawing position even if there is an electron beam drift during mask drawing.

  As shown in FIG. 6, a determination step (S161) is provided after the drift amount calculation step (S150) or the deflection sensitivity correction coefficient calculation step (S160) and before the deflection sensitivity correction coefficient change step (S162). The configuration may be such that the deflection sensitivity correction coefficient changing step (S162) is executed only when the drift amount or the fluctuation of the deflection sensitivity correction coefficient exceeds a predetermined threshold.

(Third embodiment)
An evaluation method for an electron beam lithography apparatus according to the present embodiment includes a reference position information acquisition step of irradiating a plurality of reference marks fixed on a stage with an electron beam and acquiring reference position information of each reference mark, and a stage. By comparing the evaluation position information with the reference position information, the evaluation position information acquisition step of sequentially irradiating the reference mark with the electron beam by deflecting the electron beam in a stationary state and acquiring the evaluation position information of each reference mark. A comparison step, and a drift amount calculation step of calculating a drift amount of the beam position in the deflection state of the electron beam from the result of the comparison step. The second embodiment is the same as the first embodiment except that the first drawing step and the second drawing step are not provided. Therefore, the description overlapping with the first embodiment is omitted.

  FIG. 7 is a process diagram of the drawing method of the electron beam drawing apparatus according to the present embodiment. A reference position information acquisition step (S210), an evaluation position information acquisition step (S221), a comparison step (S231), and a drift amount comparison step (S241) are executed.

According to the present embodiment, it is possible to monitor the drift of the electron beam in a short time at the time of starting up the electron beam drawing apparatus or during periodic inspection.
(Fourth embodiment)
The evaluation method of the electron beam lithography apparatus of this embodiment is the same as that of the third embodiment, except that the evaluation position information acquisition process is repeated a plurality of times without interposing the movement of the stage. Therefore, the description overlapping with the third embodiment is omitted.

  FIG. 8 is a process diagram of the evaluation method of the electron beam drawing apparatus according to the present embodiment. In the present embodiment, the evaluation position information acquisition step, the comparison step, and the drift amount comparison step are performed without interposing the movement of the stage (S221), (S231), (S241) to (S22n), (S23n). -It repeats in (S24n) n times (n is a natural number of 2 or more), for example, for a short time of 1 second or less.

  According to the present embodiment, it is possible to evaluate the drift of the electron beam at the deflection position with a high speed time constant. For example, the drift of the electron beam at the deflection position in about 1 to 10 seconds, which could not be detected by the conventional method, can be evaluated.

  The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.

  In addition, although descriptions are omitted for parts and the like that are not directly required for the description of the present invention, such as a device configuration and a control method, a required device configuration and a control method can be appropriately selected and used. In addition, all charged particle beam writing methods, evaluation methods for charged particle beam writing apparatuses, and charged particle beam writing apparatuses that include elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention. .

DESCRIPTION OF SYMBOLS 100 Electron beam drawing apparatus 102 Drawing part 104 Control part 106 Drawing data storage part 110 Sample 132 Sub deflector 134 Main deflector 140 Shot data generation part 150 Control circuit 160 Detector 161 Detection part 162 Reference position information storage part 163 Evaluation position information Storage unit 164 Comparison unit 165 Drift calculation unit 166 Deflection sensitivity correction coefficient calculation unit

Claims (5)

A reference position information acquisition step of irradiating a plurality of reference marks fixed on the stage with a charged particle beam and acquiring reference position information of each of the reference marks;
A first drawing step of irradiating a sample placed on the stage with a charged particle beam and drawing a pattern on the sample;
An evaluation position information acquisition step of sequentially irradiating the reference mark with a charged particle beam by deflecting a charged particle beam while the stage is stationary, and acquiring evaluation position information of each of the reference marks;
A comparison step of comparing the evaluation position information and the reference position information;
A drift amount calculating step of calculating a drift amount of the beam position in the deflection state of the charged particle beam from the result of the comparison step;
A second drawing step of irradiating the sample with a charged particle beam and drawing a pattern on the sample;
A charged particle beam writing method comprising:   2. The deflection sensitivity correction coefficient changing step of changing a deflection sensitivity correction coefficient based on the drift amount after the drift amount calculating step and before the second drawing step. Charged particle beam drawing method. A reference position information acquisition step of irradiating a plurality of reference marks fixed on the stage with a charged particle beam and acquiring reference position information of each of the reference marks;
An evaluation position information acquisition step of sequentially irradiating the reference mark with a charged particle beam by deflecting a charged particle beam while the stage is stationary, and acquiring evaluation position information of each of the reference marks;
A comparison step of comparing the evaluation position information and the reference position information;
A drift amount calculating step of calculating a drift amount of the beam position in the deflection state of the charged particle beam from the result of the comparison step;
A method for evaluating a charged particle beam writing apparatus, comprising:   The charged particle beam drawing apparatus evaluation method according to claim 3, wherein the evaluation position information acquisition step is continuously repeated a plurality of times without interposing the movement of the stage. A reference position information storage unit for storing reference position information of each of the reference marks obtained by irradiating a charged particle beam to a plurality of reference marks fixed on the stage;
An evaluation position information storage unit that stores evaluation position information of each of the reference marks obtained by sequentially irradiating the reference marks with the charged particle beam by deflecting a charged particle beam while the stage is stationary;
A comparison unit for comparing the evaluation position information and the reference position information;
A drift amount calculation unit that calculates a drift amount of a beam position in a deflection state of the charged particle beam from a result of comparison in the comparison unit;
A charged particle beam drawing apparatus comprising:

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