JPH06260401A - Control of deflection of charged particle beam to stencil mask - Google Patents

Abstract

PURPOSE:To project correctly a charged particle beam on a stencil mask as a vertical beam to prevent distortion from being generated in a pattern to be exposed on a sample by a method wherein at the time of a calibration, the stencil mask for calibration formed with a plurality of through hole patterns of the same shape is used. CONSTITUTION:One of through hoe patterns in a stencil mask 12 is made to coincide on an optical axis C and a current IEB of a charged particle beam EB, which is made to pass through an aperture 13, is detected. Then, an emission point of the beam EB on a sample 14 at the time when the beam EB is made to pass through the through hole pattern is taken as an origin SO of the beam EB and an emission position S of the beam EB on the sample 14 is detected. The amounts of driving of a mask incident side deflector ID and a mask emitting side deflector OD are respectively changed about each of the through hole patterns and such the amounts of driving of the deflectors as a potential deviation X of the position S from the origin SO is reduced to the minimum and the detection current IEB is increased to the maximum are found. Thereby, a positional deviation in exposure can be corrected and a positional accuracy of exposure is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a charged particle beam exposure apparatus, in which a charged particle beam passing through the optical axis is swung to pass the charged particle beam perpendicularly to a selected through hole pattern on a stencil mask. After that, the present invention relates to a charged particle beam deflection control method for a stencil mask, in which the charged particle beam is swung back to pass on the optical axis.

[0002]

2. Description of the Related Art With the miniaturization of semiconductor integrated circuits, FIG.
The charged particle beam exposure apparatus as shown in FIG. FIG. 16 shows an ideal optical path of the electron beam EB.

Electron beam EB emitted from electron gun 10
Is collimated through the first A magnetic field lens L1A, shaped into a rectangle through the aperture 11, then converged and diverged through the first B magnetic field lens L1B, and then expanded into a second beam.
It is collimated through the A magnetic field lens L2A and is converged through the second B magnetic field lens L2B.

A stencil mask 12 is arranged between the second A magnetic lens L2A and the second B magnetic lens L2B. The stencil mask 12 is formed with a large number of through-hole patterns that are frequently used. In order to pass the electron beam EB through the selected one passage hole pattern, the mask incident side deflector D1 is arranged between the first B magnetic lens L1B and the second A magnetic lens L2A to swing the electron beam EB. A mask entrance side deflector D2 is arranged at the position of the magnetic field lens L2A, and the traveling direction of the electron beam EB is bent to be parallel to the optical axis C. Then, the second B magnetic field lens L
The mask emission side deflector D3 is arranged at the position of 2B, and the electron beam EB is swung back to the optical axis C side, and the second B magnetic field lens L
2B and a third magnetic field lens (condenser magnetic field lens) L3 below the mask magnetic field exit side deflector D4 bends the traveling direction of the electron beam EB so that the electron beam EB passes on the original optical axis C.

Mask incident side deflectors D1, D2 and second A
The stencil mask 12 includes the magnetic field lens L2A, the mask exit side deflectors D4 and D3, and the second B magnetic field lens L2B.
Are arranged so as to be plane-symmetric with respect to each other. A driving voltage is applied to the mask incident side deflectors D1 and D2 so that the mask incident side deflector D1 and the mask emission side deflector D4 have the same swing amount and swing direction with respect to the electron beam EB. The mask incident side deflectors D1 and D are arranged such that the mask incident side deflector D2 and the mask exit side deflector D3 have the same swing amount and swing direction.
A drive voltage is applied to 2. As a result, the electron beam EB
Is ideally on the optical axis C when exiting the mask emission side deflector D4, regardless of which pass-through pattern on the stencil mask 12.

The electron beam E passing through the third magnetic field lens L3
B is the aperture 13 for angle diaphragm, the fourth magnetic field lens L4
And the sample 14 is converged and irradiated through the fifth magnetic field lens (objective magnetic field lens) L5. The sample 14 is a mask or a semiconductor wafer, and the surface thereof is coated with a resist film.

The magnetic field lenses L1A, L1B, L2A
In order to make it possible to adjust the optical axis of each of the pair of L2B and L2B, and L3 and L4, alignment coils A1A, A1B, A2, A3 and A4 are respectively arranged above them.

According to such a charged particle beam exposure apparatus, a fine pattern can be drawn on the sample 14 with a one-shot electron beam.

[0009]

However, the mask entrance side deflectors D1 and D2 and the second A magnetic field lens L2A and the mask exit side deflectors D4 and D3 and the second B magnetic field lens L2B are completely related to the stencil mask 12. The mask incident side deflectors D1 are not arranged symmetrically with respect to each other, and
The electron beam deflection amount by each of D2 and the mask emission side deflectors D3 and D4 has an error due to the sensitivity of the drive circuit. Therefore, the electron beam EB is actually not necessarily the optical axis C at the position of the third magnetic field lens L3 as shown in FIG.
The exposure position on the sample 14 is displaced without passing over. Further, since the electron beam EB is not accurately perpendicular to the stencil mask 12, the exposure pattern on the sample 14 is distorted. As a result, the drawing pattern becomes inaccurate, which hinders pattern miniaturization.

In view of such problems, an object of the present invention is to provide a charged particle beam deflection control method for a stencil mask, which can draw a pattern more accurately.

[0011]

FIG. 1 is an explanatory view of a charged particle beam deflection control method for a stencil mask according to the present invention.

According to the present invention, the charged particle beam EB passing on the optical axis C is swung by at least one electrostatic or electromagnetic mask incident side deflector ID so that the selected passage hole pattern on the stencil mask 12 is selected. After shaping the cross-sectional shape of the charged particle beam EB through the charged particle beam EB, the charged particle beam EB is swung back by at least one electrostatic or electromagnetic mask emission side deflector OD to obtain the charged particle beam EB.
Of the calibration beam for the stencil mask, in which the beam passes through the optical axis C, and the charged particle beam EB passes through the aperture 13 for angular stop having a hole on the optical axis C. At this time, one center of the through hole pattern on the stencil mask 12 is aligned with the optical axis C, the current I _EB of the charged particle beam EB passing through the aperture 13 is detected, and the sample 14 of the charged particle beam EB is detected. The upper irradiation point position S is detected and the mask incident side deflector I is detected.
D and the amount of deflection of the charged particle beam at the mask emission side deflector OD are set to 0, and the irradiation point on the sample 14 when the charged particle beam EB is passed through the on-axis passage hole pattern on the stencil mask 12 is shown. With the origin S0, the drive amount V of the mask entrance side deflector ID and the mask exit side deflector OD is changed for each of the plurality of passing hole patterns on the stencil mask 12, and the charged particle beam E is applied to the passing hole pattern.
Irradiation point position S on the sample 14 detected when passing B
The deviation V from the origin S0 is minimized, and the deflector drive amount V that maximizes the detected current I _EB is determined. In the actual exposure, the determined deflector drive amount V and the selected deflector drive amount V are selected. The deflector drive amount V is determined based on the position of the passing hole pattern on the stencil mask 12.

According to the calibration of the present invention, it is possible to prevent the charged particle beam EB from being accurately perpendicular to the stencil mask 12 during the actual exposure and causing the exposure pattern on the sample 14 to be distorted. In addition, since the exposure position shift is corrected and the exposure position accuracy is improved, the drawing pattern becomes accurate and the semiconductor integrated circuit pattern can be further miniaturized.

In the first aspect of the present invention, as the stencil mask, a stencil mask having a plurality of through-hole patterns of the same shape formed at the time of calibration is used, for example, as shown in FIG.

With this structure, the effect of calibration for each position on the stencil mask can be easily and accurately confirmed, and the exposure position accuracy can be further improved.

According to the second aspect of the present invention, as a stencil mask, during calibration, for example, as shown in FIG. 8, the width a is narrower than the width of the cross section of the charged particle beam EB, and the length is a cross section of the charged particle beam. A mask incident side deflector ID is used as an angle of the charged particle beam traveling direction with respect to the width direction of the slit SY in the mask incident side deflector ID using a stripe pattern PX in which a plurality of slits SY longer than the width of the EBS are arranged in stripes By changing so that the ratio of the current of the charged particle beam emitted from the stencil mask to the current of the charged particle beam incident on the stencil mask is maximized.

As shown in FIG. 9, the stencil mask 12
When the thickness of B is b and the incident angle of the charged particle beam EB with respect to the stencil mask 12B is θ, the incident angle θ = 0.
The ratio of the current of the charged particle beam emitted from the stencil mask 12B at the incident angle θ to the current of the charged particle beam EB emitted from the stencil mask 12B at this time is (a-btan θ) / a = 1- (b / A) tan
θ. For example, when a = 5 μm and b = 20 μm,
When the incident angle θ deviates by 1 °, the electric current of the charged particle beam emitted from the stencil mask 12B changes by 7%, so that the charged particle beam EB can be vertically incident on the stencil mask with higher accuracy, and the current on the sample 14 can be made higher. It is possible to prevent the exposure pattern from being distorted and accurately draw the pattern on the sample 14.

In the third aspect of the present invention, in order to obtain the deflector drive amount V that minimizes the positional deviation x and maximizes the detected current value I _EB , the absolute value of the positional deviation x is detected by current detection. The deflector drive amount V that minimizes the value divided by the value I _EB is determined.

In the case of this configuration, since it suffices to focus on one variable and perform the calibration, the calibration can be performed more easily.

In the fourth aspect of the present invention, the deflector drive amount V1 for one of the mask incident side deflector ID and the mask output side deflector OD is fixed, and the deflector drive amount V2 for the other is fixed.
Is changed so that the value obtained by dividing the absolute value of the positional deviation x by the current detection value I _EB becomes the minimum, and the deflector drive amount V with respect to the other is
In the first step of obtaining 2 as an approximate value, the deflector drive amount V2 for the other is fixed to the approximate value, and the deflector drive amount V1 for the one is changed to determine the absolute value of the positional deviation x. A second step in which a value obtained by dividing the detected current value I _EB is a minimum, the deflector drive amount V1 for the one is obtained as an approximate value, and the value is set to the fixed value in the first step; By alternately repeating until the approximated values in both the first and second steps converge, the positional deviation x becomes minimum and the current detection value I _EB becomes maximum, and the deflector drive amount V is maximized. Ask for.

By using such an algorithm, calibration can be automated.

In the fifth aspect of the present invention, the mask incident side deflector ID is the first deflector for swinging the charged particle beam EB passing on the optical axis C toward the selected passage hole pattern side on the stencil mask 12. D1 and a second deflector D2 for making the charged particle beam EB shaken by the first deflector D1 parallel to the optical axis C and passing perpendicularly to the passage hole pattern, and the mask emission side deflector OD On the optical axis C, a third deflector D3 for returning the charged particle beam EB that has passed through the passing hole pattern to the optical axis C side, and a charged particle beam EB reflected by the third deflector D3. It has a fourth deflector D4 for passing through.

In the first step, the deflector driving amount V for one of the first deflector D1 and the second deflector D2 is set.
11 is fixed and the deflector drive amount V12 for the other is changed so that the absolute value of the positional deviation x divided by the current detection value I _EB becomes the minimum, and the deflector drive amount V12 for the other is set as an approximate value. The 1A step to be obtained, and then, the deflector drive amount V12 for the other is fixed to the approximate value, and the deflector drive amount V11 for the one is changed to obtain the positional deviation x.
The absolute value of is divided by the current detection value I _EB to obtain the minimum, and the deflector drive amount V11 for the one is obtained as an approximate value,
The 1B step in which the value is the fixed value in the 1A step is alternately repeated until the approximate values in the 1A and 1B steps converge together.

Further, in the second step, the deflector driving amount V for one of the third deflector D3 and the fourth deflector D4 is set.
21 is fixed, and the deflector drive amount V22 for the other is changed so that the value obtained by dividing the absolute value of the positional deviation x by the current detection value I _EB becomes the minimum. The deflector drive amount V22 for the other is set as an approximate value. The second step A to be obtained, and then, the deflector drive amount V22 for the other is fixed to the approximate value, and the deflector drive amount V21 for the one is changed to obtain the positional deviation x.
The value obtained by dividing the absolute value of by the current detection value I _EB is the minimum, and the deflector drive amount V21 for the one is obtained as an approximate value,
The second B step in which the value is the fixed value in the second A step is alternately repeated until the approximate values in the second A and second B steps converge.

Using such an algorithm, the first
Even if the fourth deflector is provided, the calibration can be automated.

In the sixth aspect of the present invention, during calibration, one of the first to fourth deflectors D1 to D4 is driven at a set value, and the charged particle beam upstream of the first deflector D1. by supplying a driving current I _D to the disposed side position the optical axis adjusting alignment coil a, the aperture passing through the current detection value I _EB seek driving current I _D becomes maximum, the one other than the deflector the Similarly, the drive current _ID that maximizes the aperture passing current detection value I _EB is obtained, and the deflection characteristics of each of the first to fourth deflectors are obtained based on the set drive amount and the obtained drive current _ID. .

Then, the charged particle beam EB passes through the selected through hole pattern on the stencil mask 12 perpendicularly to the stencil mask 12, and then is swung back to the optical axis C.
The first to fourth deflector drive amounts for passing over are obtained based on the deflection characteristics, and the first to fourth deflector drive amounts are obtained in the vicinity of the obtained drive amounts.
The displacement x from the origin S0 of the irradiation point position on the sample 14 detected when the charged particle beam EB is passed through the passage hole pattern 12 by changing the driving amount V of the four-deflectors D1 to D4 is minimized, At the same time, the deflector drive amount that maximizes the detected current I _EB is determined.

In the sixth aspect, as described above, the deflector D1 is used.
Since the characteristics of D4 to D4 are taken into consideration, the number of repetitive processes until the positional deviation x is minimized and the detected current I _EB is maximized can be reduced, and the time required for calibration can be shortened. You can

In the seventh aspect of the present invention, the charged particle beam EB is used for the stencil mask 1 during the calibration.
The first deflector D1 and the second deflector D2 are driven so as to pass through the selected passage hole pattern on 2, and the driving amount is fixed.

Then, in this state, the charged particle beam EB which has passed through the passing hole pattern is swung back and passes substantially on the optical axis C, passes through the aperture 13, and the aperture passing current detection value I _EB becomes maximum. At this time, two or more sets of the driving amount of the third deflector D3, the driving amount of the fourth deflector D4, and the irradiation point position of the charged particle beam EB on the sample 14 are obtained, and the obtained two or more sets of the third A relational expression between the third deflector drive amount, the fourth deflector drive amount, and the irradiation point position is approximately determined from the deflector drive amount, the fourth deflector drive amount, and the irradiation point position. From the relational expression, the third deflector driving amount and the fourth deflector driving amount at which the irradiation point position is the origin are obtained.

According to the seventh aspect, since the third deflector drive amount and the fourth deflector drive amount with the irradiation point position as the origin are estimated as described above, the positional deviation x is minimized and detected. It is possible to reduce the number of times of repeated processing until the current I _EB reaches the maximum, and it is possible to further reduce the time required for calibration.

[0032]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] The optical system of the electron beam exposure apparatus is the same as that shown in FIGS. 16 and 1
In FIG. 7, the deflectors D1 to D4 only in the X direction are shown, but the electron beam exposure apparatus is provided with the same pattern selecting deflector also in the X direction and the Y direction perpendicular to the direction of the optical axis C. . An unillustrated exposure position scanning deflector (main deflector and sub deflector) is also provided at the position of the fifth magnetic field lens L5. The sample 14 is mounted on a moving stage (not shown).

When the exposure position shift occurs, the electron beam E
Since B is obliquely incident on the aperture 13 for angle diaphragm as shown in FIG. 17, as compared with the case where the electron beam EB is incident on the aperture 13 perpendicularly through the optical axis C as shown in FIG. The current passing through the aperture 13 decreases. To measure this current, a current detector 15 is connected between the calibration sample 14 and the ground line.

Further, in order to detect the exposure position on the sample 14, backscattered electron detectors 16A and 16B are arranged obliquely above the sample 14.

A calibration stencil mask 12A as shown in FIG. 3 is used to obtain the correction value of the electron beam deflection amount by the mask entrance side deflectors D1 and D2 and the mask exit side deflectors D3 and D4. On the calibration stencil mask 12A, pass-hole patterns P11 to P55 having the same shape are formed in a grid pattern. Through hole pattern P33 located in the center
In the illustrated XY orthogonal coordinate system with the center of the origin as the origin, the center coordinates of the passage hole pattern Pij are defined as (Xi, Yj). The center coordinates (Xi, Yj) are the stencil masks 12 that are actually used in this embodiment for the sake of simplification of description.
It is assumed that the coordinates of the center of the upper hole pattern match.

The electron beam exposure apparatus has an electron beam deflection control circuit as shown in FIG. For simplification of the description, the deflector D in the figure represents the deflectors D1 to D4, and in reality, the constituent elements 23 to 28 are the deflectors D1 to D4.
Prepared for D4. Further, in FIG. 2, the current detector 15, the A / D converter 17, the microcomputer 1
8 and the address register 21, only the configuration relating to the X-direction deflection control is shown, but the Y-direction deflection control has the same configuration as the X-direction deflection control.

The output of the current detector 15 is the A / D converter 1
7 is supplied to the microcomputer 18 as an electron beam current I _EB , and the outputs of the backscattered electron detectors 16A and 16B are supplied to the microcomputer 18 as a backscattered electron detection amount I _R via a summing amplifier 19 and an A / D converter 20. To be done. The microcomputer 18 has a normal configuration including a CPU, a program storage ROM, a work RAM, and an I / O port.

The microcomputer 18 selects a passage hole pattern Pij for the passage hole pattern selection address Ai.
j is supplied to the address register 21 and held therein. In the passage hole pattern selection address Aij, for example, the upper bit represents i and the lower bit represents j. This i is supplied to the passage hole pattern X coordinate memory 22, and the center X coordinate Xi of the passage hole pattern Pij stored at the address i is read from the passage hole pattern X coordinate memory 22. X
i is supplied to one input terminal of the adder 23. On the other hand,
The passage hole pattern selection address (i, j) is supplied to the address input terminal of the deflection value correction memory 24, and the correction value Cij stored in this address is read out. At the time of actual exposure, the adder is added via the selector 25. 23 is supplied to the other input terminal. The output Xi + Cij of the adder 23 is D /
It is supplied to the A converter 26, converted into an analog voltage, and supplied to the driver 27. The driver 27 applies the drive voltage VXij proportional to the input voltage (may be non-linear) to the deflector D, for example. As a result, an electric field EXij is formed between the pair of deflectors D.

The selector 25 has a count value k of the counter 28.
Is also supplied, and the microcomputer 18 selects the selector 25.
On the other hand, the input end on the deflection value correction memory 24 side is selected at the time of actual exposure, and the input end on the counter 28 side is selected at the time of automatically setting the exposure position deviation correction value.

At the time of automatically setting the exposure position deviation correction value, the microcomputer 18 loads the counter 28 with the initial value -ε and supplies the clock CK to the counter 28 to increment the count value k. When the microcomputer 18 determines the correction value Cij corresponding to the passage hole pattern selection address Aij as described later, the microcomputer 18 writes Cij in the address Aij of the deflection value correction memory 24.

In this embodiment, the deflection value correction memory 24 is addressed by (Xi, Yj) in order to correct the exposure position deviation with higher accuracy.
, The deflection value correction memory 24 is addressed only by X, and the deflector D in the Y direction is addressed by the deflection value correction memory 24 only by Yj. The effect of the invention can be obtained.

Next, the procedure for automatically setting the exposure position deviation correction for the deflection value correction memory 24 will be described with reference to FIG. Hereinafter, the numerical value in the parenthesis represents the step identification number in the figure.

(30) The driving voltage for the deflectors D1 to D4 is set to 0V, that is, i = j = 3, X3 =
With Y3 = ε = k = 0, the through-hole pattern P located at the center on the calibration stencil mask 12A.
The position of the irradiation point S33 of the undeflected electron beam on the sample 14 when the electron beam EB is passed through 33 is detected as follows.

On the sample 14 for calibration,
An L-shaped mark 14a as shown in FIG. 6 (A) is formed. The sample 14 is arranged such that the L-shaped mark 14a is located near the intersection of the optical axis C and the surface of the sample 14, and one side of the L-shaped mark 14a is parallel to the X-axis direction. The center lines of the two sides of the L-shaped mark 14a are defined as the Lx axis and the Ly axis, respectively.

The L-shaped mark 14a has a concave cross section, and the backscattered electron detection amount I _{R is} obtained when the electron beam EB is swung in a direction parallel to the Lx axis by an exposure position scanning deflector (not shown).
Is as shown in FIG. The microcomputer 18 differentiates the reflected electron detection amount I _R to detect the position of the positive and negative peaks Lx1 and Lx2 as shown in FIG. 6 (C), the center positions of the peaks (Lx1 + Lx2) / 2 L
The Lx coordinate Lx33 of the irradiation point S33 when the deflection amount by the exposure position scanning deflector is 0, which is the origin of the x-axis, is obtained.

Next, the electron beam EB is swung in the direction parallel to the Ly axis by the above-mentioned exposure position scanning deflector, and Ly of the irradiation point S33 when the deflection amount by the exposure position scanning deflector is 0 in the same manner as above. The coordinate Ly33 is obtained.

In the following, irradiation point S33 (Lx33,
Let x be the axis passing through Ly33) and parallel to the Lx axis, and the irradiation point S
An axis passing through 33 (Lx33, Ly33) and parallel to the Ly axis is y.

(31) Pass hole pattern Pij (i, j =
1 is assigned to the identification variables i and j of 1 to 5).

(32) The preferable count value k obtained previously for each of the mask entrance side deflector D2, the mask exit side deflectors D3 and D4 is loaded into the counter 28, and the mask entrance side deflector D2 and the mask exit side are deflected. The voltage applied to the side deflectors D3 and D4 is fixed. In this state, the sample 14 is irradiated with the electron beam EB, and the count value k of the mask incident side deflector D1 is changed in the range of −ε to ε, or before and after the preferable count value k obtained last time. , And a preferable count value k = C1ij for the mask incident side deflector D1 is changed.
Is calculated as described below. This value C1ij is loaded into the counter 28 corresponding to the mask entrance side deflector D1 and the applied voltage to the mask entrance side deflector D1 is fixed. In this state, next, the electron beam EB is irradiated onto the sample 14, and the count value k of the mask entrance side deflector D2 is -ε to ε.
The desired count value k = C2ij for the mask entrance side deflector D2 is calculated as described below by changing the value in the range of (1) or before and after the preferable count value k calculated last time. This value C2ij is loaded into the counter 28 corresponding to the mask entrance side deflector D2 to fix the applied voltage to the mask entrance side deflector D2.

(33) The counter 28 is loaded with the preferable count value k obtained previously for each of the mask entrance side deflectors D1 and D2 and the mask exit side deflector D4 to load the mask entrance side deflectors D1 and D2 and the mask. The sample 14 is irradiated with the electron beam EB while the applied voltage of the exit side deflector D4 is fixed, and the count value k of the mask exit side deflector D3 is changed in the range of −ε to ε, or Then, the preferable count value k = C3ij for the mask emission side deflector D3 is obtained by changing it before and after the previously obtained preferable count value k as described later. This value C3ij is loaded into the counter 28 corresponding to the mask emission side deflector D3 to fix the applied voltage to the mask emission side deflector D3. Next in this state
By irradiating the sample 14 with the electron beam EB and changing the count value k with respect to the mask emission side deflector D4 in the range of −ε to ε, a preferable count value k = C4ij for the mask emission side deflector D4 will be described later. To ask. This value C
4ij is a counter 2 corresponding to the mask output side deflector D4
Then, the voltage applied to the mask emission side deflector D4 is fixed.

(34) The preferable correction values C1ij, C2ij, C3ij and C obtained in steps 32 and 33 above.
It is determined whether all 4ij have converged. That is, it is determined whether the absolute value of the difference between the correction value obtained last time and the correction value obtained this time is less than or equal to a small set value. 1
If even one has not converged, the process returns to step 32, and if all have converged, the process proceeds to the next step 35.

(35) Mask incident side deflectors D1, D2,
For each of the mask emission side deflectors D3 and D4, the converged correction value is set to the address (i,
j).

(36) Increment j. As a result, when j = 6, i is incremented by
Also, j = 1.

(37) If i ≦ 5, the above step 32
Then, if i> 5, the process ends.

Next, the preferable count value k for each of the mask entrance side deflectors D1 and D2 and the mask exit side deflectors D3 and D4, which is performed in steps 32 and 33 above.
The method of obtaining the above will be described with respect to the deflector D. It is assumed that the address register 21 holds (i, j).

(40) The counter 28 is loaded with an appropriate constant −ε which enables the minimum value to be obtained in the following step 45, and the count value k = −ε. As a result, the output of the adder 23 becomes Xi-ε.

(41) The electron beam EB is emitted from the electron gun 10 and passed through the passage hole pattern Pij, and the position Lxij of the irradiation point Sij shown in FIG. 6A is detected in the same manner as in step 30 above, and xij = Lxij-Lx33 is obtained, and the electron beam current I _EB is detected.

(42) Calculate | xij | / I _EB . The exposure position accuracy is higher as the value of | xij | is smaller and the value of I _EB is larger.

(43) If k <ε, the next step 44
Go to step 45 if k ≧ ε.

(44) One clock CK, counter 2
8, the count value k is incremented, and the process returns to step 41.

(45) | xij obtained as above
| / I _EB is as shown in FIG. 7, for example, and the value of the count value k corresponding to the minimum value is obtained as the preferable correction value Cij.

By the above processing, each position (Xi, Y) on the calibration stencil mask 12A is
The exposure position deviation correction value for the passage hole pattern Pij of j) is automatically set in the deflection value correction memory 24. After this setting, the stencil mask 12 is used to actually
A fine pattern can be accurately drawn by drawing the pattern on the top.

[Second Embodiment] Next, a second embodiment of the present invention will be described.

FIG. 8 shows striped patterns PX and PY formed on the calibration stencil mask.

In the striped pattern PX, a plurality of slits SY whose longitudinal direction is the Y direction in the drawing are arranged in parallel with each other at a constant pitch in the X direction shown in the drawing which is perpendicular to the Y direction. Similarly, in the striped pattern PY, a plurality of slits SY whose longitudinal direction is the X direction are arranged in parallel in the Y direction at a constant pitch. The widths a of the slits SX and SY are narrower than the width of the cross section EBS of the electron beam, and the lengths thereof are longer than the width of the cross section EBS of the electron beam. For example, the cross section EBS is 20 μm ×
It is 20 μm, and the slit width a is 5 μm. Such striped patterns PX and PY are formed instead of the through hole patterns P11 to P55 of the calibration stencil mask 12A of FIG. 3, for example.

As shown in FIG. 9, assuming that the thickness of the calibration stencil mask 12B is b and the incident angle of the electron beam EB with respect to the stencil mask 12B is θ, the light is emitted from the stencil mask 12B when the incident angle θ = 0. The electron beam E emitted from the stencil mask 12B at an incident angle θ with respect to the current of the electron beam EB
The ratio of the current of B is (a-btan θ) / a = 1- (b
/ A) tan θ.

From this equation, it is preferable to increase the aspect ratio b / a as much as possible because the change of the passing current with respect to the change of the incident angle θ becomes large, and therefore the calibration accuracy is improved. Actually, for convenience of mask fabrication, aspect b
/ A is about 4, for example, a = 5 μm and b = 20 μm. In this case, if the incident angle θ shifts by 1 °, the current of the electron beam emitted from the stencil mask 12B changes by 7%. Since the current fluctuation rate of the incident electron beam EB to the stencil mask is about 1%, the current fluctuation rate with respect to the change of the incident angle θ is this level, which is sufficient for the calibration.

As shown in FIG. 8, the cross section EBS of the electron beam is shown.
By increasing the number of slits SY or SX entering inside, the current passage ratio is increased, the SN ratio of the detected current is improved, and even if the position on the stencil mask 12B of the cross section EBS is slightly shifted, it is passed by this. The fluctuation of the current value can be ignored.

Using the stencil mask on which the striped patterns PX and PY are formed, the same processing as in the first embodiment is performed, and the electron beam is passed through the striped pattern PX in step 32 of FIG. The correction value is obtained by changing the deflection amount in the X direction, the electron beam is passed through the striped pattern PY, and the deflection amount in the Y direction is changed to obtain the correction value.

As a result, the electron beam can be vertically incident on the stencil mask with higher accuracy, distortion can be prevented from occurring in the exposure pattern on the sample, and the pattern can be accurately drawn on the sample. Become.

[Third Embodiment] In the first embodiment, when the correction value Cij is obtained, the deflection amount is within a range of ± ε centering on Cij = 0 without considering the characteristics of the deflectors D1 to D4. Since it is changed, the number of repetitions of steps 32 and 34 of FIG. 4 and the number of repetitions of steps 41 to 44 of FIG. 5 executed in steps 32 and 33 until the correction value converges become relatively large, which is necessary for calibration. Time will increase.

Therefore, in order to solve this problem in the third embodiment, the characteristics of the deflectors D1 to D4 are obtained in advance, the correction value C0ij is estimated based on this, and this is used as the deflection value correction memory of FIG. It writes in 24. Then, an adder is used instead of the selector 25, and at the time of calibration, the sum of the correction value C0ij from the deflection value correction memory 24 and the count value k of the counter 28 is supplied to the adder 23, and is calculated by the clock CK. By changing the numerical value k in the range of −ε to ε,
A preferable count value k is obtained in the same manner as in the first embodiment,
The correction value Cij = C0ij + k is determined, and the correction value C0ij in the deflection value correction memory 24 is updated to Cij.

Since the estimated correction value C0ij is used in this embodiment, the value of ε can be made smaller than that of the first embodiment.

At the time of actual exposure, the gate (not shown) is closed to stop the supply of the clock CK to the counter 28, and the count value k of the counter 28 is set to zero.

The other points are the same as those of the first or second embodiment.

Next, how to obtain the characteristic values of the deflectors D1 to D4 and the estimated correction value C0ij will be described.

As shown in FIG. 10, when the constant voltage VX0 is applied only to the deflector Di (i is one of 1 to 4) among the deflectors D1 to D4, the locus of the electron beam EB is as shown by Ti. As a result, the current cannot pass through the aperture 13 and the current detected by the current detector 15 becomes zero. In the figure, the alignment coil A is any of the alignment coils A1A, A1B, or A2 arranged above the deflector D1 in FIG. 16, for example, the alignment coil A1A.

As shown in FIG. 11, with the set voltage applied only to the deflector D1, a drive current is supplied to the alignment coil A so that the locus T5 of the electron beam EB passes through the center of the aperture 13. . The X-direction drive current I _X = I _X1 and the Y-direction drive current I _Y = I _Y1 to the alignment coil A at this time are obtained as characteristic values of the deflector D1. I _X1 and I _Y1 are drive currents I _X0 for causing the electron beam EB to pass through the center of the aperture 13 in the ideal case.
When the drive currents I _X and I _Y are changed little by little before or after I _Y0 = 0, or when changed by the bisection method, the current detector 1
It can be obtained as the drive currents I _X and I _Y when the detected current by 5 becomes maximum.

Compared with changing the combination of the voltages applied to the four deflectors D1 to D4 as in the process of FIG. 4, this process requires changing only the current flowing through the alignment coil A. It's easy.

Note that, unlike the first embodiment, the current detector 1
Backscattered electron detectors 16A and 16
Since B is not used, a Faraday cup is placed on a moving stage (not shown) on which the sample 14 is mounted, and the current detector 15 is connected between this and the ground line to drive the moving stage. Faraday cup with aperture 1
It is possible to more accurately detect the current passing through the aperture 13 by locating the electron beam EB directly below the hole 3 and detecting the current.

FIGS. 12A to 12D are for maximizing the aperture passing current in the state where the set voltage is applied only to the deflector D1, only the deflector D2, only the deflector D3 and only the deflector D4. Alignment coil drive current (I
_Xi , I _Yi ) and i = 1 to 4 are shown. In reality, the deflector D1
Similarly, for the Y-direction deflector paired with each of D4 to D4, the alignment coil drive current showing the characteristic is similarly obtained.

From this set voltage and drive current, the deflector D
The relationship between the actual deflection characteristics (deflection intensity and deflection direction) of 1 to D4 and the designed deflection characteristics is obtained. That is, in consideration of an error in the deflector mounting position, an error in sensitivity including the drive amplifier of the deflector, and the like, the voltage that should be actually applied to the deflector in order to deflect the electron beam EB by a predetermined amount and the voltage applied by design are applied. The relationship with the power voltage is represented by, for example, a primary conversion formula for deflection in the X direction and the Y direction.

Then, in order to make the locus of the electron beam EB as shown in FIG. 16, a voltage to be applied to the deflectors D1 to D4 by design is obtained, and this is substituted into the first-order conversion formula to deflect the deflectors D1 to D1. A voltage to be actually applied to D4 is obtained, and a value proportional to the difference between the voltage to be actually applied and the voltage to be applied in design (the proportional constant is the reciprocal of the amplification factor of the driver 27 in FIG. 2) is estimated and corrected. The value C0ij is stored in the deflection value correction memory 24.

In the third embodiment, as described above, the deflector D
Since the characteristics of 1 to D4 are taken into consideration, the number of repetitions of steps 32 and 34 of FIG. 4 until the correction value converges and step 41 of FIG. 5 executed in steps 32 and 33.
The number of repetitions of ~ 44 can be reduced, and the time required for calibration can be shortened as a whole.

[Fourth Embodiment] In the first embodiment, | x
The correction value Cij that minimizes ij | / I _EB was obtained. However, after maximizing the detection current I _EB by the current detector 15, by minimizing the position deviation | xij | of the electron beam irradiation point on the sample, It is also possible to obtain the correction value Cij, and this method will be described as a fourth embodiment.

The fact that the detection current I _EB becomes maximum means that
As shown in FIG. 13, it means that the electron beam EB passes perpendicularly to the stencil mask 12B and that the cross-sectional center of the electron beam EB coincides with the center of the hole of the aperture 13.

FIG. 15 shows a procedure which is processed instead of steps 32 and 33 of FIG.

(50) The value of the preferable count value k obtained last time for each of the deflectors D2, D3 and D4 (k =
0) is loaded into the counter 28 to fix the applied voltage to the deflector D2, the deflectors D3 and D4. In this state, the sample 14 is irradiated with the electron beam EB, and the deflector D1
The count value k is changed in the range of −ε to ε to obtain the count value k at which the detection current I _EB becomes maximum, and this value is determined by the deflector D.
The counter 28 corresponding to 1 is loaded and the applied voltage of the deflector D1 is fixed. In this state, next, the electron beam EB is irradiated onto the sample 14, and the count value k with respect to the deflector D2 is changed in the range of −ε to ε, and the count value k at which the detection current I _EB becomes maximum is obtained. The obtained value is loaded into the counter 28 corresponding to the deflector D2 and the applied voltage to the deflector D2 is fixed.

(51) Substitute 1 for n.

(52) Regarding the deflector D3, for example, k = 2
The voltage applied to the deflector D3 is fixed as n-3. Let k obtained for the deflector D3 (X-direction deflector) be the X component,
A vector having k as the Y component, which is obtained with respect to the Y-direction deflector (not shown) forming a pair with the deflector D3, is represented by d3.

(53) The sample 14 is irradiated with the electron beam EB, and the count value k of the deflector D4 is changed within the range of -ε to ε, or changed before and after the previously obtained preferable count value k. Then, the count value k at which the detection current I _EB becomes maximum
Is obtained, and this value is loaded into the counter 28 corresponding to the deflector D4 to fix the voltage applied to the deflector D4. Deflector D
4 (X-direction deflector), and k obtained with respect to the Y-direction deflector (not shown) forming a pair with the deflector D4, where k is the X component.
The correction vector having Y as the component is represented by d4.

(54) When the sample 14 is irradiated with the electron beam EB in this state, the trajectory of the electron beam EB becomes, for example, T6 in FIG. The coordinates of the electron beam irradiation point Sn on the sample 14 at this time are obtained in the same manner as in the first embodiment. The coordinate system is the same as the xy orthogonal coordinate system in FIG. 6, and the position vector of the irradiation point Sn is represented by rn.

(55, 56) If n ≠ 2, n is incremented and the process returns to step 52. If n = 2, the process proceeds to the next step 57. The trajectory of the electron beam in step 54 when n = 2 is, for example, T7 in FIG.

(57) The vector rn is replaced with the correction vector dn
Linear function rn = f (dn3, dn4) of 3 and the correction vector dn4
Is approximated by. Formula r1 = f (d13, d14) and formula r2 = f (d
23, d24) and the linear function f is determined. f (d3, d4)
The correction vectors d3 and d4 for which = 0 are obtained, and the preferable count value k is determined by using the correction vectors d3 and d4 as the correction vectors for the deflectors D3 and D4, respectively.

The fourth embodiment can be combined not only with the first embodiment described above but also with any of the second embodiment or the third embodiment described above.

According to the fourth embodiment, since the applied voltage to the deflectors D3 and D4 whose origin is the irradiation point is estimated, the repetitive processing can be further reduced as compared with the third embodiment, and the calibration is required. The time can be shortened.

The present invention includes various modifications other than the above.

For example, the correction values are obtained only for some of the through hole patterns on the calibration stencil mask 12A, and for the stencil mask 12 that is actually used, the interpolation values are used to calculate the through hole pattern positions. It may be configured to obtain the correction value corresponding to. Therefore, the center position of the passage hole pattern on the calibration stencil mask 12A and the position of the passage hole pattern on the stencil mask 12 actually used do not necessarily have to match. In this case, the voltage applied to the deflector may be corrected by, for example, determining the relationship between the voltage that should be actually applied to the deflector and the voltage that is to be applied by design in order to deflect the electron beam EB by a predetermined amount as X.
The deflection in the Y direction and the Y direction is expressed by a primary conversion equation, and the voltage to be applied by design is first converted into the voltage to be actually applied.

Instead of using a stencil mask dedicated to calibration, a stencil mask used for exposure may have a calibration through-hole pattern arranged therein.

The value of ε may be decreased each time the correction value converges.

Of course, the voltages applied to the deflectors D1 to D4 when obtaining the alignment coil drive current in FIG. 12 may be different values for the deflectors D1 to D4.

After step 57 in FIG. 57, the count value k obtained in step 57 for the deflectors D3 and D4 is set, and the electron beam EB is irradiated onto the sample 14 so that the electron beam irradiation point is actually It is confirmed whether the electron beam irradiation point is the origin of the xy coordinates. If the electron beam irradiation point is deviated by more than the allowable value, the count value k is changed before and after this so that the electron beam irradiation point is actually the xy coordinate. You may make it obtain | require the count value k used as an origin.

In some cases, step 3 in FIG.
The processing of steps 32 and 33 or the processing of FIG. 15 may be executed only once without performing the convergence determination in step 4. In particular, when the method of the second and third embodiments is used to implement the fourth embodiment, it can be expected that the configuration of FIG. 15 is executed only once.

[0105]

As described above, according to the calibration of the present invention, during the actual exposure, the exposure position shift is corrected, the exposure position accuracy is improved, and the excellent effect that the drawing pattern is accurate can be obtained. This greatly contributes to miniaturization of the semiconductor integrated circuit pattern.

In the first aspect of the present invention, as the stencil mask, the calibration stencil mask in which a plurality of through-hole patterns of the same shape are formed is used at the time of calibration. Therefore, the calibration for each position on the stencil mask is performed. The effect of can be confirmed easily and accurately, and the exposure position accuracy can be further improved.

In the second aspect of the present invention, the rate of change in current of the charged particle beam emitted from the stencil mask with respect to the change in the angle of incidence of the charged particle beam on the stencil mask is relatively large. It is possible to make the mask vertically incident on the mask, prevent distortion of the exposure pattern on the sample, and accurately draw the pattern on the sample.

In the third aspect of the present invention, the absolute value of the positional deviation is divided by the detected current value in order to obtain the deflector driving amount that minimizes the positional deviation with respect to the origin and maximizes the aperture passing current. Since the deflector drive amount that minimizes the calculated value is obtained, it suffices to carry out the calibration by focusing on one variable, and it is possible to perform the calibration more easily.

By using the algorithm of the fourth aspect of the present invention, it is possible to automate the calibration.

By using the algorithm of the fifth aspect of the present invention, it is possible to automate the calibration even when the first to fourth deflectors are provided.

In the sixth aspect of the present invention, since the characteristics of the deflector are taken into consideration, the positional deviation of the charged particle beam irradiation point on the sample is minimized and the repetition is repeated until the aperture passage detection current becomes maximum. The number of processes can be reduced, and the time required for calibration can be shortened.

In the seventh aspect of the present invention, since the third deflector driving amount and the fourth deflector driving amount whose origin is the charged particle beam irradiation point on the sample are estimated, the positional deviation of the irradiation point is minimized. In addition, it is possible to reduce the number of repeated processes until the aperture passing detection current becomes maximum, and it is possible to further reduce the time required for calibration.

[Brief description of drawings]

FIG. 1 is a principle explanatory diagram of an electron beam deflection control method for a stencil mask according to the present invention.

FIG. 2 is an electron beam deflection control circuit diagram of the first embodiment of the present invention.

FIG. 3 is a plan view of a stencil mask for calibration.

FIG. 4 is a schematic flowchart showing a procedure for automatically setting an exposure position deviation correction value.

5 is a flowchart showing a procedure for approximately obtaining a correction value, which is executed in steps 32 and 33 of FIG.

FIG. 6 is an explanatory view of an electron beam irradiation point position detection method.

FIG. 7 is a diagram showing how to obtain a preferable correction value Cij.

FIG. 8 is a stripe pattern diagram formed on a calibration stencil mask according to the second embodiment of the present invention.

9 is a diagram showing a relationship between an electron beam incident angle θ and a passing current with respect to the striped pattern of FIG.

FIG. 10 relates to a third embodiment of the present invention and relates to deflectors D1 to D.
FIG. 6 is a diagram showing an electron beam trajectory when a voltage is applied to only one of the four.

FIG. 11 is a diagram showing an electron beam locus when a current is supplied to the alignment coil A and an electron beam is passed through the aperture while voltage is applied only to the deflector D1 among the deflectors D1 to D4. .

FIG. 12 is a deflector characteristic diagram showing an alignment coil drive current for maximizing the aperture passing current in a state where the same voltage is applied to only one of the deflectors D1 to D4.

FIG. 13 is a diagram showing an electron beam locus at which the aperture passing current becomes maximum according to the fourth example of the present invention.

FIG. 14 is a diagram showing two electron beam trajectories for maximizing the aperture passing current with the voltage applied to the deflectors D1 and D2 fixed.

15 is a flowchart showing an exposure position deviation correction value automatic setting procedure that is processed instead of steps 32 and 33 of FIG. It is a figure.

FIG. 16 is an optical system diagram of an electron beam exposure apparatus.

FIG. 17 is an optical system diagram of an electron beam exposure apparatus.

[Explanation of symbols]

10 electron gun 11, 13 aperture 12, 12A, 12B stencil mask 14 sample 14a L-shaped mark 15 current detector 16A, 16B backscattered electron detector 17, 20 A / D converter 18 microcomputer 19 summing amplifier 23 adder 24 deflection Value correction memory 28 Counter EB Electron beam C Optical axis L1A, L1B, L2A, L2B, L3, L4, L5
Magnetic field lens D1, D2 Mask entrance side deflector D3, D4 Mask exit side deflector P11-P55 Pass hole pattern A, A1A, A1B, A2, A3, A4 Alignment coil PX, PY Striped pattern SX, SY slit T1-T7 Electron beam trajectory

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Takemoto 2-1844-2, Kozoji-cho, Kasugai-shi, Aichi Prefecture Fujitsu Viels-E Co., Ltd. In-house (72) Inventor Kiichi Sakamoto 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Fujitsu Limited

Claims (8)

[Claims] 1. A charged particle beam (E) passing on an optical axis (C).
B) is shaken by a mask incident side deflector (ID) to shape the cross-sectional shape of the charged particle beam through the charged particle beam with respect to the selected passage hole pattern on the stencil mask (12), and then the charged particle beam Is turned back by a mask emission side deflector (OD) to allow the charged particle beam to pass on the optical axis, and an aperture (13) for an angle diaphragm having a hole on the optical axis for the charged particle beam. Is a method of controlling the deflection of a charged particle beam with respect to a stencil mask, wherein one of the through hole patterns on the stencil mask is aligned with the optical axis during calibration, and the beam passes through the aperture. detecting a current (I _EB) of the charged particle beam to detect the sample (14) on the irradiation point position (S) of the charged particle beam, at the mask incident side deflectors and the mask exit side deflector The deflection point of the charged particle beam is set to 0, and the irradiation point on the sample when the charged particle beam is passed through the on-axis passage hole pattern on the stencil mask is the origin (S0). When the charged particle beam is passed through the passing hole pattern by changing the drive amount (V) of the mask entrance side deflector and the mask exit side deflector for each of the above plurality of passing hole patterns. The displacement amount (x) of the irradiation point on the sample detected from the origin is minimized, and the deflector drive amount is determined such that the detected current is maximized. At the time of actual exposure, Based on the obtained deflector drive amount and the selected through hole pattern position on the stencil mask,
A charged particle beam deflection control method for a stencil mask, characterized in that the deflector drive amount is determined. 2. The charged particles for a stencil mask according to claim 1, wherein the stencil mask is a stencil mask having a plurality of through-hole patterns of the same shape formed during the calibration (12A). Beam deflection control method. 3. As the stencil mask, a plurality of slits having a width narrower than a width of a cross section of the charged particle beam and a length longer than a width of a cross section of the charged particle beam are arranged in a stripe pattern during the calibration. Using a striped pattern formed as the passage hole pattern, and changing the angle of the charged particle beam advancing direction with respect to the width direction of the slit by the mask entrance side deflector to make the charge incident on the stencil mask. Characterized in that the ratio of the current of the charged particle beam emitted from the stencil mask to the current of the particle beam is maximized.
A charged particle beam deflection control method for a stencil mask according to claim 1. 4. The absolute value of the displacement is obtained in order to obtain the deflector drive amount (V) such that the displacement (x) is minimized and the detected current value (I _EB ) is maximized. 4. The charged particle beam deflection control method for a stencil mask according to claim 2, wherein the deflector drive amount that minimizes a value obtained by dividing the current detection value by is calculated. 5. A deflector drive amount (V1) for one of the mask entrance side deflector (ID) and the mask exit side deflector (OD) is fixed, and a deflector drive amount (V) for the other is fixed.
2) is changed so that the value obtained by dividing the absolute value of the positional deviation (x) by the current detection value (I _EB ) becomes the minimum, and the deflector drive amount for the other is obtained as an approximate value. Next, the deflector drive amount (V2) for the other is fixed to the approximate value, the deflector drive amount (V1) for the one is changed, and the absolute value of the positional deviation is detected by the current detection. And a second step in which the deflector drive amount for the one is calculated as an approximate value and the value is set to the fixed value in the first step. It is characterized in that the deflector drive amount that minimizes the positional deviation and maximizes the current detection value is obtained by alternately repeating the two steps until the approximate values converge together. Charged particle beam polarization for the stencil mask of claim 4, Control method 6. The mask incident side deflector (ID) swings a charged particle beam (EB) passing on the optical axis (C) to the selected passage hole pattern side on the stencil mask (12). First deflector (D1) and a second deflector (D) for making the charged particle beam oscillated by the first deflector parallel to the optical axis and passing it perpendicularly to the passage hole pattern.
2), the mask emission side deflector (OD) includes a third deflector (D3) for returning the charged particle beam that has passed through the passage hole pattern to the optical axis side, and the third deflector (D3). A fourth deflector (D4) for passing the charged particle beam reflected by the three deflectors on the optical axis, wherein the first step includes the first deflector or the second deflector. The deflector drive amount (V11) for one of the positions is fixed, and the deflector drive amount (V12) for the other is changed so that a value obtained by dividing the absolute value of the positional deviation by the current detection value becomes the minimum. 1A step for obtaining the deflector drive amount for the other as an approximate value, and then fixing the deflector drive amount (V12) for the other to the approximate value, and setting the deflector drive amount for the one (V1
1) is changed so that the value obtained by dividing the absolute value of the positional deviation by the detected current value becomes the minimum, the deflector drive amount for the one is obtained as an approximate value, and the value is calculated in the step 1A. The first step B with the fixed value is alternately repeated until the approximate values in the first step A and the first step B are converged, and the second step includes the third deflector or the fourth deflector. The deflector drive amount (V21) for one of the devices is fixed, and the deflector drive amount (V22) for the other device is changed so that the absolute value of the positional deviation divided by the detected current value becomes the minimum. A second step A for obtaining the deflector drive amount for the other as an approximate value, and then fixing the deflector drive amount (V22) for the other to the approximate value, and setting the deflector drive amount (V2 for the one
1) is changed so that the value obtained by dividing the absolute value of the positional deviation by the detected current value becomes the minimum, and the deflector drive amount for the one is obtained as an approximate value, and the value in the second A step is calculated. 6. The charged particle beam for a stencil mask according to claim 5, wherein the 2B step of setting the fixed value is alternately repeated until the approximation values in the 2A and 2B steps converge together. Deflection control method. 7. The mask incident side deflector (ID) swings a charged particle beam (EB) passing on the optical axis (C) to the selected passage hole pattern side on the stencil mask (12). First deflector (D1) and a second deflector (D) for making the charged particle beam oscillated by the first deflector parallel to the optical axis and passing it perpendicularly to the passage hole pattern.
2), the mask emission side deflector (OD) includes a third deflector (D3) for returning the charged particle beam that has passed through the passage hole pattern to the optical axis side, and the third deflector (D3). A third deflector is provided with a fourth deflector (D4) for passing the charged particle beam returned by the three deflectors on the optical axis, and at the time of calibration, the first to fourth deflectors (D1 to While driving one of the D4) at a set value, a drive current ( _ID ) is supplied to the optical axis adjusting alignment coil arranged on the upstream side of the charged particle beam with respect to the first deflector. , The driving current with which the aperture passing current detection value (I _EB ) is maximized is obtained, and similarly for the deflectors other than the one, the driving current with which the aperture passing current detection value is maximized is obtained, Based on the set drive amount and the obtained drive current, the first to
Determining the deflection characteristics of each of the four deflectors, the charged particle beam passes through the selected through hole pattern on the stencil mask perpendicular to the stencil mask, and then is swung back to pass on the optical axis. The first to fourth deflector drive amounts for achieving the above are obtained based on the deflection characteristics, and the drive amounts (V) of the first to fourth deflectors are changed in the vicinity of the obtained drive amount, The deflector such that the positional deviation (x) of the irradiation point on the sample from the origin detected when the charged particle beam is passed through the passage hole pattern is minimized and the detected current is maximized. 7. The charged particle beam deflection control method for a stencil mask according to claim 1, wherein the driving amount is obtained. 8. The mask incident side deflector (ID) deflects a charged particle beam (EB) passing on the optical axis (C) to the selected passage hole pattern side on the stencil mask (12). First deflector (D1) and a second deflector (D) for making the charged particle beam oscillated by the first deflector parallel to the optical axis and passing it perpendicularly to the passage hole pattern.
2), the mask emission side deflector (OD) includes a third deflector (D3) for returning the charged particle beam that has passed through the passage hole pattern to the optical axis side, and the third deflector (D3). The third deflector has a fourth deflector (D4) for passing the charged particle beam reflected by the deflector on the optical axis, and during calibration, the charged particle beam is on the stencil mask. The first deflector and the second deflector are driven so as to pass through the selected passage hole pattern, and the drive amount is fixed (5
0), driving of the third deflector when the charged particle beam that has passed through the through-hole pattern is swung back and passes substantially on the optical axis, passes through the aperture, and the detection value of the aperture passing current becomes maximum. Two or more sets of the amount, the driving amount of the fourth deflector, and the irradiation point position of the charged particle beam on the sample (51 to
56), based on the determined two or more sets of the third deflector drive amount, the fourth deflector drive amount, and the irradiation point position, the third deflector drive amount and the fourth deflector drive amount.
A relational expression between the deflector drive amount and the irradiation point position is approximately determined, and from the relational expression, the third deflector drive amount and the fourth deflector drive in which the irradiation point position is the origin The charged particle beam deflection control method for a stencil mask according to any one of claims 1 to 3 and 7, characterized in that the amount (57) is obtained.