JP7357741B2 - Evaluation method and charged particle beam device - Google Patents

Description

The present invention relates to an evaluation method and a charged particle beam device.

2. Description of the Related Art An electron beam writing device is known as a charged particle beam device that uses a charged particle beam such as an electron beam. An electron beam drawing device is used, for example, to draw fine semiconductor integrated circuit patterns (LSI patterns, etc.). In the electron beam lithography apparatus, calibration of the control operation of the electron beam and inspection of the control operation are periodically performed.

For example, Patent Document 1 discloses an electron beam lithography apparatus that can detect an irradiation position of an electron beam on a sample in real time and detect abnormalities such as positional deviation of the electron beam.

Japanese Patent Application Publication No. 2006-339405

FIG. 43 is a diagram for explaining an example of a conventional abnormality detection method of control operation in an electron beam lithography apparatus. FIG. 44 is a graph showing the waveform of a detection signal obtained by detecting an electronic signal (secondary electrons or reflected electrons) generated by scanning the mark M with the electron beam EB. Note that in the graph shown in FIG. 44, the horizontal axis represents time t, and the vertical axis represents the intensity I of the detection signal.

As shown in FIG. 43, the electron beam EB is moved in predetermined steps to scan the mark M with the electron beam EB. As a result, electron signals (secondary electrons and reflected electrons) are emitted from the region irradiated with the electron beam EB. By detecting this electronic signal with a detector (not shown) and observing the detection signal, the waveform of the detection signal shown in FIG. 44 is obtained. From the waveform of this detection signal, it can be confirmed whether there is any abnormality in the control operation of the beam control system. That is, the control operation of the beam control system can be evaluated from the waveform of the detection signal.

In the conventional control operation evaluation method described above, if a clear abnormality occurs in the control operation, such as when an element making up the beam control system breaks down, the waveform of the detection signal changes significantly, making it difficult to detect the abnormality. can. However, with the conventional control operation abnormality detection method, for example, if a slight abnormality occurs in the control operation due to performance deterioration of the elements constituting the beam control system, the abnormality may not be detected.

45 and 46 are diagrams showing an example of the waveform (voltage output) of an output signal of a control circuit that controls an electrostatic deflector for deflecting an electron beam. Note that FIG. 45 shows a waveform in a normal state, and FIG. 46 shows a waveform in an abnormal state.

If the characteristics of elements such as transistors forming the control circuit (including the output amplifier, etc.) deteriorate over time, ringing may occur in the output signal of the control circuit, as shown in FIG. 46. A slight distortion in the waveform of the output signal due to ringing or the like cannot be detected by the conventional abnormality detection method described above.

If an abnormality occurs in the drawing result due to a slight distortion in the waveform of the output signal, the quality of the product such as a photomask may deteriorate, resulting in a decrease in the reliability of the device. It becomes one.

The present invention has been made in view of the above-mentioned problems, and one of the objects of some aspects of the present invention is to provide an evaluation method that can accurately evaluate control operations. There is a particular thing. Further, one of the objects of some aspects of the present invention is to provide a charged particle beam device that can accurately evaluate control operations.

One aspect of the evaluation method according to the present invention is
A charged particle source, a shaping deflector and an aperture that shape a charged particle beam emitted from the charged particle source, and a detection device that detects a charged particle beam or a signal generated when a measurement target is irradiated with the charged particle beam. A method for evaluating the control operation of the shaping deflector control device in a charged particle beam device comprising: a shaping deflector controller;
When the shaping deflector control device performs a control operation to control the shaping deflector so that the charged particle beam changes from a first cross-sectional area to a second cross-sectional area different in size from the first cross-sectional area. a step of observing a transient response and evaluating a control operation of the shaping deflector control device;
The transient response is determined by the charged particle beam until a predetermined time elapses after the charged particle beam changes from the first cross-sectional area to the second cross-sectional area, or the detected signal obtained by detecting the signal with the detector. Observation is made by detecting an abnormality in the waveform of the output signal of the shaping deflector control device from the waveform showing the time change .

In such an evaluation method, slight distortion such as ringing occurring in the waveform of the output signal of the shaping deflector control device can be observed from the waveform of the detection signal. Therefore, according to such an evaluation method, an abnormality in the control operation of the shaping deflector control device can be detected with high accuracy.

One aspect of the charged particle beam device according to the present invention is
a charged particle source;
a shaping deflector and an aperture for shaping the charged particle beam emitted from the charged particle source;
a detector that detects a charged particle beam or a signal generated when a measurement target is irradiated with the charged particle beam;
a shaping deflector control device that controls the shaping deflector;
a detection signal acquisition unit that acquires a detection signal obtained by detecting the charged particle beam or the signal with the detector;
When the shaping deflector control device performs a control operation to control the shaping deflector so that the charged particle beam changes from a first cross-sectional area to a second cross-sectional area different in size from the first cross-sectional area. an evaluation unit that observes a transient response during the control operation based on the detection signal and evaluates the control operation of the shaping deflector control device;
including ;
The evaluation unit calculates an output signal of the shaping deflector control device from a waveform indicating a change in the detection signal over time from when the charged particle beam changes from the first cross-sectional area to the second cross-sectional area and a predetermined time elapses. The transient response during the control operation is observed by detecting an abnormality in the waveform .

In such a charged particle beam device, slight distortion such as ringing that occurs in the waveform of the output signal of the shaping deflector control device can be observed from the waveform of the detection signal. Therefore, according to such a charged particle beam device, an abnormality in the control operation of the shaping deflector control device can be detected with high accuracy.

FIG. 1 is a diagram showing the configuration of an electron beam lithography apparatus according to a first embodiment. FIG. 3 is a diagram showing the configuration of a deflection signal control circuit. FIG. 3 is a diagram showing the configuration of a signal detection control circuit. 1 is a flowchart illustrating an example of an abnormality detection method according to the first embodiment. FIG. 3 is a diagram for explaining an abnormality detection method according to the first embodiment. FIG. 6 is a diagram showing the movement of an electron beam when the waveform of the output signal of the deflection signal control circuit is distorted. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. 5 is a flowchart showing a modification of the abnormality detection method according to the first embodiment. 7 is a flowchart illustrating an example of an abnormality detection method according to the second embodiment. FIG. 7 is a diagram for explaining an abnormality detection method according to a second embodiment. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. 7 is a flowchart illustrating an example of an abnormality detection method according to a third embodiment. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. FIG. 7 is a diagram for explaining an example of an abnormality detection method according to a fourth embodiment. FIG. 7 is a diagram for explaining an example of an abnormality detection method according to a fifth embodiment. FIG. 7 is a diagram showing the configuration of an electron beam lithography apparatus according to a sixth embodiment. 10 is a flowchart illustrating an example of an abnormality detection method according to a sixth embodiment. FIG. 7 is a diagram for explaining an abnormality detection method according to a sixth embodiment. FIG. 7 is a diagram for explaining an abnormality detection method according to a sixth embodiment. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. 10 is a flowchart illustrating an example of an abnormality detection method according to a seventh embodiment. FIG. 7 is a diagram for explaining an abnormality detection method according to a seventh embodiment. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. FIG. 7 is a diagram showing the configuration of an electron beam lithography apparatus according to an eighth embodiment. A diagram for explaining how astigmatism is corrected. A diagram for explaining how astigmatism is corrected. 12 is a flowchart illustrating an example of an abnormality detection method according to an eighth embodiment. FIG. 7 is a diagram for explaining an abnormality detection method according to an eighth embodiment. FIG. 7 is a diagram for explaining a modification of the abnormality detection method according to the eighth embodiment. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. A graph showing the waveform of a detection signal. FIG. 3 is a diagram for explaining an example of an abnormality detection method of an astigmatism correction circuit using a measurement object. FIG. 3 is a diagram for explaining how an electron beam is detected by a beam current detector and a detection signal is observed. FIG. 2 is a diagram for explaining an example of a conventional control operation abnormality detection method. A graph showing the waveform of a detection signal. FIG. 3 is a diagram showing an example of a waveform of an output signal of a control circuit. FIG. 3 is a diagram showing an example of a waveform of an output signal of a control circuit.

Hereinafter, preferred embodiments of the present invention will be described in detail using the drawings. Note that the embodiments described below do not unduly limit the content of the present invention described in the claims. Furthermore, not all of the configurations described below are essential components of the present invention.

Further, in the following, an electron beam lithography device will be explained as an example of the charged particle beam device according to the present invention, but the charged particle beam device according to the present invention can handle charged particle beams other than electron beams (such as ion beams). It may also be a device that irradiates. The charged particle beam device according to the present invention may be, for example, an electron microscope, a focused ion beam device, or the like.

1. First embodiment 1.1. Electron Beam Drawing Apparatus First, an electron beam drawing apparatus according to a first embodiment will be described with reference to the drawings. FIG. 1 is a diagram showing the configuration of an electron beam lithography apparatus 100 according to the first embodiment.

As shown in FIG. 1, the electron beam drawing apparatus 100 includes an electron source (an example of a charged particle source) 10, a blanking deflector 12, an electron lens 14, a slit 16 (aperture), and a beam deflector 18. , an electron lens 20 (objective lens), a stage 22, an electron detector 24, a beam current detector 26, a high voltage power supply 28, a blanking control circuit 30, a lens control circuit 32, and a deflection signal control circuit 34. (an example of a deflector control device), a signal detection control circuit 36 (an example of a detection signal acquisition section), a data control section 38, and a control section 40.

The electron source 10 is, for example, an electron gun that emits an electron beam.

The blanking deflector 12 deflects the electron beam emitted from the electron source 10 and blanks the electron beam (that is, blocks the electron beam). This makes it possible to control on/off of the electron beam.

Electron lens 14 and electron lens 20 converge the electron beam. The slit 16 (aperture) cuts off unnecessary electron beams and controls the amount of current of the electron beam irradiated onto the sample S. Note that the electron beam drawing apparatus 100 may include lenses and slits other than the electron lens 14, the slit 16, and the electron lens 20.

The beam deflector 18 deflects the electron beam two-dimensionally. By deflecting the electron beam with the beam deflector 18, the electron beam can be moved or stopped at a desired position.

A sample S is placed on the stage 22 . The sample S is, for example, a semiconductor substrate, a mask blank, or the like. The stage 22 includes a moving mechanism that moves the sample S to a desired position.

The electron detector 24 detects an electronic signal (secondary electrons or backscattered electrons) generated when an electron beam is irradiated onto a measurement object (for example, a sample S, a mark 2 used for abnormality detection described later, etc.). It is a detector that The electron beam drawing apparatus 100 may include a secondary electron detector or a backscattered electron detector as the electron detector 24. Further, the electron beam drawing apparatus 100 may include two electron detectors 24 (a secondary electron detector and a backscattered electron detector).

A beam current detector 26 is provided on the stage 22. The beam current detector 26 is used, for example, together with a knife edge (not shown), to measure the current, size, position, blur of the electron beam, etc. of the electron beam used for writing, prior to writing on the sample S.

The high voltage power supply 28 is a power supply that generates a voltage for accelerating the electron beam emitted from the electron source 10.

The blanking control circuit 30 receives the output from the data control section 38 and controls the blanking deflector 12. The blanking deflector 12 operates in response to the output of the blanking control circuit 30.

The lens control circuit 32 receives the output of the data control section 38 and controls the electronic lens 14 and the electronic lens 20. The electronic lens 14 and the electronic lens 20 operate in response to the output of the lens control circuit 32.

The deflection signal control circuit 34 receives the output of the data control section 38 and controls the beam deflector 18. The beam deflector 18 operates upon receiving the output of the deflection signal control circuit 34.

The signal detection control circuit 36 is used to acquire (observe) a detection signal obtained by the electronic detector 24 detecting an electronic signal. The signal detection control circuit 36 collects and processes the output (detection signal) of the electronic detector 24. Further, the signal detection control circuit 36 is also used to acquire (observe) a detection signal obtained by the beam current detector 26 detecting the beam current. Details of the signal detection control circuit 36 will be described later.

The data control section 38 receives drawing data from the control section 40 and controls the blanking control circuit 30, the lens control circuit 32, and the deflection signal control circuit 34. Further, the data control section 38 performs a process of sending the detection signals collected and processed by the signal detection control circuit 36 to the control section 40 . The functions of the data control unit 38 can be realized by, for example, a dedicated circuit.

The control unit 40 is a computer that controls the overall operation of the electron beam lithography apparatus 100. The control unit 40 also functions as an abnormality detection unit (an evaluation unit that evaluates the control operation of the deflection signal control circuit 34) that detects an abnormality in the control operation of the deflection signal control circuit 34, as will be described later.

The function of the control unit 40 is, for example, when a processor (such as a CPU (Central Processing Unit)) executes a program stored in a storage device (not shown) such as a ROM (Read Only Memory) or a RAM (Random Access Memory). This can be achieved by doing this.

Next, the operation when the electron beam drawing apparatus 100 draws a pattern on the sample S will be described.

In the electron beam drawing apparatus 100, the electron beam emitted from the electron source 10 is focused onto the sample S by the electron lens 14 and the electron lens 20. Here, when the drawing data (pattern data) is stored in the storage device of the control unit 40, the stored drawing data is processed by the data control unit 38, and is then processed by the blanking control circuit 30, the lens control circuit 32, and the deflection control circuit 32. The signal is sent to the signal control circuit 34. The electron beam is turned on and off by a blanking deflector 12, and is deflected to a predetermined position on the sample S by a beam deflector 18. By combining the movement of the electron beam and the movement of the stage 22, a pattern based on the drawing data can be written. The stage 22 is controlled by a control unit 40, for example.

Note that the electron beam lithography apparatus 100 may be a variable shaped beam type electron beam lithography apparatus. That is, the electron beam drawing apparatus 100 may have a plurality of slits (not shown) that make the cross-sectional shape of the electron beam rectangular and make the size variable. In such an electron beam writing apparatus 100, a drawing pattern can be divided into rectangular shapes, and the pattern can be drawn using a rectangular electron beam whose size is adjusted according to the divided pattern.

1.2. Abnormality Detection Method Next, an abnormality detection method according to the first embodiment will be explained. Here, a case will be described in which an abnormality in a control operation when deflecting an electron beam is detected in the electron beam drawing apparatus 100.

The abnormality detection method according to the first embodiment observes a transient response when the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the first position to the second position. However, it includes a step of evaluating the control operation of the deflection signal control circuit 34, and the transient response is observed by detecting an electronic signal with the electronic detector 24 and obtaining a detection signal.

In the abnormality detection method according to the first embodiment, the output (step response) when a predetermined input (a control signal for moving the electron beam from the first position to the second position, step input) is given to the deflection signal control circuit 34 is observed to detect an abnormality in the deflection signal control circuit 34.

FIG. 2 is a diagram showing the configuration of the deflection signal control circuit 34. As shown in FIG.

As shown in FIG. 2, the deflection signal control circuit 34 includes a D/A converter 341, an output amplifier 342, a monitor amplifier 343, and an A/D converter 344. The output (control signal) of the data control section 38 is D/A converted (digital-to-analog conversion) by a D/A converter 341 and output from an output amplifier 342. The output (output signal) of the deflection signal control circuit 34 (output amplifier 342) can be observed by the monitor amplifier 343 and the A/D converter 344.

For example, if the performance of elements such as transistors constituting the output amplifier 342 deteriorates, distortion such as ringing may occur in the output signal of the deflection signal control circuit 34 (see FIG. 46). Such an abnormality in the output due to performance deterioration of the output amplifier 342 has small fluctuations and is fast. Therefore, it is difficult to confirm by observing the output from the monitor amplifier 343 and the A/D converter 344. It may be possible to add a circuit that can observe such high-speed fluctuations in output, but this may cause problems such as the influence of response load on control operations and the increase in circuit scale, which increases the failure rate and reduces reliability. be.

Therefore, in the abnormality detection method according to the first embodiment, a transient response occurs when the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the first position to the second position. By observing this, an abnormality in the control operation (output) of the deflection signal control circuit 34 is detected. The transient response is performed by acquiring a detection signal with the signal detection control circuit 36.

FIG. 3 is a diagram showing the configuration of the signal detection control circuit 36.

As shown in FIG. 3, the signal detection control circuit 36 includes a first stage amplifier 361, a signal switching section 362, an amplification amplifier 363, a gain switching section 364, an A/D conversion section 365, and a level/gain control section 366. and a timing adjustment section 367.

In the signal detection control circuit 36, a signal switching unit 362 selects either the detection signal from the electronic detector 24 or the detection signal from the beam current detector 26. The selected detection signal is amplified by an amplification amplifier 363 whose signal gain is adjusted by a gain switching section 364, and A/D converted (analog-digital conversion) by an A/D conversion section 365. Thereby, the detection signal can be acquired (observed). The time and timing for acquiring (observing) the detection signal is controlled by the timing adjustment section 367. Further, signal gain control is performed by a level/gain control section 366.

FIG. 4 is a flowchart illustrating an example of the abnormality detection method according to the first embodiment. FIG. 5 is a diagram for explaining the abnormality detection method according to the first embodiment.

(1) Setting abnormality detection conditions (S100)
First, conditions for detecting an abnormality are set. Specifically, the alignment of the mark 2, the setting of the starting position A (an example of the first position) and the resting position B (an example of the second position) when moving the electron beam EB, the time for observing the detection signal, and the Perform timing settings, etc. The set conditions are stored in the storage device of the control unit 40.

First, mark 2 shown in FIG. 5 will be explained. Mark 2 becomes a measurement target for detecting an abnormality. Mark 2 is placed on stage 22. The mark 2 is provided on the substrate 3 and placed on the stage 22 together with the substrate 3, as shown in FIG. Note that the mark 2 may be provided directly on the stage 22 (or sample holder). Mark 2 is linear in plan view. For example, a plurality of linear marks 2 may be provided, and the plurality of marks 2 arranged in the X direction and the plurality of marks 2 arranged in the Y direction may be arranged so as to be orthogonal to each other.

The mark 2 is made of heavy metal, for example. The substrate 3 is made of, for example, a semiconductor substrate. The cross-sectional shape of the mark 2 is trapezoidal in the illustrated example, but the shape is not particularly limited. By placing the mark 2 on the substrate 3, an area outside the mark 2 (an area made up of the top surface of the substrate 3) 2a (an example of the first area), an area made up of the top surface of the mark 2 2b (an example of a second region), and a region 2c (an example of a third region) constituted by the edge portion (slanted surface) of the mark 2. Region 2c is located between region 2a and region 2b. Region 2c and region 2a are in contact with each other, and region 2c and region 2b are in contact with each other. As described above, in the first embodiment, the measurement target is composed of the mark 2 and the substrate 3, and has the region 2a, the region 2b, and the region 2c.

Since the mark 2 is made of heavy metal, when irradiated with the electron beam EB under the same irradiation conditions, more electron signals are emitted in the region 2b and the region 2c than in the region 2a outside the mark 2. Therefore, the intensity of the detection signal is greater in the region 2b and the region 2c than in the region 2a. Moreover, since the directions in which the surfaces of the regions 2b and 2c face are different, the directions in which reflected electrons are emitted are different. Therefore, for example, when detecting reflected electrons as an electron signal, even if the electron beam EB is irradiated under the same irradiation conditions, a difference occurs in the intensity of the detection signal between the region 2b and the region 2c. Here, it is assumed that when the electron beam EB is irradiated under the same irradiation conditions, the intensity of the detection signal is greater in the region 2b than in the region 2c.

Therefore, when the electron beam EB is irradiated under the same irradiation conditions, the intensity of the detection signal observed in area 2a is Ia, the intensity of the detection signal observed in area 2b is Ib, and the intensity of the detection signal observed in area 2c is When the signal strength is Ic,
Ia<Ic<Ib
satisfies the relationship.

In addition, in the above, by making the material of the region 2a different from that of the regions 2b and 2c, and by making the surface shape of the region 2b and the surface shape of the region 2c different, Ia<Ic<Ib is satisfied. Although the case where the relationship is satisfied has been described, the surface shape and material of the object to be measured are not particularly limited as long as the above relationship is satisfied. For example, the above relationship may be satisfied by making the materials of the region 2a, the material of the region 2b, and the material of the region 2c different from each other, or the surface shape of the region 2a, the surface shape of the region 2b, and the material of the region 2c may be made different. The above relationship may be satisfied by making the surface shapes different from each other. Further, the above relationship may be satisfied by a combination of the surface shape and material of each region.

Next, the setting of the starting position A and the resting position B when moving the electron beam EB will be explained.

The starting position A is set within the area 2a, and the rest position B is set within the area 2c. Furthermore, the electron beam EB is set to remain stationary at a stationary position B for a predetermined period of time. Specifically, a control operation is performed in which the deflection signal control circuit 34 controls the beam deflector 18 so that the electron beam EB moves from the starting position A to the stationary position B and remains stationary at the stationary position B for a predetermined period of time. It is set as follows. This setting is performed, for example, by storing control data in the storage device of the control unit 40. The time (predetermined time) during which the electron beam EB remains stationary at the stationary position B is appropriately set, for example, depending on the type of abnormality to be detected.

By setting the rest position B within the region 2c, the effect of slight distortion (ringing, etc.) occurring in the waveform of the output signal of the deflection signal control circuit 34 appears on the waveform of the detection signal.

FIG. 6 is a diagram showing the movement of the electron beam EB when the waveform of the output signal of the deflection signal control circuit 34 is distorted.

As shown in FIG. 6, when the output signal of the deflection signal control circuit 34 has a slight distortion due to ringing (see FIG. 46), the operation of the beam deflector 18 that receives the output signal causes the electron beam EB to It does not remain at rest position B, but moves (vibrates) slightly. Due to this movement (vibration) of the electron beam EB, the irradiation area of the electron beam EB becomes an area including the area 2c and the area 2a, or an area including the area 2c and the area 2b. As a result, the intensity of the detection signal changes, so that the effect of slight distortion occurring in the waveform of the output signal of the deflection signal control circuit 34 appears on the waveform of the detection signal.

The starting position A is not particularly limited as long as it is within the area 2a that is the area outside the mark 2. Therefore, by setting the starting position A according to the deflection distance for which the operation is to be checked and the amplitude value of the waveform of the output signal, it is possible to detect abnormalities under desired deflection conditions.

The stationary position B is within the region 2c, which is the edge portion of the mark 2, so if the region 2c and the position where you want to check the deflection of the electron beam deviate from each other, move the stage or use another beam deflector ( (not shown) to adjust the position.

(2) Deflection of electron beam to starting position A (S102)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves to the starting position A. This deflects the electron beam to the starting position A. The deflection signal control circuit 34 receives the output of the data control section 38 based on control data and performs a control operation. The same applies to the control operations (S106, S108) of the deflection signal control circuit 34, which will be described later.

(3) Observation start (S104)
Next, observation (acquisition) of the detection signal is started. The detection signal is obtained using the signal detection control circuit 36, as described above.

(4) Deflection of electron beam to stationary position B (S106)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the starting position A to the resting position B. The movement of the electron beam from the starting position A to the resting position B is performed with the electron beam on.

(5) Stationary electron beam at stationary position B (S108)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam remains at rest position B for a predetermined period of time.

(6) End of observation (S110)
After performing a control operation to control the beam deflector 18 so that the electron beam remains stationary at the stationary position B for a predetermined period of time, the acquisition (observation) of the detection signal ends. Through the above processing, detection signals can be observed (continuous observation) from before the electron beam moves from the start position A to the stationary position B until it stops at the stationary position B and a predetermined period of time has elapsed.

The detection signal acquired using the signal detection control circuit 36 is processed by the control section 40. As a result, a waveform (waveform of the detection signal) indicating a change in the detection signal over time from before the electron beam moves from the starting position A to the stationary position B until a predetermined time elapses after the electron beam stops at the stationary position B is generated. . The waveform of this detection signal is displayed on, for example, a display section (not shown) of the control section 40 and stored in a storage device.

(7) Detection of abnormality (S112)
Next, an abnormality in the control operation of the deflection signal control circuit 34 is detected from the waveform of the detection signal.

7 to 9 are graphs showing the waveforms of detection signals from before the electron beam moves from the starting position A to the stationary position B until it stops at the stationary position B and a predetermined period of time has elapsed. 7 and 8 are graphs showing the waveform of the detection signal observed when the waveform of the output signal of the deflection signal control circuit 34 is abnormal. FIG. 9 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the deflection signal control circuit 34 is normal.

Note that in the graphs shown in FIGS. 7 to 9, the horizontal axis indicates time t, and the vertical axis indicates the intensity I of the detection signal. Furthermore, in FIGS. 7 to 9, the intensity Ia is the intensity of the detection signal observed when the region 2a is irradiated with the electron beam. Moreover, the intensity Ib is the intensity of the detection signal observed when the region 2b is irradiated with the electron beam. Moreover, the intensity Ic is the intensity of the detection signal observed when the region 2c is irradiated with the electron beam.

As shown in FIGS. 7 and 8, when there is an abnormality in the waveform of the output signal (input waveform) of the deflection signal control circuit 34, the waveform of the detection signal (response waveform) changes. Therefore, an abnormality in the control operation (output signal) of the deflection signal control circuit 34 can be detected by comparing the waveform of the detection signal observed in the above-mentioned measurement with the waveform of the detection signal during normal operation shown in FIG. Can be done.

Specifically, the waveform of the detection signal shown in FIG. 7 is observed when ringing as shown in FIG. 46 occurs in the waveform of the output signal of the deflection signal control circuit 34. For example, if the interval at which the detection signal is observed is smaller than the ringing cycle, the waveform of the detection signal similar to the waveform of the output signal shown in FIG. 46 is observed. Furthermore, if the interval at which the detection signal is observed is longer than the ringing cycle, the waveform due to the ringing of the output signal is integrated and appears in the waveform of the detection signal. Therefore, in the waveform of the detection signal shown in FIG. 7, a peak is observed at the rising edge. As described above, it can be seen from the waveform of the detection signal shown in FIG. 7 that ringing occurs in the output signal of the deflection signal control circuit 34.

The waveform of the detection signal shown in FIG. 8 is observed when there is a delay in the response time of the deflection signal control circuit 34. The waveform of the detection signal shown in FIG. 8 has a delay in the time it takes for the intensity of the detection signal to reach the intensity Ic compared to the waveform of the detection signal during normal operation shown in FIG. 9 due to a delay in response time. As described above, it can be seen from the waveform of the detection signal shown in FIG. 8 that there is a delay in response time.

The control unit 40 observes the transient response during the control operation based on the detection signal when performing the control operation to move the electron beam from the starting position A to the stationary position B, and adjusts the control operation of the deflection signal control circuit 34. detect abnormalities. Specifically, the control unit 40 compares the waveform of the acquired detection signal with the waveform of a normal detection signal to detect an abnormality in the control operation of the deflection signal control circuit 34. Note that the abnormality may be detected by the user comparing the waveform of the detection signal with the waveform of the detection signal during normal operation.

The abnormality detection method according to the first embodiment has, for example, the following characteristics.

The abnormality detection method according to the first embodiment observes a transient response when the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the starting position A to the stationary position B. However, it includes a step of evaluating the control operation of the deflection signal control circuit 34, and the transient response is observed by detecting an electronic signal with the electronic detector 24 and obtaining a detection signal. Therefore, according to the abnormality detection method according to the first embodiment, a slight distortion in the waveform of the output signal of the deflection signal control circuit 34 can be observed from the waveform of the detection signal. Therefore, according to the abnormality detection method according to the first embodiment, abnormalities in the control operation of the deflection signal control circuit 34 can be detected with high accuracy. Furthermore, according to the abnormality detection method according to the first embodiment, abnormality detection can be performed with a simple configuration.

In the abnormality detection method according to the first embodiment, in the process of evaluating the control operation, detection is performed from the state where the electron beam is located at the starting position A until the electron beam moves to the stationary position B and a predetermined period of time has elapsed. The signal is observed and the control operation is evaluated based on the time change of the detected signal. Therefore, according to the abnormality detection method according to the first embodiment, abnormality in control operation can be detected with high accuracy.

In the abnormality detection method according to the first embodiment, the measurement target including the mark 2 and the substrate 3 has a region 2a, a region 2b, and a region 2c located between the region 2a and the region 2b. have. Furthermore, when the electron beam is irradiated under the same irradiation conditions, the intensity of the detection signal observed in region 2a is Ia, the intensity of the detection signal observed in region 2b is Ib, and the detection signal observed in region 2c. When the intensity of is Ic, there is a relationship of Ia<Ic<Ib. Further, the rest position B is the area 2c. Therefore, in the first embodiment, slight distortion such as ringing that occurs in the waveform of the output signal of the deflection signal control circuit 34 can be observed as a change in the waveform of the detection signal.

The electron beam drawing apparatus 100 according to the first embodiment includes an electron source 10, a beam deflector 18 that deflects the electron beam emitted from the electron source 10, and an electron beam generated when the measurement target is irradiated with the electron beam. An electronic detector 24 that detects an electronic signal, a deflection signal control circuit 34 that controls the beam deflector 18, and a signal detection control circuit 36 that acquires a detection signal obtained by detecting an electronic signal with the electronic detector 24. Based on the detection signal when the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the starting position A to the stationary position B, the transient response during the control operation is observed. It also includes a control section 40 (an example of an evaluation section) that evaluates the control operation of the deflection signal control circuit 34.

Therefore, in the electron beam lithography apparatus 100, abnormalities in the control operation of the deflection signal control circuit 34 can be detected with high accuracy. Further, in the electron beam drawing apparatus 100, by setting detection conditions (step S100), the processes of steps S102 to S112 can be performed automatically. Therefore, in the electron beam writing apparatus 100, abnormalities in the control operation of the deflection signal control circuit 34 can be easily detected.

Furthermore, in the electron beam lithography apparatus 100, an abnormality in the control operation of the deflection signal control circuit 34 can be easily detected, so that abnormality detection can be easily and periodically performed. Therefore, it is possible to maintain the performance of the beam control operation.

Furthermore, in the electron beam writing apparatus 100, by evaluating the control operation of the deflection signal control circuit 34 before pattern writing, it is possible to maintain the quality of the electron beam control operation and maintain high writing accuracy.

In addition, in the embodiment described above, a case has been described in which an abnormality in the control operation of the deflection signal control circuit 34 is detected from the waveform of the detection signal observed by the processing of steps S100 to S110 shown in FIG. It is also possible to evaluate the beam control system that controls the electron beam from the waveform of the detection signal observed through the processing in steps S100 to S110. For example, it is possible to evaluate the settling time of the deflection signal control circuit 34, beam response delay, etc. from the waveform of the detection signal.

The settling time is the time from when the control signal is input to the deflection signal control circuit 34 until the output settles to a set value.

In the electron beam lithography apparatus 100, when a certain position is irradiated with an electron beam and then the next position is irradiated with the electron beam, the electron beam is blanked while the electron beam is being moved. The time during which the electron beam is blanked is set short when the distance traveled by the electron beam is small (the amount of deflection of the electron beam is small), and when the distance traveled by the electron beam is large (the amount of deflection of the electron beam is large) ) is set to long.

The time during which the electron beam is blanked is the settling time plus a predetermined waiting time. By shortening this waiting time, it becomes possible to draw in a short time, although the drawing performance decreases. In addition, by lengthening the waiting time, writing performance can be improved, but writing takes time (response delay of electron beam). From the waveform of the detection signal observed in the processing of steps S100 to S110, it is possible to measure the settling time depending on the deflection distance and the time during which the electron beam is blanked. Therefore, for example, it is possible to evaluate whether the waiting time is appropriate.

Even when the deflection direction of the deflector and the number of electrodes are different, the waiting time can be evaluated by changing the detection condition settings (step S100). For example, by moving the position of the mark 2 with respect to the deflection direction of the electron beam, it is possible to evaluate the waiting time according to an arbitrary starting point and deflection distance. Further, for example, it is possible to evaluate the influence of an abnormality from the waveform (gain intensity) of a detection signal obtained by scanning a mark 2 of a known width with a beam size calibrated in advance.

As described above, the abnormality detection method according to the first embodiment is not limited to detecting an abnormality in the control operation of the deflection signal control circuit 34, but is an evaluation method for evaluating the control operation of the deflection signal control circuit 34 in general. It can be used as

In addition, in the above abnormality detection method, by preparing the mark 2 according to the deflection polarity of the beam deflector 18 and the deflection direction of the electron beam, an abnormality in the control operation in any deflection polarity or in any deflection direction can be detected. can do. For example, when the deflection direction of the electron beam is in the Y direction, detection sensitivity can be improved by using the mark 2 formed linearly in the X direction. That is, by using the mark 2 formed linearly at an angle of 90 degrees or close to 90 degrees with respect to the deflection direction of the electron beam, detection sensitivity can be improved. This allows more accurate abnormality detection.

1.3. Modification Next, a modification of the abnormality detection method according to the first embodiment will be described. FIG. 10 is a flowchart showing a modification of the abnormality detection method according to the first embodiment. Below, points that are different from the example of the abnormality detection method according to the first embodiment described above will be explained, and descriptions of similar points will be omitted.

In this modification, the electron beam moves from the starting position A to the stationary position B, stops, and the process of observing the detection signal until a predetermined period of time has elapsed is repeatedly performed. That is, in this modification, as shown in FIG. 10, the processes from step S102 to step S110 are repeated a preset number of times. The number of repetitions is appropriately set, for example, depending on the required detection accuracy.

Specifically, after performing the process of terminating the observation of the detection signal (after step S110), the control unit 40 determines whether the processes from step S102 to step S110 have been repeated a preset number of times. (S111). If the control unit 40 determines that the process has not been repeated the set number of times (No in S111), the process returns to step S102 and processes from step S102 to step S110 are performed. When the control unit 40 determines that the process has been repeated the set number of times (Yes in S111), a process for detecting an abnormality is performed (S112).

As described above, in this modification, the electron beam moves from the starting position A to the stationary position B and remains stationary, and the process of observing the detection signal until a predetermined period of time has elapsed is repeated, so the signal detection control circuit 36 The effects of initial fluctuations and detection variations can be reduced. Therefore, detection accuracy can be improved.

2. Second embodiment 2.1. Electron Beam Writing Apparatus The configuration of the electron beam writing apparatus according to the second embodiment is the same as the configuration of the electron beam writing apparatus according to the first embodiment shown in FIG. 1, and illustration and description thereof will be omitted.

2.2. Abnormality Detection Method Next, an abnormality detection method according to the second embodiment will be explained. Below, points that are different from the example of the abnormality detection method according to the first embodiment described above will be explained, and descriptions of similar points will be omitted.

In the abnormality detection method according to the first embodiment described above, the detection signal is observed (continuously observed) until a predetermined time elapses after the electron beam moves from the starting position A to the stationary position B.

In contrast, in the abnormality detection method according to the second embodiment, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 multiple times so that the electron beam moves from the starting position A to the resting position B. , the timing of acquiring the detection signal is made different in multiple control operations.

FIG. 11 is a flowchart illustrating an example of the abnormality detection method according to the second embodiment. FIG. 12 is a diagram for explaining the abnormality detection method according to the second embodiment.

(1) Setting abnormality detection conditions (S200)
First, conditions for detecting an abnormality are set. In the second embodiment, the timing at which the detection signal is observed differs each time the control operation is repeated, that is, each time the process of observing (obtaining) the detection signal is repeated. Therefore, the timing at which the detection signal is observed is set for each number of repetitions. The timing of observing the detection signal is appropriately set, for example, depending on the type of abnormality to be detected.

For example, if the reference time is when the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the starting position A to the stationary position B, then the first detection signal is observed. The timing to do this is set at the reference time. The timing to observe the second detection signal is set 0.1 seconds after the reference time, the timing to observe the third detection signal is set 0.2 seconds after the reference time, and so on. The timing for observing the detection signal is set at (n-1)/10 seconds after the reference time.

Setting of other conditions is performed in the same way as the process of step S100 shown in FIG.

(2) Deflection of electron beam to starting position A (S202)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves to the starting position A. This process is performed in the same manner as step S102 shown in FIG.

(3) Deflection of electron beam to stationary position B (S204)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the starting position A to the resting position B. This process is performed in the same way as step S106 shown in FIG.

(4) Stationary electron beam at stationary position B (S206)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam remains at rest position B for a predetermined period of time. This process is performed in the same way as step S108 shown in FIG.

(5) Observation (S208)
Next, the deflection signal control circuit 34 observes the detection signal at a preset timing. The detection signal is observed (obtained) using the signal detection control circuit 36, as described above. The timing at which the detection signal is observed is controlled by the timing adjustment section 367 shown in FIG.

(6) Repeat (S210)
The control unit 40 determines whether the processes from step S202 to step S208 have been repeated a preset number of times.

(7) Change the observation timing (S212)
If the control unit 40 determines that the process has not been repeated the set number of times (No in S210), it changes the timing at which the detection signal is observed. For example, when the second detection signal is observed after the first detection signal is observed, the control unit 40 sets the timing at which the detection signal is observed to be 0.1 seconds after the reference time. Then, the signal detection control circuit 36 (timing adjustment section 367) is controlled.

The control unit 40 changes the timing of observing the detection signal each time it performs the process of observing (obtaining) the detection signal until the process of observing the detection signal (S202 to S208) is repeated the set number of times. (S212), the process of observing the detection signal is repeated.

(8) Detection of abnormality (S214)
If the control unit 40 determines that the process has been repeated the set number of times (Yes in S210), it performs a process to detect an abnormality.

13 and 14 show that the process of detecting an electronic signal and observing the detected signal is performed multiple times, and the timing of observing the detected signal is different in each process of observing the detected signal performed multiple times. 3 is a graph showing the waveform of a detected signal. FIG. 13 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the deflection signal control circuit 34 is abnormal. FIG. 14 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the deflection signal control circuit 34 is normal.

As shown in FIG. 13, when there is an abnormality in the waveform of the output signal of the deflection signal control circuit 34, the waveform of the detection signal changes. Therefore, by comparing the observed waveform of the detection signal with the waveform of the normal detection signal shown in FIG. 14, it is possible to detect an abnormality in the control operation (output signal) of the deflection signal control circuit 34.

Specifically, the waveform of the detection signal shown in FIG. 13 is observed when ringing as shown in FIG. 46 occurs in the waveform of the output signal of the deflection signal control circuit 34. When ringing occurs, if the interval at which the detection signal is observed is smaller than the ringing period, a waveform similar to the waveform of the output signal shown in FIG. 46 will be observed in the detection signal waveform. If the interval at which the detection signal is observed is longer than the ringing period, the waveform of the output signal due to ringing as shown in FIG. 13 is integrated.

In the waveform of the detection signal shown in FIG. 13, the duration of distortion of the waveform of the output signal due to ringing (ringing time T) is observed as a change in the intensity of the detection signal. In this manner, the duration of distortion (ringing time T) of the waveform of the output signal of the deflection signal control circuit 34 can be determined from the waveform of the detection signal shown in FIG.

According to the abnormality detection method according to the second embodiment, the same effects as those of the first embodiment described above can be achieved. Furthermore, according to the abnormality detection method according to the second embodiment, the control operation is performed multiple times, and the timing at which the detection signal is acquired is different in the multiple control operations. Time can be measured.

Note that by using the abnormality detection method according to the second embodiment, it is also possible to evaluate settling time, beam response delay, etc., similarly to the first embodiment.

2.3. Modification Next, a modification of the abnormality detection method according to the second embodiment will be described. In the second embodiment described above, the control operation is performed multiple times, and the timing of acquiring the detection signal is different in the multiple control operations. However, in the multiple control operations, the timing of emitting the electron beam is different. You can also let At this time, the signal detection control circuit 36 may detect the detection signal continuously. By varying the timing of irradiating the electron beam, it is possible to observe (obtain) the same waveform of the detection signal as in the case of varying the timing of observing the detection signal. Therefore, according to this modification, the same effects as the abnormality detection method according to the second embodiment described above can be achieved.

3. Third embodiment 3.1. Electron Beam Writing Apparatus The configuration of the electron beam writing apparatus according to the third embodiment is the same as the configuration of the electron beam writing apparatus according to the first embodiment shown in FIG. 1, and illustration and description thereof will be omitted.

3.2. Abnormality Detection Method Next, an abnormality detection method according to the third embodiment will be explained. Below, points that are different from the examples of the abnormality detection method according to the first embodiment and the abnormality detection method according to the second embodiment described above will be explained, and descriptions of similar points will be omitted.

In the abnormality detection method according to the second embodiment described above, the control operation is performed a plurality of times, and the timing of acquiring the detection signal is made different in the plurality of control operations.

On the other hand, in the abnormality detection method according to the third embodiment, the control operation is performed a plurality of times, and the timing at which the detection signal is observed is the same in the plurality of control operations.

FIG. 15 is a flowchart illustrating an example of an abnormality detection method according to the third embodiment. Here, an abnormality detection method according to a third embodiment will be described with reference to FIGS. 1 and 12. Below, points that are different from the example of the abnormality detection method according to the first embodiment described above will be explained, and descriptions of similar points will be omitted.

(1) Setting abnormality detection conditions (S300)
First, conditions for detecting an abnormality are set. In the third embodiment, the detection signal is observed at the same timing every time the process of observing the detection signal is repeated. Therefore, the timing for observing the detection signal is set. The timing of observing the detection signal is appropriately set, for example, depending on the type of abnormality to be detected. Setting of other conditions is performed in the same way as the process of step S100 shown in FIG.

(2) Deflection of electron beam to starting position A (S302)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves to the starting position A. This process is performed in the same manner as step S102 shown in FIG.

(3) Deflection of electron beam to stationary position B (S304)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the starting position A to the resting position B. This process is performed in the same way as step S106 shown in FIG.

(4) Stationary electron beam at stationary position B (S306)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam remains at rest position B for a predetermined period of time. This process is performed in the same way as step S108 shown in FIG.

(5) Observation (S308)
Next, the deflection signal control circuit 34 performs a control operation to control the beam deflector 18 so that the electron beam moves from the starting position A to the stationary position B, and the detection is performed at a preset timing. Observe (obtain) the signal.

(6) Repeat (S310)
The control unit 40 determines whether the processing from step S302 to step S308 has been repeated a preset number of times. If the control unit 40 determines that the process has not been repeated the set number of times (No in S310), the process returns to step S302 and processes from step S302 to step S310 are performed.

(7) Detection of abnormality (S312)
If the control unit 40 determines that the process has been repeated the set number of times (Yes in S310), it performs a process to detect an abnormality.

16 and 17 are graphs showing waveforms of detection signals observed at the same timing in multiple control operations. FIG. 16 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the deflection signal control circuit 34 is abnormal. FIG. 17 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the deflection signal control circuit 34 is normal. In the graphs shown in FIGS. 16 and 17, the horizontal axis indicates the number of repetitions n, and the vertical axis indicates the intensity I of the detection signal.

As shown in FIG. 16, when there is an abnormality in the waveform of the output signal of the deflection signal control circuit 34, the waveform of the detection signal changes. Therefore, by comparing the observed waveform of the detection signal with the waveform of the normal detection signal shown in FIG. 17, it is possible to detect an abnormality in the control operation (output signal) of the deflection signal control circuit 34.

Specifically, the waveform of the detection signal shown in FIG. 16 is observed when ringing as shown in FIG. 46 occurs in the waveform of the output signal of the deflection signal control circuit 34. In the waveform of the detection signal shown in FIG. 16, compared to the signal strength (signal level) of the detection signal during normal operation shown in FIG. 17, the signal strength is increased by the amount that ringing occurs in the output signal. Therefore, in the third embodiment, by comparing the signal strength (signal level) of the observed detection signal with the signal strength (signal level) of the detection signal during normal operation, abnormalities in the control operation of the deflection signal control circuit 34 are detected. can be detected.

Furthermore, in the third embodiment, by repeating the process of acquiring the detection signal, it is possible to reduce the influence of initial fluctuations in the signal detection control circuit 36 and detection variations. Therefore, detection accuracy can be improved.

According to the abnormality detection method according to the third embodiment, the same effects as those of the first embodiment described above can be achieved. Furthermore, according to the abnormality detection method according to the third embodiment, the control operation is performed a plurality of times, and the timing at which the detection signal is observed is the same in the plurality of control operations. An abnormality can be detected by comparing the signal strength of the detection signal. Therefore, a complicated signal processing circuit for detecting an abnormality is not required, and it is effective in simply detecting an abnormality in the control operation of the deflection signal control circuit 34.

Note that by using the abnormality detection method according to the third embodiment, it is also possible to evaluate settling time, beam response delay, etc., similarly to the first embodiment.

3.3. Modification Next, a modification of the abnormality detection method according to the third embodiment will be described. In the third embodiment described above, the control operation is performed multiple times, and the timing at which the detection signal is observed is the same in the multiple control operations, but the timing at which the electron beam is irradiated is the same in the multiple control operations. You can also do this. At this time, the signal detection control circuit 36 may detect the detection signal continuously. By making the timing of irradiating the electron beam the same, it is possible to observe the same waveform of the detection signal as when the timing of observing the detection signal is made the same. Therefore, according to this modification, the same effects as the abnormality detection method according to the third embodiment described above can be achieved.

4. Fourth embodiment 4.1. Electron Beam Writing Apparatus The configuration of the electron beam writing apparatus according to the fourth embodiment is the same as the configuration of the electron beam writing apparatus according to the first embodiment shown in FIG. 1, and illustration and description thereof will be omitted.

4.2. Abnormality Detection Method In the first to third embodiments described above, the rest position B was set in the area 2c. Therefore, in the embodiment described above, when a slight distortion such as ringing occurs in the output signal of the deflection signal control circuit 34, this slight distortion can be observed as a change in the waveform of the detection signal.

On the other hand, in the fourth embodiment, the measurement target has two regions in which the intensity of the detection signal observed when irradiated with the electron beam under the same irradiation conditions is different, and the electron beam is applied to the two regions. Control it so that it remains stationary at the boundary. That is, the rest position B is set at the boundary between the two areas.

FIG. 18 is a diagram for explaining an example of the abnormality detection method according to the fourth embodiment. In the following, points different from the examples of the abnormality detection methods according to the first to third embodiments described above will be explained, and explanations of similar points will be omitted.

As shown in FIG. 18, the measurement object 4 has a region 4a and a region 4b. The region 4a and the region 4b are made of materials that have different efficiency in generating electronic signals upon irradiation with the electron beam EB. Therefore, the intensity of the detection signal observed in the region 4a and the region 4b differs when the region 4a and the region 4b are irradiated with the electron beam under the same irradiation conditions.

In the fourth embodiment, the rest position B is set at the boundary between the region 4a and the region 4b. That is, the irradiation area of the electron beam when the electron beam is stopped at the stationary position B includes the boundary between the area 4a and the area 4b. As a result, the influence of slight distortion (ringing, etc.) that occurs in the waveform of the output signal of the deflection signal control circuit 34 appears on the waveform of the detection signal, similar to the case where the rest position B is set in the region 2c (see FIG. 5). .

Note that in the above, by making the materials of the region 4a and the material of the region 4b different, the intensity of the detection signal observed when the electron beam is irradiated under the same irradiation conditions is made different. By making the surface shape of the region 4b different from that of the region 4b, the intensity of the detection signal observed when the electron beam is irradiated under the same irradiation conditions may be varied.

The fourth embodiment can provide the same effects as the first to third embodiments described above.

5. Fifth embodiment 5.1. Electron Beam Writing Apparatus The configuration of the electron beam writing apparatus according to the fifth embodiment is the same as the configuration of the electron beam writing apparatus according to the first embodiment shown in FIG. 1, and illustration and description thereof will be omitted.

5.2. Abnormality Detection Method In the first to third embodiments described above, the electron detector 24 detects an electronic signal (secondary electrons or reflected electrons) generated by irradiating the measurement target (mark 2) with an electron beam. The detection signal was observed (obtained).

On the other hand, in the fifth embodiment, the electron beam is detected by the beam current detector 26 and a detection signal is observed (obtained).

FIG. 19 is a diagram for explaining an example of the abnormality detection method according to the fifth embodiment. In the following, points different from the examples of the abnormality detection methods according to the first to third embodiments described above will be explained, and explanations of similar points will be omitted.

As shown in FIG. 19, the deflection signal control circuit 34 controls the beam deflector 18 so that the electron beam EB moves from an arbitrary starting position A to the tip of the knife edge 27 (stationary position B) and comes to rest. When the operation is performed, the electron beam (beam current) that is incident on the beam current detector 26 (Faraday cup) without being obstructed by the knife edge 27 is detected by the beam current detector 26, and a detection signal is observed (obtained). You may. In this case, the tip of the knife edge 27 corresponds to the boundary between the region 4a and the region 4b shown in FIG. 18. That is, the tip of the knife edge 27 is at the rest position B. Therefore, the waveform of the detection signal observed in the fifth embodiment is also affected by slight distortion (ringing, etc.) occurring in the waveform of the output signal of the deflection signal control circuit 34, as in the other embodiments described above. .

Therefore, the fifth embodiment can provide the same effects as the first to third embodiments described above.

6. Sixth embodiment 6.1. Electron Beam Drawing Apparatus Next, an electron beam drawing apparatus according to a sixth embodiment will be described with reference to the drawings. FIG. 20 is a diagram showing the configuration of an electron beam lithography apparatus 200 according to the sixth embodiment. Hereinafter, in the electron beam lithography apparatus 200 according to the sixth embodiment, members having the same functions as the constituent members of the electron beam lithography apparatus 100 according to the first embodiment are denoted by the same reference numerals, and detailed explanations thereof will be given. Omitted.

As shown in FIG. 20, the electron beam drawing apparatus 200 includes a shaping deflector 202, a first aperture 204a, a second aperture 204b, and a shaping control circuit 230 (of a shaping deflector control device) that controls the shaping deflector 202. example).

The electron beam lithography apparatus 200 is a variable shaped beam type electron beam lithography apparatus. The electron beam writing apparatus 200 can, for example, divide a drawing pattern into rectangles and draw the pattern using a rectangular electron beam whose size is adjusted according to the divided pattern.

In the electron beam lithography apparatus 200, the shaping deflector 202, the first aperture 204a, and the second aperture 204b shape the electron beam to determine the shot shape (the cross-sectional shape of the electron beam irradiated onto the sample S) and the shot size (the sample S). The cross-sectional area of the electron beam irradiated onto S can be adjusted.

The shaping deflector 202 deflects the electron beam two-dimensionally. The opening shapes of the first aperture 204a and the second aperture 204b are, for example, rectangular. Note that the shapes of the openings of the first aperture 204a and the second aperture 204b are not particularly limited. For example, the shape of the opening of the first aperture 204a and the shape of the opening of the second aperture 204b may be different. By controlling the traveling direction of the electron beam using the shaping deflector 202, the irradiation area of the electron beam on the second aperture 204b can be controlled. Thereby, the electron beam can be shaped.

The shaping control circuit 230 receives the output of the data control section 38 and controls the shaping deflector 202. The shaping deflector 202 operates in response to the output of the shaping control circuit 230.

In the illustrated example, the electron beam is shaped by two apertures (the first aperture 204a and the second aperture 204b), but the number of apertures for shaping the electron beam is not particularly limited.

In the electron beam writing apparatus 200, the data control section 38 receives writing data from the control section 40 and controls the blanking control circuit 30, the lens control circuit 32, the deflection signal control circuit 34, and the shaping control circuit 230. The control unit 40 also functions as an abnormality detection unit (an evaluation unit that evaluates the control operation of the molding control circuit 230) that detects an abnormality in the control operation of the molding control circuit 230, as will be described later.

Next, the operation when the electron beam drawing apparatus 200 draws a pattern on the sample S will be described.

In the electron beam drawing apparatus 200, the electron beam emitted from the electron source 10 is focused onto the sample S by the electron lens 14 and the electron lens 20. Here, when the drawing data (pattern data) is stored in the storage device of the control unit 40, the stored drawing data is processed by the data control unit 38, and the blanking control circuit 30, the lens control circuit 32, and the deflection signal are processed. It is sent to the control circuit 34 and the molding control circuit 230. The electron beam is shaped by the shaping deflector 202, the first aperture 204a, and the second aperture 204b, turned on and off by the blanking deflector 12, and deflected to a predetermined position on the sample S by the beam deflector 18. By combining the movement of the electron beam and the movement of the stage 22, a pattern based on the drawing data can be written.

6.2. Abnormality Detection Method Next, an abnormality detection method according to the sixth embodiment will be described. Below, points that are different from the example of the abnormality detection method according to the first embodiment described above will be explained, and descriptions of similar points will be omitted.

In the abnormality detection method according to the first embodiment described above, an abnormality in the control operation of the deflection signal control circuit 34 is detected. On the other hand, in the abnormality detection method according to the sixth embodiment, an abnormality in the control operation of the molding control circuit 230 is detected.

In the abnormality detection method according to the sixth embodiment, the shaping control circuit 230 controls the shaping deflector 202 so that the electron beam changes from a first cross-sectional area to a second cross-sectional area that is different in size from the first cross-sectional area. It includes a step of observing a transient response when a control operation is performed and evaluating the control operation of the molding control circuit 230, and the transient response is detected by detecting an electronic signal with the electronic detector 24 and obtaining a detection signal. Observe.

The shaping control circuit 230 has, for example, the same configuration as the deflection signal control circuit 34 shown in FIG. 2. Therefore, in the shaping control circuit 230, similarly to the deflection signal control circuit 34, for example, if the performance of elements such as transistors forming the output amplifier deteriorates, distortion such as ringing may occur in the output signal.

Therefore, in the abnormality detection method according to the sixth embodiment, the shaping control circuit 230 controls the shaping deflector 202 so that the electron beam changes from the first cross-sectional area to the second cross-sectional area that is different in size from the first cross-sectional area. The transient response when the control operation to be controlled is performed is observed, and an abnormality in the control operation (output) of the molding control circuit 230 is detected.

FIG. 21 is a flowchart illustrating an example of an abnormality detection method according to the sixth embodiment. 22 and 23 are diagrams for explaining the abnormality detection method according to the sixth embodiment. Note that the directions in which the electron beam EB is viewed are different between FIGS. 22 and 23.

(1) Setting abnormality detection conditions (S300)
First, conditions for detecting an abnormality are set. Specifically, the shot shape (first shot shape S1) and shot cross-sectional area (first shot area A1) of the electron beam EB in the initial state are set, and the shot shape of the electron beam EB after change (second shot shape S2), setting of shot cross-sectional area (second shot area A2), setting of time and timing for observing the detection signal, etc. The set conditions are stored in the storage device of the control unit 40.

The measurement object 6 for detecting an abnormality is not particularly limited as long as it generates an electronic signal when irradiated with the electron beam EB. The measurement object 6 is, for example, a metal film formed on a semiconductor wafer.

Here, as shown in FIG. 23, in the initial state, the shape of the electron beam EB (first shot shape S1) is set such that the length in the X direction is shorter than the length in the Y direction. Further, the shape of the electron beam EB after the change (second shot shape S2) is set to a shape in which the length in the Y direction is the same as the initial state, and the length in the X direction is changed. As a result, the change in the detection signal can be increased with respect to the change in the X direction of the electron beam EB. Therefore, it is possible to accurately evaluate the shaping of the electron beam EB in the X direction in the shaping control circuit 230. Note that when evaluating shaping in the Y direction, the initial state is such that the length of the electron beam EB in the Y direction is shorter than the length in the X direction, and the length in the Y direction is determined by fixing the length in the X direction. All you have to do is change.

(2) Shaping of electron beam (S302)
Next, the shaping control circuit 230 performs a control operation to control the shaping deflector 202 so that the electron beam EB has the first shot shape S1 and the first shot area A1. As a result, the electron beam EB has the first shot shape S1 and the first shot area A1. The molding control circuit 230 receives the output of the data control section 38 based on the control data and performs a control operation. The same applies to the control operation of the molding control circuit 230, which will be described later.

(3) Observation start (S304)
Next, observation (acquisition) of the detection signal is started. The detection signal is obtained using the signal detection control circuit 36.

(4) Shaping of electron beam (S306)
Next, the shaping control circuit 230 performs a control operation to control the shaping deflector 202 so that the electron beam EB changes from the first shot shape S1 and first shot area A1 to the second shot shape S2 and second shot area A2. I do. As a result, the electron beam EB has a second shot shape S2 and a second shot area A2. The shaping control circuit 230 controls the shaping deflector 202 so that the electron beam EB is maintained in the second shot shape S2 and second shot area A2 for a predetermined period of time.

(5) End of observation (S308)
After performing a control operation to control the shaping deflector 202 so that the electron beam EB changes from the first shot shape S1 and first shot area A1 to the second shot shape S2 and second shot area A2, a detection signal is acquired. (observation) ends. Through the above processing, the detection signal is observed (continuous observation) until a predetermined time elapses after the electron beam changes from the first shot shape S1 and first shot area A1 to the second shot shape S2 and second shot area A2. be able to.

The detection signal acquired using the signal detection control circuit 36 is processed by the control section 40. As a result, a waveform (detection signal waveform) is generated. The waveform of this detection signal is displayed on, for example, a display unit (not shown) of the control unit 40 and stored in a storage device.

(6) Detection of abnormality (S310)
Next, an abnormality in the control operation of the molding control circuit 230 is detected from the waveform of the detection signal.

24 to 26 are graphs showing waveforms of detection signals until a predetermined time elapses after the electron beam changes from the first shot shape S1 and first shot area A1 to the second shot shape S2 and second shot area A2. It is. 24 and 25 are graphs showing the waveform of the detection signal observed when the waveform of the output signal of the shaping control circuit 230 is abnormal. FIG. 26 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the shaping control circuit 230 is normal.

Note that in the graphs shown in FIGS. 24 to 26, the horizontal axis indicates time t, and the vertical axis indicates the intensity I of the detection signal. Further, in FIGS. 24 to 26, the intensity I _A1 is the intensity of the detection signal observed when the electron beam is set to the first shot area A1. Further, the intensity I _A2 is the intensity of the detection signal observed when the electron beam is set to the second shot area A2.

As shown in FIGS. 24 and 25, when there is an abnormality in the waveform of the output signal of the molding control circuit 230, the waveform of the detection signal changes. Therefore, by comparing the waveform of the detection signal observed in the measurement described above with the waveform of the detection signal during normal operation shown in FIG. 26, it is possible to detect an abnormality in the control operation (output signal) of the molding control circuit 230. can.

When a slight distortion due to ringing occurs in the output signal of the shaping control circuit 230 (see FIG. 46), the operation of the shaping deflector 202 that receives the output signal causes the electron beam EB to change from the first shot area A1 to the first shot area A1. Slight increases and decreases in the cross-sectional area are repeated until the 2-shot area reaches A2. As the cross-sectional area of the electron beam EB is repeatedly increased and decreased, the intensity of the electron signal emitted from the measurement object 6 changes. As a result, the effect of slight distortion occurring in the waveform of the output signal of the shaping control circuit 230 appears on the waveform of the detection signal.

Specifically, the waveform of the detection signal shown in FIG. 24 is observed when ringing as shown in FIG. 46 occurs in the waveform of the output signal of the shaping control circuit 230. In the waveform of the detection signal shown in FIG. 24, a peak due to ringing of the output signal is observed at the rising edge. As described above, it can be seen from the waveform of the detection signal shown in FIG. 24 that ringing occurs in the output signal of the shaping control circuit 230.

The waveform of the detection signal shown in FIG. 25 is observed when there is a delay in the response time of the shaping control circuit 230. The waveform of the detection signal shown in FIG. 25 has a delay in the time it takes for the intensity of the detection signal to reach the intensity _IA2 compared to the waveform of the detection signal during normal operation shown in FIG. 26 due to a delay in response time. . As described above, it can be seen from the waveform of the detection signal shown in FIG. 25 that there is a delay in response time.

The control unit 40 determines the control operation at the time of the control operation based on the detection signal when the electron beam is changed from the first shot shape S1 and the first shot area A1 to the second shot shape S2 and the second shot area A2. The transient response of the molding control circuit 230 is observed to detect an abnormality in the control operation of the molding control circuit 230. Specifically, the control unit 40 compares the waveform of the acquired detection signal with the waveform of a normal detection signal to detect an abnormality in the control operation of the molding control circuit 230. Note that the abnormality may be detected by the user comparing the waveform of the detection signal with the waveform of the detection signal during normal operation.

In addition, although the case where the control operation to increase the shot area of the electron beam EB is performed is explained above, abnormality can be detected using the same method even when the control operation is performed to decrease the shot area of the electron beam EB. be.

The abnormality detection method and electron beam lithography apparatus 200 according to the sixth embodiment have, for example, the following features.

In the abnormality detection method according to the sixth embodiment, the shaping control circuit 230 deflects the shaping so that the electron beam EB changes from the first shot shape S1 and the first shot area A1 to the second shot shape S2 and the second shot area A2. The transient response includes a step of observing a transient response when performing a control operation to control the molding control circuit 202 and evaluating the control operation of the molding control circuit 230. Observe by obtaining . Therefore, according to the abnormality detection method according to the sixth embodiment, abnormalities in the control operation of the molding control circuit 230 can be detected with high accuracy. Furthermore, according to the abnormality detection method according to the sixth embodiment, abnormality detection can be performed with a simple configuration.

The electron beam lithography apparatus 200 includes an electron source 10, a shaping deflector 202 that shapes the electron beam emitted from the electron source 10, a first aperture 204a, a second aperture 204b, and an electron beam EB that irradiates the measurement target 6. an electronic detector 24 that detects an electronic signal generated by the electronic detector 24; a shaping control circuit 230 that controls the shaping deflector 202; and a signal detection circuit that detects the electronic signal with the electronic detector 24 and obtains a detection signal. A control operation in which the control circuit 36 and the shaping control circuit 230 control the shaping deflector 202 so that the electron beam changes from the first shot shape S1 and first shot area A1 to the second shot shape S2 and second shot area A2. It includes a control unit 40 (an example of an evaluation unit) that observes a transient response during the control operation and evaluates the control operation of the molding control circuit 230 based on a detection signal when the control operation is performed.

Therefore, in the electron beam lithography apparatus 200, abnormalities in the control operation of the shaping control circuit 230 can be detected with high accuracy. Further, in the electron beam lithography apparatus 200, by setting detection conditions (step S300), it is possible to automatically perform the processes from step S302 to step S310. Therefore, in the electron beam lithography apparatus 200, abnormalities in the control operation of the shaping control circuit 230 can be easily detected.

Note that the abnormality detection method according to the sixth embodiment can be used as an evaluation method for evaluating the overall control operation of the molding control circuit 230, similarly to the abnormality detection method according to the first embodiment.

6.3. Variations 6.3.1. First Modified Example In the sixth embodiment described above, the electron detector 24 detects the electron signal generated by irradiating the measurement target 6 with the electron beam and observes the detection signal, but the electron beam is detected by beam current detection. The detection signal may be observed (obtained) by detecting with the device 26. Also in this case, the same effects as in the sixth embodiment described above can be achieved. By changing the cross-sectional area of the electron beam with the shaping deflector 202, the beam current is also changed. Therefore, by detecting the electron beam with the beam current detector 26 and obtaining a detection signal, it is possible to detect an abnormality in the shaping deflector 202 similarly to the sixth embodiment described above.

6.3.2. Second Modified Example In the sixth embodiment described above, a case has been described in which a control operation is performed to change the shot shape and shot cross-sectional area of the electron beam, but only the shot cross-sectional area is changed without changing the shot shape of the electron beam. May be changed. Also in this case, the same effects as in the sixth embodiment described above can be achieved.

6.3.3. Third Modified Example The abnormality detection method according to the second embodiment can also be applied to the abnormality detection method according to the sixth embodiment described above.

Specifically, the shaping control circuit 230 performs a control operation to control the shaping deflector 202 so that the electron beam changes from the first shot shape S1 and first shot area A1 to the second shot shape S2 and second shot area A2. The control operation is performed a plurality of times, and the timing at which the detection signal is acquired is varied in the plurality of control operations. As a result, similar to the second embodiment, the waveforms of the detection signals as shown in FIGS. 13 and 14 are obtained. Therefore, the duration of waveform distortion (ringing time T) of the output signal of the shaping control circuit 230 can be known.

6.3.4. Fourth Modification The abnormality detection method according to the third embodiment can also be applied to the abnormality detection method according to the sixth embodiment described above.

Specifically, the shaping control circuit 230 performs a control operation to control the shaping deflector 202 so that the electron beam changes from the first shot shape S1 and first shot area A1 to the second shot shape S2 and second shot area A2. The control operation is performed a plurality of times, and the timing of acquiring the detection signal is the same in the plurality of control operations. As a result, similar to the third embodiment, the waveforms of the detection signals as shown in FIGS. 16 and 17 are obtained. Therefore, it is possible to reduce the influence of initial fluctuations of the shaping control circuit 230 and detection variations, and to accurately observe the signal strength to be observed when ringing occurs.

7. Seventh embodiment 7.1. Electron Beam Writing Apparatus The configuration of the electron beam writing apparatus according to the seventh embodiment is the same as the configuration of the electron beam writing apparatus 200 according to the sixth embodiment shown in FIG. 20, and illustration and description thereof will be omitted. Note that the electron beam control device according to the seventh embodiment may have the same configuration as the electron beam writing device 100 according to the first embodiment shown in FIG.

7.2. Abnormality Detection Method Next, an abnormality detection method according to the seventh embodiment will be described. Below, points different from the abnormality detection method according to the first embodiment described above will be explained, and explanations of similar points will be omitted.

In the abnormality detection method according to the first embodiment described above, an abnormality in the control operation of the deflection signal control circuit 34 is detected. In contrast, in the abnormality detection method according to the seventh embodiment, an abnormality in the control operation of the blanking control circuit 30 (an example of a blanking deflector control device) that switches on and off the electron beam is detected.

The abnormality detection method according to the seventh embodiment is to observe a transient response when the blanking control circuit 30 performs a control operation to control the blanking deflector 12 so that the electron beam is switched on and off. It includes a step of evaluating the control operation of the ranking control circuit 30, and the transient response is observed by detecting an electronic signal with the electronic detector 24 and obtaining a detection signal.

The blanking control circuit 30 has a configuration similar to that of the deflection signal control circuit 34 shown in FIG. 2, for example. Therefore, in the blanking control circuit 30, similarly to the deflection signal control circuit 34, for example, if the performance of elements such as transistors forming the output amplifier deteriorates, distortion such as ringing may occur in the output signal.

Therefore, in the abnormality detection method according to the seventh embodiment, a transient response is observed when the blanking control circuit 30 performs a control operation to control the blanking deflector 12 so that the electron beam is switched on and off. , detects an abnormality in the control operation (output) of the blanking control circuit 30.

FIG. 27 is a flowchart illustrating an example of the abnormality detection method according to the seventh embodiment. FIG. 28 is a diagram for explaining the abnormality detection method according to the seventh embodiment.

(1) Setting abnormality detection conditions (S400)
First, conditions for detecting an abnormality are set. Specifically, the on/off timing of the electron beam EB is set, the time and timing for observing the detection signal, etc. are set. The set conditions are stored in the storage device of the control unit 40.

The measurement object 6 for detecting an abnormality is not particularly limited as long as it generates an electronic signal when irradiated with the electron beam EB. The measurement object 6 is, for example, a metal film formed on a semiconductor wafer.

(2) Turn off the electron beam (S402)
Next, the blanking control circuit 30 performs a control operation to control the blanking deflector 12 so that the electron beam EB is turned off. This turns off the electron beam EB. The blanking control circuit 30 receives the output of the data control section 38 based on the control data and performs a control operation. The same applies to the control operation of the blanking control circuit 30, which will be described later.

(3) Observation start (S404)
Next, observation (acquisition) of the detection signal is started. The detection signal is obtained using the signal detection control circuit 36.

(4) Turn on the electron beam (S406)
Next, the blanking control circuit 30 performs a control operation to control the blanking deflector 12 so that the electron beam EB changes from an off state to an on state. This switches the electron beam EB from off to on. The blanking control circuit 30 controls the blanking deflector 12 so that the electron beam EB is kept on for a predetermined period of time.

(5) End of observation (S408)
After performing a control operation to control the blanking deflector 12 so that the electron beam EB changes from an off state to an on state, the acquisition (observation) of the detection signal ends. Through the above processing, it is possible to observe (continuously observe) the detection signal until a predetermined period of time elapses after the electron beam changes from the OFF state to the ON state.

The detection signal acquired using the signal detection control circuit 36 is processed by the control section 40. As a result, a waveform (waveform of the detection signal) indicating a change in the detection signal over time from when the electron beam EB changes from the OFF state to the ON state until a predetermined period of time has elapsed is generated. The waveform of this detection signal is displayed on, for example, a display unit (not shown) of the control unit 40 and stored in a storage device.

(6) Detection of abnormality (S410)
Next, an abnormality in the control operation of the blanking control circuit 30 is detected from the waveform of the detection signal.

29 to 31 are graphs showing the waveforms of detection signals until a predetermined time elapses after the electron beam changes from an off state to an on state. 29 and 30 are graphs showing the waveform of the detection signal observed when the waveform of the output signal of the blanking control circuit 30 is abnormal. FIG. 31 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the blanking control circuit 30 is normal.

Note that in the graphs shown in FIGS. 29 to 31, the horizontal axis indicates time t, and the vertical axis indicates the intensity I of the detection signal. Furthermore, in FIGS. 29 to 31, the intensity I _OFF is the intensity of the detection signal observed when the electron beam is turned off. Further, the intensity _ION is the intensity of the detection signal observed when the electron beam is turned on.

As shown in FIGS. 29 and 30, when there is an abnormality in the waveform of the output signal of the blanking control circuit 30, the waveform of the detection signal changes. Therefore, an abnormality in the control operation (output signal) of the blanking control circuit 30 can be detected by comparing the waveform of the detection signal observed in the above-mentioned measurement with the waveform of the detection signal during normal operation shown in FIG. I can do it.

When a slight distortion (see FIG. 46) occurs in the output signal of the blanking control circuit 30 due to ringing, the electron beam EB is turned on from the off state by the operation of the blanking deflector 12 that receives the output signal. Until the state is reached, the cross-sectional area changes slightly. As the cross-sectional area of the electron beam EB is repeatedly increased and decreased, the intensity of the electron signal emitted from the measurement object 6 changes. As a result, the effect of slight distortion occurring in the waveform of the output signal of the blanking control circuit 30 appears on the waveform of the detection signal.

Specifically, the waveform of the detection signal shown in FIG. 29 is observed when ringing as shown in FIG. 46 occurs in the waveform of the output signal of the blanking control circuit 30. In the waveform of the detection signal shown in FIG. 29, disturbance in the waveform due to ringing of the output signal is observed at the rising edge. As described above, it can be seen from the waveform of the detection signal shown in FIG. 29 that ringing occurs in the output signal of the blanking control circuit 30.

The waveform of the detection signal shown in FIG. 30 is observed when there is a delay in the response time of the blanking control circuit 30. The waveform of the detection signal shown in FIG. 30 has a delay in the time it takes for the intensity of the detection signal to reach the intensity _ION compared to the waveform of the detection signal during normal operation shown in FIG. 31 due to a delay in response time. . As described above, it can be seen from the waveform of the detection signal shown in FIG. 30 that there is a delay in response time.

The control unit 40 observes the transient response during the control operation based on the detection signal when the electron beam is changed from the OFF state to the ON state, and determines the control operation of the blanking control circuit 30. Detect anomalies. Specifically, the control unit 40 compares the waveform of the acquired detection signal with the waveform of a normal detection signal to detect an abnormality in the control operation of the blanking control circuit 30. Note that the abnormality may be detected by the user comparing the waveform of the detection signal with the waveform of the detection signal during normal operation.

The abnormality detection method and electron beam lithography apparatus according to the seventh embodiment have, for example, the following features.

The abnormality detection method according to the seventh embodiment is to observe a transient response when the blanking control circuit 30 performs a control operation to control the blanking deflector 12 so that the electron beam is switched on and off. It includes a step of evaluating the control operation of the ranking control circuit 30, and the transient response is observed by detecting an electronic signal with the electronic detector 24 and obtaining a detection signal. Therefore, according to the abnormality detection method according to the seventh embodiment, abnormalities in the control operation of the blanking control circuit 30 can be detected with high accuracy. Furthermore, according to the abnormality detection method according to the seventh embodiment, abnormality detection can be performed with a simple configuration.

The electron beam drawing apparatus according to the seventh embodiment includes an electron source 10, a blanking deflector 12 that turns on and off the electron beam emitted from the electron source 10, and a blanking deflector 12 that turns on and off the electron beam emitted from the electron source 10, and a blanking deflector 12 that turns on and off the electron beam emitted from the electron source 10. an electronic detector 24 that detects the electronic signal generated by the electronic detector 24; a blanking control circuit 30 that controls the blanking deflector 12; and a signal detection control that detects the electronic signal with the electronic detector 24 and obtains a detection signal. Observe the transient response during the control operation based on the circuit 36 and the detection signal when the blanking control circuit 30 performs a control operation to control the blanking deflector 12 so that the electron beam is switched on and off. and a control section 40 that evaluates the control operation of the blanking control circuit 30.

Therefore, in the electron beam lithography apparatus 200 according to the seventh embodiment, abnormalities in the control operation of the blanking control circuit 30 can be detected with high accuracy. Further, in the electron beam drawing apparatus 200, by setting detection conditions (step S400), the processes from step S402 to step S410 can be performed automatically. Therefore, in the electron beam writing apparatus 200, abnormalities in the control operation of the blanking control circuit 30 can be easily detected.

In recent years, the time per shot of an electron beam (shot time) has become shorter. Conventionally, when the shot time is long, the period during which the ringing of the output signal of the blanking control circuit 30 continues is short compared to the shot time and can be ignored. However, as the shot time becomes shorter, the effect of ringing becomes relatively larger. In the abnormality detection method according to the seventh embodiment, a slight distortion in the waveform of the output signal of the blanking control circuit 30 can be observed from the waveform of the detection signal, so it is extremely effective for evaluation when the shot time is short. be.

Note that the abnormality detection method according to the seventh embodiment can be used as an evaluation method for evaluating the overall control operation of the blanking control circuit 30, similarly to the abnormality detection method according to the first embodiment.

7.3. Variations 7.3.1. First Modified Example In the seventh embodiment described above, the electron detector 24 detects the electron signal generated by irradiating the measurement target 6 with the electron beam and observes the detection signal, but the electron beam is detected by beam current detection. The detection signal may be observed (obtained) by detecting with the device 26. Also in this case, the same effects as in the seventh embodiment described above can be achieved.

7.3.2. Second Modification In the seventh embodiment described above, a case has been described in which the control operation for switching the electron beam from an off state to an on state is evaluated, but when the electron beam is switched from an on state to an off state You may also evaluate the control operation for switching to . In this case as well, evaluation can be performed using the same method as in the seventh embodiment described above.

7.3.3. Third Modification The abnormality detection method according to the second embodiment can also be applied to the abnormality detection method according to the seventh embodiment described above.

Specifically, the blanking control circuit 30 performs a control operation to control the blanking deflector 12 multiple times so that the electron beam changes from an off state to an on state, and in the multiple control actions, the detection signal is Different timing of acquisition. As a result, similar to the second embodiment, the waveforms of the detection signals as shown in FIGS. 13 and 14 are obtained. Therefore, the duration of waveform distortion (ringing time T) of the output signal of the blanking control circuit 30 can be known.

7.3.4. Fourth Modification The abnormality detection method according to the third embodiment can also be applied to the abnormality detection method according to the seventh embodiment described above.

Specifically, the blanking control circuit 30 performs a control operation to control the blanking deflector 12 multiple times so that the electron beam changes from an off state to an on state, and in the multiple control actions, the detection signal is The acquisition timing is the same. As a result, similar to the third embodiment, the waveforms of the detection signals as shown in FIGS. 16 and 17 are obtained. Therefore, it is possible to reduce the influence of initial fluctuations of the blanking control circuit 30 and detection variations, and to accurately observe the signal strength to be observed when ringing occurs.

8. Eighth embodiment 8.1. Electron Beam Drawing Apparatus Next, an electron beam drawing apparatus according to an eighth embodiment will be described with reference to the drawings. FIG. 32 is a diagram showing the configuration of an electron beam lithography apparatus 300 according to the eighth embodiment. Hereinafter, in the electron beam lithography apparatus 300 according to the eighth embodiment, members having the same functions as the constituent members of the electron beam lithography apparatus 100 according to the first embodiment and the electron beam lithography apparatus 200 according to the sixth embodiment will be described. The same reference numerals are given, and detailed explanation thereof will be omitted.

As shown in FIG. 32, the electron beam drawing apparatus 300 includes an astigmatism corrector 302, an astigmatism correction circuit 330 (an example of an astigmatism corrector control device) that controls the astigmatism corrector 302, including.

The electron beam drawing apparatus 300 can correct astigmatism using the astigmatism corrector 302.

FIGS. 33 and 34 are diagrams for explaining how astigmatism is corrected. The astigmatism corrector 302 can independently correct astigmatism for two axes, the X-axis and the Y-axis, as shown in FIGS. 33 and 34, for example. Specifically, in the example shown in FIG. 33, the astigmatism corrector 302 corrects astigmatism along the Y-axis so that the elliptical electron beam EB with its long axis along the X-axis becomes a circle. Introduce and correct. In the example shown in FIG. 34, the astigmatism corrector 302 introduces and corrects astigmatism along the X-axis so that the elliptical electron beam having a long axis along the Y-axis becomes a circle. do.

The magnitude of astigmatism changes depending on the position of the electron beam EB. Therefore, the amount of astigmatism correction by the astigmatism corrector 302 is changed depending on the position of the electron beam EB. Note that even if the astigmatism correction amount is changed, the beam current of the electron beam EB does not change.

In the electron beam lithography apparatus 300, the data control section 38 receives the lithography data from the control section 40 and controls the blanking control circuit 30, the lens control circuit 32, the deflection signal control circuit 34, the shaping control circuit 230, and the astigmatism control circuit. Controls the correction circuit 330. Further, as will be described later, the control unit 40 also functions as an abnormality detection unit (an evaluation unit that evaluates the control operation of the astigmatism correction circuit 330) that detects an abnormality in the control operation of the astigmatism correction circuit 330. .

Next, the operation when the electron beam drawing apparatus 300 draws a pattern on the sample S will be described.

In the electron beam drawing apparatus 300, the electron beam emitted from the electron source 10 is focused onto the sample S by the electron lens 14 and the electron lens 20. Here, when the drawing data (pattern data) is stored in the storage device of the control unit 40, the stored drawing data is processed by the data control unit 38, and the blanking control circuit 30, the lens control circuit 32, and the deflection signal are processed. The signal is sent to the control circuit 34, the shaping control circuit 230, and the astigmatism correction circuit 330. The electron beam is shaped by the shaping deflector 202, the first aperture 204a, and the second aperture 204b, turned on and off by the blanking deflector 12, and deflected to a predetermined position on the sample S by the beam deflector 18. At this time, the astigmatism corrector 302 corrects astigmatism. By combining such movement of the electron beam and movement of the stage 22, a pattern based on the drawing data can be written.

8.2. Abnormality Detection Method Next, an abnormality detection method according to the eighth embodiment will be described. Below, points that are different from the example of the abnormality detection method according to the first embodiment described above will be explained, and descriptions of similar points will be omitted.

In the abnormality detection method according to the first embodiment described above, an abnormality in the control operation of the deflection signal control circuit 34 is detected. In contrast, in the abnormality detection method according to the eighth embodiment, abnormality in the control operation of the astigmatism correction circuit 330 is detected.

The abnormality detection method according to the eighth embodiment includes a control operation in which the astigmatism correction circuit 330 controls the astigmatism corrector 302 so that the astigmatism correction amount changes from the first correction amount to the second correction amount. The transient response includes the step of observing the transient response when performing this and evaluating the control operation of the astigmatism correction circuit 330. Observe. Note that the first correction amount and the second correction amount are different in correction amount.

The astigmatism correction circuit 330 has, for example, the same configuration as the deflection signal control circuit 34 shown in FIG. 2. Therefore, in the astigmatism correction circuit 330, as in the deflection signal control circuit 34, for example, if the performance of elements such as transistors forming the output amplifier deteriorates, distortion such as ringing may occur in the output signal. .

Therefore, in the abnormality detection method according to the eighth embodiment, the astigmatism correction circuit 330 controls the astigmatism corrector 302 so that the astigmatism correction amount changes from the first correction amount to the second correction amount. The transient response when the control operation is performed is observed, and an abnormality in the control operation (output) of the astigmatism correction circuit 330 is detected.

FIG. 35 is a flowchart illustrating an example of an abnormality detection method according to the eighth embodiment. FIG. 36 is a diagram for explaining the abnormality detection method according to the eighth embodiment. The control operation of the astigmatism correction circuit 330 in the X direction will be described below.

(1) Setting abnormality detection conditions (S500)
First, conditions for detecting an abnormality are set. Specifically, the steps include aligning the mark 2, setting the astigmatism correction amount in the initial state (first correction amount), setting the astigmatism correction amount after change (second correction amount), and adjusting the detection signal. Set the observation time and timing. The set conditions are stored in the storage device of the control unit 40.

Even if the astigmatism correction amount is changed, the amount of current of the electron beam EB irradiated onto the object to be measured does not change. Therefore, for example, when the measurement object 6 shown in FIG. 22 is used, even if the astigmatism correction amount is changed, the amount of electronic signals does not change. Therefore, in the eighth embodiment, mark 2 is used as the measurement target.

In the initial state, the astigmatism correction amount is set as the first correction amount, and the electron beam EB is set to be placed in the region 2a. At this time, the position of the electron beam EB is set near the boundary between the region 2a and the region 2c. Specifically, when the electron beam EB is changed from the first correction amount to the second correction amount, the electron beam EB is set at a position straddling the region 2c. Thereby, a change in the correction amount can be observed as a change in the electronic signal, that is, a change in the detection signal.

The position of the electron beam EB in the initial state is not limited to the position shown in FIG. 36, and when the astigmatism correction amount is changed from the first correction amount to the second correction amount, the change in the correction amount is detected as It suffices if it is set at a position where it can be observed as a change in . For example, as shown in FIG. 37, the position of the electron beam EB in the initial state may be set to the region 2b of the mark 2. In this way, the initial state may be set to a position that straddles another area, for example, when the astigmatism correction amount is changed from the first correction amount to the second correction amount.

(2) Set the astigmatism correction amount as the first correction amount (S502)
Next, the astigmatism correction circuit 330 performs a control operation to control the astigmatism corrector 302 so that the astigmatism correction amount becomes the first correction amount. As a result, astigmatism is introduced into the electron beam EB by the first correction amount. The astigmatism correction circuit 330 receives the output of the data control section 38 based on the control data and performs a control operation. The same applies to the control operation of the astigmatism correction circuit 330, which will be described later.

(3) Observation start (S504)
Next, observation (acquisition) of the detection signal is started. The detection signal is obtained using the signal detection control circuit 36.

(4) Set the astigmatism correction amount as the second correction amount (S506)
Next, the astigmatism correction circuit 330 performs a control operation to control the astigmatism corrector 302 so that the astigmatism correction amount changes from the first correction amount to the second correction amount. As a result, the astigmatism introduced into the electron beam EB changes from the first correction amount to the second correction amount. The astigmatism correction circuit 330 controls the astigmatism corrector 302 so that the astigmatism correction amount is maintained at the second correction amount for a predetermined period of time.

(5) End of observation (S508)
After performing a control operation to control the astigmatism corrector 302 so that the astigmatism correction amount changes from the first correction amount to the second correction amount, the acquisition (observation) of the detection signal is ended. Through the above processing, it is possible to observe (continuously observe) the detection signal until a predetermined period of time elapses after the astigmatism correction amount changes from the first correction amount to the second correction amount.

The detection signal acquired using the signal detection control circuit 36 is processed by the control section 40. As a result, a waveform (waveform of the detection signal) indicating a change in the detection signal over time from when the astigmatism correction amount is changed from the first correction amount to the second correction amount until a predetermined period of time has elapsed is generated. The waveform of this detection signal is displayed on, for example, a display unit (not shown) of the control unit 40 and stored in a storage device.

(6) Detection of abnormality (S510)
Next, an abnormality in the control operation of the astigmatism correction circuit 330 is detected from the waveform of the detection signal.

38 to 40 are graphs showing the waveforms of detection signals until a predetermined time elapses after the astigmatism correction amount changes from the first correction amount to the second correction amount. 38 and 39 are graphs showing the waveform of the detection signal observed when the waveform of the output signal of the astigmatism correction circuit 330 is abnormal. FIG. 40 is a graph showing the waveform of the detection signal observed when the waveform of the output signal of the astigmatism correction circuit 330 is normal.

Note that in the graphs shown in FIGS. 38 to 40, the horizontal axis indicates time t, and the vertical axis indicates the intensity I of the detection signal. Further, in FIGS. 38 to 40, the intensity I ₁ is the intensity of the detection signal observed when the astigmatism correction amount is set to the first correction amount. Moreover, the intensity I ₂ is the intensity of the detection signal observed when the astigmatism correction amount is set to the second correction amount.

As shown in FIGS. 38 and 39, when there is an abnormality in the waveform of the output signal of the astigmatism correction circuit 330, the waveform of the detection signal changes. Therefore, an abnormality in the control operation (output signal) of the astigmatism correction circuit 330 is detected by comparing the waveform of the detection signal observed in the above-mentioned measurement with the waveform of the detection signal during normal operation shown in FIG. be able to.

When the output signal of the astigmatism correction circuit 330 has a slight distortion due to ringing (see FIG. 46), the operation of the astigmatism corrector 302 that receives the output signal causes the electron beam EB to undergo the first correction. The size in the X direction changes slightly until the amount changes from the amount to the second correction amount. Due to this variation in the size of the electron beam EB in the X direction, the proportion of the area 2c irradiated with the entire irradiation area of the electron beam EB varies. As a result, the intensity of the detection signal changes, so that the influence of slight distortion occurring in the waveform of the output signal of the astigmatism correction circuit 330 appears on the waveform of the detection signal.

Specifically, the waveform of the detection signal shown in FIG. 38 is observed when ringing as shown in FIG. 46 occurs in the waveform of the output signal of the astigmatism correction circuit 330. In the waveform of the detection signal shown in FIG. 38, a peak due to ringing of the output signal is observed at the rising edge. As described above, it can be seen from the waveform of the detection signal shown in FIG. 38 that ringing occurs in the output signal of the astigmatism correction circuit 330.

The waveform of the detection signal shown in FIG. 39 is observed when there is a delay in the response time of the astigmatism correction circuit 330. The waveform of the detection signal shown in FIG. 39 has a delay in the time it takes for the intensity of the detection signal to reach the intensity _I2 compared to the waveform of the detection signal during normal operation shown in FIG. 40 due to a delay in response time. . As described above, it can be seen from the waveform of the detection signal shown in FIG. 39 that there is a delay in response time.

The control unit 40 observes the transient response during the control operation based on the detection signal when the control operation is performed to change the astigmatism correction amount from the first correction amount to the second correction amount, and corrects the astigmatism. An abnormality in the control operation of the correction circuit 330 is detected. Specifically, the control unit 40 performs processing to detect an abnormality in the control operation of the astigmatism correction circuit 330 by comparing the waveform of the acquired detection signal with the waveform of a normal detection signal. Note that the abnormality may be detected by the user comparing the waveform of the detection signal with the waveform of the detection signal during normal operation.

Note that although the case where an abnormality in the control operation of the astigmatism correction circuit 330 in the X direction is detected has been described above, an abnormality in the control operation in the Y direction of the astigmatism correction circuit 330 can also be detected using a similar method. be able to.

Furthermore, in the above description, the case where the size of the electron beam EB in the X direction increases when the astigmatism correction amount is changed from the first correction amount to the second correction amount, but the astigmatism correction amount When changing from the first correction amount to the second correction amount, the size of the electron beam EB in the X direction may be reduced. In this case as well, abnormalities can be detected using a similar method.

The abnormality detection method and electron beam lithography apparatus 300 according to the eighth embodiment have, for example, the following features.

The abnormality detection method according to the eighth embodiment includes a control operation for controlling the astigmatism corrector 302 in the astigmatism correction circuit 330 so that the amount of correction of astigmatism changes from the first correction amount to the second correction amount. The transient response is observed by detecting an electronic signal with the electronic detector 24 and obtaining a detection signal. do. Therefore, according to the abnormality detection method according to the eighth embodiment, abnormalities in the control operation of the astigmatism correction circuit 330 can be detected with high accuracy. Furthermore, according to the abnormality detection method according to the eighth embodiment, abnormality detection can be performed with a simple configuration.

The electron beam lithography apparatus according to the eighth embodiment includes an electron source 10, an astigmatism corrector 302 that corrects astigmatism of the electron beam emitted from the electron source 10, and an astigmatism corrector 302 that corrects astigmatism of the electron beam emitted from the electron source 10. The electronic detector 24 detects the electronic signal generated by When the signal detection control circuit 36 and the astigmatism correction circuit 330 perform a control operation to control the astigmatism corrector 302 so that the astigmatism correction amount changes from the first correction amount to the second correction amount. and a control section 40 that observes a transient response during a control operation based on the detection signal of and evaluates the control operation of the astigmatism correction circuit 330.

Therefore, in the electron beam writing apparatus 300 according to the eighth embodiment, abnormalities in the control operation of the astigmatism correction circuit 330 can be detected with high accuracy. Further, in the electron beam writing apparatus 300, by setting detection conditions (step S500), the processes of steps S502 to S510 can be performed automatically. Therefore, in the electron beam writing apparatus 300, abnormalities in the control operation of the astigmatism correction circuit 330 can be easily detected.

Note that the abnormality detection method according to the eighth embodiment can be used as an evaluation method for evaluating the overall control operation of the astigmatism correction circuit 330, similarly to the abnormality detection method according to the first embodiment.

8.3. Variations 8.3.1. First Modified Example The abnormality detection method according to the fourth embodiment can also be applied to the abnormality detection method according to the eighth embodiment described above. That is, as a measurement object, a measurement object 4 having two regions (area 4a and region 4b) in which the intensity of the detection signal observed when irradiated with the electron beam shown in FIG. 18 under the same irradiation conditions is different is used. Good too.

FIG. 41 is a diagram for explaining an example of an abnormality detection method of the astigmatism correction circuit 330 using the measurement object 4. As shown in FIG.

As shown in FIG. 41, the position of the electron beam EB is set near the boundary between regions 4a and 4b, and the astigmatism correction amount is set as the first correction amount. The astigmatism correction circuit 330 performs a control operation to control the astigmatism corrector 302 so that the amount becomes the second correction amount. At this time, if a slight distortion due to ringing occurs in the output signal of the astigmatism correction circuit 330, the operation of the astigmatism corrector 302 that receives the output signal causes the electron beam EB to change from the first correction amount. The size in the X direction changes slightly until the amount changes to the second correction amount. Due to this variation in the size of the electron beam EB in the X direction, the ratio of irradiation of the region 4b in the entire irradiation region of the electron beam EB varies. As a result, the intensity of the detection signal changes, so that the influence of slight distortion occurring in the waveform of the output signal of the astigmatism correction circuit 330 appears on the waveform of the detection signal.

According to the first modification, an abnormality in the control operation of the astigmatism correction circuit 330 can be detected similarly to the abnormality detection method according to the eighth embodiment described above.

8.3.2. Second Modified Example The abnormality detection method according to the fifth embodiment can also be applied to the abnormality detection method according to the eighth embodiment described above. That is, the electron beam may be detected by the beam current detector 26 and the detection signal may be observed (obtained).

FIG. 42 is a diagram for explaining how the electron beam EB is detected by the beam current detector 26 and the detection signal is observed.

As shown in FIG. 42, from a state where the position of the electron beam EB is the tip of the knife edge 27 and the astigmatism correction amount is the first correction amount, the astigmatism correction amount is changed from the first correction amount to the first correction amount. The astigmatism correction circuit 330 performs a control operation to control the astigmatism corrector 302 so that the amount of correction becomes 2. At this time, the electron beam (beam current) that is incident on the beam current detector 26 (Faraday cup) without being obstructed by the knife edge 27 is detected by the beam current detector 26 and a detection signal is observed (obtained). As a result, the waveform of the detected signal to be observed is affected by the slight distortion (ringing, etc.) that occurs in the waveform of the output signal of the astigmatism correction circuit 330, as in the eighth embodiment described above. appears in

According to the second modification, an abnormality in the control operation of the astigmatism correction circuit 330 can be detected similarly to the abnormality detection method according to the eighth embodiment described above.

8.3.3. Third Modified Example The abnormality detection method according to the second embodiment can also be applied to the abnormality detection method according to the eighth embodiment described above.

Specifically, the astigmatism correction circuit 330 performs a control operation to control the astigmatism corrector 302 multiple times so that the astigmatism correction amount changes from the first correction amount to the second correction amount. In the control operation, the timing of acquiring the detection signal is made different. As a result, similar to the second embodiment, the waveforms of the detection signals as shown in FIGS. 13 and 14 are obtained. Therefore, the duration of waveform distortion (ringing time T) of the output signal of the astigmatism correction circuit 330 can be known.

8.3.4. Fourth Modification The abnormality detection method according to the third embodiment can also be applied to the abnormality detection method according to the eighth embodiment described above.

Specifically, the astigmatism correction circuit 330 performs a control operation to control the astigmatism corrector 302 multiple times so that the astigmatism correction amount changes from the first correction amount to the second correction amount. In the control operations, the timing of acquiring the detection signal is the same. As a result, similar to the third embodiment, the waveforms of the detection signals as shown in FIGS. 16 and 17 are obtained. Therefore, it is possible to reduce the influence of initial fluctuations of the astigmatism correction circuit 330 and detection variations, and to accurately observe the signal strength to be observed when ringing occurs.

Note that the above-described embodiments and modifications are merely examples, and the present invention is not limited thereto. For example, each embodiment and each modification can be combined as appropriate.

The present invention includes configurations that are substantially the same as those described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objectives and effects). Further, the present invention includes a configuration in which non-essential parts of the configuration described in the embodiments are replaced. Further, the present invention includes a configuration that has the same effects or a configuration that can achieve the same objective as the configuration described in the embodiment. Further, the present invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

2... Mark, 2a... Area, 2b... Area, 2c... Area, 3... Substrate, 4... Measurement object, 4a... Area, 4b... Area, 6... Measurement object, 10... Electron source, 12... Blanking deflection 14...Electron lens, 16...Slit, 18...Beam deflector, 20...Electron lens, 22...Stage, 24...Electron detector, 26...Beam current detector, 27...Knife edge, 28...High voltage power supply, 30 ...Blanking control circuit, 32... Lens control circuit, 34... Deflection signal control circuit, 36... Signal detection control circuit, 38... Data control section, 40... Control section, 100... Electron beam drawing device, 200... Electron beam drawing device , 202... Shaping deflector, 204a... First aperture, 204b... Second aperture, 230... Shaping control circuit, 300... Electron beam writing device, 302... Astigmatism corrector, 330... Astigmatism correction circuit, 341... D/A conversion section, 342... Output amplifier, 343... Monitor amplifier, 344... A/D conversion section, 361... First stage amplifier, 362... Signal switching section, 363... Amplifying amplifier, 364... Gain switching section, 365... A/ D conversion section, 366... Level/gain control section, 367... Timing adjustment section

Claims (8)

A charged particle source, a shaping deflector and an aperture that shape a charged particle beam emitted from the charged particle source, and a detection device that detects a charged particle beam or a signal generated when a measurement target is irradiated with the charged particle beam. A method for evaluating the control operation of the shaping deflector control device in a charged particle beam device comprising: a shaping deflector controller;
When the shaping deflector control device performs a control operation to control the shaping deflector so that the charged particle beam changes from a first cross-sectional area to a second cross-sectional area different in size from the first cross-sectional area. a step of observing a transient response and evaluating a control operation of the shaping deflector control device;
The transient response is determined by the charged particle beam until a predetermined time elapses after the charged particle beam changes from the first cross-sectional area to the second cross-sectional area, or the detected signal obtained by detecting the signal with the detector. An evaluation method in which an abnormality in a waveform of an output signal of the shaping deflector control device is detected from a waveform showing a change over time . In claim 1,
In the step of evaluating the control operation,
A rectangular charged particle beam whose length in a first direction is shorter than the length in a second direction perpendicular to the first direction is fixed, and the length in the first direction is changed. By observing a transient response when the shaping deflector control device performs a control operation to control the shaping deflector so as to change the shaping deflector from the first cross-sectional area to the second cross-sectional area, An evaluation method for evaluating molding in the first direction in a control device. In claim 1,
In the step of evaluating the control operation,
If the intensity of the detection signal when the charged particle beam has the first cross-sectional area is _IA1 , and the intensity of the detection signal when the charged particle beam has the second cross-section is _IA2 , then the An evaluation method that detects an abnormality in the waveform of the output signal of the shaping deflector control device from a change in the intensity of the detection signal from _IA1 to _IA2 . In claim 3,
In the step of evaluating the control operation,
An evaluation method in which a peak of the intensity of the detection signal is observed during a period from when the intensity of the detection signal increases from I _A1 to I _A2 . a charged particle source;
a shaping deflector and an aperture for shaping the charged particle beam emitted from the charged particle source;
a detector that detects a charged particle beam or a signal generated when a measurement target is irradiated with the charged particle beam;
a shaping deflector control device that controls the shaping deflector;
a detection signal acquisition unit that acquires a detection signal obtained by detecting the charged particle beam or the signal with the detector;
When the shaping deflector control device performs a control operation to control the shaping deflector so that the charged particle beam changes from a first cross-sectional area to a second cross-sectional area different in size from the first cross-sectional area. an evaluation unit that observes a transient response during the control operation based on the detection signal and evaluates the control operation of the shaping deflector control device;
including ;
The evaluation unit calculates an output signal of the shaping deflector control device from a waveform indicating a change in the detection signal over time from when the charged particle beam changes from the first cross-sectional area to the second cross-sectional area and a predetermined time elapses. A charged particle beam device that observes a transient response during the control operation by detecting an abnormality in the waveform of the charged particle beam. In claim 5 ,
The evaluation department is
A rectangular charged particle beam whose length in a first direction is shorter than the length in a second direction perpendicular to the first direction is fixed, and the length in the first direction is changed. The control operation may be performed based on the detection signal when the shaping deflector control device performs a control operation to control the shaping deflector so as to change the shaping deflector from the first cross-sectional area to the second cross-sectional area. A charged particle beam device that evaluates shaping in the first direction in the shaping deflector control device by observing a transient response over time. In claim 5 ,
The evaluation department is
If the intensity of the detection signal when the charged particle beam has the first cross-sectional area is _IA1 , and the intensity of the detection signal when the charged particle beam has the second cross-section is _IA2 , then the A charged particle beam device that detects an abnormality in the waveform of the output signal of the shaping deflector control device based on a change in the intensity of the detection signal from _IA1 to _IA2 . In claim 7 ,
The evaluation unit is a charged particle beam device in which the evaluation unit observes the peak of the intensity of the detection signal during a period from when the intensity of the detection signal becomes _IA1 to _IA2 .

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