JP4206296B2 - Pattern evaluation method and device manufacturing method using the method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for evaluating a sample having a pattern formed by a line having a minimum line width of 0.1 μm or less with high accuracy and high throughput.
[0002]
[Prior art]
It is known that a high-resolution electron beam can be irradiated onto a sample when a negative voltage is applied to the wafer. Furthermore, a defect inspection method with a high throughput using a multi-beam is also known, and a technique for fixing a wafer with an electrostatic chuck is also known.
[0003]
[Problems to be solved by the invention]
However, a specific method for applying a negative voltage to the wafer and operating the electrostatic chuck has not been established. There was no established theory regarding the relationship between loading and unloading and the timing of voltage application. In particular, the problem was that the vibration at the time of opening and closing the gate valve for keeping the working chamber (sample chamber) in a vacuum state adversely affects the accuracy of the wafer loading position, and electrostatic The chuck was that it took a certain amount of time to be completely released (free) after being given a signal to remove the wafer. Further, there is a problem that, when the negative voltage is turned on / off with respect to the wafer, if the voltage is turned on / off at a large slew rate, the transistor may be destroyed depending on the layer. The present invention has been made in view of these problems. The vibration during the operation of the gate valve does not adversely affect the accuracy when loading the wafer, and the electrostatic chuck can be safely operated without destroying the wafer device. Another object of the present invention is to provide a pattern evaluation method that can be quickly removed.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, according to the present invention,
A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber for pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading the sample, a gate valve for partitioning the sample chamber and the spare chamber, and a spare chamber for transporting the sample In a device having a transport arm, an electrostatic chuck provided in the sample chamber for fixing the sample, and a negative voltage power source for applying to the sample, the gate valve is opened, and the sample is preliminarily prepared using the transport arm. Taking it out of the chamber and placing it on the electrostatic chuck in the sample chamber through the gate valve;
b. In a state where the electrode of the electrostatic chuck is grounded or a predetermined voltage is applied, applying a negative voltage to the sample and fixing it to the electrostatic chuck;
c. After the sample is fixed to the electrostatic chuck, the step of pulling the transfer arm from the sample chamber through the gate valve to the preliminary chamber side;
d. Closing the gate valve;
e. Irradiating the sample with an electron beam after vibration generated when the gate valve is closed is sufficiently small, and starting a pattern evaluation;
A pattern evaluation method is provided in which the step b is preceded by the step d.
[0005]
Also according to the invention,
A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber for pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading the sample, a gate valve for partitioning the sample chamber and the spare chamber, and a spare chamber for transporting the sample In a device having a transport arm, an electrostatic chuck provided on a stage in the sample chamber for fixing the sample, and a negative voltage power source for applying the sample to the sample, a static voltage is applied to the sample by applying a negative voltage to the sample. Irradiating a sample fixed on the electric chuck with an electron beam, detecting secondary electrons and evaluating a pattern;
b. After the evaluation of the sample is completed, a step of deflecting the electron beam with a deflector and blanking so as not to come to the sample surface;
c. Moving the stage to a position to unload the sample;
d. Cutting off the negative voltage applied to the sample;
e. Opening the gate valve, placing the transfer arm from the preliminary chamber into the sample chamber, and removing the sample from the sample chamber;
f. Next, removing the sample to be evaluated from the preliminary chamber and placing it on the electrostatic chuck in the sample chamber;
There is also provided a pattern evaluation method characterized by comprising:
[0006]
Also according to the invention,
A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber that performs pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading a sample, a first gate valve that partitions the sample chamber and the spare chamber, and a spare chamber and an atmospheric chamber are partitioned. In an apparatus having a second gate valve and a transfer arm provided in a preliminary chamber for transferring a sample, the sample in the sample chamber is irradiated with an electron beam, and secondary electrons are detected to perform pattern evaluation. Steps,
b. A step of temporarily stopping the movement of the stage after the evaluation of the stripe under pattern evaluation is completed;
c. Bringing the preparatory chamber to atmospheric pressure before removing the evaluated sample into the atmospheric chamber;
d. Opening the second gate valve and taking the evaluated sample into the atmospheric chamber;
e. Next, carry the sample to be evaluated into the preliminary chamber;
f. Closing the second gate valve and evacuating the reserve chamber;
g. A step of confirming that the degree of vacuum in the preliminary chamber is substantially constant;
h. Starting the evaluation from the stripe to be evaluated next for the sample under evaluation;
There is also provided a pattern evaluation method characterized by comprising:
[0007]
In the pattern evaluation method according to any one of the above, the electron beam emitted from a single electron beam emission region of a single electron gun is separated by a plurality of openings, and a reduced image of the plurality of openings is displayed on the sample surface. Pattern evaluation is performed by continuously moving the sample stage along the stripe while scanning a plurality of separated electron beams in a uniaxial direction, and a reduced image of the opening is formed on the longitudinal axis of the stripe. All of the image intervals when projected onto can be made equal.
[0008]
Alternatively, in the pattern evaluation method according to any one of the above, the electron beam is emitted from a single electron beam emission region of a single electron gun and then shaped into a belt-like beam at a linear opening, This strip-shaped beam is imaged on the sample, and the strip-shaped beam is electrically scanned in a direction perpendicular to itself, while the sample stage is continuously moved in a direction parallel to the strip-shaped beam to perform pattern evaluation. May be.
[0009]
According to the present invention, there is further provided a device manufacturing method characterized by using any of the evaluation methods described above.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram for explaining an embodiment of the present invention. The pattern on the wafer 5 is evaluated by irradiating an electron beam in the working chamber (sample chamber) 1. A robot 6 is placed in the spare room 2. The robot 6 takes out the wafer 5 pre-aligned in another spare chamber 3 and loads it into the working chamber 1. The spare chambers 2 and 3 and the spare chamber 2 and the working chamber 1 are partitioned by gate valves 9 and 8, respectively, and the atmosphere and the spare chamber 3 are also partitioned by a gate valve 13. An electrostatic chuck (not shown) that partially contacts the back surface of the wafer 5 is attached to the load arm (transfer arm) 7 of the robot 6. The loading and unloading of the wafer 5 is performed according to the following procedure.
[0011]
1. The preliminary chamber 3 is evacuated to a high vacuum, and the gate valve 9 is opened.
[0012]
2. The wafer 5 is chucked by an electrostatic chuck attached to the load arm 7 of the robot 6 and brought into the spare chamber 2.
[0013]
3. The gate valve 9 is closed.
[0014]
4). The gate valve 8 is opened, the wafer 5 is brought into the working chamber 1 and placed on the electrostatic chuck 10 attached to the stage (sample stage) 4 at the load position. Voltages are respectively applied from the control power supplies 11 and 12 to the wafer 5 transferred onto the stage 4 and the electrostatic chuck 10 on which the wafer 5 is mounted. The application of voltage is performed as shown in FIG. First, a voltage rising from zero to +3 kv is applied to the electrostatic chuck 10 as indicated by the dotted line 24 from the time T _{0 to} the time T ₁ .
[0015]
5. When the voltage applied to the electrostatic chuck 10 reaches 3 kv, the wafer 5 is attracted to the electrostatic chuck 10 (time T ₁ ).
[0016]
6). Thereafter, the voltage applied to the electrostatic chuck 10 is reduced from +3 kv to −1 kv from time T ₁ to time T _{2 as} indicated by a dotted line 24, and is constant at a voltage of −1 kv after time T _2. It is controlled to become. On the other hand, the wafer 5, as shown by the solid line 23, from the point of time T _1, slide into applying a negative voltage increases in slope slow. When it reaches −4 kv at time T ₂ , it is controlled to be constant at −4 kv thereafter. Therefore, after time T ₁ , a voltage difference of 3 kv is constantly applied between the electrostatic chuck 10 and the wafer 5. After time T ₂ , the electrostatic chuck attached to the load arm 7 is removed from the wafer 5, and the load arm 7 is pulled out to the preliminary chamber 2 through the gate valve 8.
[0017]
7). The gate valve 8 is closed.
As described above, by performing the step 7 after the step 5, the wafer 5 is already attracted to the electrostatic chuck 10 when the gate valve 8 is closed. Therefore, even if vibration due to the closing operation of the gate valve 8 occurs, the relative position between the wafer 5 and the electrostatic chuck 10 is shifted, and the result of the pre-alignment is not impaired.
[0018]
8). After the vibration of the gate valve 8 is sufficiently cured, the evaluation of the wafer 5 is started.
[0019]
9. When a new wafer is put into the spare chamber during the evaluation of one wafer, the gate valve operation is started after waiting for the evaluation of the stripe under evaluation to be completed.
[0020]
10. Nitrogen gas is put into the preliminary chamber 3 until 1 atm.
[0021]
11. Open the gate valve 13 and insert a new wafer.
[0022]
12 The gate valve 13 is closed and the preliminary chamber 3 is evacuated. Since the spare chamber 3 is a small-volume chamber in which a single wafer and the load arm 7 can barely enter, the evacuation is completed within a few minutes.
[0023]
13. When the degree of vacuum improves and the rate of change in the degree of vacuum falls below a predetermined value, pre-alignment of a new wafer and evaluation of a wafer whose evaluation has been interrupted are performed.
[0024]
14 When the evaluation of the wafer is completed, a voltage that deflects the beam is applied to the deflector 49 in FIG. As a result, the electron beam is deflected off the optical axis, absorbed by the NA opening 51, and is not irradiated on the sample 41. (Description of FIG. 3 will be made later.)
[0025]
15. The stage is moved to a position where the wafer can be unloaded.
[0026]
16. The voltage of the electrostatic chuck 10 and the voltage generated by the power source for generating a deceleration electric field are gradually set to 0v. As shown by the dotted line 22 in the time chart of FIG. 2A, the voltage of the electrostatic chuck 10 is set from −1 kv to 0 v from time t ₁ to time t ₂ . The voltage from the power source for generating a deceleration electric field for applying a voltage to the wafer 5 is also set from -4 kv to 0 v from time t ₁ to time t ₂ as indicated by the solid line 21 in the time chart of FIG.
[0027]
17. The gate valve 8 is opened and the wafer 5 is taken out.
(While opening the gate valve 8, the wafer 5 can be completely removed from the electrostatic chuck 10, and the wafer 5 can be taken out safely.)
[0028]
18. The gate valve 9 is opened, and the evaluated wafer 5 is taken out to the preliminary chamber 3.
[0029]
19. Preparations are made to put the next wafer, which has been put in the preliminary chamber 3, into the working chamber 1.
[0030]
20. Returning to step 2, the following steps 2 to 19 are repeated.
FIG. 3 is a schematic diagram of the electron optical system of the electron beam apparatus used in the evaluation method of the present invention described above. An electron beam emitted from a single electron beam emission region of a single electron gun 31 is converged by a condenser lens 32 and then separated into a plurality of beams by a multi-aperture plate 33 having a plurality of apertures, and an NA aperture. 51, and is reduced by the reduction lens 34. Reduced images of a plurality of apertures are irradiated onto the sample 41 such as a wafer through the objective lens 40. Reference numeral 35 denotes a first scanning electrostatic deflector, 36 denotes an E × B pre-deflector, 37 denotes an E × B electromagnetic deflector, 38 denotes an E × B electrostatic deflector, and 39 denotes a second scanning. Electrostatic deflector. While scanning the plurality of separated electron beams in the uniaxial direction, the pattern on the sample 41 is evaluated by continuously moving the sample stage on which the sample 41 is placed along the stripe. The reduced images of the plurality of apertures irradiated on the sample 41 are configured such that the image intervals when projected onto the longitudinal axis of the stripe are all equal.
[0031]
Instead of the multi-aperture plate 33, a member having a linear opening may be arranged to shape the electron beam into a belt-like beam. In this case, the band-shaped beam is imaged on the sample 41 in a band shape. At the time of pattern evaluation, while the band-shaped beam is electrically scanned in a direction perpendicular to itself, the sample stage on which the sample 41 is placed is continuously moved in a direction parallel to the band-shaped beam.
[0032]
Secondary electrons emitted from a plurality of points on the irradiated sample 41 travel along the secondary electron principal ray trajectory 42 and are attracted by the electric field of the objective lens 40 and are finely focused. The secondary electrons are deflected by the E × B electromagnetic deflector 37 and the E × B electrostatic deflector 38, separated from the primary electron beam, and incident on the secondary optical system. Secondary electrons that have passed through the magnifying lenses 43 and 44 are each multiplied by a multi-channel plate (MCP) 45, and are absorbed by a multi-anode 46 provided near the back surface. Is converted to The electric signal is sent to the image forming circuit 48 via the multi-amplifier and multi-A / D converter 47.
[0033]
Next, an example of an embodiment of a semiconductor device manufacturing method according to the present invention will be described.
[0034]
FIG. 4 is a flowchart showing an example of a semiconductor device manufacturing method according to the present invention. The manufacturing method of this example includes the following main steps.
(1) Wafer manufacturing process for manufacturing a wafer (or wafer preparation process for preparing a wafer) 400
(2) Mask manufacturing process (or mask preparation process for preparing a mask) 401 for manufacturing a mask used for exposure 401
(3) Wafer processing step 402 for performing necessary processing on the wafer
(4) Chip assembly process 403 for cutting chips formed on the wafer one by one and making them operable
(5) Chip inspection process 404 for inspecting the completed chip
Each process further includes several sub-processes.
[0035]
Among these main processes, the main process that has a decisive influence on the performance of semiconductor devices is the wafer processing process. In this process, designed circuit patterns are sequentially stacked on a wafer to form a large number of chips that operate as memories and MPUs. This wafer processing step includes the following steps.
(1) A thin film forming process for forming a dielectric thin film to be an insulating layer, a wiring portion, or a metal thin film for forming an electrode portion (using CVD, sputtering, etc.)
(2) Oxidation process for oxidizing the thin film layer and the wafer substrate (3) Lithography process for forming a resist pattern using a mask (reticle) for selectively processing the thin film layer and the wafer substrate, etc. (4) Resist Etching process that processes thin film layers and substrates according to patterns (eg, using dry etching technology)
(5) Ion / impurity implantation diffusion process (6) Resist stripping process (7) Inspection process for inspecting further processed wafers The wafer processing process is repeated as many times as necessary to produce semiconductor devices that operate as designed. To do.
[0036]
FIG. 5 is a flowchart showing a lithography process that forms the core of the wafer processing process of FIG. This lithography process includes the following steps.
(1) Resist coating process 500 for coating a resist on a wafer on which a circuit pattern has been formed in the preceding process.
(2) Exposure step 501 for exposing the resist
(3) Development step 502 of developing the exposed resist to obtain a resist pattern
(4) Annealing step 503 for stabilizing the developed resist pattern
The above semiconductor device manufacturing process, wafer processing process, and lithography process are well known and will not require further explanation.
[0037]
When the defect inspection method and the defect inspection apparatus according to the present invention are used in the inspection process of (7) above, even a semiconductor device having a fine pattern can be inspected with high throughput, so that 100% inspection can be performed and the yield of products can be improved. It is possible to prevent shipment of defective products.
[0038]
【The invention's effect】
If the pattern evaluation method of the present invention is performed using an electron beam apparatus using a multi-beam, the evaluation throughput can be increased, so that a high throughput can be evaluated.
[Brief description of the drawings]
FIG. 1 is a schematic plan view of an apparatus used in a pattern evaluation method of the present invention.
FIGS. 2A and 2B are application time charts of a voltage for a decelerating electric field applied to the electrostatic chuck and the wafer, wherein FIG. 2A is a diagram when unloading the wafer, and FIG. 2B is a diagram when loading the wafer;
FIG. 3 is a schematic diagram of an electron optical system of an electron beam apparatus used in the evaluation method of the present invention.
FIG. 4 is a flowchart of a device manufacturing process.
FIG. 5 is a flowchart of a lithography process.
[Explanation of main part codes]
1: Sample chamber 2, 3: Preliminary chamber 4: Stage (sample stage)
5: Wafer (sample)
6: Robot 7: Load arm (transfer arm)
8: Gate valve 9: Gate valve 10: Electrostatic chuck 11, 12: Control power supply 13: Gate valve 21: Line 22 showing a time chart for returning the deceleration electric field voltage to 0 at the time of wafer release: Electrostatic chuck voltage at the time of wafer release Line 23 showing time chart for returning to 0: Line 24 showing time chart for applying deceleration electric field voltage at the time of wafer adsorption: Line 31 showing time chart for applying electrostatic chuck voltage at the time of wafer adsorption: Electron gun 32: Condenser lens 33 : Multi-aperture plate 34: Reduction lens 35: First scanning electrostatic deflector 36: E × B pre-deflector 37: E × B electromagnetic deflector 38: E × B electrostatic deflector 39: Second 2 scanning electrostatic deflector 40: objective lens 41: sample 42: secondary electron principal ray trajectory 43, 44: magnifying lens 45: MCP
46: multi-anode 47: multi-amplifier and multi-A / D converter 48: image forming circuit 49: deflector 50: deflector 51: NA aperture

Claims (7)

A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber for pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading the sample, a gate valve for partitioning the sample chamber and the spare chamber, and a spare chamber for transporting the sample In a device having a transport arm, an electrostatic chuck provided in the sample chamber for fixing the sample, and a negative voltage power source for applying to the sample, the gate valve is opened, and the sample is preliminarily prepared using the transport arm. Taking it out of the chamber and placing it on the electrostatic chuck in the sample chamber through the gate valve;
b. In a state where the electrode of the electrostatic chuck is grounded or a predetermined voltage is applied, applying a negative voltage to the sample and fixing it to the electrostatic chuck;
c. After the sample is fixed to the electrostatic chuck, the step of pulling the transfer arm from the sample chamber through the gate valve to the preliminary chamber side;
d. Closing the gate valve;
e. Irradiating the sample with an electron beam after vibration generated when the gate valve is closed is sufficiently small, and starting a pattern evaluation;
From made, b step and prior child from step d cities,
The electron beam emitted from a single electron beam emission region of a single electron gun is separated by a plurality of apertures, and a reduced image of the plurality of apertures is irradiated onto the sample surface, and the plurality of separated electron beams The pattern is evaluated by continuously moving the sample stage along the stripe while scanning the sample in the uniaxial direction, and the image intervals when the reduced image of the aperture is projected onto the longitudinal axis of the stripe are all equal. The pattern evaluation method characterized by being made to . A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber for pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading the sample, a gate valve for partitioning the sample chamber and the spare chamber, and a spare chamber for transporting the sample In a device having a transport arm, an electrostatic chuck provided in the sample chamber for fixing the sample, and a negative voltage power source for applying to the sample, the gate valve is opened, and the sample is preliminarily prepared using the transport arm. Taking it out of the chamber and placing it on the electrostatic chuck in the sample chamber through the gate valve;
b. In a state where the electrode of the electrostatic chuck is grounded or a predetermined voltage is applied, applying a negative voltage to the sample and fixing it to the electrostatic chuck;
c. After the sample is fixed to the electrostatic chuck, the step of pulling the transfer arm from the sample chamber through the gate valve to the preliminary chamber side;
d. Closing the gate valve;
e. Irradiating the sample with an electron beam after vibration generated when the gate valve is closed is sufficiently small, and starting a pattern evaluation;
And the step b precedes the step d .
The electron beam is emitted from a single electron beam emission region of a single electron gun, and then shaped into a belt-like beam at a linear opening. The belt-like beam is imaged on a sample, and the belt-like beam is formed. A pattern evaluation method characterized by performing pattern evaluation while electrically scanning a beam in a direction perpendicular to itself while continuously moving a sample stage in a direction parallel to a strip-shaped beam . A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber for pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading the sample, a gate valve for partitioning the sample chamber and the spare chamber, and a spare chamber for transporting the sample In a device having a transport arm, an electrostatic chuck provided on a stage in the sample chamber for fixing the sample, and a negative voltage power source for applying the sample to the sample, a static voltage is applied to the sample by applying a negative voltage to the sample. Irradiating a sample fixed on the electric chuck with an electron beam, detecting secondary electrons and evaluating a pattern;
b. After the evaluation of the sample is completed, a step of deflecting the electron beam with a deflector and blanking so as not to come to the sample surface;
c. Moving the stage to a position to unload the sample;
d. Cutting off the negative voltage applied to the sample;
e. Opening the gate valve, placing the transfer arm from the preliminary chamber into the sample chamber, and removing the sample from the sample chamber;
f. Next, removing the sample to be evaluated from the preliminary chamber and placing it on the electrostatic chuck in the sample chamber;
I have a,
The electron beam emitted from a single electron beam emission region of a single electron gun is separated by a plurality of apertures, and a reduced image of the plurality of apertures is irradiated onto the sample surface, and the plurality of separated electron beams The pattern is evaluated by continuously moving the sample stage along the stripe while scanning the sample in the uniaxial direction, and the image intervals when the reduced image of the aperture is projected onto the longitudinal axis of the stripe are all equal. The pattern evaluation method characterized by being made to . A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber for pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading the sample, a gate valve for partitioning the sample chamber and the spare chamber, and a spare chamber for transporting the sample In a device having a transport arm, an electrostatic chuck provided on a stage in the sample chamber for fixing the sample, and a negative voltage power source for applying the sample to the sample, a static voltage is applied to the sample by applying a negative voltage to the sample. Irradiating a sample fixed on the electric chuck with an electron beam, detecting secondary electrons and evaluating a pattern;
b. After the evaluation of the sample is completed, a step of deflecting the electron beam with a deflector and blanking so as not to come to the sample surface;
c. Moving the stage to a position to unload the sample;
d. Cutting off the negative voltage applied to the sample;
e. Opening the gate valve, placing the transfer arm from the preliminary chamber into the sample chamber, and removing the sample from the sample chamber;
f. Next, removing the sample to be evaluated from the preliminary chamber and placing it on the electrostatic chuck in the sample chamber;
I have a,
The electron beam is emitted from a single electron beam emission region of a single electron gun, and then shaped into a belt-like beam at a linear opening. The belt-like beam is imaged on a sample, and the belt-like beam is formed. A pattern evaluation method characterized by performing pattern evaluation while electrically scanning a beam in a direction perpendicular to itself while continuously moving a sample stage in a direction parallel to a strip-shaped beam . A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber that performs pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading a sample, a first gate valve that partitions the sample chamber and the spare chamber, and a spare chamber and an atmospheric chamber are partitioned. In an apparatus having a second gate valve and a transfer arm provided in a preliminary chamber for transferring a sample, the sample in the sample chamber is irradiated with an electron beam, and secondary electrons are detected to perform pattern evaluation. Steps,
b. A step of temporarily stopping the movement of the stage after the evaluation of the stripe under pattern evaluation is completed;
c. Bringing the preparatory chamber to atmospheric pressure before removing the evaluated sample into the atmospheric chamber;
d. Opening the second gate valve and taking the evaluated sample into the atmospheric chamber;
e. Next, carry the sample to be evaluated into the preliminary chamber;
f. Closing the second gate valve and evacuating the reserve chamber;
g. A step of confirming that the degree of vacuum in the preliminary chamber is substantially constant;
h. Starting the evaluation from the stripe to be evaluated next for the sample under evaluation;
I have a,
The electron beam emitted from a single electron beam emission region of a single electron gun is separated by a plurality of apertures, and a reduced image of the plurality of apertures is irradiated onto the sample surface, and the plurality of separated electron beams The pattern is evaluated by continuously moving the sample stage along the stripe while scanning the sample in the uniaxial direction, and the image intervals when the reduced image of the aperture is projected onto the longitudinal axis of the stripe are all equal. The pattern evaluation method characterized by being made to . A method for pattern evaluation of a sample such as a wafer using an electron beam,
a. A sample chamber that performs pattern evaluation by irradiating an electron beam, a spare chamber for loading and unloading a sample, a first gate valve that partitions the sample chamber and the spare chamber, and a spare chamber and an atmospheric chamber are partitioned. In an apparatus having a second gate valve and a transfer arm provided in a preliminary chamber for transferring a sample, the sample in the sample chamber is irradiated with an electron beam, and secondary electrons are detected to perform pattern evaluation. Steps,
b. A step of temporarily stopping the movement of the stage after the evaluation of the stripe under pattern evaluation is completed;
c. Bringing the preparatory chamber to atmospheric pressure before removing the evaluated sample into the atmospheric chamber;
d. Opening the second gate valve and taking the evaluated sample into the atmospheric chamber;
e. Next, carry the sample to be evaluated into the preliminary chamber;
f. Closing the second gate valve and evacuating the reserve chamber;
g. A step of confirming that the degree of vacuum in the preliminary chamber is substantially constant;
h. Starting the evaluation from the stripe to be evaluated next for the sample under evaluation;
I have a,
The electron beam is emitted from a single electron beam emission region of a single electron gun, and then shaped into a belt-like beam at a linear opening. The belt-like beam is imaged on a sample, and the belt-like beam is formed. A pattern evaluation method characterized by performing pattern evaluation while electrically scanning a beam in a direction perpendicular to itself while continuously moving a sample stage in a direction parallel to a strip-shaped beam . Device manufacturing method characterized by using the evaluation method described in any one of claims 1 to 6.

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