JP2016189326A - Test device and electron microscope including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a test device capable of securely heating a deformed portion of a sample at a set temperature to observe and analyze and an electron microscope including the same.SOLUTION: A test device 10 comprises: a sample room 1 having a widow 11 through which a laser beam A can transmit; a heating mechanism 2 for heating a sample 200 by irradiating a surface 200a of the sample 200 disposed inside the sample room 1 with the laser beam A through the window 11 from outside of the sample room 1; and a processing mechanism 3 disposed inside the sample room 1, for processing the sample 200. The heating mechanism 2 includes: a laser oscillator 21 for oscillating the laser beam A; and a condensing and scanning part 22 for condensing the laser beam A, capable of scanning on a surface of the sample 200.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a test apparatus and an electron microscope including the same, and more particularly to a test apparatus suitable for deforming a sample while being heated to a predetermined temperature, and an electron microscope including the test apparatus.

  In the development of general materials such as metals, ceramics, semiconductors, and other inorganic materials or organic materials, it is very important to microscopically observe the behavior of the microstructure in these materials during the thermomechanical process. . In the manufacturing process of steel, the crystal structure is controlled by performing a heat treatment to obtain an appropriate structure form for expressing the performance of the steel. Therefore, in order to further optimize the crystal structure in the steel and obtain a high-performance steel material, the recovery and recrystallization behavior of the steel crystal structure in the medium to high temperature range of 500 to 1200 ° C., which is the temperature range of the thermomechanical processing. It is necessary to grasp.

  Up to now, an apparatus having a mechanism capable of processing and heating an observation sample in an apparatus capable of microscopic observation such as a scanning electron microscope has been developed.

  For example, Patent Document 1 includes a pair of holding portions that hold both end portions of a sample, and a drive mechanism that drives the holding portions in directions away from each other to apply a tensile force to the sample, and includes a deformation region of the sample. There is disclosed a sample stage including a non-contact type main heater located in a non-deformation region and a contact type sub-heater located in a non-deformation region.

  In Non-Patent Document 1, a technique in which a metal sample in a sample chamber of a scanning electron microscope is irradiated with a semiconductor infrared laser, heated to 1000 ° C., and in situ observation of crystal transformation by EBSD (Electron Back Scattering Diffraction) is performed. Have been reported.

JP 2009-032598 A

DM.Kirch, A.Ziemons, I.Lischewski, D.A.Molodov and G.Gottstein, A Novel Laser Powered Heating Stage for In-Situ Investigation in a SEM, Material Science Forum, 558-559, 2007, pp909-914.

  In the sample stage disclosed in Patent Document 1, the non-contact type main heater is installed immediately below the deformed portion, and the contact type heater is installed in the sample portion where the sample does not substantially deform, thereby improving the efficiency of the sample. It is proposed to heat up automatically. However, in order to keep the temperature of the sample deformation part constant while appropriately controlling a plurality of heat sources, the temperature control becomes very complicated, and it is difficult to accurately maintain the deformation part at a predetermined temperature.

  Further, in the heating by a non-contact heater, even if the capacity of the heater is increased, the sample heating efficiency by radiation has a limit, and in particular, the heating up to 1200 ° C. intended by the present invention is difficult. Furthermore, in Patent Document 1, the heating element is covered with a ceramic such as alumina or silicon nitride so that the components of the heater are not evaporated during heating and the evaporated component does not contaminate the sample surface. However, the ceramic components are not completely evaporated in the vacuum vessel, and contamination must be taken into consideration especially when heated to a high temperature up to 1200 ° C.

  Non-Patent Document 1 discloses a method of heating a sample to 1000 ° C. with a laser. However, although heating with a high-intensity laser is local and there is no problem in static observation, if the observation site may move or expand due to tensile processing of the sample, The entire observation site cannot be maintained at a predetermined high temperature. In reproducing and observing the behavior in an actual process such as hot rolling, a proper observation cannot be made unless the entire region to be deformed is at a predetermined temperature.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a test apparatus capable of reliably heating a deformed portion of a sample to a set temperature and observing / analyzing it, and an electron microscope equipped with the test apparatus. In particular, the present invention provides a test apparatus capable of applying stress to a sample in a state where an inorganic material such as a metal, ceramics, or semiconductor, which is an observation sample, is heated to 500 to 1200 ° C., and an electron microscope equipped with the test apparatus. Objective.

  The present invention has been made in order to solve the above-described problems, and provides a gist of the following test apparatus and an electron microscope including the same.

(1) a sample chamber having a window through which laser light can pass;
A heating mechanism that heats the sample by irradiating the surface of the sample disposed inside the sample chamber through the window from the outside of the sample chamber;
A processing mechanism disposed inside the sample chamber and processing the sample,
The heating mechanism includes a laser oscillator that oscillates the laser light, and a condensing scanning unit that condenses the laser light and can scan the surface of the sample.

(2) The condensing scanning unit includes a galvano scanner arranged outside the sample chamber and a lens arranged inside the sample chamber,
The test apparatus according to (1), wherein the laser beam is scanned on the sample surface from the laser oscillator through the galvano scanner and the lens in order.

  (3) The test apparatus according to (2), wherein the lens is an fθ lens.

  (4) The condensing scanning unit further includes a mirror disposed inside the sample chamber and between the galvano scanner and the lens on the path of the laser light. The test apparatus according to (3).

  (5) The heating mechanism according to any one of (1) to (4), further including an irradiation area limiting unit that is disposed inside the sample chamber and limits an area irradiated with the laser beam. Testing equipment.

  (6) The processing mechanism includes a first holding unit that holds one end of the sample and a second holding unit that holds the other end of the sample, and the second holding unit without moving the first holding unit. The test apparatus according to any one of (1) to (5), wherein the sample is processed by moving a portion in a predetermined direction.

(7) The processing mechanism is:
A driving device for generating power;
A transmission member extending in the predetermined direction and transmitting power generated by the driving device to the second holding portion as a force in the predetermined direction;
The sample includes a first fixing unit fixed to the first holding unit, a second fixing unit fixed to the second holding unit, and the first fixing unit and the second fixing extending in the predetermined direction. A plate-like connecting portion including an irradiation region that is connected to the portion and irradiated with the laser beam,
When the transmission member and the connection portion are viewed from a direction perpendicular to the surface of the flat plate-like connection portion, a straight line that passes through the central axis of the transmission member and extends in the predetermined direction is the central axis of the connection portion. The test apparatus according to (6), which matches.

(8) The processing mechanism is:
A main body that supports the first holding part and the transmission member;
The first holding part is fixed to the main body part,
The transmission member is a rotating member having a male screw, and is supported by the main body so as to be rotatable in a state in which movement in the predetermined direction is restricted,
The second holding part has a female screw in which the male screw is rotatably engaged,
The main body has at least one guide portion that extends in the predetermined direction and regulates movement of the second holding portion in a direction inclined with respect to the predetermined direction in a state where the second holding portion is movable in the predetermined direction. And
The driving device rotationally drives the rotating member;
The test apparatus according to (7), wherein the second holding unit moves in the predetermined direction when the driving device rotates the rotating member.

(9) The main body has two guide parts,
The two guide portions are arranged so as to be plane symmetric with respect to a plane parallel to a direction perpendicular to the surface of the flat connecting portion and passing through the central axis of the transmission member. ) Test apparatus.

(10) The processing mechanism includes a sensor that detects information regarding a displacement amount of the sample,
The said condensing scanning part is a test apparatus in any one of said (1) to (9) which adjusts the scanning range of the said laser beam according to the said displacement amount.

  (11) The test apparatus according to (10), wherein the sensor includes a load measuring unit that measures a load applied to the sample and a displacement measuring unit that measures a displacement amount of the sample.

  (12) An electron microscope comprising the test apparatus according to any one of (1) to (11) above, and irradiating an electron beam on the back surface of the sample.

  According to the test apparatus of the present invention, it is possible to heat a sample surface of an inorganic material such as metal, ceramics, or semiconductor to a predetermined temperature by irradiating the focused laser beam, and to apply stress in that state. It becomes. Further, laser light can be scanned in an arbitrary region on the surface of the sample. For this reason, even if the observation site is displaced by processing, the observation site can be reliably held at a predetermined temperature. In addition, since no heater is used, contamination of the sample and the sample chamber due to the evaporation element derived from the heater can be avoided.

It is the figure which showed typically an example of the scanning electron microscope provided with the test apparatus which concerns on one Embodiment and other embodiment of this invention. It is the figure which showed typically the testing apparatus which concerns on one Embodiment of this invention. It is the schematic diagram which looked at the processing mechanism which concerns on one Embodiment of this invention from the irradiation direction of the laser beam. It is the schematic diagram which looked at the processing mechanism which concerns on one Embodiment of this invention, and the irradiation area limiting means which a heating mechanism has from the irradiation direction of the laser beam. It is the schematic diagram which looked at the processing mechanism which concerns on other embodiment of this invention from the irradiation direction of the laser beam. It is the schematic diagram which looked at the processing mechanism which concerns on other embodiment of this invention from the irradiation direction of the laser beam. It is the schematic diagram which looked at the processing mechanism which concerns on other embodiment of this invention from the irradiation direction of the laser beam. It is the schematic diagram which looked at the processing mechanism which concerns on other embodiment of this invention from the irradiation direction of the laser beam. It is the schematic diagram which looked at the processing mechanism which concerns on other embodiment of this invention from the irradiation direction of the laser beam. It is the sectional view on the aa line in FIG.

  An example of an embodiment of the present invention will be described. In the following description, an example is given in which a steel material is used as a sample, tensile processing is performed in a heated state, and the crystal structure is observed with a scanning electron microscope (SEM).

  FIG. 1 is a diagram schematically illustrating an example of an SEM 1000 including a test apparatus 10 and an SEM main body 100. The test apparatus 10 according to an embodiment of the present invention irradiates the surface 200 a of the sample 200 with the laser beam A through the window 11 from the outside of the sample chamber 1 and the sample chamber 1 through which the laser beam A can pass. And a heating mechanism 2 for heating, a processing mechanism 3 for processing the sample 200, and a control device 500 such as a computer. While the sample 200 is heated by the heating mechanism 2 and the sample 200 is deformed by the processing mechanism 3, the back surface 200 b of the sample 200 is irradiated with the electron beam bundle B by the SEM main body 100 and emitted from the sample 200. By detecting secondary electrons and the like, the deformed portion is observed with a microscope.

  There is no restriction | limiting in particular about the structure of the SEM main-body part 100, What is necessary is just to use the thing of a general structure. As shown in FIG. 1, for example, an electron gun 110 that extracts electrons from an electron source and emits an electron beam B while accelerating, a condenser lens 120 that focuses the accelerated electron beam B, and a focused electron beam B Can be configured to include an objective lens 130 for converging the light beam to a minute region on the sample 200, a pole piece 140 including the objective lens 130, and a deflection coil 150 for scanning the electron beam bundle B on the sample 200. Further, secondary electrons emitted from the sample 200 are detected by the secondary electron detector 160.

  Each configuration of the test apparatus according to one embodiment and other embodiments of the present invention will be described in detail below.

1. Sample Chamber The test apparatus 10 includes a sample chamber 1. It is desirable that the sample chamber 1 has a function of making the inside vacuum. When the sample 200 is analyzed using the SEM 1000, the vacuum sample chamber of the SEM 1000 can be used as the sample chamber 1 as it is, as shown in FIG. The sample chamber 1 has a window 11 through which the laser beam A can pass. Although there is no restriction | limiting in particular about the material of the window 11, For example, quartz glass or sapphire glass etc. can be used.

2. Heating Mechanism The test apparatus 10 includes a heating mechanism 2. As shown in FIGS. 1 and 2, the heating mechanism 2 has a laser oscillator 21 that oscillates the laser light A, and a condensing scanning unit 22 that condenses the laser light A and can scan on the surface of the sample 200. .

  As described above, when a heater is used for heating the sample, there is a possibility that the sample and the sample chamber may be contaminated by the evaporating element derived from the heater. However, in one embodiment and other embodiments of the present invention, the sample is heated by the laser beam, so that the evaporation element derived from a heating source such as a heater does not cause contamination in the sample and the sample chamber. Although there is no restriction | limiting in particular about the kind of laser oscillator 21, For example, a semiconductor laser oscillator or a YAG laser oscillator is mentioned. Since it aims at steady heating, it is desirable to use a continuous oscillation type rather than a pulse oscillation.

  Further, FIG. 3 shows a view of the sample 200 as viewed from the irradiation direction of the laser light A (hereinafter also referred to as “A direction”). The condensing scanning unit 22 condenses the laser light A and scans the irradiation area 240 on the sample surface with the laser light A. The scanning of the laser beam A by the condensing scanning unit 22 is controlled by a control device 500 such as a computer, and the entire region to be heated is scanned with the laser beam A evenly, so that the region to be heated can be uniformly heated. For example, the condensing scanning unit 22 may include a galvano scanner 22a and a lens 22b. With this configuration, it is possible to scan the laser light A on the sample surface from the laser oscillator 21 through the galvano scanner 22a and the lens 22b in this order.

  The laser oscillator 21 and the galvano scanner 22 a are arranged outside the sample chamber 1, and the lens 22 b is arranged inside the sample chamber 1. The laser oscillator 21 and the galvano scanner 22 a are connected to the control device 500.

As shown in FIGS. 1 and 2, the galvano scanner 22a has movable galvanometer mirrors 22a ₁ and 22a ₂ inside, and has a mechanism for changing the irradiation position of the laser beam A by driving them. is there. Since the galvano scanner 22a is arranged outside the sample chamber 1, even when the galvanometer mirrors 22a ₁ and 22a ₂ are driven when the condensing scanning unit 22 includes the galvano scanner 22a, the sample is generated by the vibration generated thereby. 200 or the sample chamber 1 can be prevented from shaking, and high-precision SEM observation can be performed.

Further, it is preferable to use an fθ lens as the lens 22b. If configured to irradiate the laser beam A to the sample surface via the galvano scanner 22a and fθ lens in order, the angle of the galvanomirror 22a ₁ and galvanomirror 22a ₂ having galvano scanner 22a when the conformally rotated by fθ lens Laser light can be scanned at a constant speed on the sample surface. The laser beam A is condensed by the fθ lens, and the laser spot diameter is set to 0.5 to 2 mm, for example.

  As shown in FIG. 2, the condensing scanning unit 22 further includes a mirror 22 c disposed between the galvano scanner 22 a and the lens 22 b on the path of the laser light A inside the sample chamber 1. May be. With such a configuration, the optical path can be freely bent in the sample chamber, so that space can be saved.

  As shown in FIGS. 2 and 4, the heating mechanism 2 may further include an irradiation region limiting unit 23 disposed inside the sample chamber 1. As the irradiation region limiting means 23, for example, a plate having a slit 23a as shown in FIG. 4 and having a plate shape made of a material that does not allow laser light to pass therethrough can be used. Since the region irradiated with the laser beam A is limited to only the slit 23a, it is possible to reliably prevent the laser beam A from being accidentally irradiated to other parts of the sample chamber such as the SEM main body. Is possible. The irradiation area limiting means 23 is preferably arranged in a non-contact state with the sample 200 so as not to disturb the deformation and heating of the sample 200.

  When performing deformation processing while the sample 200 is heated and performing SEM observation, it is preferable that the observation site is reliably maintained at a predetermined temperature even if the observation site moves. The sample temperature may be measured using a thermocouple assembled to the sample 200 or a non-contact thermometer such as a pyrometer. The sample temperature can be controlled by manual control or PID control. In the case of manual control, the laser light intensity is manually adjusted while looking at the temperature indicated by the thermometer. In the case of PID control, temperature measurement and laser intensity adjustment are automatically performed using a control computer.

3. Processing Mechanism The test apparatus 10 includes a processing mechanism 3 disposed inside the sample chamber 1. The configuration of the processing mechanism 3 is not particularly limited as long as the sample 200 can be deformed. For example, as shown in FIG. 3, the sample mechanism 200 has a predetermined direction (X in FIG. 3). Direction)).

  In the configuration shown in FIG. 3, the processing mechanism 3 includes a first holding unit 31 that holds one end of the sample 200 and a second holding unit 32 that holds the other end of the sample 200. For example, the first holding part 31 and the second holding part 32 are metal blocks, provided with recesses 31 a and 32 a for fitting both ends of the sample 200, and fixing for fixing both ends of the sample 200. It can be set as the structure provided with the pins 31b and 32b.

  The sample 200 includes a first fixing unit 210 that is fixed to the first holding unit 31 and a second fixing unit 220 that is fixed to the second holding unit 32. In addition, the sample 200 includes a connection portion 230 that extends in the X direction, connects the first fixing portion 210 and the second fixing portion 220, and includes an irradiation region 240 irradiated with the laser light A. In the configuration shown in FIG. 3, a dumbbell shape is formed such that the cross-sectional areas of the first fixing portion 210 and the second fixing portion 220 are larger than those of the connection portion 230.

  When performing a tensile process on the sample 200, the first holding unit 31 and the second holding unit 32 may be driven in opposite directions, but in the embodiment of the present invention, the first holding unit 31 is fixed. Therefore, it is desirable that the sample 200 be processed by moving the second holding part 32 in the X direction without moving it. By doing in this way, since the moving direction of the deformation | transformation part at the time of a tension process is restrict | limited, it becomes easy to follow and ensure an observation visual field.

  As shown in FIG. 5, the machining mechanism 3 according to an embodiment of the present invention may further include a drive device 33 that generates power and a transmission member 34 that transmits the power to the second holding portion 32. Good. As the driving device 33, an actuator such as a motor or a piezoelectric element can be used. The transmission member 34 extends in the X direction and transmits the power generated by the drive device 33 to the second holding unit 32 as a force in the X direction. Then, the sample 200 is processed by moving the second holding unit 32 in the X direction. The drive device 33 is connected to the control device 500 and is controlled by the control device 500.

In the above configuration, for example, as shown in FIG. 6, when the connection member 230 included in the transmission member 34 and the sample 200 is viewed from the A direction, a straight line X ₁ that passes through the central axis of the transmission member 34 and extends in the X direction. However, if it is greatly displaced from the connecting portion 230, a bending moment of a component in the direction perpendicular to the A direction and the X direction (Y direction in FIG. 6) is generated in the sample 200. Along with that, the observation visual field shifts in the Y direction, which causes a problem that observation becomes difficult.

Configuration Therefore, the connection portion 230 of the transmission member 34 and the sample 200 have when viewed from the direction A, a straight line X ₁ extending through and X-direction central axis of the transmission member 34, which coincides with the central axis of the connection portion 230 It is preferable that With the above configuration, not only can the observation visual field accompanying processing be prevented from shifting in the Y direction, but also the movement of the second holding portion 32 in the X direction becomes smooth. The central axis of the transmission member 34 refers to an axis extending in the direction in which the transmission member 34 transmits power. When the connection part 230 of the sample 200 is flat, the A direction is a direction perpendicular to the surface of the flat connection part 230.

  The processing mechanism 3 according to another embodiment of the present invention may further include a main body portion 35 that supports the first holding portion 31a and the transmission member 34, as shown in FIGS. The first holding part 31 is fixed to the main body part 35 and may be integrated as shown in FIG. The transmission member 34 is a rotation member 34 ′ having a male screw 34 a and is supported by the main body 35 so as to be rotatable in a state where movement in the X direction is restricted. The mechanism that restricts the movement of the rotating member 34 ′ in the X direction is not particularly limited. For example, as shown in FIGS. 7 to 9, the movement in the X direction is restricted by providing restrictors 34 b and 34 c. In this state, the rotation member 34 ′ can be rotatably supported by the main body portion 35.

  In the above configuration, in order to prevent the twisting force from being applied to the sample 200, the main body portion 35 preferably has at least one guide portion 35a. The guide part 35a extends in the X direction and restricts the movement in the direction inclined with respect to the X direction while the second holding part 32 is movable in the X direction. As an aspect for realizing the above mechanism, for example, as shown in FIGS. 7 and 8, the main body portion 35 has a columnar guide portion 35 a extending in the X direction, and the second holding portion 32 is a guide. It can be set as the structure which has the hole 32d by which the part 35a is penetrated.

  And the 2nd holding | maintenance part 32 has the internal thread 32c by which the external thread 34a which rotating member 34 'has was screwed together freely, and the 2nd holding | maintenance part 32 is rotated when the drive device 33 rotates rotating member 34'. Moves in the X direction. As shown in FIGS. 8 and 9, the female screw 32 c formed in the second holding portion 32 may be formed on the inner peripheral surface of the through hole. If it is said structure, it will become possible to enlarge the movable range of the 2nd holding | maintenance part 32. FIG. The drive device 33 only needs to have a configuration capable of rotationally driving the rotation member 34 ′. For example, as illustrated in FIGS. 8 and 9, the drive device 33 may include a motor 33 a and a gear box 33 b.

Even in the configuration according to the above-described embodiment, when the connecting member 230 included in the rotating member 34 ′ and the sample 200 is viewed from the A direction, it passes through the central axis of the rotating member 34 ′ and extends in the X direction. As described above, it is preferable that the straight line X ₁ has a configuration that coincides with the central axis of the connecting portion 230.

  Furthermore, the main body part 35 may have two guide parts 35a and 35b. As an aspect for realizing the above mechanism, for example, as shown in FIG. 9, the main body portion 35 has two columnar guide portions 35 a and 35 b extending in the X direction, and the second holding portion 32 is The guide portions 35a and 35b may have two holes 32d and 32e.

The two guide portions 35a and 35b are arranged so as to be symmetrical with respect to a plane parallel to the A direction and passing through the central axis of the transmission member 34. 10 is a cross-sectional view taken along line aa in FIG. In FIG. 10, the holes 32d and 32e through which the guide portions 35a and 35b are inserted are preferably formed at positions 32d ₁ and 32e ₁ that are point-symmetrical about the central axis of the rotating member 34 ′. , 32d ₂ , 32e ₂ or 32d ₃ , 32e ₃ .

  By having the guide portions 35a and 35b arranged in this way, the movable direction of the second holding portion 32 is limited to the X direction, and the displacement of the observation visual field in the Y direction due to processing can be prevented more reliably. It becomes possible. Further, it is possible to reduce friction generated between the second holding portion 32 and the rotating member 34 '.

  Moreover, as shown in FIG. 9, the main body may further include tension springs 35c and 35d provided so as to cover the guides 35a and 35b. By having the tension springs 35c and 35d, it is possible to reduce the burden on the rotating member 34 'when the second holding portion 32 is moved in the X direction. In the configuration shown in FIG. 9, a tension spring is provided between the main body portion 35 and the second holding portion 32 on the assumption that the sample 200 is subjected to a tensile process, but the sample 200 is subjected to a compression process. If desired, a tension spring may be provided between the first holding part 31 and the second holding part 32.

  The processing mechanism 3 may include a sensor 36 for detecting information related to the processing amount that the sample 200 has received by deformation processing. Information on the processing amount includes a load applied to the sample 200 and a displacement amount of the sample 200. For example, the sensor 36 may include a load measuring unit 36 a that measures a load applied to the sample 200 and a displacement measuring unit 36 b that measures the amount of displacement of the sample 200. By incorporating the load measuring unit 36a into the first sample holding unit 31, the stress applied to the sample can be recorded as a load.

  Further, the displacement measuring unit 36 b is attached to the first holding unit 31 and the second holding unit 32, and the amount of movement of the second holding unit 32 relative to the first holding unit 31 can be measured as the amount of displacement of the sample 200. . The measured displacement amount is input to the control device 500. The control device 500 controls the galvano scanner 22a in accordance with the measured displacement amount, and adjusts the scanning range of the laser light A so that the laser light A is irradiated on the entire observation region expanded by the tensile process. Thus, even if the observation site is expanded by tensile processing, the entire observation site can be reliably maintained at a predetermined temperature.

4). Test Method An example of a test method using the test apparatus 10 will be described. First, a sample 200 is prepared. In this example, a stainless steel material of SUS304 was cut into a predetermined shape by electric discharge machining, and then the sample was obtained by mirror polishing the surface. As shown in FIG. 3, the sample 200 has a connection portion 230 having a minimum width in the vicinity of the central portion, and a shape having a first fixing portion 210 and a second fixing portion 220 that increase in width at both ends. The length of the connection part 230 of the sample 200 is approximately 30 mm. When the sample having the above-described shape is pulled, plastic deformation occurs near the center of the sample, and the deformation region can be substantially limited only to the connection portion 230.

  Next, the sample 200 was fixed to the first holding unit 31 and the second holding unit 32 of the processing mechanism 3. When the sample 200 is fixed to the first holding part 31 and the second holding part 32, the first fixing part 210 and the second fixing part 220 of the measurement sample are fitted into the recesses 31a and 32a as shown in FIG. The sample 200 is fixed in such a manner that the shoulders of the first fixing part 210 and the second fixing part 220 are hooked on the fixing pins 31b and 32b, respectively. When the fixing of the sample is completed, a laser beam is scanned on the irradiation region 240 on the surface 200a of the sample 200 using a galvano scanner, and the first 200 fixed to the main body 35 is heated to a predetermined temperature. By moving the second holding unit 32 in the X direction with respect to the holding unit 31, the first holding unit 31 and the second holding unit 32 are separated from each other, and a tensile stress is applied to the sample 200. The sample 200 undergoes tensile deformation due to the tensile stress.

  In this state, the movement of the second holding unit 32 is temporarily stopped, the back surface 200b of the sample 200 is observed with an SEM, and the change in the surface crystal structure is recorded. By performing such a test, for example, it is possible to reproduce the change in the metal structure and the occurrence of defects during hot working and observe the state.

  Alternatively, the sample 200 may be first subjected to tensile stress and subjected to tensile deformation, and then heated, and the state may be observed with an SEM. When such a test is performed, for example, it is possible to reproduce a situation in which a defect in a metal structure caused by cold working is recovered by a subsequent heat treatment.

  Although it is desirable to measure the temperature of the sample 200 using a commercially available pyrometer, when using a thermocouple, the thermocouple is welded to a location that is a little away from the center of the minimum width portion and does not hinder the deformation of the sample. It is desirable.

An example of the specification of the sample device is shown below.
Stroke of drive base (difference between shortest distance and longest distance between sample holders): 5mm
Maximum tensile load: 500 MPa
Tensile speed: 0.5 to 10 μm / s
Heating temperature: room temperature to 1200 ° C at the sample temperature
Heating rate: ~ 100 ° C / s
Laser beam scanning speed: 1000 mm / s
Laser beam scanning range: 3 mm x 30 mm

  As a result of measuring the target temperature of the deformation region of the sample in this embodiment at 900 ° C., it is possible to heat the deformation region of the measurement sample to 900 ° C. using a semiconductor laser light source with a wavelength of 938 nm and an output of 150 W. It was confirmed. Moreover, the image obtained by SEM observation was clear with no surface contamination.

  Moreover, as a result of installing thermocouples at three locations at 5 mm intervals in the part including the deformation region of the sample and measuring the temperature, all measured values are within 900 ± 2 ° C. and are uniformly heated. Was confirmed.

  For comparison, the galvano scanner was not operated, and the temperature was measured at approximately the center point in the direction of the tensile axis of the sample before starting the tension and two points 5 mm apart on both sides in the same manner as described above. Even when the temperature was controlled at 2 ° C., the two points on both sides were lowered by 30 to 40 ° C. and could not be heated uniformly.

1. Sample chamber 2. 2. Processing mechanism Heating mechanism 10. Test apparatus 11. Windows 21. Laser oscillator 22. Condensing scanning unit 22a. Galvano scanners 22a ₁ , 22a ₂ . Galvano mirror 22b. Lens 22c. Mirror 23. Irradiation area limiting means 23a. Slit 31. First holding unit 32. 2nd holding | maintenance part 31a, 32a. Recess 31b, 32b. Fixing pin 32c. Female thread 32d, 32e. Hole 33. Drive device 33a. Motor 33b. Gearbox 34. Transmission member 34 '. Rotating member 34a. Male thread 34b, 34c. Regulator 35. Main body 35a, 35b. Guide portions 35c, 35d. Tension spring 36. Sensor 36a. Load measuring section 36b. Displacement measuring unit 100. SEM main body 110. Electron gun 120. Condenser lens 130. Objective lens 140. Pole piece 150. Deflection coil 160. Secondary electron detector 200. Sample 200a. Surface 200b. Back surface 210. First fixing part 220. Second fixing portion 230. Connection unit 240. Irradiation area 500. Control device 1000. SEM

Claims (12)

A sample chamber having a window through which laser light can pass;
A heating mechanism that heats the sample by irradiating the surface of the sample disposed inside the sample chamber through the window from the outside of the sample chamber;
A processing mechanism disposed inside the sample chamber and processing the sample,
The heating mechanism includes a laser oscillator that oscillates the laser light, and a condensing scanning unit that condenses the laser light and can scan the surface of the sample. The condensing scanning unit includes a galvano scanner arranged outside the sample chamber and a lens arranged inside the sample chamber,
The test apparatus according to claim 1, wherein the laser light is scanned on the sample surface from the laser oscillator through the galvano scanner and the lens in order.   The test apparatus according to claim 2, wherein the lens is an fθ lens.   The said condensing scanning part is the inside of the said sample chamber, Comprising: On the path | route of the said laser beam, it further contains the mirror arrange | positioned between the said galvano scanner and the said lens. The test apparatus described.   The test apparatus according to any one of claims 1 to 4, wherein the heating mechanism further includes an irradiation area limiting unit that is disposed inside the sample chamber and limits an area irradiated with the laser light.   The processing mechanism includes a first holding unit that holds one end of the sample and a second holding unit that holds the other end of the sample, and the second holding unit is fixed without moving the first holding unit. The test apparatus according to claim 1, wherein the sample is processed by moving in a direction. The processing mechanism is:
A driving device for generating power;
A transmission member extending in the predetermined direction and transmitting power generated by the driving device to the second holding portion as a force in the predetermined direction;
The sample includes a first fixing unit fixed to the first holding unit, a second fixing unit fixed to the second holding unit, and the first fixing unit and the second fixing extending in the predetermined direction. A plate-like connecting portion including an irradiation region that is connected to the portion and irradiated with the laser beam,
When the transmission member and the connection portion are viewed from a direction perpendicular to the surface of the flat plate-like connection portion, a straight line that passes through the central axis of the transmission member and extends in the predetermined direction is the central axis of the connection portion. The test apparatus according to claim 6, which matches. The processing mechanism is:
A main body that supports the first holding part and the transmission member;
The first holding part is fixed to the main body part,
The transmission member is a rotating member having a male screw, and is supported by the main body so as to be rotatable in a state in which movement in the predetermined direction is restricted,
The second holding part has a female screw in which the male screw is rotatably engaged,
The main body has at least one guide portion that extends in the predetermined direction and regulates movement of the second holding portion in a direction inclined with respect to the predetermined direction in a state where the second holding portion is movable in the predetermined direction. And
The driving device rotationally drives the rotating member;
The test apparatus according to claim 7, wherein the second holding unit moves in the predetermined direction when the driving device rotates the rotating member. The main body has two guide parts,
The two guide portions are arranged so as to be symmetrical with respect to a plane parallel to a direction perpendicular to the surface of the flat connecting portion and passing through the central axis of the transmission member. The test apparatus described in 1. The processing mechanism has a sensor that detects information about the amount of displacement of the sample,
The test apparatus according to claim 1, wherein the condensing scanning unit adjusts a scanning range of the laser light in accordance with the displacement amount.   The test apparatus according to claim 10, wherein the sensor includes a load measurement unit that measures a load applied to the sample and a displacement measurement unit that measures a displacement amount of the sample.   An electron microscope comprising the test apparatus according to claim 1, and irradiating an electron beam on a back surface of the sample.

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