JP4344850B2 - Micro material testing equipment - Google Patents

Description

  The present invention relates to a micromaterial testing apparatus that measures the mechanical properties of a micromaterial, for example, its mechanical characteristics with high accuracy.

  Advances in semiconductor processing technology have led to higher integration and higher performance of electronic devices used in micromachines, etc. In order to improve the reliability of these microdevices, the mechanical characteristics have been increased. It is important to measure and evaluate accurately. In addition, in order to evaluate the mechanical properties of silicon-based micromaterials configured as protective films and functional thin films for these devices, it is necessary to measure the properties of the devices under micro dimensions and apply the data obtained in the design to the design. . However, this silicon-based micromaterial, such as a semiconductor silicon-based thin film or a diamond-like carbon thin film, has an extremely small dimensional configuration, and it is extremely difficult to evaluate its mechanical characteristics with high accuracy.

  Conventionally, a micromaterial testing apparatus that measures the mechanical properties of a micromaterial by a so-called tensile test method has been proposed (see Patent Document 1). FIG. 11 is a schematic perspective view showing a micromaterial testing apparatus 80 according to a conventional example. As shown in the figure, the micromaterial test apparatus 80 has a test piece 81 whose mechanical properties are to be measured fixed, a tensile test mechanism 82 that applies a tensile or compressive load to the test piece 81, and a load. And a scanning probe microscope 83 for measuring a minute strain generated in the test piece 81.

  FIG. 12 is a schematic plan view showing the tensile test mechanism 82. As shown in the figure, the tensile test mechanism 82 includes a chuck portion 84 for holding the test piece 81, and piezoelectric element actuators 85a and 85b for applying a tensile load or a compressive load to the test piece 81 via the chuck portion 84. And a load cell 86 that detects the magnitude of the tensile load applied to the test piece 81. Here, the piezoelectric element actuator 85a is a fine movement actuator that applies ultrafine movement to the chuck portion 84, and the piezoelectric element actuator 85b is a coarse movement actuator that greatly moves the chuck portion 84, depending on the mechanical characteristics of the test piece 81 or the measurement purpose. It is something to use properly. On the other hand, as shown in FIG. 11, the scanning probe microscope 83 is a so-called atomic force microscope, and includes a cantilever 88 having a probe 87 protruding from the tip thereof. The shape of the surface of the test piece 81 is precisely measured by scanning across the surface of the test piece and detecting the atomic force generated between the probe 87 and the test piece 81.

  When measuring the test piece 81, first, the test piece 81 is attached to the chuck portion 84, and the tensile load is applied to the test piece 81 by operating the piezoelectric element actuators 85 a and 85 b to move the chuck portion 84. Here, a fine grid-like line pattern 89 is formed on the surface of the test piece 81, and the line pattern 89 changes when a tensile load is applied to the test piece 81. The change of the line pattern 89 is observed using the scanning probe microscope 83, and thereby the longitudinal strain and the lateral strain generated in the test piece 81 are measured. From the above, the Young's modulus and Poisson's ratio of the test piece 81 can be calculated using the tensile load, the longitudinal strain, and the lateral strain.

JP 2003-207432 A

  However, in the conventional micromaterial testing apparatus 80, the load cell 86 is used to detect the magnitude of the load applied to the test piece 81. The load cell 86 has an electrical resistance of a strain gauge corresponding to the strain. The detection sensitivity is only about 1.0 gram. Here, considering that the minute longitudinal strain and lateral strain of the test piece 81 are measured on the nanometer order by observation using the scanning probe microscope 83, the mechanical characteristics of the test piece 81 can be made more accurate. In order to measure, it is necessary to detect the magnitude of the load applied to the test piece 81 with higher accuracy.

  The present invention has been made in view of such problems, and in a micromaterial testing apparatus that measures the mechanical properties of micromaterials by a tensile test method, the magnitude of a load applied to a test piece can be detected with higher accuracy. Thus, a means is provided that enables the mechanical properties of the test piece to be measured with higher accuracy.

  In order to achieve the above object, the invention according to claim 1 is a load-loading means for applying a tensile or compressive load to the test piece to be measured, and a load for detecting the magnitude of the load applied by the load-loading means. In the micromaterial testing apparatus comprising the detecting means, the load applying means is a pair of block bodies that respectively hold both end portions of the test piece, and the test is performed by separating or approaching the block bodies. A load-loading member that applies a load to the piece, and a support member that immovably supports one of the block bodies, and the load detecting means is a strain generated in the one block body. It is a cantilever mechanism that detects

  According to a second aspect of the present invention, the cantilever mechanism includes a cantilever main body disposed with a tip portion in contact with or close to a load-loading direction edge of the one block body, and one end at the base end of the cantilever main body. Piezoelectric element actuators each having an end attached to the support member, a displacement detection unit that detects the amount of bending of the cantilever body, and a servo that controls the voltage applied to the piezoelectric element actuator so as to cancel the bending of the cantilever body Part.

  According to a third aspect of the present invention, the cantilever mechanism includes a rigid body attached to the one block body, and a cantilever main body arranged with a proximal end fixed to the support member and a distal end in contact with or close to the rigid body. A piezoelectric element actuator having one end attached to the one block body and the other end attached to the rigid body, a displacement detector for detecting the amount of bending of the cantilever body, and the piezoelectric so as to cancel the bending of the cantilever body. And a servo unit that controls a voltage applied to the element actuator.

  According to a fourth aspect of the present invention, the fatigue strength of the test piece is measured by the load applying means repeatedly applying a load to the test piece.

  According to the micromaterial testing apparatus according to the present invention, the load loading means for applying a tensile or compressive load to the test piece to be measured, and the load detection means for detecting the magnitude of the load applied by the load loading means. In the micromaterial testing apparatus comprising: a pair of block bodies that respectively hold both end portions of the test piece; and the test piece by separating or approaching the block bodies. A load-loading member that applies a load; and a support member that immovably supports one of the block bodies, and the load detection unit detects strain generated in the one block body. Because it is a cantilever mechanism, the magnitude of the load applied to the specimen can be detected with high accuracy, and the Young's modulus and Poisson's ratio, which are the mechanical properties of the specimen, can be measured with high accuracy. Door can be.

  Further, according to the micromaterial testing apparatus, the cantilever mechanism includes a cantilever main body arranged with a tip portion in contact with or close to a load-loading direction edge of the one block body, and one end being a base of the cantilever main body. A piezoelectric element actuator having the other end attached to the support member, a displacement detection unit that detects the amount of bending of the cantilever body, and a voltage applied to the piezoelectric element actuator so as to cancel the bending of the cantilever body And a servo unit that controls the movement of the cantilever body by applying a voltage to the piezoelectric element actuator to expand and contract, thereby canceling the bending of the cantilever body. At this time, the amount of deflection of the cantilever body can be converted into a voltage and detected by measuring the voltage required for cancellation as a minute displacement output of the servo section. In this way, the amount of load applied to the test piece is detected with higher accuracy by measuring the amount of deflection of the cantilever body using a piezoelectric element with a very small change amount per applied voltage and high resolution. be able to. Therefore, the mechanical properties of the test piece can be measured with higher accuracy.

  Further, according to the micromaterial testing apparatus, the cantilever mechanism is arranged such that the rigid body attached to the one block body, the base end portion is fixed to the support member, and the distal end portion is in contact with or close to the rigid body. A cantilever body, a piezoelectric element actuator having one end attached to the one block body and the other end attached to the rigid body, a displacement detection unit for detecting a deflection amount of the cantilever body, and canceling the deflection of the cantilever body And a servo unit for controlling the voltage applied to the piezoelectric element actuator, so that the position of the rigid body can be adjusted so as to cancel the bending of the cantilever body by applying a voltage to the piezoelectric element actuator to expand and contract. Is done. At this time, the amount of deflection of the cantilever body can be converted into a voltage and detected by measuring the voltage required for cancellation as a minute displacement output of the servo section. In this way, the amount of load applied to the test piece is detected with higher accuracy by measuring the amount of deflection of the cantilever body using a piezoelectric element with a very small change amount per applied voltage and high resolution. be able to. Therefore, the mechanical properties of the test piece can be measured with higher accuracy.

  Further, according to the present micromaterial testing apparatus, the fatigue strength of the test piece can be measured by the load loading means repeatedly applying a load to the test piece.

  Hereinafter, a micromaterial testing apparatus according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view showing the micromaterial testing apparatus 1. As shown in the figure, the micromaterial testing apparatus 1 includes a sample table 3 on which a test piece 2 to be measured is placed, and a tensile test in which a tensile or compressive load is applied to the test piece 2 on the sample table 3. Means (load loading means) 4, minute load detection means (load detection means) 5 for detecting the magnitude of the load applied by the tensile test means 4, and minute strain generated in the test piece 2 when a load is applied And a scanning probe microscope 6 for measuring.

  2 to 4 are views showing the structure of the tensile test means 4. FIG. 2 is a schematic plan view, FIG. 3 is a schematic longitudinal sectional view showing the AA cross section in FIG. 2, and FIG. It is a schematic longitudinal cross-sectional view which shows a BB cross section. As shown in FIG. 2, the tensile test means 4 includes a pair of block bodies 7 on which the test piece 2 to be measured is fixed and placed on the sample table 3, and a tension against the pair of block bodies 7. Alternatively, a pair of load-loading actuators (load-loading members) 8 that apply a compressive load, a support member 9 that supports one of the pair of block bodies so as not to move, and a movement distance detection that detects the movement distance of the block body 7 The sensor 10 is provided.

  As shown in FIGS. 2 and 3, the block body 7 includes a base block 12 having a substantially T-shaped stepped portion 11 formed in one end portion of a substantially rectangular parallelepiped, and a stepped portion of the base block 12. The T block 13 is placed on the upper surface of the portion 11. In the base block 12, a pair of lateral grooves 14 are formed at both ends in the width direction, and vertical grooves 15 are formed from the end of one lateral groove 14 toward the end of the other lateral groove 14. The lateral grooves 14 are for accommodating the load-loading actuators 8 and are formed so as to be parallel to the long sides of the base block 12. Further, the vertical groove 15 is bent in a reverse U shape toward the center of the base block 12 and is parallel to the short side of the base block 12 from both ends of the bent portion 15a. And a straight portion 15b formed on the surface. On the other hand, the T block 13 has a T-shape whose cross-sectional shape is slightly smaller than the planar shape of the stepped portion 11 of the base block 12, and whose height dimension is substantially equal to the height dimension of the stepped portion 11. It is. As shown in FIG. 3, the T block 13 is placed on the upper surface of the stepped portion 11 with a gap 16 spaced apart from the base block 12. At this time, since the height dimension of the T block 13 is equal to the height dimension of the stepped portion 11, the upper surface of the T block 13 and the upper surface of the base block 12 are substantially flush with each other.

  The test piece 2 is a micro thin film material such as a semiconductor silicon thin film, for example, and as shown in FIG. 2, in this embodiment, a narrow bridge portion at the center of a thin film of 50 μm long × 100 μm wide × 5 μm thick. 17 is formed. The bridge portion 17 is provided with a minute lattice-like line pattern 18. By observing the change of the line pattern 18 with the scanning probe microscope 6, a minute distortion generated in the test piece 2 is observed. It is possible to measure. Although not shown in detail in the figure, instead of the line pattern 18, two marks are provided on the bridge portion 17 at a predetermined interval, and the change in the distance between the marks when a load is applied is measured by a scanning probe. By observing with the microscope 6, it is also possible to measure the minute strain of the test piece 2.

  As shown in FIG. 2, the test piece 2 has one end attached to the base block 12 and the other end attached to the T block 13. In more detail, as shown in FIG. 4, the end portion of the T block 13 is formed with a mounting step portion 19 that is stepped down from the surroundings, and both sides of the base block 12 sandwiching the bent portion 15 a. In addition, mounting step portions 20 and 21 that are stepped down from the periphery are formed. The test piece 2 is arranged in parallel with the lateral groove 14 so as to straddle the bent portion 15a of the vertical groove 15 and the gap 16, and one end thereof is on the upper surface of the attachment step portion 19 and the other end portion is the attachment step. It is mounted on the upper surface of the part 21. At both ends of the test piece 2, hook-shaped pressing members 22 are arranged so as to contact the upper surface of the test piece 2, and each pressing member 22 is fixed by a fixture 23 such as a screw. The base block 12 and the T block 13 are respectively fixed. As a result, by tightening the fixture 23, the test piece 2 is pressed downward and fixed in position by the fixture 23, so that the test piece 2 is not displaced when a load is applied. In this way, the test piece 2 is arranged at the substantially central portion in the thickness direction of the base block 12 and the T block 13, and both end portions thereof are fixed to the base block 12 and the T block 13, respectively.

  Although not shown in detail in the drawing, the load-loading actuator 8 is provided with electrodes on piezoelectric transducer elements stacked in a tube shape, and expands and contracts by applying a voltage due to a so-called piezoelectric effect. As shown in FIGS. 2 and 3, the load-loading actuator 8 is disposed inside the lateral groove 14, one end of which is on the side wall of the lateral groove 14 and the other end is on the side wall of the T block 13 with an adhesive or the like. Each is fixed. As a result, when a voltage is applied to the load load actuator 8 to expand and contract, opposite forces are applied to the base block 12 and the T block 13 along the axial direction of the load load actuator 8. At this time, since one end of the base block 12 is supported by the support member 9 so as not to move, the T block 13 moves in a direction away from or closer to the base block 12, and is pulled or pulled against the test piece 2. A compressive load is applied. Further, as shown in FIG. 3, the load-loading actuator 8 is arranged so that the top portion thereof is located on the same plane as the upper surface of the base block 12 and the upper surface of the T block 13. Thus, by arranging the load-loading actuator 8 so as to be embedded in the base block 12, the test piece 2 disposed at the substantially central portion in the thickness direction of the base block 12 and the T block 13 Only a tensile or compressive load is applied, and a load that bends the test piece 2 in the vertical direction is less likely to be applied.

  The load loading means is not limited to the tensile test means 4 of this embodiment. For example, although not shown in detail in the drawing, the test piece 2 is sandwiched from both sides by two block members, and the test in one block member is performed. The piezoelectric element actuator may be placed in contact with the end opposite to the piece 2, and a compression force may be applied to the test piece 2 by applying a voltage to the piezoelectric element actuator to expand and contract. Good.

  The minute load detection means 5 detects the magnitude of the load applied to the test piece 2 by the tensile test means 4, and FIG. 5 is a diagram showing the configuration of the minute load detection means 5. As shown in the figure, the minute load detecting means 5 is configured as a cantilever mechanism 24 that detects minute distortions generated in the base block 12. The cantilever mechanism 24 includes a cantilever main body 26 arranged by bringing a probe 25 projecting from a tip portion into contact with the base block 12 and a canceling actuator (piezoelectric element) for canceling the bending generated in the cantilever main body 26. (Actuator) 27, a displacement detector 28 for detecting the amount of deflection of the cantilever body 26 and generating a displacement signal, an amplifier 29 for amplifying the displacement signal, and applying to the canceling actuator 27 based on the amplified displacement signal. A servo unit 30 that feedback-controls the voltage and a zero point adjustment micrometer 31 for adjusting the position of the base block 12 in the initial state are provided.

  The cantilever main body 26 is for detecting a minute distortion generated in the base block 12 when a load is applied. As shown in FIG. 5, a sharp-shaped probe 25 is provided at the tip of the cantilever main body 26. ing. The cantilever body 26 has a base end attached to a canceling actuator 27 and is cantilevered, and a tip 25 of the probe 25 is placed in contact with the load-loading direction edge 32 of the base block 12. ing. As a result, when a load is applied and the base block 12 is distorted, the cantilever main body 26 is slightly bent by being pressed by the base block 12. In this embodiment, the probe 25 of the cantilever main body 26 is brought into contact with the base block 12. However, the probe 25 is arranged close to the load loading direction edge 32 of the base block 12, and the probe 25 and the base 25 are arranged. It may be used that the cantilever body 26 bends due to a change in atomic force acting between the block 12 and the block 12.

  The canceling actuator 27 is for canceling the bending generated in the cantilever main body 26. The cancellation actuator 27 has the same configuration and function as the load load actuator 8, and is arranged in parallel with the load direction as shown in FIG. The cantilever body 26 is attached to the other end. By applying a voltage to the canceling actuator 27 to expand and contract, it is possible to adjust the position of the cantilever main body 26 in the range of 1 nanometer or less to several micrometers and control the amount of deflection. . FIG. 6 is a schematic plan view showing an example of the operation of the cancellation actuator 27. As shown in FIG. 6A, for example, when a strain is generated due to a load applied to the base block 12, the cantilever body 26 arranged with the probe 25 in contact with the base block 12 has only dx. Deflection occurs. At this time, as shown in FIG. 6B, the canceling actuator 27 is contracted by dx under the control of the servo unit 30, and the cantilever body 26 moves in a direction away from the base block 12, whereby the cantilever The bending of the main body 26 is cancelled.

  The displacement detection unit 28 detects the amount of bending of the cantilever body 26. As shown in FIG. 7, the displacement detector 28 forms a so-called Wien bridge by the piezoelectric resistance thin film 33, the resistance R 1, the resistance R 2, the variable resistance R 3, and the power source 34 attached to the surface of the cantilever body 26. It will be. The piezoresistive thin film 33 is a thin-film member made of a piezoelectric conversion element, and changes its resistivity by receiving stress due to a so-called piezoresistive effect. By sticking the piezoelectric resistance thin film 33 to the cantilever body 26, when the cantilever body 26 is bent, the resistance value of the piezoelectric resistance thin film 33 changes in proportion to the amount of the bending. Here, the resistance value of the variable resistor R3 is adjusted so that the displacement voltage becomes 0 when the amount of bending of the cantilever body 26 is 0, that is, when the load applied to the test piece 2 is 0. Thereby, the amount of bending of the cantilever main body 26 can be detected as a change in resistance of the piezoelectric resistance thin film 33.

  FIG. 8 is a diagram illustrating a configuration of a displacement detection unit 35 according to another embodiment. As shown in the figure, the displacement detector 35 amplifies the excitation piezoelectric body 36 that vibrates the cantilever body 26, the piezoelectric thin film 37 attached to the cantilever body 26, and a displacement signal emitted from the piezoelectric thin film 37. And an amplifier 38 and a frequency detector 39 for measuring the frequency of the displacement signal. The excitation piezoelectric body 36 is a plate-like member made of a piezoelectric conversion element, and vibrates when a voltage is applied due to a so-called reverse piezoelectric effect. The excitation piezoelectric body 36 is attached to the proximal end portion of the cantilever main body 26. The piezoelectric thin film 37 is a thin-film member made of a piezoelectric conversion element, and generates a voltage by receiving stress due to a so-called piezoelectric effect. In the displacement detector 35, as shown in FIG. 8, an oscillation circuit C is constituted by the excitation piezoelectric member 36, the piezoelectric thin film 37, and the amplifier 38. Here, when bending occurs in the cantilever body 26, a displacement signal is generated from the piezoelectric thin film 37, and this displacement signal is amplified by the amplifier 38 and applied to the excitation piezoelectric body 36, whereby the excitation piezoelectric body 36 is Delay oscillation is supposed to occur. On the other hand, the frequency of the displacement signal emitted from the piezoelectric thin film 37 is measured by the frequency detector 39. Here, when the cantilever body 26 bends, the frequency of the displacement signal changes according to the amount of the bend, so that the bend amount of the cantilever body 26 can be detected as a change in the frequency of the displacement signal.

  The servo unit 30 performs feedback control of the voltage applied to the canceling actuator 27 based on the amount of bending of the cantilever body 26. That is, as shown in FIG. 5, the servo unit 30 applies the voltage applied to the canceling actuator 27 so as to cancel the deflection of the cantilever body 26 based on the displacement signals generated from the displacement detecting units 28 and 35. To control. At this time, by detecting the voltage required for cancellation as the displacement output of the servo unit 30, the amount of deflection of the cantilever body 26 can be converted into a voltage and measured in nanometer order. From the amount of bending of the cantilever body 26 and the spring constant of the cantilever body 26, the magnitude of the load applied to the test piece 2 can be calculated, and the magnitude of the load can be measured with higher accuracy. ing.

  The zero point adjusting micrometer 31 is for adjusting the position of the base block 12 so that the amount of bending of the cantilever main body 26 becomes zero in an initial state before applying a load to the test piece 2. As shown in FIG. 5, the zero-point adjusting micrometer 31 is provided on the support member 9 disposed in contact with the base block 12, and the operation moves the position of the base block 12 along the load load direction. Fine adjustment is possible. Thus, the position adjustment of the base block 12 in the initial state is performed in order to correct the hysteresis characteristic of the piezoelectric transducer. That is, the canceling actuator 27 is composed of a piezoelectric conversion element, and this piezoelectric conversion element has a hysteresis characteristic, that is, a characteristic in which the displacement characteristic of the element differs depending on whether the applied voltage is raised or lowered. For this reason, the cantilever body 26 may be displaced in the initial state. In this embodiment, this positional deviation is corrected, and the position of the base block 12 is adjusted so that the amount of bending of the cantilever body 26 is zero in the initial state.

  The scanning probe microscope 6 is a so-called atomic force microscope, and, as shown in FIG. 1, a cantilever 41 in which a base end is cantilevered and a probe 40 protrudes from a tip, and a probe And a scanner 42 for precisely scanning 40 in the XYZ axis direction. In the scanning probe microscope 6, the probe 40 is scanned on the surface of the test piece 2 in the XY-axis direction by the scanner 42, and the atomic force acting between the probe 40 and the test piece 2 is constant during this time. Thus, scanning in the Z-axis direction is controlled. At this time, the feedback amount in the Z-axis direction corresponding to the position in the XY-axis direction is detected as the output voltage of the scanner 42, and this is output on the screen as a three-dimensional image via the arithmetic unit, whereby the surface of the test piece 2 It is possible to measure the shape of the ultra-precision. Although detailed explanation is omitted here using this scanning probe microscope 6, a minute strain generated in the test piece 2 is measured by observing a change in the line pattern 18 provided on the surface of the test piece 2. . In addition to this result, it is possible to calculate the Young's modulus and Poisson's ratio, which are the mechanical characteristics of the test piece 2, from the measurement result by the minute load detecting means 5, that is, the magnitude of the load applied to the test piece 2. Yes. FIG. 9 is a graph showing the relationship between the magnitude P of the load detected by the load detection means 5 on the vertical axis and the amount of strain ε of the test piece 2 measured by the scanning probe microscope 6 on the horizontal axis. Yes, the Young's modulus of the test piece 2 can be obtained by obtaining the slope dP / dε of this curve.

  Next, a micromaterial testing apparatus according to Example 2 of the present invention will be described with reference to the drawings. FIG. 10 is a schematic plan view showing the micromaterial testing apparatus 50 according to the present embodiment. As shown in the figure, the micromaterial test apparatus 50 is also provided with a tensile test means (load load means) 51 and a minute load detection means (load detection means) 52, as with the micromaterial test apparatus 1. The minute load detection means 52 is configured as a cantilever mechanism 53. The cantilever mechanism 53 includes a rigid body 55 attached to one end of the block body 54, a cantilever main body 56 for detecting a minute displacement of the rigid body 55, and a cancellation for canceling the flexure generated in the cantilever main body 56. Actuator (piezoelectric actuator) 57, displacement detectors 28 and 35 for detecting the amount of deflection of the cantilever body 56 and generating a displacement signal, an amplifier 29 for amplifying the displacement signal, and canceling based on the amplified displacement signal The servo unit 30 feedback-controls the voltage applied to the control actuator 57, and the zero point adjustment micrometer 31 for adjusting the position of the base block 12 in the initial state. In FIG. 10, the same components as those in FIG. 5 are denoted by the same reference numerals, and detailed description thereof is omitted here.

  More specifically, as shown in FIG. 10, the rod-shaped rigid body 55 is disposed orthogonal to the load direction and is attached to the block body 54 at an attachment portion 58 provided at the center thereof. ing. Further, the cantilever main body 56 is arranged such that the proximal end portion is fixed to the support member 9 and the probe 59 protruding from the distal end portion is brought into contact with the rigid body 55. Also, a pair of canceling actuators 57 are arranged in parallel with the load direction, one end is on the side wall of the mounting groove 61 formed on the end of the block body 54, and the other end is one end of the rigid body 55. Are fixed to each.

  In the micromaterial testing apparatus 50 configured as described above, when a load is applied to the block body 54, the block body 54 is distorted, whereby the rigid body 55 is slightly displaced and is pressed by the rigid body 55 to be cantilevered. The main body 56 is bent. The amount of deflection of the cantilever body 56 is detected by the displacement detectors 28 and 35, and the displacement signal emitted from the displacement detectors 28 and 35 is amplified by the amplifier 29. The servo section 30 feedback-controls the voltage applied to each canceling actuator 57 so as to cancel the bending of the cantilever main body 56 based on the amplified displacement signal. Here, in the case of the present embodiment, a voltage is applied to each canceling actuator 57 to expand and contract, whereby the axial force of the canceling actuator 57 acts on both ends of the rigid body 55, respectively. The position of is finely adjusted. As a result, the distance between the cantilever body 56 and the rigid body 55 is adjusted to cancel the bending generated in the cantilever body 56. In this way, the amount of bending of the cantilever body 56 is controlled to be constant, and the amount of bending of the cantilever body 56 can be detected by detecting the voltage required for the cancellation as the displacement output of the servo unit 30. ing.

  As described above, according to the micromaterial testing apparatus 1, 50, the magnitude of a minute load applied to the test piece 2 is measured using the cantilever main bodies 26, 56. In order to detect the amount of deflection, the amount of change per applied voltage is very small and detected by converting the amount of deflection into a voltage using a high-resolution piezoelectric transducer. As a result, the amount of deflection of the cantilever bodies 26 and 56 can be measured on the order of nanometers, and the magnitude of the load applied to the test piece 2 as well as the Young's modulus and Poisson's ratio which are the mechanical properties of the test piece 2 can be determined. It is possible to measure with higher accuracy. In Examples 1 and 2, the Young's modulus and Poisson's ratio were obtained as an example of the mechanical properties of the test piece 2. However, the present invention is not limited to this, and the fatigue strength of the test piece 2 can also be obtained. In this case, the load load means 4 may be one that can repeatedly apply a tensile load to the test piece 2, and the load detection means 5 may measure the magnitude of the load applied by the load load means 4.

1 is a schematic perspective view showing a micromaterial testing apparatus 1 according to Example 1 of the present invention. FIG. 3 is a schematic plan view showing a tensile test means 4. The schematic longitudinal cross-sectional view which shows the AA cross section in FIG. The schematic longitudinal cross-sectional view which shows the BB cross section in FIG. FIG. 3 is a schematic plan view showing a minute load detection means 5. FIG. 6 is a schematic plan view showing an example of the operation of the cancellation actuator 27. The schematic diagram which shows the displacement detection part 28. FIG. The schematic diagram which shows the displacement detection part 35 which concerns on another Example. The figure which shows the relationship between the magnitude | size P of the load loaded on the test piece 2, and the distortion amount (epsilon) of the test piece 2. FIG. The schematic plan view which shows the micromaterial test apparatus 50 which concerns on Example 2 of this invention. The schematic perspective view which shows the micromaterial test apparatus 80 which concerns on a prior art example. FIG. 3 is a schematic plan view showing a tensile test mechanism 82.

Explanation of symbols

1,50 Micromaterial test equipment 2 Test piece 4,51 Tensile test means (load load means)
5,52 Minute load detection means (load detection means)
7, 54 Block body 8 Actuator for load loading (load bearing member)
9 Support member 12 Base block (one block body)
24, 53 Cantilever mechanism 26, 56 Cantilever body 32, 60 Load load direction edge 27, 57 Counteracting actuator (piezoelectric element actuator)
28, 35 Displacement detection unit 30 Servo unit 55 Rigid body

Claims (4)

In a micromaterial testing apparatus comprising: a load loading means for applying a tensile or compressive load to a test piece to be measured; and a load detection means for detecting the magnitude of a load applied by the load loading means. ,
The load loading means includes a pair of block bodies that respectively hold both end portions of the test piece, a load load member that loads the test piece by separating or approaching the block bodies, and the block bodies. A support member that immovably supports one of the block bodies,
The micro-material testing apparatus, wherein the load detecting means is a cantilever mechanism that detects strain generated in the one block body.   The cantilever mechanism includes a cantilever main body arranged with a tip portion in contact with or close to a load-loading direction edge of the one block body, one end at the base end of the cantilever main body, and the other end at the support member. An attached piezoelectric element actuator; a displacement detection unit that detects a deflection amount of the cantilever body; and a servo unit that controls a voltage applied to the piezoelectric element actuator so as to cancel the deflection of the cantilever body. The micromaterial testing apparatus according to claim 1, wherein   The cantilever mechanism includes a rigid body attached to the one block body, a cantilever main body arranged with a proximal end fixed to the support member and a distal end contacting or approaching the rigid body, and one end of the cantilever mechanism A piezoelectric element actuator having the other end attached to the rigid body on the block body, a displacement detection unit for detecting the amount of bending of the cantilever body, and a voltage applied to the piezoelectric element actuator so as to cancel the bending of the cantilever body The micromaterial testing apparatus according to claim 1, further comprising a servo unit for controlling.   4. The micromaterial testing apparatus according to claim 1, wherein the load loading means measures the fatigue strength of the test piece by repeatedly applying a load to the test piece.

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