JPWO2012153739A1 - Probe and measuring apparatus having the probe - Google Patents

Abstract

The vibrator 1 is in contact with the holding member 3 with a minimum contact area and is held by the holding member 3. The chip 2 is bonded to one end of the vibrator 1. The holding member 3 is supported by the support member 7, and the magnet 8 is bonded to the support member 7. The antennas 4 to 6 are wound around the outer periphery of the holding member 3. The resin member 9 covers the holding member 3, the antennas 4 to 6, the support member 7, and the magnet 8. The holding member 3, the antennas 4 to 6, the support member 7, the magnet 8, and the support member 9 are arranged so that one end of the vibrator 1 protrudes from the opening 111 of the case 11 to the outside. It can move integrally in the length direction. The top plate 12 is bonded to the case 11. The magnet 13 has the same polarity as the magnet 3 and is disposed in contact with the top plate 12 in the case 14.

Description

  The present invention relates to a probe and a measuring apparatus including the probe.

  Conventionally, an elastic constant measuring apparatus that measures an elastic constant of a sample by fixing a vibrator to a top plate with a spring is known (Patent Document 1).

In this elastic constant measuring apparatus, the ball bearing is fixed to the end of the vibrator opposite to the top plate side. In addition, a solenoid coil is wound around the case that houses the vibrator, and an electric field for vibrating the vibrator is applied to the vibrator by the solenoid coil.
JP 2005-201816 A Stephen R. Swanson, International Journal of Solids and Structures, 41, 1945 (2004). JR Willis, J. Mech, Phys. Solids, 14, 163 (1966).

  However, the conventional elastic constant measuring device has a problem that it is difficult to ensure stable vibration of the vibrator because the vibrator is fixed to the top plate by a spring.

  In addition, since the conventional elastic constant measuring apparatus is configured to apply a bias force to the sample by gravity when the vibrator contacts the sample, the bias force is applied to the sample from a direction different from the direction of gravity. In some cases, it is difficult to accurately measure the elastic constant.

  Therefore, the present invention has been made to solve such problems, and its purpose is to ensure stable vibration of the vibrator and to measure the elastic constant by applying a bias force to the sample from any direction. Is to provide a simple probe.

  Another object of the present invention is to provide a measuring apparatus provided with a probe capable of ensuring stable vibration of a vibrator and measuring an elastic constant by applying a bias force to a sample from an arbitrary direction. .

  According to the embodiment of the present invention, the probe includes a vibrator, a chip, a holder, first and second magnets, and first to third antennas. The vibrator has a rod-like shape and is made of a piezoelectric body. The chip is bonded to one end of the vibrator on the measured object side and has a hardness higher than that of the measured object. The holder contacts the vibrator with a minimum contact area in the circumferential direction of the vibrator, and holds a part of the vibrator corresponding to a vibration node of the vibrator. The first magnet is disposed on the other end side of the vibrator and is bonded to a support member that supports the holder. The second magnet is disposed at a desired distance from the first magnet in the length direction of the vibrator, and has the same polarity as the first magnet. The first antenna is connected to the ground potential. The second antenna applies an excitation voltage for exciting the vibration of the vibrator to the vibrator in cooperation with the first antenna. The third antenna receives an electric field generated in the vibrator due to the excitation voltage being applied to the vibrator as a voltage in cooperation with the first antenna. The first to third antennas are arranged in the vicinity of a part of the vibrator, and the chip has an arc shape protruding in the direction from the vibrator toward the object to be measured.

  The measuring apparatus according to the embodiment of the present invention includes a probe, a voltage source, and a detector. A probe consists of the probe of Claim 1. The voltage source outputs an excitation voltage to the second antenna. The detector detects the resonance frequency of the vibrator based on the received voltage received by the third antenna, and calculates the Young's modulus of the device under test based on the detected resonance frequency.

  Furthermore, the measuring apparatus according to the embodiment of the present invention includes a probe, a voltage source, and a detector. A probe consists of the probe of Claim 1. The voltage source outputs an excitation voltage to the second antenna. The detector detects a half width of a peak having a resonance frequency of the vibrator based on the received voltage received by the third antenna, or the vibrator attenuates based on the received voltage received by the third antenna. Detect the damping constant when

  Furthermore, the measuring apparatus according to the embodiment of the present invention includes a probe, a voltage source, and a determination device. A probe consists of the probe of Claim 1. The voltage source outputs a voltage having a frequency obtained by multiplying the resonance frequency of the vibrator by n (n is an integer of 2 or more) or a frequency obtained by multiplying the resonance frequency of the vibrator by 1 / n as an excitation voltage to the second antenna. . The determiner determines whether the resonance frequency of the vibrator is detected based on the reception voltage received by the third antenna.

  In the probe according to the embodiment of the present invention, the vibrator is held by the holder with a minimum contact area at a position corresponding to the vibration node of the vibrator. The vibrator applies a bias force to the object to be measured by the repulsive force generated by the first and second magnets having the same polarity. As a result, the vibrator vibrates freely, and the bias force applied to the object to be measured is constant even if the object to be measured is arranged at an arbitrary angle with respect to the vertical direction.

  Accordingly, stable vibration of the vibrator can be secured, and the elastic constant can be measured by applying a bias force to the object to be measured from an arbitrary direction.

It is sectional drawing which shows the structure of the probe by embodiment of this invention. FIG. 2 is a plan view of a vibrator, a holding member, and an antenna viewed from the magnet side shown in FIG. 1. FIG. 2 is an enlarged view of a vibrator and a chip shown in FIG. FIG. 2 is a perspective view of a vibrator, a chip, a holding member, a support member, a magnet, and a resin member shown in FIG. It is a 1st process drawing which shows the manufacturing method which manufactures the probe shown in FIG. FIG. 6 is a second process diagram illustrating a manufacturing method for manufacturing the probe illustrated in FIG. 1. FIG. 6 is a third process diagram illustrating a manufacturing method for manufacturing the probe illustrated in FIG. 1. FIG. 8 is a fourth process diagram illustrating a manufacturing method for manufacturing the probe illustrated in FIG. 1. It is a conceptual diagram for demonstrating operation | movement of the probe shown in FIG. It is a 1st conceptual diagram for modeling the vibration of a vibrator. It is a 2nd conceptual diagram for modeling the vibration of a vibrator. It is a block diagram of the elastic constant measuring apparatus by embodiment of this invention. It is a timing chart of a burst wave and a trigger signal. It is a flowchart for demonstrating the measuring method of a Young's modulus. It is a figure which shows the relationship between an amplitude and a frequency. It is a figure which shows the relationship between the measured Young's modulus and the reported Young's modulus. It is a figure which shows the damping characteristic of a vibrator | oscillator. It is sectional drawing which shows the specific example of a to-be-measured object. It is a flowchart for demonstrating operation | movement when a defect is detected using the half value width of the peak which has a resonant frequency. It is a flowchart for demonstrating operation | movement when a defect is detected using an attenuation constant. It is a conceptual diagram which shows the displacement of the burst wave and defect when the defect is formed in the to-be-measured object. It is a figure which shows the relationship between an amplitude and a frequency. It is a flowchart for demonstrating the operation | movement which detects a defect using a harmonic. It is sectional drawing of the other vibrator | oscillator in embodiment of this invention. It is sectional drawing which shows the other mounting method of an antenna. It is sectional drawing which shows the holding method of a vibrator | oscillator. It is sectional drawing which shows another holding | maintenance method of a vibrator | oscillator. It is a figure which shows the relationship between a measurement depth and the radius of a chip | tip. It is sectional drawing which shows the example which mounted | wore the vibrator | oscillator with the several chip | tip. It is sectional drawing which shows the structure of another probe by embodiment of this invention. It is a conceptual diagram which shows the application example of the probe shown in FIG.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a cross-sectional view showing a configuration of a probe according to an embodiment of the present invention. Referring to FIG. 1, a probe 10 according to an embodiment of the present invention includes a vibrator 1, a chip 2, a holding member 3, antennas 4 to 6, a support member 7, magnets 8 and 13, and a resin. A member 9, cases 11 and 14, and a top plate 12 are provided.

The vibrator 1 has a quadrangular prism shape, and is made of, for example, a single crystal of langasite (La ₃ Ga ₅ SiO ₁₄ ) or quartz. That is, the vibrator 1 is made of a piezoelectric body. The vibrator 1 is held by the holding member 3, one end of which protrudes to the outside through the opening 111 of the case 11, and the other end side is disposed in the space 7 </ b> A in the support member 7. In this case, one end of the vibrator 1 protrudes outward from the bottom surface 11A of the case 11 by about 5 mm, for example.

  The vibrator 1 has a size of 2.0 mm × 2.0 mm × 20.0 mm. Furthermore, when the vibrator 1 is made of Langasite, the [100] direction of the Langasite is the longitudinal direction of the vibrator 1.

  The chip 2 is made of, for example, tungsten carbide, and is bonded to one end of the vibrator 1 with an adhesive. The chip 2 is harder than the object to be measured.

  The holding member 3 has a substantially circular planar shape, and holds a substantially central portion of the vibrator 1 in the length direction of the vibrator 1 by a method described later. The substantially central portion of the vibrator 1 is a position where a node of a fundamental mode of vibration exists. Accordingly, the holding member 3 holds a part of the vibrator 1 corresponding to the vibration node of the vibrator 1.

  The antenna 4 has one end wound around the holding member 3 and pulled out through the resin member 9 and the cases 11 and 14, and the other end connected to the ground potential.

  The antenna 5 has one end disposed on one side of the antenna 4 in the length direction of the vibrator 1 and is wound around the holding member 3. The antenna 5 is pulled out through the resin member 9 and the cases 11 and 14.

  The antenna 6 has one end disposed on the other side of the antenna 4 in the length direction of the vibrator 1 and is wound around the holding member 3. The antenna 6 is pulled out through the resin member 9 and the cases 11 and 14.

  Each of the antennas 4 to 6 has a diameter of 1 mm, for example, and is wound around the holding member 3 only once.

  The support member 7 has a hollow cylindrical shape, is fixed to the magnet 8 and supports the holding member 3. The magnet 8 is bonded to the support member 7.

  The resin member 9 is made of acrylic, for example, and is disposed between the holding member 3, the support member 7, the magnet 8, and the case 11, and covers the holding member 3, the antennas 4 to 6, the support member 7, and the magnet 8. A space 15 is formed between the magnet 8 and the resin member 9 and the top plate 12, and the vibrator 1, the chip 2, the holding member 3, the antennas 4 to 6, the support member 7, the magnet 8 and the resin. The member 9 can move integrally in the length direction of the vibrator 1. In this case, portions of the antennas 4 to 6 arranged in the space 15 are actually formed in a spiral shape, and the vibrator 1, the chip 2, the holding member 3, the antennas 4 to 6, and the support member. 7, the magnet 8 and the resin member 9 are configured to be movable in the length direction of the vibrator 1.

  Further, a space 16 is formed below the holding member 3 between the vibrator 1 and the resin member 9, and the space 16 communicates with the opening 111 of the case 11.

  The case 11 is made of a hollow cylindrical Teflon (registered trademark) and has an opening 111. The case 11 is fixed to the top plate 12 on the side opposite to the opening 111.

  The top plate 12 is made of acrylic, for example, and is fixed in the case 14. The magnet 13 has the same polarity as the magnet 8. The magnet 13 is fixed in the case 14 in contact with the top plate 12.

  The case 14 is made of acrylic, for example, and covers a part of the case 11, the top plate 12, and the magnet 13.

  FIG. 2 is a plan view of the vibrator 1, the holding member 3, and the antennas 4 to 6 viewed from the magnet 8 side shown in FIG.

  With reference to FIG. 2, the holding member 3 includes an O-ring 31 and a fixture 32. The O-ring 31 is made of nitrile rubber, for example. Nitrile rubber is a copolymer of acrylonitrile and 1,3-butadiene.

  The vibrator 1 has a substantially square cross-sectional shape. The O-ring 31 is arranged around the vibrator 1 so as to contact the four vertices of the square of the vibrator 1. As described above, the O-ring 31 contacts the vibrator 1 with a minimum contact area in the circumferential direction of the cross-sectional shape of the vibrator 1 when the vibrator 1 is cut in a direction orthogonal to the length direction of the vibrator 1. . In this case, the vibrator 1 and the O-ring 31 may be in point contact at four vertices or may be in surface contact at four corners. The point contact or surface contact depends on the hardness of the O-ring 31. The harder the O-ring 31, the easier the vibrator 1 and the O-ring 31 are in point contact. The softer the transducer 1 and the O-ring 31 are in surface contact.

  The fixture 32 has a donut-like planar shape and is made of, for example, an acrylic resin. The fixture 32 is arranged around the O-ring 31.

  The antennas 4 to 6 are wound only once around the fixture 32.

  FIG. 3 is an enlarged view of the vibrator 1 and the chip 2 shown in FIG. Referring to FIG. 3, chip 2 has a thin spherical piece cross-sectional shape. The chip 2 has, for example, a diameter of 1 to 2 mm and a thickness of about 0.3 mm.

  4 is a perspective view of the vibrator 1, the chip 2, the holding member 3, the support member 7, the magnet 8, and the resin member 9 shown in FIG. In FIG. 4, the antennas 4 to 6 are omitted.

  With reference to FIG. 4, the vibrator 1 is held by a holding member 3, and the holding member 3 is connected to a magnet 8 by a support member 7. The resin member 9 is formed in a substantially cylindrical shape so as not to contact the vibrator 1 but to contact the holding member 3, the support member 7 and the magnet 8 and cover the holding member 3, the support member 7 and the magnet 8. The resin member 9 has a bottom surface 9 </ b> A on the chip 2 side, and a space 16 between the resin member 9 and the vibrator 1. As a result, the holding member 3, the support member 7, the magnet 8 and the resin member 9 constitute an integrated object, and the vibrator 1 has an O-ring 31 (not shown in FIG. 4) in the integrated holding member 3. Is held only by.

  Accordingly, the vibrator 1, the chip 2, the holding member 3, the support member 7, the magnet 8, and the resin member 9 can be moved integrally in the length direction of the vibrator 1.

  5 to 8 are first to fourth process diagrams showing a manufacturing method for manufacturing the probe 10 shown in FIG.

  Referring to FIG. 5, when the manufacture of the probe 10 is started, a langasite having a quadrangular prism shape is cut out from a lump of single crystal of langasite to produce the vibrator 1 (step (a)). In this case, the langasite is cut out so that the length direction is the direction of [100].

  Then, the O-ring 31 is attached to the substantially central portion of the vibrator 1 (step (b)), and the fixture 32 having a donut shape is attached around the O-ring 31 (step (c)).

  Thereafter, a thin sphere piece (thickness: about 0.3 mm) chip 2 is manufactured, and the manufactured chip 2 is bonded to one end of the vibrator 1 with an adhesive. Further, the other end side of the vibrator 1 is put into a support member 7 having a hollow cylindrical shape, and the holding member 3 (O-ring 31 and fixture 32) is bonded to the support member 7 with an adhesive. Further, the magnet 8 is bonded to the support member 7 with an adhesive (step (d)). In this way, the magnet 8 is bonded to the support member 7 that supports the O-ring 31.

  Subsequently, the antennas 4 to 6 are wound only once around the fixture 32 (step (e)).

  Referring to FIG. 6, after step (e), vibrator 1, chip 2, holding member 3, a part of antennas 4-6, support member 7 and magnet 8 are placed in container 20 (step (f )), A resin made of acrylic is filled into the container 20. Then, the filled resin is dried. Thereby, the resin member 9 formed in a cylindrical shape in contact with the holding member 3, a part of the antennas 4 to 6, the support member 7 and the magnet 8 is produced (step (g)).

  Thereafter, the vibrator 1, the chip 2, the holding member 3, the antennas 4 to 6, the support member 7, the magnet 8, and the resin member 9 are mounted in the case 11 (step (h)).

  Referring to FIG. 7, after step (h), a hole is made in case 11, and antennas 4-6 are taken out of case 11 through antennas 4-6 in the hole (step (i)).

  And the top plate 12 is adhere | attached on the case 11 with an adhesive agent (process (j)). Thereafter, the case 14 is produced by injection molding (step (k)). The case 14 has recesses 141 and 142. The recess 141 has a substantially square planar shape, and the recess 142 has a substantially circular planar shape.

  Referring to FIG. 8, after step (k), magnet 13 is mounted in recess 141 of case 14 (step (l)).

  Then, a hole is made in the case 14, and the antennas 4 to 6 are passed through the holes, a part of the case 11 and the top plate 12 are put in the recess 142, and a part of the case 11 and the top plate 12 are placed in the case 14. Attach to. Thereby, the probe 10 is completed (step (m)).

  FIG. 9 is a conceptual diagram for explaining the operation of the probe 10 shown in FIG. With reference to (a) of FIG. 9, since the magnet 13 has the same polarity as the magnet 8, a repulsive force acts between the magnets 8 and 13. Since the probe 10 is not in contact with the device under test 30, the resin member 9 is pushed toward the opening 111 of the case 11 by the repulsive force RF that the magnet 8 receives from the magnet 13, and the bottom surface 9 </ b> A of the resin member 9. Is in contact with the case 11. Further, one end of the vibrator 1 and the chip 2 are out of the case 11.

  On the other hand, when the probe 10 is brought into contact with the upper surface 30 </ b> A of the device under test 30, the device under test 30 is pushed by the total force Fall of the gravity G and the repulsive force RF applied to the probe 10. However, since the repulsive force RF is sufficiently larger than the gravity G, the influence of gravity hardly affects the force Fall. Due to the force Fall, the vibrator 1, the chip 2, the holding member 3, the antennas 4 to 6, the support member 7, the magnet 8, and the resin member 9 generate a force Frev of the same magnitude as the force Fall from the object to be measured 30 as a repulsive force RF. Receive in the opposite direction. As a result, the vibrator 1, the chip 2, the holding member 3, the antennas 4 to 6, the support member 7, the magnet 8, and the resin member 9 move by δ in the direction opposite to the repulsive force RF (see FIG. 9B). . This moved distance δ corresponds to the amount by which the vibrator 1 and the chip 2 are pushed.

  FIG. 9 shows the case where the device under test 30 is arranged in a horizontal plane and the probe 10 is brought into contact with the upper surface 30 </ b> A of the device under test 30. However, even in the case where the device under test 30 is arranged so as to have an arbitrary angle with respect to the vertical direction, the probe 10 is measured by the repulsive force RF until the bottom surface 11A of the case 11 contacts the device under test 30. It is pushed in the direction of 30. Since the gravity G is sufficiently smaller than the repulsive force RF, the chip 2 can be pushed into the device under test 30 with the same force in this case as well. Thus, the magnet 13 is disposed at a position away from the magnet 8 by a desired distance at which the repulsive force RF acting on the magnet 8 is the same. As a result, the vibrator 1, the chip 2, the holding member 3, the antennas 4 to 6, the support member 7, the magnet 8, and the resin member 9 move by δ in the direction opposite to the repulsive force RF.

  As described above, in the embodiment of the present invention, since the vibrator 1 is held by the O-ring 31, even if the probe 10 is pressed against the device under test 30, the vibrator 1 is not attached to the device under test 30. The vibrator 1, the chip 2, the holding member 3, the antennas 4 to 6, the support member 7, the magnet 8, and the resin member 9 move by δ in the direction opposite to the repulsive force RF without moving in the in-plane direction. Therefore, even if the device under test 30 is arranged so as to form an arbitrary angle with the vertical direction, the pushing amount can be kept constant.

  A method for measuring the Young's modulus of the DUT 30 using the probe 10 will be described.

As described above, the resonator 1 is made of langasite, which has a trigonal crystal structure and has six independent elastic constants C ₁₁ , C ₁₂ , C ₁₃ , C ₁₄ , C _33. , C ₄₄ , two piezoelectric constants e ₁₁ , e ₁₄ , and two dielectric constants ε ₁₁ , ε ₃₃ .

Table 1 shows the elastic constants C ₁₁ , C ₁₂ , C ₁₃ , C ₁₄ , C ₃₃ , C ₄₄ , piezoelectric constants e ₁₁ , e ₁₄ , dielectric constants ε ₁₁ , ε _33, and density ρ of Langasite.

In Table 1, the units of the elastic constants C ₁₁ , C ₁₂ , C ₁₃ , C ₁₄ , C ₃₃ , C ₄₄ are [GPa], and the units of the piezoelectric constants e ₁₁ , e ₁₄ are [C / m ² ], the dielectric constants ε ₁₁ and ε ₃₃ are [10 ⁻²² F / m ² ], and the density ρ is [kg / m ² ].

  10 and 11 are first and second conceptual diagrams for modeling the vibration of the vibrator 1, respectively.

  Assuming that there is no vibration attenuation, it is assumed that the vibrator 1 has an elongated structure that can be sufficiently assumed to be longitudinal vibration.

As the spatial axis, as shown in FIG. 10A, the longitudinal direction of the vibrator 1 is the Z-axis, the length of the vibrator 1 is L, the Young's modulus in the Z-axis direction is E, and the vibrator 1 The cross-sectional area is A, the density of the vibrator 1 is ρ, and the variation in the Z direction at the position Z = Z is u _z = u (z, t). In this case, the motion equation of vibration of the vibrator 1 is expressed by the following formula.

  And the general solution of Formula (1) is represented by the following formula.

In equation (2), ω is the angular frequency of the vibrator 1, k is the wave number of vibration, and C ₁ and C ₂ are constants.

  The angular frequency and the wave number are expressed by the following equations using the frequency f and the sound velocity v.

  In Expression (3), ρ is the density of the vibrator 1, and E is the Young's elastic modulus of the vibrator 1.

Next, let us consider a state in which the vibrator 1 is in contact with the device under test 30 as shown in FIG. Here, the spring constant K represents the contact rigidity between the chip 2 and the device under test 30. In this case, the boundary conditions are Z = 0 and σ (0) = 0. On the other hand, when Z = L, the restoring force of the spring is taken into consideration, as shown in FIG. The compressive stress σ and the elastic force of the spring balance. Thereby, when Z = L, Aσ + Ku _z = 0 holds. From these conditions, the following equation is derived.

  Substituting the above calculation results in the following equation.

In Equation (5), K _osc corresponds to the spring constant of the vibrator 1 in the static load in the vertical direction. Therefore, the right side of equation (5) represents the ratio of the stiffness of the vibrator 1 to the contact stiffness, and in order to increase the sensitivity of the probe 10, the value on the right side is increased, that is, K _osc = EA / L. Just make it smaller. Therefore, the crystal orientation is determined so that the Young's modulus E in the longitudinal direction of the vibrator 1 becomes small.

  Here, the contact stiffness K is expressed by the following equation according to Hertz's contact theory (see Non-Patent Documents 1 and 2).

In Equation (6), F is the bias force, R is the radius of the tip 2, and E ^* is the effective Young's modulus.

The effective Young's modulus E ^* is expressed by the following equation.

In equation (7), E _spe is the Young's modulus of the device under test 30, E _tip is the Young's modulus of the chip 2, ν _spe is the Poisson's ratio of the device under test 30, and ν _tip is It is the Poisson's ratio of chip 2.

Therefore, the left side of the equation (5) includes the resonance frequency from the equation (3), and the right side of the equation (5) includes the Young's modulus E _spe of the device under test 30 from the equations (6) and (7). Therefore, by measuring the resonance frequency f of the vibrator 1, the Young's modulus E _spe of the device under test 30 can be obtained.

That is, since the bias force F, the radius of the chip 2, the length L of the vibrator 1, the wave number k, the Poisson ratio ν _spe of the device under test 30 and the Poisson ratio ν _tip of the chip 2 are known, the resonance frequency f By calculating = fosc by the method described later, the Young's modulus E _spe of the device under test 30 can be calculated.

  FIG. 12 is a configuration diagram of an elastic constant measuring apparatus according to the embodiment of the present invention. Referring to FIG. 12, elastic constant measuring apparatus 100 according to the embodiment of the present invention includes a probe 10, a voltage source 40, and a detector 50.

  The probe 10 is as described above. The voltage source 40 is connected to the other end of the antenna 5 of the probe 10. The voltage source 40 is composed of, for example, a synthesizer (NF circuit design block, WF1974). Then, the voltage source 40 transmits a burst wave (about 10 ms) of the voltage Vv having a frequency component f (about 0.1 MHz) to vibrate the vibrator 1 to the antenna 5 and outputs a trigger signal to the detector 50. To do. In this case, the voltage Vv is, for example, a voltage whose difference between the maximum value and the minimum value is 50V.

  The detector 50 is connected to the other end of the antenna 6 and includes, for example, a digitizer (National Instruments, NIUSB-5133). The detector 50 receives a trigger signal from the voltage source 40. The detector 50 receives from the antenna 6 a received signal of the polarization electric field generated when the vibrator 1 vibrates after a certain time (for example, 10 μs) from the rising edge of the trigger signal. Thereafter, the detector 50 performs a Fourier transform on the received signal, and obtains an amplitude A corresponding to the vibration frequency f.

The detector 50 obtains the resonance frequency fosc of the vibrator 1 based on the relationship between the vibration frequency f and the amplitude A when the vibration frequency f is changed, and calculates the resonance frequency fosc and the equations (3) and (5). The Young's modulus E _spe of the device under test 30 is calculated using (7).

Details of the Fourier transform are as follows. The record length of the detector 50 is 2500 (Sampling), and the sample rate is 2.0 × 10 ⁵ (Sampling / s). The detector 50 creates digital data of trigonometric functions (cos (2πf · t), sin (2πf · t)) in accordance with the waveform of the received signal received from the antenna 6 and the frequency f, and the created data Perform a Fourier transform by accumulating trigonometric functions. More specifically, the detector 50 performs a Fourier transform by the following method.

  Assuming that the waveform of the received signal is f (t), the detector 50 integrates the trigonometric function according to the following equation.

Actually, since the integration interval is a finite interval and the received signal is a digital signal, the detector 50 integrates the trigonometric function according to the following equation to obtain I ₁ and I ₂ .

  And the detector 50 calculates | requires the amplitude A by following Formula.

  FIG. 13 is a timing chart of the burst wave and the trigger signal. Referring to FIG. 13, each of burst waves BW1 and BW2 has, for example, the number of 1000 cycles and a length of 10 ms. Each of the burst waves BW1 and BW2 has a difference between the maximum value and the minimum value of 50V, and has a frequency f (= 0.1 MHz) at which the vibrator 1 is desired to vibrate. Furthermore, the interval d between the burst wave BW1 and the burst wave BW2 is, for example, 10 ms.

  The trigger signal TRG becomes L (logic low) level at timing t1 when the burst wave BW1 rises, and becomes H (logic high) level at timing t2 when the burst wave BW1 falls, and at the rise of the burst wave BW2. It becomes L level at a certain timing t3 and becomes H level at a timing t4 which is the falling edge of the burst wave BW2. The detector 50 receives a reception signal from the antenna 6 from timing t2 to timing t3. Accordingly, the detector 50 starts to receive the received signal from the antenna 6 at a timing t2 after a certain time from the timing t1 when the burst wave BW1 is applied to the vibrator 1.

  FIG. 14 is a flowchart for explaining a method of measuring Young's modulus. In the following, a method for measuring the Young's modulus will be described on the assumption that the probe 10 is pressed against the device under test 30 and the tip 2 is in contact with the device under test 30.

  Referring to FIG. 14, when measurement of Young's modulus is started, the frequency measurement range, the frequency changing interval, the number of burst wave marks, and the burst wave interval are set in voltage source 40 (step S1). .

  The voltage source 40 determines a frequency component to vibrate the vibrator 1 within the frequency measurement range, and a burst composed of the voltage Vv having the determined frequency component and the number of marks set in step S1. A wave is generated, and the generated burst wave is transmitted to the antenna 5 at the burst wave interval set in step S1. At the same time, the voltage source 40 outputs the trigger signal TRG to the detector 50 (step S2).

  Then, the antenna 5 cooperates with the antenna 4 to apply the voltage Vv to the vibrator 1, and an oscillating electric field is generated in the vibrator 1. As a result, a piezoelectric phenomenon occurs in the vibrator 1 by the generated oscillating electric field, and the vibrator 1 vibrates (step S3).

  The antenna 6 cooperates with the antenna 4 to detect a polarization electric field generated along with the vibration of the vibrator 1 as a voltage (step S4).

  The detector 50 receives a reception signal (= voltage) from the antenna 6 (step S5). In this case, the detector 50 receives a received signal from the antenna 6 between timing t2 and timing t3 shown in FIG.

  Thereafter, the detector 50 performs a Fourier transform on the received signal by the method described above to obtain an amplitude A with respect to the vibration frequency f (step S6).

  Then, the voltage source 40 determines whether or not the frequency f has been changed in all of the measurement range (step S7).

  When it is determined in step S7 that the frequency f has not been changed in all of the measurement range, the voltage source 40 changes the frequency f within the measurement range (step S8). In this case, the voltage source 40 changes the frequency f by adding the frequency change interval set in step S1 to the original frequency.

  Thereafter, the series of operations returns to step S2, and step S2 to step S8 described above are repeatedly executed until it is determined in step S7 that the frequency f has been changed in all of the measurement range.

  When it is determined in step S7 that the frequency f has been changed in all of the measurement range, the detector 50 plots the relationship between the frequency f and the amplitude A, and sets the frequency at which the amplitude A is maximum to the resonance frequency fosc. (Step S9).

Thereafter, the detector 50 calculates the Young's modulus E _spe of the device under test 30 using the detected resonance frequency fosc and equations (3), (5) to (7) (step S10). This completes the measurement of Young's modulus.

  FIG. 15 is a diagram illustrating the relationship between amplitude and frequency. 15A and 15B, the vertical axis represents amplitude, and the horizontal axis represents frequency.

  A curve k1 shows the relationship between amplitude and frequency when the O-ring is attached to the transducer 1 of the probe 10 according to the embodiment of the present invention, and a curve k2 shows the elastic constant measurement disclosed in Patent Document 1. The relationship between amplitude and frequency when an O-ring is attached to the vibrator of the apparatus is shown.

  Furthermore, the curve k3 shows the relationship between the amplitude and the frequency when the O-ring is not attached to the transducer 1 of the probe 10 according to the embodiment of the present invention, and the curve k4 shows the elastic constant measurement disclosed in Patent Document 1. The relationship between the amplitude and the frequency when the O-ring is not attached to the vibrator of the apparatus is shown.

  Referring to FIG. 15, the vibration of the transducer 1 of the probe 10 has a peak at one frequency whether the O-ring is attached to the transducer 1 or not (see curves k1 and k3). On the other hand, the vibration of the vibrator disclosed in Patent Document 1 has peaks at a plurality of frequencies (see curves k2 and k4). In particular, when an O-ring is attached, the vibration of the vibrator disclosed in Patent Document 1 has peaks at a plurality of frequencies centering on 0.111 (MHz) (see curve k2).

  Table 2 shows the input voltage, integration interval length, and burst wave length when measuring the resonance frequency. Table 3 shows the resonance frequency and the Q value.

  In the present invention, the input voltage is 10 V (difference between the maximum value and the minimum value), the integration interval length is 12.5 ms, and the burst wave length is 10 ms. On the other hand, in the conventional example (Patent Document 1), the input voltage is 200 V (difference between the maximum value and the minimum value), the integration interval length is 0.4 ms, and the burst wave length is 0.2 ms. is there.

  As described above, in the present invention, the length of the integration interval and the length of the burst wave are significantly longer than in the prior art, and the input voltage is significantly reduced.

  Further, as shown in Table 3, in the present invention, the Q value is 1855 when the O-ring is not attached to the vibrator 1, and is 1587 when the O-ring is attached. On the other hand, in the conventional example (Patent Document 1), the Q value is 496.5 when the O-ring is not attached to the vibrator, and 283.3 when the O-ring is attached.

  Thus, in the conventional example, since the length of the burst wave is as short as 0.2 ms, a sufficient resonance state cannot be created, and the signal intensity does not increase even when a large voltage (up to 200 V) is used. .

  On the other hand, in the present invention, since the vibrator 1 easily vibrates, the length of the burst wave can be increased to 10 ms. Therefore, a high Q value can be obtained even at a low voltage (10 V).

  The Young's modulus was calculated from the resonance frequency fosc obtained using the probe 10 assuming that the vibration of the vibrator made of Langasite is a one-dimensional longitudinal vibration of a simple rod, and was 113.51 GPa.

  The Young's modulus in the [100] direction obtained from the elastic constant of Langasite is 114.03 GPa, and the difference from the actually measured value (= 113.51 GPa) is about 0.4%, which is sufficiently small. Therefore, the above-described method for obtaining Young's modulus is suitable for measuring Young's modulus.

  FIG. 16 is a diagram showing the relationship between the measured Young's modulus and the reported Young's modulus.

  In FIG. 16, the vertical axis represents the Young's modulus (= measured value) measured by the method described above, and the horizontal axis represents the reported Young's modulus (= reported value). Further, the radius of the chip 2 is 2 mm, and the bias force F is 0.455N. Further, in the langasite constituting the vibrator 1, the X-axis direction of the crystal coincides with the longitudinal direction, and the size is 2 mm × 2 mm × 20 mm.

  Referring to FIG. 16, the measured value shows a good agreement with the reported value. Moreover, the straight line shown in FIG. 16 represents that the measured value has a one-to-one correspondence with the reported value.

  As described above, by using the probe 10 according to the embodiment of the present invention, the Young's modulus of the object to be measured 30 can be accurately obtained by simply touching the object to be measured 30 without using any fitting parameter.

  In the above description, it has been described that the detector 50 detects the resonance frequency of the vibrator 1 and calculates the Young's modulus of the DUT 30 based on the detected resonance frequency. In the embodiment of the present invention, The detector 50 is not limited to this, and the peak half-value width FWHM having the resonance frequency of the vibrator 1 may be detected. In this case, the detector 50 detects the half-value width FWHM of the peak indicated by the curves k1 and k3 in FIG.

  The detector 50 may detect an attenuation constant α when the vibrator 1 is attenuated. FIG. 17 is a diagram illustrating the attenuation characteristics of the vibrator 1. The detector 50 receives a reception signal from the antenna 6 from timing t2 to timing t3 shown in FIG. Since the burst wave is not applied to the vibrator 1 from the timing t2 to the timing t3, the vibration of the vibrator 1 is attenuated as a vibration curve DCY shown in FIG.

Therefore, the detector 50 detects the vibration curve DCY, and detects the envelope EVL of the detected vibration curve DCY. The envelope EVL is usually represented by e ^−αt (α: attenuation constant, t: time).

Therefore, when detecting the envelope EVL, the detector 50 fits the detected envelope EVL with e- ^αt to detect the attenuation constant α.

  FIG. 18 is a cross-sectional view showing a specific example of the device under test 30. Referring to FIG. 18, the device under test 30 includes a main body portion 301 and a coating layer 302. The coating layer 302 is disposed on the main body 301 so as to cover the surface 301 </ b> A of the main body 301. Then, peeling portions 303 and 304 are formed between the main body portion 301 and the coating layer 302.

The tip 2 of the probe 10 is brought into contact with the surface 302A of the coating layer 302 of the object to be measured 30 to detect the attenuation constant α _h of the vibrator 1. Here, if the attenuation constant of the vibrator 1 when the peeling portions 303 and 304 are not formed is α ₀ , the attenuation constant α _h is larger than the attenuation constant α ₀ . The reason is as follows.

When the tip 2 of the probe 10 is brought into contact with the surface 302A of the coating layer 302 and the vibrator 1 is vibrated, the vibration of the vibrator 1 propagates to the coating layer 302 and the coating layer 302 also vibrates. Since 304 absorbs the vibration of the coating layer 302, the vibration of the coating layer 302 is easily attenuated. As a result, the vibration of the vibrator 1 is also easily attenuated, and the damping constant α _h of the vibrator 1 when the peeling portions 303 and 304 are formed on the object to be measured 30 has the peeling portions 303 and 304 formed. This is because it becomes larger than the attenuation constant α _{0 in the} case of no.

Therefore, it is possible to detect whether or not the peeling portions 303 and 304 (= defects) are formed on the measurement object 30 by the detector 50 measuring the attenuation constant α of the vibrator 1 by the method described above. In this case, if the detected attenuation constant α is larger than the attenuation constant α ₀ , the detector 50 detects that the peeling portions 303 and 304 are formed, and the detected attenuation constant α is substantially equal to the attenuation constant α ₀ . If they are equal, it is detected that the peeling portions 303 and 304 are not formed.

Further, the peak half-value width FWHM _h having the resonance frequency when the peeling portions 303 and 304 are formed is larger than the peak half-value width FWHM ₀ having the resonance frequency when the peeling portions 303 and 304 are not formed. growing. The reason is the same as the reason why the attenuation constant α _h of the vibrator 1 when the peeling portions 303 and 304 are formed is larger than the attenuation constant α ₀ when the peeling portions 303 and 304 are not formed. is there.

Therefore, whether or not the peeling portions 303 and 304 (= defects) are formed on the object to be measured 30 can also be detected by detecting the peak half width FWHM having the resonance frequency by the detector 50. In this case, if the half width when the peeling portions 303 and 304 are not formed is FWHM ₀ , the detector 50 forms the peeling portions 303 and 304 if the detected half width FWHM is larger than the half width FWHM _0. If the detected half-value width FWHM is substantially equal to the half-value width FWHM ₀ , it is detected that the peeling portions 303 and 304 are not formed.

  Thus, the presence or absence of a defect in the DUT 30 can be detected by detecting the half-value width FWHM of the peak having the resonance frequency or the attenuation constant α of the vibrator 1.

  When the detector 50 detects the attenuation constant α of a plurality of types of objects to be measured 30, it is possible to select the object to be measured 30 that matches the purpose by comparing the magnitudes of the attenuation constants α.

  For example, when the purpose is to prevent vibration or sound, the device under test 30 having a larger attenuation constant α may be selected. Further, when selecting a material to be used for the resonant device of the mobile phone, it is only necessary to select the device under test 30 having a smaller attenuation constant α.

  In addition, when the device under test 30 breaks, there is a timing at which the damping constant α suddenly increases immediately before the break, so the change over time of the damping constant α of the device under test 30 is measured, and the damping constant α suddenly increases. If it becomes larger, it may be determined that the device under test 30 may be broken, and the device under test 30 may be replaced. For example, in an airplane, the load is most applied to the boundary between the wing and the main body, and the base of the wing is most likely to break. Therefore, the time-dependent change of the attenuation constant α at the base of the wing is measured using the probe 10 to attenuate If the constant α increases rapidly, it is determined that the blade is broken, and the blade is replaced.

  As described above, the probe 10 can be used not only for measuring the Young's modulus of the object to be measured 30, but also for detecting defects of the object to be measured 30, material selection, non-destructive inspection, and the like.

FIG. 19 is a flowchart for explaining an operation when a defect is detected using a half width of a peak having a resonance frequency. In FIG. 19, the detector 50 holds in advance a peak half-value width FWHM ₀ having a resonance frequency when no defect (peeling portion 303, 304) is formed on the DUT 30. An operation for detecting a defect will be described as a premise.

  The flowchart shown in FIG. 19 is the same as the flowchart shown in FIG. 14 except that step S10 of the flowchart shown in FIG. 14 is replaced with steps S11 to S14.

  Referring to FIG. 19, when an operation for detecting a defect is started, the above-described steps S1 to S9 are sequentially executed. After step S9, the detector 50 detects the half-value width FWHM of the peak having the resonance frequency fosc (step S11).

Thereafter, the detector 50 determines whether or not the half width FWHM is larger than the half width FWHM ₀ (step S12).

In Step S12, when it is determined that the half-value width FWHM is larger than the half-value width FWHM ₀ , the detector 50 detects that a defect is formed in the object to be measured 30 (Step S13).

On the other hand, when it is determined in step S12 that the half-value width FWHM is not larger than the half-value width FWHM ₀ (that is, when the half-value width FWHM is determined to be substantially equal to the half-value width FWHM ₀ ), the detector 50 It is detected that no defect is formed on the device under test 30 (step S14).

  And the operation | movement which detects a defect is complete | finished after step S13 or step S14.

FIG. 20 is a flowchart for explaining an operation when a defect is detected using an attenuation constant. In FIG. 20, the detector 50 detects the defect on the assumption that the attenuation constant α ₀ when the defect (the peeling portions 303 and 304) is not formed on the DUT 30 is held in advance. The operation will be described.

  The flowchart shown in FIG. 20 is the same as the flowchart shown in FIG. 14 except that steps S6 to S10 in the flowchart shown in FIG. 14 are replaced with steps S15 to S19.

  Referring to FIG. 20, when an operation for detecting a defect is started, the above-described steps S1 to S5 are sequentially executed. After step S5, the detector 50 detects the envelope EVL of the received signal (= attenuation curve DCY) received from the antenna 6 (step S15).

Thereafter, the detector 50 fits the detected envelope EVL with e ^−αt to detect the attenuation constant α (step S16).

Then, the detector 50 determines the attenuation constant alpha is whether greater than the attenuation constant alpha ₀ (step S17).

In step S17, when the attenuation constant alpha is determined to be greater than the attenuation constant alpha _0, the detector 50 detects that the defect is formed on the measured object 30 (Step S18).

On the other hand, in step S17, when the attenuation constant alpha is not greater than the attenuation constant alpha ₀ (i.e., when the attenuation constant alpha is determined to substantially equal to the attenuation constant alpha _0), the detector 50 may be It is detected that no defect is formed on the measurement object 30 (step S19).

  And the operation | movement which detects a defect is complete | finished after step S18 or step S19.

  In the embodiment of the present invention, the voltage source 40 may transmit a burst wave BWh having a frequency half the resonance frequency to the antenna 5 as an excitation voltage. In this case, the burst wave BWh is composed of, for example, a sin wave having a frequency of 50 kHz.

  FIG. 21 is a conceptual diagram showing the burst wave BWh and the displacement of the defect when a defect is formed in the device under test 30. FIG. 22 is a diagram showing the relationship between amplitude and frequency.

  Referring to FIG. 21, voltage source 40 transmits burst wave BWh formed of a sin wave to antenna 5. In this case, the component SS1 of the burst wave BWh is a component that moves the vibrator 1 to the measured object 30 side, and the component SS2 is a component that moves the vibrator 1 to the opposite side of the measured object 30 side.

  When the vibration of the vibrator 1 is excited by the burst wave BWh while the tip 2 of the probe 10 is in contact with the object to be measured 30, the vibrator 1 does not resonate but is forced to vibrate. Propagated to the object 30. The peeling portions 303 and 304 of the DUT 30 are not displaced in the period in which the component SS1 is transmitted to the antenna 5, but are displaced in the period in which the component SS2 is transmitted to the antenna 5. Accordingly, the peeling portions 303 and 304 are periodically displaced, and a harmonic wave (= wave having a resonance frequency) is generated from the contact portion between the chip 2 and the DUT 30. Then, the generated harmonic wave is propagated to the vibrator 1, and the vibrator 1 resonates with the harmonic wave.

  As a result, the detector 50 detects the resonance frequency fosc based on the reception voltage received by the antenna 6 (see FIG. 22).

  If the peeling portions 303 and 304 are not formed on the DUT 30, even if the vibration of the vibrator 1 is excited by the burst wave BWh, the vibrator 1 does not resonate with the double wave. The resonance frequency fosc is not detected.

  Therefore, when the detector 50 detects the resonance frequency fosc when the vibration of the vibrator 1 is excited by the burst wave BWh having a half frequency of the resonance frequency fosc, the peeling portions 303 and 304 are attached to the object to be measured 30. If the formation is detected and the resonance frequency fosc is not detected, it is detected that the peeling portions 303 and 304 are not formed on the measurement object 30.

  Note that the frequency of the burst wave BWh is not limited to half the resonance frequency, and may be 1/3 times the resonance frequency, 1/4 times the resonance frequency, or the like. The frequency may be 1 / n (n is an integer of 2 or more) times the resonance frequency. Also in this case, if the detector 50 detects the resonance frequency fosc, the detector 50 detects that the peeling portions 303 and 304 are formed on the object to be measured 30, and if not, detects the resonance frequency fosc. It is detected that the peeling portions 303 and 304 are not formed.

  Further, the frequency of the burst wave BWh may be a frequency that is twice the resonance frequency, a frequency that is three times the resonance frequency, or the like, and may generally be a frequency that is n times the resonance frequency. In this case, the vibrator 1 resonates with a 1 / n harmonic by the mechanism described above. Accordingly, even when the vibration of the vibrator 1 is excited by the burst wave BWh having a frequency n times the resonance frequency, the detector 50 detects the resonance frequency fosc and causes the separation parts 303 and 304 to be measured on the object 30 to be measured. If the resonance frequency fosc is not detected, it is detected that the peeling portions 303 and 304 are not formed on the object to be measured 30.

  Therefore, in the embodiment of the present invention, when detecting whether or not a defect is formed in the device under test 30 by the harmonic wave, the voltage source 40 is a burst wave having a frequency n times the resonance frequency, or If a burst wave having a frequency 1 / n times the resonance frequency is transmitted as an excitation voltage to the antenna 5, and the detector 50 detects the resonance frequency fosc, peeling parts 303 and 304 are formed on the object to be measured 30. If the resonance frequency fosc is not detected, it is detected that the peeling portions 303 and 304 are not formed on the object to be measured 30.

  FIG. 23 is a flowchart for explaining an operation of detecting a defect using a harmonic wave. Referring to FIG. 23, when the operation for detecting a defect is started, detector 50 detects resonance frequency fosc according to steps S1 to S9 shown in FIG. 14 (step S21).

  The voltage source 40 transmits a burst wave BWh having a frequency n times the resonance frequency fosc of the vibrator 1 or a frequency 1 / n times the resonance frequency fosc of the vibrator 1 to the antenna 5, and a trigger signal is transmitted. Output to the detector 50 (step S22).

  Thereafter, the detector 50 receives the received signal from the antenna 6 (step S23), Fourier-transforms the received received signal, and obtains an amplitude corresponding to the vibration frequency (step S24).

  Subsequently, the detector 50 plots the relationship between the frequency f and the amplitude A (step S25).

  Then, the detector 50 determines whether or not there is a peak at the position of the resonance frequency (step S26).

  When it is determined in step S26 that there is a peak at the position of the resonance frequency, the detector 50 detects that a defect is formed in the DUT 30 (step S27).

  On the other hand, when it is determined in step S26 that there is no peak at the position of the resonance frequency, the detector 50 detects that no defect is formed in the device under test 30 (step S28).

  And the operation | movement which detects a defect is complete | finished after step S27 or step S28.

  FIG. 24 is a cross-sectional view of another vibrator according to the embodiment of the present invention. Referring to FIG. 24A, the probe 10 according to the embodiment of the present invention may include a vibrator 21 instead of the vibrator 1 and a holding member 3 </ b> A instead of the holding member 3.

  The vibrator 21 is made of langasite or quartz having a circular cross-sectional shape. The vibrator 21 has a diameter of 3 mm, for example, and has the same length as the vibrator 1. When the vibrator 21 is made of langasite, the X-axis direction (= [100] direction) of the crystal coincides with the longitudinal direction.

  The holding member 3 </ b> A includes a holding tool 33 and a fixing tool 34. The holder 33 includes holders 331 to 333, and each of the holders 331 to 333 includes, for example, nitrile rubber. The holders 331 to 333 hold the vibrator 21 from a direction that forms an angle of 120 degrees with each other at a substantially central portion in the length direction of the vibrator 21. In this case, each of the holders 331 to 333 holds the vibrator 21 in point contact with the vibrator 21. The fixture 34 is made of the same material as the fixture 32 and has a donut shape. The fixing tool 34 is arranged around the holding tool 33 and bonded to the holding tool 33.

  When the probe 10 includes the vibrator 21, the resin member 9 is in contact with the outer periphery of the fixture 34.

  Referring to FIG. 24B, the probe 10 according to the embodiment of the present invention may include a vibrator 22 instead of the vibrator 1 and a holding member 3 </ b> B instead of the holding member 3.

  The vibrator 22 is made of langasite or quartz having a regular triangular cross-sectional shape. The length of one side of the equilateral triangle is, for example, 3 mm, and the vibrator 22 has the same length as the vibrator 1. When the vibrator 22 is made of langasite, the X-axis direction (= [100] direction) of the crystal coincides with the longitudinal direction.

  The holding member 3 </ b> B includes an O-ring 35 and a fixture 36. The O-ring 35 is made of, for example, nitrile rubber, and is in contact with the three apexes of the triangle of the vibrator 22 at approximately the center in the length direction of the vibrator 22 to hold the vibrator 22. The fixture 36 is made of the same material as the fixture 32 and has a donut shape. The fixture 36 is disposed around the O-ring 35 and bonded to the O-ring 35.

  When the probe 10 includes the vibrator 22, the resin member 9 is in contact with the outer periphery of the fixture 36.

  In this way, the vibrator 21 is held by the holder 33 in contact with the holder 33 with the minimum contact area, and the vibrator 22 is held by the O-ring 35 in contact with the O-ring 35 with the minimum contact area. .

  When the probe 10 includes the vibrator 21 or the vibrator 22, the vibrator 21 or the vibrator 22 is held by three points, and thus vibrates more freely than the vibrator 1. As a result, the Q value when the vibrator 21 or the vibrator 22 resonates is improved, and the Young's modulus of the device under test 30 can be measured more accurately.

  Even when the probe 10 includes the vibrator 21 or the vibrator 22, the probe 10 is manufactured according to steps (a) to (m) shown in FIGS. In step (c), the holder 33 is attached to the vibrator 21 and the fixture 34 is attached to the holder 33, or the O-ring 35 is attached to the vibrator 22 and the fixture 36 is an O-ring. 35. In step (d), the support member 7 is attached to the fixture 34 or the fixture 36. Further, in the step (e), the antennas 4 to 6 are wound only once around the fixture 34 or the fixture 36.

  Even when the probe 10 includes the vibrator 21 or the vibrator 22, it is detected whether or not a defect is formed in the object to be measured 30 by detecting the half width FWHM of the peak having the resonance frequency or the attenuation constant α. May be.

  In addition, when the probe 10 includes the vibrator 21 or the vibrator 22, the vibrator 21 (or the vibrator 22) is caused by the burst wave BWh having a frequency n times the resonance frequency or 1 / n times the resonance frequency. Whether or not a defect is formed in the object to be measured 30 may be detected based on whether or not the vibration frequency is excited and the resonance frequency fosc is detected.

  When it is determined whether or not a defect is formed on the object to be measured 30 by the above-described method using the vibrators 21 and 22, the vibrators 21 and 22 are more likely to vibrate than the vibrator 1. It is possible to accurately determine whether or not the measurement object 30 is formed.

  FIG. 25 is a cross-sectional view illustrating another mounting method of the antennas 4 to 6. Referring to FIG. 25, antennas 4 to 6 may be mounted between O-ring 31 and fixture 32. As a result, the distance between the vibrator 1 and the antennas 4 to 6 is shortened, and the vibrator 1 receives a stronger voltage Vv from the antenna 5 than when the antennas 4 to 6 are mounted on the outer periphery of the fixture 32. It becomes easier to vibrate. Further, the antenna 6 receives the polarization electric field generated as the vibrator 1 vibrates as a stronger voltage. Accordingly, the Young's modulus of the device under test 30 can be measured more accurately. Further, it can be determined more accurately whether or not a defect is formed in the DUT 30.

  When the probe 10 includes the vibrator 21, the antennas 4 to 6 may be mounted between the holder 33 and the fixture 34. When the probe 10 includes the vibrator 22, the antennas 4 to 6 are The O-ring 35 and the fixture 36 may be mounted. As a result, more free vibration of the vibrator 21 or the vibrator 22 can be secured, and the polarization electric field generated when the vibrator 21 or the vibrator 22 vibrates can be received as a stronger voltage. The Young's modulus of the object 30 can be measured more accurately. Further, it can be determined more accurately whether or not a defect is formed in the DUT 30.

  FIG. 26 is a cross-sectional view illustrating a method for holding the vibrator 1. 26A, when measuring the Young's modulus of the DUT 30 using the fundamental mode of vibration of the vibrator 1, the O-ring 31 is the length of the vibrator 1 having the length L. In the direction, the vibrator 1 is attached to the vibrator 1 at a position L / 2 from one end of the vibrator 1 (a position corresponding to a node portion in the fundamental mode of vibration of the vibrator 1). That is, the O-ring 31 is attached to a substantially central portion of the vibrator 1 in the length direction of the vibrator 1.

  Referring to FIG. 26B, when measuring the Young's modulus of the DUT 30 using the secondary mode of vibration of the vibrator 1, two O-rings 31 </ b> A and 31 </ b> B are attached to the vibrator 1. . Each of the O-rings 31A and 31B is made of nitrile rubber. The O-ring 31A is located at a position L / 4 from the one end of the vibrator 1 in the length direction of the vibrator 1 having the length L (a position corresponding to a node in the secondary mode of vibration of the vibrator 1). ) And the O-ring 31B corresponds to a position of L / 4 from the other end of the vibrator 1 in the length direction of the vibrator 1 (corresponding to a node portion in the secondary mode of vibration of the vibrator 1). Is mounted on the vibrator 1 at a position where

  Even when the vibrator 21 or the vibrator 22 is used, the vibrator 21 or the vibrator 22 is located at a position substantially L / 4 from the center or the end in the length direction of the vibrator 21 or the vibrator 22. Retained.

  As described above, in the embodiment of the present invention, the Young's modulus of the DUT 30 is measured using either the fundamental mode or the secondary mode of vibration of the vibrators 1, 21, 22. In the embodiment of the present invention, whether or not a defect is formed in the object to be measured 30 by the above-described method using either the fundamental mode or the secondary mode of the vibration of the vibrators 1, 2, and 22. Is detected.

  FIG. 27 is a cross-sectional view showing another method for holding the vibrator 1. Referring to FIG. 27A, notches 101 are formed at four corners of a planar shape (= square) orthogonal to the length direction of the vibrator 1 at a position L / 2 from one end of the vibrator 1. . The notch 101 has an arcuate cross-sectional shape.

  When the vibrator 1 is held by the O-ring 31, the O-ring 31 is attached to the vibrator 1 so that the O-ring 31 fits into the notch 101 (see FIG. 27B).

  When the vibrator 1 is supported by the O-rings 31A and 31B, notches are formed at the four corners of the vibrator 1 at a position L / 4 from one end of the vibrator 1 and a position L / 4 from the other end of the vibrator 1. 101 is provided, and the O-rings 31A and 31B are attached to the vibrator 1 so that the O-rings 31A and 31B are fitted in the notch 101. The same applies when the vibrator 22 is supported by an O-ring.

  Thereby, when the Young's modulus of the object to be measured 30 is measured using the probe 10 or when the defect is detected using the probe 10, the movement of the vibrators 1 and 22 in the length direction can be accurately suppressed.

  FIG. 28 is a diagram showing the relationship between the measurement depth and the radius of the tip. In FIG. 28, the vertical axis represents the measurement depth, and the horizontal axis represents the radius of the chip. The measurement depth is the depth of the measured object 30 to which the vibration is propagated when the chip 2 is brought into contact with the measured object 30 and the vibration of the vibrator 1 is excited by the burst waves BW1 and BW2 (or the burst wave BWh). It is. The radius of the tip is the radius of the original sphere when a spherical tungsten carbide is polished to produce an arc-shaped tip.

  A curve k5 shows the relationship between the measurement depth and the tip radius when the bias force applied to the device under test 30 (= acrylic resin) is 0.5 N, and the curve k6 shows the device under test 30 (= The relationship between the measurement depth and the tip radius when the bias force applied to (copper) is 0.5 N is shown. Note that the relationship between the measurement depth indicated by the curves k5 and k6 and the radius of the tip is calculated.

  Referring to FIG. 28, when the bias force applied to device under test 30 is constant, the measurement depth increases as the radius of the tip increases (see curves k5 and k6).

  Therefore, when an object of a material different from the object to be measured 30 is in contact with the object to be measured 30 on the side opposite to the surface of the object to be measured 30 with which the tip 2 of the probe 10 is brought into contact, the measurement depth of the object to be measured 30 is The radius of the chip is determined so as to be equal to or less than the thickness, and the chip 2 having the determined radius is manufactured and bonded to the end face of the vibrator 1.

  As a result, the Young's modulus of the device under test 30 itself can be measured by eliminating the influence of the object in contact with the device under test 30. Further, it is possible to detect the defect of the object to be measured 30 by eliminating the influence of the object in contact with the object to be measured 30. Further, it is possible to detect the attenuation of vibration of the object to be measured 30 itself by eliminating the influence of the object in contact with the object to be measured 30.

  Although the relationship between the measurement depth and the chip radius shown in FIG. 28 is just an example, the measurement depth of a material other than acrylic resin and copper also increases as the chip radius increases. Accordingly, if the relationship between the measurement depth and the tip radius is calculated in advance for various types of objects to be measured 30, an appropriate tip radius can be determined according to each object to be measured 30.

  In the embodiment of the present invention, the tip radius is set in the range of 0.5 mm to 10 mm, and the tip radius appropriate for the object to be measured 30 is determined from the range of 0.5 mm to 10 mm. 2 is produced.

  FIG. 29 is a cross-sectional view showing an example in which a plurality of chips are mounted on a vibrator. Referring to FIG. 29, each of chips 2A and 2B is made of the same material as chip 2 described above. The radius of the chip 2A is larger than the radius of the chip 2B. The chip 2A is bonded to the end face of one end of the vibrator 1, and the chip 2B is bonded to the end face of the other end of the vibrator 1.

  When using the vibrator 1 to which the chips 2A and 2B are bonded, after the chip 2A is brought into contact with the object to be measured 30 and the Young's modulus of the object to be measured 30 is measured, the chip 2B can contact the object to be measured 30. In this manner, the vibrator 1 is held again by the holding member 3, and the Young's modulus of the device under test 30 is measured by bringing the chip 2 </ b> B into contact with the device under test 30.

  Thus, the Young's modulus and the like of two objects to be measured 30 having different thicknesses can be measured using the same vibrator 1. Further, the distribution of Young's modulus in the depth direction of one object to be measured 30 can be measured using the same vibrator 1.

  FIG. 30 is a cross-sectional view showing the configuration of another probe according to the embodiment of the present invention. The probe according to the embodiment of the present invention may be a probe 10A shown in FIG.

  Referring to FIG. 30, probe 10 </ b> A is obtained by adding needle 17 to probe 10 shown in FIG. 1, and the rest is the same as probe 10.

  The needle 17 is fixed to the bottom surface 11 </ b> A of the case 11. Three or more needles 17 are provided in the bottom surface 11 </ b> A of the case 11. This is because if at least three needles 17 are provided, the probe 10 </ b> A can be stably disposed on the object to be measured 30.

  The diameter of the needle 17 is set to a diameter at which the needle 17 enters the device under test 30 when the probe 10 </ b> A is arranged on the device under test 30.

  The length of the needle 17 is set to such a length that the bottom surface 11A of the case 11 of the probe 10A can contact the device under test 30 when the surface of the device under test 30 is a flat surface. Further, the length of the needle 17 is set to a length at which the tip of the needle 17 enters the device under test 30 when the device under test 30 has a spherical shape.

  As described above, when the probe 10A is used, the tip 2 can stably come into contact with the object to be measured 30, and the Young's modulus or the like of the object to be measured 30 can be accurately measured.

  The other description of the probe 10A is the same as the description of the probe 10.

  FIG. 31 is a conceptual diagram showing an application example of the probe 10 shown in FIG. Referring to FIG. 31, the mouse 60 of the personal computer incorporates a position measuring device 70. The probe 10 is mounted in the mouse 60.

  The position measuring device 70 measures the position of the mouse 60 based on the principle of a laser mouse, and outputs the measured position to a CPU (Central Processing Unit) of the personal computer.

  The antenna 5 of the probe 10 is connected to a voltage source 40, and the antenna 6 is connected to a CPU of a personal computer.

  The mouse 60 is disposed on the device under test 30 and is moved to each position of the device under test 30. Then, the position measuring instrument 70 measures the position of the mouse 60 and outputs the measured position to the CPU of the personal computer. Further, the vibrator 1 of the probe 10 vibrates by the voltage Vv applied from the voltage source 40 via the antenna 5, and the antenna 6 receives as a voltage the polarization electric field generated when the vibrator 1 vibrates. The received voltage (reception signal) is output to the CPU of the personal computer.

  Then, the CPU of the personal computer calculates the Young's modulus of the device under test 30 by the method described above based on the received signal received from the antenna 6, and the mouse 60 receiving the calculated Young's modulus from the position measuring device 70. It is stored in the memory in association with the position. The CPU of the personal computer stores the Young's modulus at each position of the DUT 30 in the memory in association with each position of the mouse 60.

  Accordingly, the Young's modulus distribution of the device under test 30 can be measured.

  Even when the probe 10 is placed in the mouse 60, the defect of the object to be measured 30 may be measured by the various methods described above, or the non-destructive inspection of the object to be measured 30 may be performed by the method described above. Good.

  As described above, the vibrators 1, 2, 22 are held by the O-rings 31, 35 or the holder 33 with a minimum contact area at positions corresponding to the vibration nodes of the vibrators 1, 2, 22. Further, the vibrators 1, 2, and 22 apply a bias force to the object to be measured 30 by the repulsive force RF generated by the magnets 8 and 13 having the same polarity. As a result, the vibrators 1, 2, 22 freely vibrate, and even if the device under test 30 is arranged at an arbitrary angle with respect to the vertical direction, the bias applied to the device under test 30. The force becomes constant.

  Therefore, stable vibrations of the vibrators 1, 2, 22 can be secured, and an elastic constant can be measured by applying a bias force to the device under test 30 from an arbitrary direction.

  In the embodiment of the present invention, each of the O-rings 31 and 35 constitutes a “holding tool”. In the embodiment of the present invention, magnet 8 constitutes a “first magnet”, and magnet 13 constitutes a “second magnet”. Further, the antenna 4 constitutes a “first antenna”, the antenna 5 constitutes a “second antenna”, and the antenna 6 constitutes a “third antenna”. Furthermore, the detector 50 that determines whether or not the resonance frequency of the vibrator 1 is detected based on the received voltage received from the antenna 6 constitutes a “determination device”.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention is applied to a probe and a measuring apparatus including the probe.

Claims (11)

A vibrator having a rod-like shape and made of a piezoelectric body;
A chip bonded to one end of the vibrator on the measured object side and having a hardness higher than that of the measured object;
A holder that contacts the vibrator with a minimum contact area in the circumferential direction of the vibrator and holds a part of the vibrator corresponding to a vibration node of the vibrator;
A first magnet disposed on the other end side of the vibrator and bonded to a support member that supports the holder;
A second magnet disposed at a desired distance from the first magnet in the longitudinal direction of the vibrator, and having the same polarity as the first magnet;
A first antenna connected to ground potential;
A second antenna for applying an excitation voltage for exciting vibration of the vibrator to the vibrator in cooperation with the first antenna;
A third antenna that receives the electric field generated in the vibrator due to the excitation voltage being applied to the vibrator as a voltage in cooperation with the first antenna;
The first to third antennas are arranged in the vicinity of a part of the vibrator,
The probe has a circular arc shape protruding in a direction from the vibrator toward the object to be measured. A case for housing the vibrator, the chip, the first magnet, and the holder;
Filled between the vibrator, the first magnet and the holder and the case, and can be moved in the length direction of the vibrator together with the vibrator, the chip, the first magnet and the holder. And further comprising a resin member,
The one end of the vibrator and the chip protrude outward from the opening of the case when the chip is not in contact with the object to be measured.
The vibrator, the chip, the first magnet, the holder, and the resin member are moved from the first magnet to the second as the end of the case comes into contact with the object to be measured. The probe according to claim 1, which moves in the direction of the magnet.   The probe according to claim 1, wherein the holder is made of a ring-shaped nitrile rubber.   The probe according to claim 3, wherein the tip is made of tungsten carbide. A case for housing the vibrator, the chip, the first magnet, and the holder;
Filled between the vibrator, the first magnet and the holder and the case, and can be moved in the length direction of the vibrator together with the vibrator, the chip, the first magnet and the holder. And further comprising a resin member,
The one end of the vibrator and the chip protrude outward from the opening of the case when the chip is not in contact with the object to be measured.
The vibrator, the chip, the first magnet, the holder, and the resin member are moved from the first magnet to the second as the end of the case comes into contact with the object to be measured. The probe according to claim 4, which moves in the direction of the magnet. A case for housing the vibrator, the chip, the first magnet, and the holder;
Filled between the vibrator, the first magnet and the holder and the case, and can be moved in the length direction of the vibrator together with the vibrator, the chip, the first magnet and the holder. And further comprising a resin member,
The one end of the vibrator and the chip protrude outward from the opening of the case when the chip is not in contact with the object to be measured.
The vibrator, the chip, the first magnet, the holder, and the resin member are moved from the first magnet to the second as the end of the case comes into contact with the object to be measured. The probe according to claim 3, which moves in the direction of the magnet.   The probe according to claim 1, wherein the tip is made of tungsten carbide. A case for housing the vibrator, the chip, the first magnet, and the holder;
Filled between the vibrator, the first magnet and the holder and the case, and can be moved in the length direction of the vibrator together with the vibrator, the chip, the first magnet and the holder. And further comprising a resin member,
The one end of the vibrator and the chip protrude outward from the opening of the case when the chip is not in contact with the object to be measured.
The vibrator, the chip, the first magnet, the holder, and the resin member are moved from the first magnet to the second as the end of the case comes into contact with the object to be measured. The probe according to claim 7, which moves in the direction of the magnet. A probe according to claim 1;
A voltage source for outputting the excitation voltage to the second antenna;
And a detector that detects a resonance frequency of the vibrator based on the received voltage received by the third antenna and calculates a Young's modulus of the device to be measured based on the detected resonance frequency. A probe according to claim 1;
A voltage source for outputting the excitation voltage to the second antenna;
A half-width of a peak having a resonance frequency of the vibrator is detected based on a received voltage received by the third antenna, or the vibrator is attenuated based on a received voltage received by the third antenna. And a detector for detecting an attenuation constant when performing the measurement. A probe according to claim 1;
A voltage having a frequency obtained by multiplying the resonance frequency of the vibrator by n (n is an integer of 2 or more) or a frequency obtained by multiplying the resonance frequency of the vibrator by 1 / n is output as the excitation voltage to the second antenna. A voltage source;
And a determination device that determines whether or not a resonance frequency of the vibrator is detected based on a reception voltage received by the third antenna.

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