WO2017085863A1 - Dispositif de mesure, procédé de mesure et programme informatique - Google Patents

Dispositif de mesure, procédé de mesure et programme informatique Download PDF

Info

Publication number
WO2017085863A1
WO2017085863A1 PCT/JP2015/082691 JP2015082691W WO2017085863A1 WO 2017085863 A1 WO2017085863 A1 WO 2017085863A1 JP 2015082691 W JP2015082691 W JP 2015082691W WO 2017085863 A1 WO2017085863 A1 WO 2017085863A1
Authority
WO
WIPO (PCT)
Prior art keywords
terahertz wave
sample
angle
irradiation
refractive index
Prior art date
Application number
PCT/JP2015/082691
Other languages
English (en)
Japanese (ja)
Inventor
義行 奧田
Original Assignee
パイオニア株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by パイオニア株式会社 filed Critical パイオニア株式会社
Priority to JP2017551490A priority Critical patent/JP6538191B2/ja
Priority to PCT/JP2015/082691 priority patent/WO2017085863A1/fr
Publication of WO2017085863A1 publication Critical patent/WO2017085863A1/fr

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
    • G01N21/3581—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light using far infrared light; using Terahertz radiation
    • G01N21/3586—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light using far infrared light; using Terahertz radiation by Terahertz time domain spectroscopy [THz-TDS]
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length

Definitions

  • the present invention relates to a technical field of a measuring apparatus, a measuring method, and a computer program for measuring a refractive index of a sample using, for example, a terahertz wave.
  • a measuring device using a terahertz wave is known as a measuring device for measuring the refractive index of a sample.
  • a sample is irradiated with a terahertz wave through a transmission member that is in contact with the sample, and based on the time waveform of the terahertz wave reflected by the transmission member and the time waveform of the terahertz wave reflected by the sample.
  • An information acquisition device for acquiring the refractive index of a sample is described.
  • Patent Document 2 discloses that a terahertz wave is irradiated on a specimen disposed between a reflecting member and a plate-like member through the plate-like member and reflected at the interface between the plate-like member and the specimen.
  • An information acquisition device is described that acquires the refractive index of a specimen based on the time waveform of the wave and the time waveform of the terahertz wave reflected at the interface between the specimen and the reflecting member.
  • JP 2014-209094 A Japanese Patent Laying-Open No. 2015-83964
  • the terahertz wave irradiated on the surface of the sample reaches the back surface of the sample located on the opposite side of the surface by passing through the inside of the sample, and then Acquisition means for acquiring the transmission time required to reach the surface again by being reflected by the back surface for each of a plurality of irradiation angles of the terahertz waves having different angles with respect to the surface, the transmission time, and the transmission time Calculating means for calculating a refractive index of the sample based on a plurality of irradiation angles.
  • the terahertz wave irradiated on the surface of the sample passes through the inside of the sample and reaches the back surface of the sample located on the opposite side of the surface.
  • An acquisition step of acquiring the transmission time required to reach the surface again by being reflected by the back surface for each of a plurality of irradiation angles of the terahertz waves having different angles with respect to the surface, the transmission time, and the transmission time And a calculation step of calculating a refractive index of the sample based on a plurality of irradiation angles.
  • the first example of the computer program of the present invention causes a computer to execute the first example of the measurement method of the present invention described above.
  • FIG. 1 is a block diagram illustrating a configuration of the terahertz wave measuring apparatus according to the present embodiment.
  • FIG. 2 is a flowchart showing an example of the flow of measurement operation for measuring the refractive index and thickness performed by the terahertz wave measuring apparatus.
  • FIG. 3 is a plan view showing an example of the irradiation angle changing operation.
  • FIG. 4 is a cross-sectional view of the sample showing the optical path of the terahertz wave irradiated on the sample and the optical path of the terahertz wave reflected by the sample.
  • FIG. 5 is a graph showing a waveform signal of the terahertz wave detected by the terahertz wave detecting element.
  • FIG. 6 is a cross-sectional view of the sample showing the optical path of the terahertz wave irradiated to the sample and the optical path of the terahertz wave reflected by the sample.
  • the terahertz wave irradiated on the surface of the sample passes through the inside of the sample, reaches the back surface of the sample located on the opposite side of the surface, and is then reflected by the back surface.
  • the acquisition means for acquiring the transmission time required to reach the surface again for each of the plurality of irradiation angles of the terahertz waves having different angles with respect to the surface
  • calculating means for calculating the refractive index of the sample.
  • a plurality of transmission times and a plurality of times corresponding to a plurality of irradiation angles can be obtained without bringing any special member into contact with the sample.
  • the refractive index of the sample can be suitably measured (that is, calculated).
  • the acquisition unit has the transmission time when the irradiation angle is the first angle, and the irradiation angle is a second angle different from the first angle. Get the transmission time of the case.
  • the measurement apparatus can suitably measure the refractive index of the sample if it acquires two transmission times respectively corresponding to two irradiation angles.
  • the measuring device does not have to acquire three or more transmission times corresponding to three or more irradiation angles in order to measure the refractive index of the sample.
  • the first angle is defined as ⁇ 1
  • the transmission time when the irradiation angle is the first angle is defined as Delta] t 1
  • the transmission time when the irradiation angle is the second angle Delta] t the variable a is defined by Equation 1 and the refractive index is defined by n
  • the calculating unit calculates the refractive index based on Equation 2.
  • the measurement apparatus can appropriately measure the refractive index of the sample based on the transmission time and the irradiation angle by performing the calculation based on the mathematical formulas 1 and 2.
  • the acquisition unit includes a first time required for the terahertz wave irradiated on the surface to reach a predetermined position after being reflected on the surface, and the surface A second time required to reach the predetermined position after the terahertz wave irradiated on the back surface is reflected on the back surface is acquired for each of the plurality of irradiation angles, and the transmission time is the second time and the second time The difference from the first time.
  • the measuring apparatus can preferably measure the refractive index of the sample based on the first and second times (or the transmission time that can be calculated from the first and second times) and the irradiation angle. it can.
  • an irradiation unit that irradiates the terahertz wave toward the surface, and a detection unit that detects the terahertz wave reflected by the sample.
  • the predetermined position is a position where the detection means is installed, and the terahertz wave reflected on the surface after the irradiation means irradiates the terahertz wave after the irradiation means irradiates the terahertz wave for the first time.
  • the time required to reach the detection means, and the second time is the time required for the terahertz wave reflected from the back surface to reach the detection means after the irradiation means irradiates the terahertz wave. It is.
  • the measuring apparatus can suitably measure the refractive index of the sample using the irradiation unit and the detection unit.
  • the acquisition unit is configured to determine the first and second times when the irradiation angle is the first angle and the irradiation angle.
  • the first and second times when the second angle is different from the first angle are acquired, the first angle is defined as ⁇ 1 , the second angle is defined as ⁇ 2, and the irradiation angle Are defined as t a1 and t b1, respectively, and the first and second times when the irradiation angle is the second angle are t a2, respectively.
  • t b2 the variable a is defined by Expression 3
  • the refractive index is defined as n
  • the calculation means calculates the refractive index based on Expression 4.
  • the measurement device performs the calculation based on the mathematical formulas 3 and 4, and thus based on the first and second times (or the transmission time that can be calculated from the first and second times) and the irradiation angle.
  • the refractive index of the sample can be suitably measured.
  • the measurement apparatus further includes a changing unit that changes the irradiation angle.
  • the measuring apparatus can preferably acquire the transmission time for each of a plurality of irradiation angles having different angles.
  • the calculation unit further calculates the thickness of the sample, which is a physical distance between the front surface and the back surface, based on the calculated refractive index. .
  • the measuring apparatus can measure (that is, calculate) the thickness of the sample in addition to the refractive index.
  • the terahertz wave irradiated on the surface of the sample passes through the inside of the sample, reaches the back surface of the sample located on the opposite side of the surface, and is then reflected by the back surface. And acquiring the transmission time required to reach the surface again for each of a plurality of irradiation angles of the terahertz waves having different angles with respect to the surface, and based on the transmission time and the plurality of irradiation angles And calculating a refractive index of the sample.
  • the measurement device of the present embodiment it is possible to suitably enjoy the same effects as those that can be enjoyed by the measurement device of the present embodiment described above.
  • the measurement method of this embodiment may adopt various aspects.
  • the computer program of this embodiment causes a computer to execute the measurement method of this embodiment described above.
  • the computer program of the present embodiment may adopt various aspects.
  • the computer program may be recorded on a computer-readable recording medium.
  • the measurement apparatus includes an acquisition unit and a calculation unit.
  • the measurement method of this embodiment includes an acquisition process and a calculation process.
  • the computer program of this embodiment causes a computer to execute the measurement method of this embodiment described above. Therefore, the refractive index of the sample is measured even when no special member is brought into contact with the sample.
  • the measurement apparatus the measurement method, and the computer program are described using an example in which the measurement apparatus, the measurement method, and the computer program are applied to the terahertz wave measurement apparatus 100 that measures the refractive index n of the sample 10 by irradiating the sample 10 with the terahertz wave THz. To proceed.
  • FIG. 1 is a block diagram illustrating a configuration of a terahertz wave measuring apparatus 100 according to the present embodiment.
  • the terahertz wave measuring apparatus 100 irradiates the sample 10 with the terahertz wave THz, and detects the terahertz wave THz reflected by the sample 10 (that is, the terahertz wave THz irradiated on the sample 10).
  • the terahertz region is a frequency region that combines light straightness and electromagnetic wave transparency.
  • the terahertz region is a frequency region in which various substances have unique absorption spectra. Therefore, the terahertz wave measuring apparatus 100 can measure the characteristics of the sample 10 by analyzing the terahertz wave THz irradiated on the sample 10.
  • the terahertz wave measuring apparatus 100 can measure the refractive index n of the sample 10 which is an example of the characteristics of the sample 10 by analyzing the terahertz wave THz irradiated on the sample 10.
  • the terahertz wave measuring apparatus 100 indirectly detects the waveform of the terahertz wave THz by employing a pump-probe method based on time delay scanning.
  • a pump-probe method based on time delay scanning.
  • the terahertz wave measuring apparatus 100 includes a pulse laser apparatus 101, a terahertz wave generating element 110 which is a specific example of “irradiation means”, a beam splitter 161, a reflecting mirror 162, and a reflecting mirror 163.
  • the pulse laser device 101 generates sub-picosecond order or femtosecond order pulse laser light LB having a light intensity corresponding to the drive current input to the pulse laser device 101.
  • the pulse laser beam LB generated by the pulse laser device 101 is incident on the beam splitter 161 via a light guide (not shown) (for example, an optical fiber).
  • the beam splitter 161 branches the pulsed laser light LB into pump light LB1 and probe light LB2.
  • the pump light LB1 is incident on the terahertz wave generating element 110 through a light guide path (not shown).
  • the probe light LB2 enters the optical delay mechanism 120 via a light guide path and a reflecting mirror 162 (not shown). Thereafter, the probe light LB2 emitted from the optical delay mechanism 120 is incident on the terahertz wave detection element 130 via the reflecting mirror 163 and a light guide path (not shown).
  • the terahertz wave generating element 110 emits a terahertz wave THz.
  • the terahertz wave generating element 110 includes a pair of electrode layers facing each other through a gap.
  • a bias voltage generated by the bias voltage generation unit 141 is applied to the gap via a pair of electrode layers.
  • an effective bias voltage for example, a bias voltage other than 0 V
  • the pump light LB1 is also applied to the photoconductive layer formed below the gap. Is irradiated. In this case, carriers are generated in the photoconductive layer irradiated with the pump light LB1 by light excitation by the pump light LB1.
  • the terahertz wave generating element 110 generates a pulse-shaped current signal in the order of subpicoseconds or in the order of femtoseconds corresponding to the generated carrier.
  • the generated current signal flows through the pair of electrode layers.
  • the terahertz wave generating element 110 emits the terahertz wave THz resulting from the pulsed current signal.
  • the terahertz wave THz emitted from the terahertz wave generating element 110 passes through the half mirror 164.
  • the terahertz wave THz transmitted through the half mirror 164 is irradiated to the sample 10 (particularly, the surface 10a of the sample 10).
  • the terahertz wave THz irradiated on the sample 10 is reflected by the sample 10 (particularly, by the front surface 10a and the back surface 10b of the sample).
  • the terahertz wave THz reflected by the sample 10 is reflected by the half mirror 164.
  • the terahertz wave THz reflected by the half mirror 164 enters the terahertz wave detection element 130.
  • the terahertz wave detecting element 130 detects the terahertz wave THz incident on the terahertz wave detecting element 130.
  • the terahertz wave detection element 130 includes a pair of electrode layers facing each other with a gap interposed therebetween.
  • the probe light LB2 is irradiated to the gap
  • the probe light LB2 is also irradiated to the photoconductive layer formed below the gap.
  • carriers are generated in the photoconductive layer irradiated with the probe light LB2 by light excitation by the probe light LB2.
  • a current signal corresponding to the carrier flows through the pair of electrode layers included in the terahertz wave detection element 130.
  • the signal intensity of the current signal flowing through the pair of electrode layers changes according to the light intensity of the terahertz wave THz.
  • a current signal whose signal intensity changes according to the light intensity of the terahertz wave THz is output to the IV conversion unit 142 via the pair of electrode layers.
  • the optical delay mechanism 120 adjusts the difference (that is, the optical path length difference) between the optical path length of the pump light LB1 and the optical path length of the probe light LB2. Specifically, the optical delay mechanism 120 adjusts the optical path length difference by adjusting the optical path length of the probe light LB2.
  • the timing at which the pump light LB1 enters the terahertz wave generation element 110 (or the timing at which the terahertz wave generation element 110 emits the terahertz wave THz) and the probe light LB2 at the terahertz wave detection element 130
  • the time difference from the timing at which the light enters (or the timing at which the terahertz wave detecting element 130 detects the terahertz wave THz) is adjusted.
  • the terahertz wave measuring apparatus 100 indirectly detects the waveform of the terahertz wave THz by adjusting the time difference.
  • the timing at which the probe light LB2 enters the terahertz wave detection element 130 is delayed by 1 picosecond.
  • the timing at which the terahertz wave detecting element 130 detects the terahertz wave THz is delayed by 1 picosecond.
  • the timing at which the terahertz wave detecting element 130 detects the terahertz wave THz is gradually shifted.
  • the terahertz wave detection element 130 can indirectly detect the waveform of the terahertz wave THz. That is, the lock-in detection unit 151 described later can detect the waveform of the terahertz wave THz based on the detection result of the terahertz wave detection element 130.
  • the current signal output from the terahertz wave detection element 130 is converted into a voltage signal by the IV conversion unit 142.
  • the control unit 150 performs a control operation for controlling the entire operation of the terahertz wave measuring apparatus 100.
  • the control unit 150 includes a CPU (Central Processing Unit) and a memory.
  • the memory stores a computer program for causing the control unit 150 to perform a control operation.
  • a logical processing block for performing a control operation is formed inside the CPU.
  • the computer program may not be recorded in the memory. In this case, the CPU may execute a computer program downloaded via a network.
  • the control unit 150 performs a measurement operation for measuring the characteristics of the sample 10 based on the detection result of the terahertz wave detection element 130 (that is, the voltage signal output from the IV conversion unit 142).
  • the control unit 150 includes a lock-in detection unit 151 and a signal processing unit 152 as logical processing blocks formed in the CPU.
  • the lock-in detection unit 151 performs synchronous detection on the voltage signal output from the IV conversion unit 142 using the bias voltage generated by the bias voltage generation unit 141 as a reference signal. As a result, the lock-in detection unit 151 detects a sample value of the terahertz wave THz. Thereafter, the same operation is repeated while appropriately adjusting the difference between the optical path length of the pump light LB1 and the optical path length of the probe light LB2 (that is, the optical path length difference).
  • the waveform (time waveform) of the terahertz wave THz detected by the detection element 130 can be detected.
  • the lock-in detection unit 151 outputs a waveform signal indicating the waveform of the terahertz wave THz detected by the terahertz wave detection element 130 to the signal processing unit 152. That is, the lock-in detection unit 151 removes a noise component having a frequency different from that of the reference signal from the voltage signal output from the IV conversion unit 142 (that is, the detection signal of the terahertz wave THz). That is, the lock mark detection unit 151 detects the time waveform signal with relatively high sensitivity and relatively high accuracy by performing synchronous detection using the detection signal and the reference signal. If the terahertz wave measuring apparatus 100 does not use lock-in detection, a DC voltage may be applied to the terahertz wave generating element 110 as a bias voltage.
  • the signal processing unit 152 measures the characteristics of the sample 10 based on the waveform signal output from the lock-in detection unit 151. For example, the signal processing unit 152 acquires the frequency spectrum of the terahertz wave THz using terahertz time domain spectroscopy, and measures the characteristics of the sample 10 based on the frequency spectrum.
  • the signal processing unit 152 performs a measurement operation of measuring the refractive index n of the sample 10 based on the waveform signal output from the lock-in detection unit 151 as an example of the control operation. Further, as an example of the control operation, the signal processing unit 152 is based on the waveform signal output from the lock-in detection unit 151, and the thickness d of the sample 10 (that is, the direction in which the terahertz wave THz is incident on the sample 10). A measurement operation for measuring the thickness d) along the line is performed.
  • the thickness d means “physical distance between the front surface 10a and the back surface 10b”.
  • the signal processing unit 152 includes a detection time acquisition unit 1521 that is a specific example of the “acquisition unit” and a “calculation unit” as logical processing blocks formed inside the CPU.
  • a refractive index calculation unit 1522 as a specific example and a thickness calculation unit 1523 as a specific example of “calculation means” are provided. Note that specific examples of operations of the detection time acquisition unit 1521, the refractive index calculation unit 1522, and the thickness calculation unit 1523 will be described in detail later and will not be described here.
  • the control unit 150 further includes an irradiation angle changing unit 153 as a logical processing block formed inside the CPU.
  • the irradiation angle changing unit 153 controls the terahertz wave generating element 110 so as to change the irradiation angle (typically, the incident angle) ⁇ of the terahertz wave THz with respect to the sample 10.
  • the irradiation angle ⁇ changes, the emission angle of the terahertz wave THz reflected from the sample 10 from the sample 10 also changes.
  • the irradiation angle changing unit 153 that controls the terahertz wave generating element 110 to change the irradiation angle ⁇ is reflected by the sample 10 when the terahertz wave generating element 110 is controlled to change the irradiation angle ⁇ .
  • the terahertz wave detecting element 130 is controlled so that the terahertz wave detecting element 130 appropriately detects the terahertz wave THz.
  • FIG. 2 is a flowchart illustrating an example of a flow of a measurement operation for measuring the refractive index n and the thickness d performed by the terahertz wave measuring apparatus 100.
  • the irradiation angle changing unit 153 controls the terahertz wave generating element 110 so that the irradiation angle ⁇ becomes “ ⁇ 1 ”, which is a specific example of “first angle” (step S101). ). Further, the irradiation angle changing unit 153 also controls the terahertz wave detecting element 130 so that the terahertz detecting element 130 appropriately detects the terahertz wave THz irradiated at the irradiation angle ⁇ 1 (step 101).
  • FIG. 3 is a plan view showing an example of the operation of changing the irradiation angle ⁇ .
  • the terahertz wave measuring apparatus 100 includes an actuator 171, a guide rail 172, an actuator 173, and a guide rail 174 in order to change the irradiation angle ⁇ .
  • the actuator 171 controls the terahertz wave generating element 110 and the optical element 111 that guides the terahertz wave THz emitted from the terahertz wave generating element 110 to the surface of the sample 10 along the guide rail 173 under the control of the irradiation angle changing unit 153.
  • the irradiation angle changing unit 153 changes (in other words, adjusts) the irradiation angle ⁇ by controlling (for example, adjusting) the moving direction and the moving amount of the terahertz wave generating element 110 and the optical element 111.
  • the actuator 173 moves the optical element 131 that guides the terahertz wave detection element 130 and the terahertz wave THz reflected by the sample 10 to the terahertz wave detection element 130 along the guide rail 174 under the control of the irradiation angle changing unit 153.
  • the irradiation angle changing unit 153 is capable of appropriately detecting the terahertz wave THz reflected by the sample 10 by controlling (for example, adjusting) the moving direction and moving amount of the terahertz wave detecting element 130 and the optical element 131.
  • the terahertz wave detecting element 130 can be moved to the position.
  • the irradiation angle changing unit 153 changes the irradiation angle ⁇ from “ ⁇ 1 ” to “ ⁇ 2 (where ⁇ 2 ⁇ ⁇ 1 )”.
  • the emission angle of the terahertz wave THz reflected by the sample 10 with respect to the surface 10a of the sample 10 is also changed from “ ⁇ 1 ” to “ ⁇ 2 ”.
  • the irradiation angle changing unit 153 emits the terahertz wave detection element 130 from the sample 10 at the emission angle ⁇ 2 from the detection position where the terahertz wave THz emitted from the sample 10 at the emission angle ⁇ 1 can be detected.
  • the terahertz wave THz is moved to a detectable position.
  • the terahertz wave measuring apparatus 100 may change the irradiation angle ⁇ by an operation different from the changing operation shown in FIG.
  • the terahertz wave generating element 110 emits the terahertz wave THz toward the surface 10a of the sample 10 (step S102). That is, the terahertz wave generating element 110, a terahertz wave THz irradiating the surface 10a of the sample 10 at an irradiation angle theta 1 (step S102).
  • FIG. 4 is a cross-sectional view of the sample 10 showing the optical path of the terahertz wave THz irradiated on the sample 10 and the optical path of the terahertz wave THz reflected by the sample 10.
  • a part of the terahertz wave THz irradiated on the sample 10 at the irradiation angle ⁇ 1 is reflected by the surface 10 a of the sample 10.
  • a part of the terahertz wave THz irradiated to the sample 10 at the irradiation angle ⁇ 1 is transmitted through the sample 10 without being reflected by the surface 10a. Thereafter, the terahertz wave THz transmitted through the sample 10 reaches the back surface 10 b of the sample 10. As a result, a part of the terahertz wave THz transmitted through the sample 10 is reflected by the back surface 10 b of the sample 10. The terahertz wave THz reflected by the back surface 10b passes through the sample 10 again. Thereafter, the terahertz wave THz transmitted through the sample 10 reaches the surface 10 a of the sample 10. As a result, some of the terahertz wave THz reflected by the rear surface 10b, so as to emit from the sample 10 at the emission angle theta 1, propagates to the terahertz wave detecting element 130 from the sample 10.
  • the front surface 10a and the back surface 10b are the two outer surfaces of the sample 10 that face each other along the propagation direction of the terahertz wave THz in the sample 10 (the horizontal direction in FIGS. 1 and 4).
  • the surface 10a corresponds to one outer surface close to the terahertz wave generating element 110 and the terahertz wave detecting element 130 among the two outer surfaces.
  • the back surface 10b corresponds to the other outer surface far from the terahertz wave generating element 110 and the terahertz wave detecting element 130 out of the two outer surfaces.
  • a reflecting member may be arranged so as to be in contact with or in close contact with the back surface 10b of the sample 10.
  • the terahertz wave THz reflected by the sample 10 is detected by the terahertz wave detecting element 130 (step S102).
  • a waveform signal indicating the waveform of the terahertz wave THz detected by the terahertz wave detecting element 130 is input to the signal processing unit 152.
  • the detection time acquisition unit 1521 acquires the first detection time t a1 and the second detection time t b1 based on the waveform signal input to the signal processing unit 152 (step S103). That is, the terahertz wave measuring apparatus 100 based on the detection result of the irradiation at an angle theta 1 terahertz wave THz, to obtain a first detection time t a1 and the second detection time t b1.
  • the detection time acquisition unit 1521 outputs the first detection time t a1 and the second detection time t b1 acquired when the terahertz wave THz is irradiated at the irradiation angle ⁇ 1 to the refractive index calculation unit 1522.
  • the first detection time t a1 and the second detection time t b1 are specific examples of “first time” and “second time”, respectively.
  • FIG. 5 is a graph showing a waveform signal of the terahertz wave THz detected by the terahertz wave detecting element 130.
  • the waveform signal includes a waveform signal corresponding to the terahertz wave THz reflected by the front surface 10a and a waveform signal corresponding to the terahertz wave THz reflected by the back surface 10b.
  • the terahertz wave THz reflected by the back surface 10b reaches the terahertz wave detecting element 130 after passing through the inside of the sample 10, while the terahertz wave THz reflected by the front surface 10a does not pass through the inside of the sample 10 and does not pass through the terahertz wave.
  • the wave detection element 130 is reached.
  • the terahertz wave THz reflected by the back surface 10b reaches the terahertz wave detecting element 130 later in time than the terahertz wave THz reflected by the front surface 10a. Therefore, also on the waveform signal, the waveform signal corresponding to the terahertz wave THz reflected by the back surface 10b is delayed in time from the waveform signal corresponding to the terahertz wave THz reflected by the front surface 10a.
  • the first detection time ta1 is a time required for the terahertz wave THz reflected from the surface 10a of the sample 10 to reach the terahertz wave detecting element 130 after the terahertz wave generating element 110 starts irradiation with the terahertz wave THz. is there.
  • the second detection time t b1 is from when the terahertz wave generating element 110 starts irradiation of the terahertz wave THz until the terahertz wave THz reflected by the back surface 10b of the sample 10 reaches the terahertz wave detecting element 130. It takes time.
  • the detection time acquisition unit 1521 can easily acquire (in other words, calculate or specify) the first detection time t a1 and the second detection time t b1 by analyzing the waveform signal.
  • the terahertz wave measuring apparatus 100 performs the above-described operation (that is, the operation for acquiring the first detection time t a2 and the second detection time t b2 ) again after changing the irradiation angle ⁇ .
  • the irradiation angle changing unit 153 includes the terahertz wave generating element 110 so that the irradiation angle ⁇ is different from “ ⁇ 1 ” and becomes “ ⁇ 2 ” which is a specific example of “second angle”. Is controlled (step S111).
  • the irradiation angle changing unit 153 also controls the terahertz wave detecting element 130 so that the terahertz detecting element 130 appropriately detects the terahertz wave THz irradiated at the irradiation angle ⁇ 2 (step 111). Then, the terahertz wave generating element 110, a terahertz wave THz irradiating the surface 10a of the sample 10 at an irradiation angle theta 1 (step S112). Thereafter, the terahertz wave detecting element 130 detects the terahertz wave THz reflected by the sample 10 (step S112).
  • a waveform signal indicating the waveform of the terahertz wave THz detected by the terahertz wave detecting element 130 is input to the signal processing unit 152.
  • the detection time acquisition unit 1521 acquires the first detection time t a2 and the second detection time t b2 based on the waveform signal input to the signal processing unit 152 (step S113). That is, the terahertz wave measuring apparatus 100 based on the detection result of the irradiation at an angle theta 2 terahertz wave THz, to obtain a first detection time t a2 and the second detection time t b2.
  • the detection time acquisition unit 1521 outputs the first detection time t a2 and the second detection time t b2 acquired when the terahertz wave THz is irradiated at the irradiation angle ⁇ 2 to the refractive index calculation unit 1522.
  • the first detection time t a2 and the second detection time t b2 are specific examples of “first time” and “second time”, respectively.
  • the refractive index n of the sample 10 is calculated (step S121). Specifically, the refractive index calculation unit 1522 calculates the refractive index n using Equation 5. Note that the variable a in Equation 5 is defined by Equation 6. ⁇ t 1 in Expression 6 corresponds to the time required for the terahertz wave THz to pass through the inside of the sample 10 when the terahertz wave THz is irradiated at the irradiation angle ⁇ 1 .
  • ⁇ t 1 in Equation 6 is the time required for the terahertz wave THz to reach the surface 10 a again from the front surface 10 a of the sample 10 through the back surface 10 b when the terahertz wave THz is irradiated at the irradiation angle ⁇ 1.
  • Equivalent to. ⁇ t 2 in Expression 6 corresponds to the time required for the terahertz wave THz to pass through the inside of the sample 10 when the terahertz wave THz is irradiated at the irradiation angle ⁇ 2 .
  • ⁇ t 2 in Equation 6 is the time required for the terahertz wave THz to reach the surface 10a again from the front surface 10a of the sample 10 via the back surface 10b when the terahertz wave THz is irradiated at the irradiation angle ⁇ 2.
  • Equivalent to. ⁇ t 1 and ⁇ t 2 are specific examples of the transmission time.
  • FIG. 6 is a cross-sectional view of the sample 10 showing the optical path of the terahertz wave THz irradiated on the sample 10 and the optical path of the terahertz wave THz reflected by the sample 10.
  • the terahertz wave THz irradiated on the surface 10a of the sample 10 at the irradiation angle ⁇ 1 enters (propagates) into the sample 10 at the refraction angle ⁇ 1 ′.
  • Equation 7 can be expanded as shown in Equation 8.
  • Equation 9 is satisfied.
  • Equation 10 is solved for n, Equation 5 described above is obtained.
  • the thickness calculator 1523 obtains the first detection time t a1 and the second detection time t b1 (more specifically, the first detection time t a1 and the second detection time t b1. Based on ⁇ t 1 ), the refractive index n, and the irradiation angle ⁇ 1 , the thickness d of the sample 10 is calculated (step S122). Specifically, the thickness calculation unit 1523 calculates the thickness d of the sample 10 using Formula 11 obtained by solving Formula 8 for d.
  • the thickness calculation unit 1523 performs the first detection time t a2 and the second detection time t b2 (more specifically, ⁇ t 2 obtained from the first detection time t a2 and the second detection time t b2 ), refraction.
  • the thickness d of the sample 10 may be calculated based on the rate n and the irradiation angle ⁇ 2 (step S122).
  • the thickness calculation unit 1523 may calculate the thickness d of the sample 10 using Formula 12 obtained by solving Formula 9 for d instead of Formula 11.
  • the terahertz measurement apparatus 100 of the present embodiment can suitably measure (that is, calculate) the refractive index n of the sample 10.
  • the terahertz measurement apparatus 100 according to the present embodiment suitably irradiates the sample 10 with the terahertz wave THz at a plurality of different irradiation angles ⁇ , so that the refractive index n is suitably set without bringing any special member into contact with the sample 10. It can be measured.
  • the terahertz measuring apparatus 100 of the present embodiment can suitably measure the refractive index n, the thickness d of the sample 10 can also be favorably measured.
  • the sample 10 is irradiated with the terahertz wave THz after setting the irradiation angle ⁇ to zero.
  • a terahertz wave measuring device is assumed.
  • the terahertz wave measuring apparatus of the comparative example to obtain a first detection time t a and the second detection time t b.
  • the terahertz wave measuring apparatus 100 of the comparative example needs to measure the refractive index n in order to measure the original thickness d.
  • the measurement of the refractive index n is generally troublesome.
  • the terahertz wave measuring apparatus 100 of the present embodiment has a great advantage that the refractive index n can be measured relatively easily.
  • the numerical formula 5 mentioned above is a numerical formula obtained by solving simultaneous equations (namely, simultaneous equations consisting of two equations having d and n as unknowns) composed of numerical formulas 8 to 9 with respect to n. .
  • the terahertz wave measuring apparatus 100 may calculate the refractive index n by solving simultaneous equations composed of Expressions 8 to 9 for n instead of using Expression 5.
  • the terahertz wave measuring apparatus 100 determines whether the simultaneous equations are satisfied by substituting the assumed values of n into the simultaneous equations, and adjusts the assumed values of n that are substituted into the simultaneous equations until the simultaneous equations are satisfied. The operation may be repeated. In this case, an assumed value of n that satisfies the simultaneous equations corresponds to the refractive index n of the sample 10.
  • the present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification.
  • a measurement method and a computer program are also included in the technical scope of the present invention.

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Health & Medical Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Toxicology (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

La présente invention concerne un dispositif de mesure (100) qui est équipé d'un moyen d'acquisition (1 521) qui, pour chaque angle parmi une pluralité d'angles d'exposition à un rayonnement d'ondes térahertz θ1, θ2, dont les angles diffèrent par rapport à une surface (10a) d'un spécimen (10), acquiert des périodes de transmission Δt1, Δt2 qui sont nécessaires pour qu'une onde térahertz THz émise vers la surface (10a) du spécimen (10) atteigne la surface arrière (10b) du spécimen en passant par l'intérieur du spécimen, et atteigne ensuite de nouveau la surface du spécimen après avoir été réfléchie par ladite surface arrière. Le dispositif de mesure (100) est en outre équipé d'un moyen de calcul (1 522) permettant de calculer l'indice de réfraction n du spécimen sur la base des périodes de transmission et des angles d'exposition à un rayonnement.
PCT/JP2015/082691 2015-11-20 2015-11-20 Dispositif de mesure, procédé de mesure et programme informatique WO2017085863A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2017551490A JP6538191B2 (ja) 2015-11-20 2015-11-20 計測装置、計測方法及びコンピュータプログラム
PCT/JP2015/082691 WO2017085863A1 (fr) 2015-11-20 2015-11-20 Dispositif de mesure, procédé de mesure et programme informatique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2015/082691 WO2017085863A1 (fr) 2015-11-20 2015-11-20 Dispositif de mesure, procédé de mesure et programme informatique

Publications (1)

Publication Number Publication Date
WO2017085863A1 true WO2017085863A1 (fr) 2017-05-26

Family

ID=58719202

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2015/082691 WO2017085863A1 (fr) 2015-11-20 2015-11-20 Dispositif de mesure, procédé de mesure et programme informatique

Country Status (2)

Country Link
JP (1) JP6538191B2 (fr)
WO (1) WO2017085863A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109188105A (zh) * 2018-10-19 2019-01-11 北京环境特性研究所 适用于太赫兹频段高反射材料介电参数测量装置及方法
CN109211843A (zh) * 2018-10-19 2019-01-15 北京环境特性研究所 一种太赫兹波反射测量***入射角确定方法及装置
CN109239015A (zh) * 2018-10-19 2019-01-18 北京环境特性研究所 一种太赫兹波段反射弓形架装置

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102285056B1 (ko) * 2019-10-31 2021-08-04 주식회사 마인즈아이 테라헤르츠파 분광기술 기반 계측시스템

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030025899A1 (en) * 2001-06-18 2003-02-06 Amara Mohamed Kamel Method and apparatus for simultaneous measurement of the refractive index and thickness of thin films
JP2009210422A (ja) * 2008-03-04 2009-09-17 Sony Corp プローブ装置及びテラヘルツ分光装置
WO2010106589A1 (fr) * 2009-03-18 2010-09-23 株式会社村田製作所 Instrument de mesure optique et procédé de mesure optique
JP2011252872A (ja) * 2010-06-04 2011-12-15 Nec Corp 反射型イメージング装置
JP2012237657A (ja) * 2011-05-12 2012-12-06 Advantest Corp 電磁波測定装置、測定方法、プログラム、記録媒体
JP2013181929A (ja) * 2012-03-04 2013-09-12 Canon Inc 測定装置及び方法、トモグラフィ装置及び方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030025899A1 (en) * 2001-06-18 2003-02-06 Amara Mohamed Kamel Method and apparatus for simultaneous measurement of the refractive index and thickness of thin films
JP2009210422A (ja) * 2008-03-04 2009-09-17 Sony Corp プローブ装置及びテラヘルツ分光装置
WO2010106589A1 (fr) * 2009-03-18 2010-09-23 株式会社村田製作所 Instrument de mesure optique et procédé de mesure optique
JP2011252872A (ja) * 2010-06-04 2011-12-15 Nec Corp 反射型イメージング装置
JP2012237657A (ja) * 2011-05-12 2012-12-06 Advantest Corp 電磁波測定装置、測定方法、プログラム、記録媒体
JP2013181929A (ja) * 2012-03-04 2013-09-12 Canon Inc 測定装置及び方法、トモグラフィ装置及び方法

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109188105A (zh) * 2018-10-19 2019-01-11 北京环境特性研究所 适用于太赫兹频段高反射材料介电参数测量装置及方法
CN109211843A (zh) * 2018-10-19 2019-01-15 北京环境特性研究所 一种太赫兹波反射测量***入射角确定方法及装置
CN109239015A (zh) * 2018-10-19 2019-01-18 北京环境特性研究所 一种太赫兹波段反射弓形架装置
CN109188105B (zh) * 2018-10-19 2020-10-13 北京环境特性研究所 适用于太赫兹频段高反射材料介电参数测量装置及方法
CN109211843B (zh) * 2018-10-19 2021-03-16 北京环境特性研究所 一种太赫兹波反射测量***入射角确定方法及装置
CN109239015B (zh) * 2018-10-19 2024-02-06 北京环境特性研究所 一种太赫兹波段反射弓形架装置

Also Published As

Publication number Publication date
JPWO2017085863A1 (ja) 2018-09-06
JP6538191B2 (ja) 2019-07-03

Similar Documents

Publication Publication Date Title
JP5489906B2 (ja) テラヘルツ波トランシーバ及び断層像取得装置
WO2017085863A1 (fr) Dispositif de mesure, procédé de mesure et programme informatique
JP6945001B2 (ja) 検査装置、検査方法、ライブラリ生成装置、ライブラリ生成方法、コンピュータプログラム及び記録媒体
JP6692914B2 (ja) 検査装置、検査方法、コンピュータプログラム及び記録媒体
US9134182B2 (en) Measurement apparatus and method, tomography apparatus and method
CN109883337A (zh) 基于太赫兹光谱技术的热障涂层厚度测量***和测量方法
WO2016132452A1 (fr) Dispositif de mesure d'ondes térahertz, procédé de mesure d'ondes térahertz, et programme informatique
JP6754446B2 (ja) 検査装置、検査方法、コンピュータプログラム及び記録媒体
JP2014106127A (ja) テラヘルツ波計測装置及び方法
US20180266967A1 (en) Optical test apparatus
WO2017085862A1 (fr) Dispositif de mesure, procédé de mesure et programme informatique
WO2018066359A1 (fr) Dispositif d'examen, procédé d'examen, programme d'ordinateur et support d'enregistrement
US11867567B2 (en) Thermo-physical property measurement instrument and thermo-physical property measurement method
JP6913261B2 (ja) 計測装置、計測方法及びコンピュータプログラム
WO2017138061A1 (fr) Dispositif de mesure
JP6614620B2 (ja) 計測装置、計測方法及びコンピュータプログラム
JP2004128113A (ja) 半導体キャリアの寿命測定方法及びその装置
JP2019203905A (ja) 計測装置、計測方法及びコンピュータプログラム
JP5256136B2 (ja) 電磁波測定装置、及び電磁波測定方法
JP4873489B2 (ja) 薄膜熱物性測定装置
US20160010978A1 (en) Measurement apparatus and measuring method
JP2017142087A (ja) 計測装置、計測方法及びコンピュータプログラム
JP6331133B2 (ja) 膜厚計測装置と方法
JP2004251766A (ja) 温度測定方法およびそれに用いる測定装置
WO2018066361A1 (fr) Dispositif d'examen, procédé d'examen, programme informatique et support d'enregistrement

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15908803

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2017551490

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15908803

Country of ref document: EP

Kind code of ref document: A1