WO2002060017A1 - Élément générant de la lumière térahertzienne, générateur et détecteur de lumière térahertzienne - Google Patents

Élément générant de la lumière térahertzienne, générateur et détecteur de lumière térahertzienne Download PDF

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Publication number
WO2002060017A1
WO2002060017A1 PCT/JP2002/000591 JP0200591W WO02060017A1 WO 2002060017 A1 WO2002060017 A1 WO 2002060017A1 JP 0200591 W JP0200591 W JP 0200591W WO 02060017 A1 WO02060017 A1 WO 02060017A1
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Prior art keywords
terahertz
terahertz light
light
substrate
conductive films
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PCT/JP2002/000591
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English (en)
Japanese (ja)
Inventor
Hiromichi Akahori
Ryoichi Fukasawa
Mamoru Usami
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Nikon Corporation
Tochigi Nikon Corporation
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Priority claimed from JP2001018544A external-priority patent/JP2002223017A/ja
Priority claimed from JP2001170318A external-priority patent/JP2002368250A/ja
Application filed by Nikon Corporation, Tochigi Nikon Corporation filed Critical Nikon Corporation
Publication of WO2002060017A1 publication Critical patent/WO2002060017A1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S1/00—Masers, i.e. devices using stimulated emission of electromagnetic radiation in the microwave range
    • H01S1/02—Masers, i.e. devices using stimulated emission of electromagnetic radiation in the microwave range solid
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/08—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors

Definitions

  • the present invention relates to a terahertz light generation element and a terahertz light generation device using an optical switch element.
  • Electromagnetic waves with frequencies between 0.1 and 10 TH are called terahertz light, and research on application fields using terahertz light is being actively pursued.
  • terahertz light generation device and a detection device is underway.
  • Auston and Smith invented the optical switching device (D. H. Auston K. P. Cheung and P. R. Smith
  • FIG. 22 schematically shows an example of a conventional terahertz optical device 1 using an optical switch device. It is a schematic perspective view shown in FIG. FIG. 23 is a schematic cross-sectional view of the terahertz optical element 1 shown in FIG. 22 along the line xxm.
  • This conventional terahertz optical element 1 is composed of a GaAs substrate 2, a low-temperature grown GaAs film 3 as a photoconductive film formed on the substrate 2, and two GaAs films formed on the film 3.
  • Metal films 4 and 5 as conductive films are provided.
  • the metal films 4 and 5 are separated from each other on the film 3, and have transmission line portions 4a and 5a forming parallel transmission lines, and electrode portions formed at both ends of the transmission line portions 4a and 5a. 4b, 4c, 5b, and 5c.
  • the central portions of the transmission line sections 4a and 5a protrude inward (the sides where the metal films 4 and 5 face each other).
  • the protruding portions of the transmission line portions 4a and 5a have a minute interval d (for example, an interval of several / xm) in the direction along the surface of the substrate 1.
  • An optical switch element is formed by the vicinity of the distance d. Further, a portion near the distance d in the transmission line portions 4a and 5a forms a dipole antenna.
  • a case where the terahertz light element 1 is used as a terahertz light generation element will be described with reference to FIG.
  • a DC power supply or a pulse power supply 10 is connected between the electrode portions 4b and 5b.
  • a DC bias voltage is applied from the DC power supply or the pulse power supply 10 between the electrode sections 4b and 5b, and an irradiation section including a laser light source (not shown) separates one femtosecond pulse laser beam from the film 3 side. Irradiated near d. As a result, free carriers are generated in the film 3 and a current flows, and a terahertz pulse light is generated by the pulsed current.
  • the generated terahertz pulse light passes through the substrate 2 and is generated radially mainly on the side opposite to the film 3 as shown in FIG. Since the output of terahertz light is at most sub-millimeter at the maximum, to maximize the use of the generated terahertz light, as shown in Fig. 24, a collection of high-resistance silicon A plano-convex lens 11 for light is arranged.
  • the generated terahertz pulse light passes through the substrate 2 and is collected by the lens 11 as shown by the arrow 10.0 in FIG.
  • the collected terahertz pulse light is used by a predetermined optical system (not shown) or the like.
  • the lens 11 is usually brought into close contact with the back surface of the substrate 2 by a jig.
  • a jig for example, an air layer 12 is interposed between the substrate 2 and the lens 11.
  • the generated terahertz pulsed light passed through the boundary 13 between the substrate 2 and the air layer 12 and the boundary 14 between the air layer 12 and the lens 11 Later, the light is emitted outside through the lens 11.
  • a terahertz light element 1 is used as a terahertz light detection element
  • An ammeter 15 for detecting a current flowing between the electrodes 4b and 5b is connected.
  • a femtosecond pulsed laser beam is applied from the side of the film 3 to the vicinity of the interval d by an irradiation unit (not shown)
  • free carriers are contained in the film 3. (Electrons and holes) are generated, and a current that is approximately proportional to the magnitude of the electric field of the incident terahertz pulse light flows at this time.
  • a terahertz light detection signal is obtained.
  • a plano-convex lens 16 made of high-resistance silicon for focusing is arranged behind the substrate 2 as shown in FIG.
  • the terahertz pulse light to be detected is condensed by the lens 16 as shown by the arrow 101 in FIG. 25 and is condensed near the distance d after passing through the substrate 2 .
  • Lens 16 is usually closely attached to the back of substrate 2.
  • an air layer is interposed between the substrate 2 and the lens 16. Therefore, the terahertz pulse light to be detected reaches the vicinity of the distance d via the boundary between the lens 16 and the air layer and the boundary between the air layer and the substrate 2.
  • the terahertz light emitted from the terahertz light generator shown in FIG. 24 passes through an optical system suitable for each application for each of various uses, and then passes through the terahertz light shown in FIG. Light is incident on the photodetector.
  • the output of the terahertz light of the terahertz light generator is about a submilliwatt at most, so the optical system using the terahertz light is the terahertz light element 1 and the lenses 11, 16. It is necessary that the loss of terahertz light is small, including that of terahertz. Therefore, for example, the lenses 11 and 16 are made of a material having a high transmittance to terahertz pulsed light. However, in the case of using a conventional terahertz light element using an optical switch element, the loss of the terahertz light could not be reduced sufficiently.
  • the terahertz pulse light generated by the terahertz optical element 1 forms the boundary 13 between the substrate 2 and the air layer 12 and the boundary 14 between the air layer 12 and the lens 11 as described above. As a result, losses occur at these two boundaries 13 and 14, respectively.
  • the refractive index of the substrate 2 for the terahertz light used is nl
  • the refractive index of the air layer is n2
  • the refractive index of the lens 11 is n3
  • the boundaries 13 and 1 are shown.
  • the substrate 2 is composed of G a As (the refractive index for terahertz light having a frequency of 1 THz is 3.6).
  • the loss of the terahertz light is large. Disclosure of the invention
  • An object of the present invention is to provide a terahertz light element capable of reducing the loss of terahertz light, a terahertz light generation device and a terahertz light detection device using the same.
  • a terahertz light element generates or detects terahertz light, and includes: a base material; a photoconductive film formed on a predetermined surface of the base material; and a photoconductive film formed on the photoconductive film. And two conductive films separated from each other, and at least some of the two conductive films are arranged so as to be spaced apart from each other in a direction along a predetermined plane. At least a portion of the substrate is exposed to at least one of terahertz light emitted from the substrate to the opposite side of the photoconductive film and / or terahertz light incident to the substrate from the opposite side of the photoconductive film. It is formed so as to act as a lens.
  • the above-described lens action is a convex lens action, and the terahertz light entering the base material from the side opposite to the photoconductive film is emitted near the portion between at least some of the two conductive films in the photoconductive film. It is desirable to have a condensing lens function of condensing light.
  • the substrate is composed of Si, Ge, GaAs or sapphire. Further, it is desirable that the photoconductive film is made of low-temperature grown GaAs or ion-implanted silicon.
  • the above-described terahertz light element can be applied to a terahertz light generator. That is, the above-described terahertz optical element, an irradiation section that irradiates a predetermined portion of the terahertz optical element with excitation pulse light from the side opposite to the substrate, and a voltage application section that applies a bias voltage between the two conductive films.
  • the terahertz light generation device according to the present invention can be configured.
  • the above-described terahertz light element can be applied to a terahertz light detection device. That is, the above-described terahertz optical element, and a base material at a predetermined position of the terahertz optical element
  • the terahertz light detection device according to the present invention can be configured using an irradiation unit that irradiates the excitation pulse light from the opposite side and a current detection unit that detects a current flowing between the two conductive films.
  • the terahertz light generation device includes the above-described terahertz light element, an irradiation section that irradiates a predetermined portion of the terahertz light element with excitation pulse light, and applies a bias voltage between two conductive sections. And a voltage application unit, and a capacitor can be electrically connected between the two conductive units. As a result, noise generated due to the generation of terahertz light can be reduced.
  • FIG. 1 is a schematic perspective view schematically showing a terahertz optical element according to a first embodiment of the present invention.
  • FIG. 2 is a schematic cross-sectional view of the terahertz optical element shown in FIG.
  • FIG. 3 is a schematic plan view schematically showing a pattern of a conductive film on the photoconductive film in FIG.
  • FIG. 4 is a diagram schematically showing a state in which terahertz light passes through the terahertz light element shown in FIG.
  • FIG. 5 is a schematic perspective view schematically showing a terahertz light generation device according to a second embodiment of the present invention.
  • FIG. 6 is a schematic perspective view schematically showing a terahertz light detection device according to a third embodiment of the present invention.
  • FIG. 7 is a schematic plan view schematically showing another example of the pattern of the conductive film on the photoconductive film.
  • FIG. 8 is a schematic plan view schematically showing still another example of the pattern of the conductive film on the photoconductive film.
  • FIG. 9 is a schematic plan view schematically showing still another example of the pattern of the conductive film on the photoconductive film.
  • FIG. 10 is a schematic plan view schematically showing still another example of the pattern of the conductive film on the photoconductive film.
  • FIG. 11 is a schematic configuration diagram showing a terahertz light generation device according to a fourth embodiment of the present invention.
  • FIG. 12 is a diagram showing a terahertz light generation element used in the terahertz light generation device shown in FIG.
  • FIG. 13 is a schematic sectional view showing another example of the terahertz light generation element.
  • FIG. 14 is an explanatory diagram schematically showing the state of charges in the terahertz light generation element.
  • FIG. 15 is a diagram showing the configuration of the device used in the experiment.
  • FIG. 16 is a diagram showing the waveform of the voltage change observed in the experiment.
  • FIG. 17 is a schematic sectional view showing a terahertz light generating element used in the terahertz light generating device according to the fifth embodiment of the present invention.
  • FIG. 18 is a diagram showing a terahertz light generation element used in the terahertz light generation device according to the sixth embodiment of the present invention.
  • FIG. 19 is a schematic perspective view showing a terahertz light generation element used in the terahertz light generation device according to the seventh embodiment of the present invention.
  • FIG. 20 is a schematic perspective view showing a terahertz light generation element used in the terahertz light generation device according to the eighth embodiment of the present invention.
  • FIG. 21 is a diagram in which a capacitor is added between the conductive films of the terahertz light generator shown in FIG.
  • FIG. 22 is a schematic perspective view schematically showing an example of a conventional terahertz optical element.
  • FIG. 23 is a schematic cross-sectional view of the conventional terahertz optical element shown in FIG. 22 along the line XXm-xxm.
  • FIG. 24 is a schematic perspective view schematically showing an example in which the terahertz light element shown in FIG. 22 is used as a terahertz light generation element.
  • FIG. 25 is a schematic perspective view schematically showing an example in which the terahertz light element shown in FIG. 22 is used as a terahertz light detection element.
  • FIG. 26 schematically shows how terahertz light passes in the example shown in Fig. 24.
  • FIG. 1 is a schematic perspective view schematically showing a terahertz optical element 21 according to the first embodiment of the present invention.
  • FIG. 2 is a schematic cross-sectional view of the terahertz optical element 21 shown in FIG.
  • FIG. 3 is a schematic plan view schematically showing the pattern of the conductive films 24 and 25 on the photoconductive film 23 in FIG. Fig. 3 shows an example of the irradiation area R, R 'of a single femtosecond pulse laser beam. Note that FIG. 3 shows two irradiation regions R and R ′, and one of the irradiation regions is irradiated with one femtosecond pulse laser beam.
  • the terahertz light element 21 generates or detects terahertz light.
  • the base 22 and the upper side of the base 22 (the upper and lower sides are indicated by the upper and lower sides in FIG. 2). It includes a photoconductive film 23 formed on a flat surface, and two conductive films 24 and 25 formed on the photoconductive film 23 and separated from each other. At least some of the conductive films 24 and 25 are arranged so as to have a predetermined interval d in a direction along a plane above the base material 22.
  • At least a part of the base material 22 includes a terahertz light TL1 emitted from the base material 22 to the side opposite to the photoconductive film 23 and a terahertz light TL1 incident on the base material 22 from the opposite side to the photoconductive film 23.
  • the light TL 2 is formed to have a lens function. Note that the photoconductive film 23 does not necessarily need to be interposed between the conductive film 24 and the base material 22 over the entire region of the conductive films 24 and 25.
  • the base material 22 for example, Si, .Ge, GaAs, or sapphire can be used.
  • a material of the photoconductive film 23 for example, low-temperature grown GaAs or ion-implanted silicon (RD-SOS) can be used. RD-SOS is also disclosed in the above-mentioned paper by Smith et al. (IEEE Journal of Quantum Electronics, Vol. 24, No. 2, pp. 255-260 (1988)). You.
  • the conductive film 25 for example, a metal film such as A1 or Au can be used.
  • the conductive films 24 and 25 are formed at transmission line portions 24 a and 25 a forming parallel transmission lines and at both ends thereof. Electrode portions 24 b, 24 c 25 b, and 25 c.
  • the central portion of the transmission line portions 24a and 25a protrudes inward (on the side where the conductive films 24 and 25 face each other), and a small distance d in the direction along the upper plane of the base material 22 between them. It is open.
  • the interval d is, for example, about several im.
  • An optical switch element is constituted by a portion near the interval d. A portion near the distance d in the transmission line sections 24a and 25a forms a dipole antenna.
  • the base material 22 has a circular flat surface on the upper surface and a convex spherical surface on the lower surface.
  • the substrate 22 is formed to be a plano-convex lens, similarly to the lens 11 shown in FIG. 24 and the lens 16 shown in FIG. 25 described above.
  • the central axis O of the terahertz optical element 21 passes near the center of the interval d as shown in FIGS.
  • the terahertz light TL 2 incident on the substrate 22 from the side opposite to the photoconductive film 23 is applied to the conductive films 24, 25 in the photoconductive film 23.
  • the curvature and the like of the lower surface of the base material 22 are determined so that light is condensed in the vicinity of a portion between the portions. In the present invention, it is not always necessary to set such a curvature.
  • a substrate 22 previously formed into a plano-convex lens shape by optical polishing or the like is prepared.
  • the lenses 11 and 16 used in the above-described conventional technology can be used, or a commercially available product can be purchased. .
  • the surface of the prepared substrate 22 other than the upper plane is covered with a jig (not shown), the substrate 22 is supported by the jig, and the photoconductive film 2 is formed on the upper plane by a film forming technique. 3 is formed.
  • the film forming technique may be any of epitaxy growth, vapor deposition, sputtering, CVD, and any other method. What is necessary is just to select and adopt according to the material of the conductive film 23.
  • a method for forming a low-temperature-grown GaAs is well known, and a method for forming a RD-SOS film is also described in the above-mentioned paper by Smith et al. (IEEE Journal of Quan tum Electronics, Vol. 24, No. 2). , pp. 255-260 (1988)).
  • a conductive film is formed on the photoconductive film 23 by an evaporation method, an epitaxial growth, or the like, and the conductive film is patterned by photolithography. , 25 are formed.
  • the terahertz optical element 21 By the method described above, the terahertz optical element 21 according to the present embodiment is completed.
  • the method for manufacturing the terahertz optical element 21 is not limited to the above-described example. The effects of this embodiment will be described later in connection with the second and third embodiments described later.
  • FIG. 5 is a schematic perspective view schematically showing a terahertz light generation device according to a second embodiment of the present invention.
  • the terahertz light generator includes a terahertz light element 21 according to the first embodiment, an irradiation unit 31 for irradiating a femtosecond pulse laser beam, and a terahertz light element 21.
  • a DC power supply or a pulse power supply 32 is provided as a voltage application unit for applying a DC bias voltage between the electrode units 24 b and 25 b.
  • the terahertz light element 21 is used as a terahertz light generation element.
  • the irradiation unit 31 includes, for example, a laser light source, and a lens that adjusts the size of the irradiation area as needed.
  • the femtosecond pulsed laser beam is irradiated from the side opposite to the substrate 22 (that is, the side of the photoconductive film 23) toward the irradiation region R or R 'of the terahertz optical element 21 shown in FIG. Is done.
  • a DC bias voltage is applied from the DC power supply or the pulse power supply 32 between the electrode portions 24 b and 25 b.
  • a free carrier is generated in the photoconductive film 23 and a current flows.
  • Terahertz pulse light is generated by this pulsed current, and is generated radially mainly on the substrate 22 side.
  • the generated TE The lahertz pulse light is condensed by a base material 22 acting as a convex lens as indicated by an arrow 102 shown in FIG. 5, and is used by a predetermined optical system (not shown) or the like. Since the light is converged by the base material 22 as described above, the generated terahertz pulse light is used to the maximum extent.
  • the boundaries 13 and 14 do not exist unlike the above-described conventional technology. Therefore, the generated terahertz pulse light does not pass through two boundaries with the air layer corresponding to boundaries 13 and 14 in FIG. That is, as schematically shown in FIG. 4, the generated terahertz pulse light directly enters the base material 22, passes through and is emitted to the outside.
  • the loss of the terahertz pulsed light (52.6% energy loss in the above-described calculation example) caused by the boundaries 13 and 14 in the above-described conventional technology does not occur.
  • the loss of the terahertz pulse light can be significantly reduced as compared with the above-described related art.
  • the terahertz light generating element 21 is an integrated structure in which the base material 22 also functions as the lens 11 shown in FIG. There is no need for troublesome positioning of the lens 1 and the lens 11.
  • FIG. 6 is a schematic perspective view schematically showing a terahertz light detection device according to a third embodiment of the present invention.
  • the terahertz light detection device includes a terahertz light element 21 according to the first embodiment, an irradiation unit 41 that irradiates a femtosecond pulse laser beam, and a terahertz light element 2.
  • An ammeter 42 is provided as a current detector for detecting a current flowing between the first electrode portions 24 b and 25 b.
  • the terahertz light element 21 is used as a terahertz light detection element.
  • the irradiating unit 41 emits a femtosecond pulsed laser beam that irradiates, for example, a terahertz light generating element (the terahertz light element 21 in FIG. 5 in the above-described second embodiment).
  • An optical system (not shown) that guides the pulsed light obtained by splitting the light after delaying (for synchronization) by a predetermined variable time.
  • Femtosecond pal Similarly to the second embodiment, the laser beam is directed toward the irradiation region R or R ′ in FIG. 3 of the terahertz optical element 21 on the side opposite to the substrate 22 (that is, the photoconductive film). 2 3 side).
  • free carriers are generated in the photoconductive film 23 by the irradiation of one femtosecond pulse laser beam, and the electric field of the terahertz pulse light incident at this time is large.
  • a current almost proportional to the current flows.
  • a terahertz light detection signal is obtained.
  • the terahertz pulse light to be detected is condensed by the substrate 22 acting as a convex lens, and condensed near the interval d. In this way, by condensing the terahertz pulse light, the detection sensitivity of the terahertz pulse light can be improved.
  • the boundaries 13 and 14 do not exist unlike the above-described conventional technology. Therefore, the terahertz pulse light to be detected arrives near the distance d without passing through the two boundaries with the air layer corresponding to boundaries 13 and 14 shown in Fig. 26. Therefore, the loss of the terahertz pulse light caused by the boundaries 13 and 14 in the above-described conventional technology does not occur. For this reason, according to the present embodiment, the loss of the terahertz pulse light can be significantly reduced as compared with the above-described conventional technology. That is, the detection sensitivity of the terahertz pulse light is further improved.
  • the terahertz light generating element 21 is an integrated structure in which the base material 22 also functions as the lens 16 in FIG. There is no need for troublesome positioning between the lens 1 and the lens 16.
  • the pattern of the conductive films 24 and 25 on the photoconductive film 23 in the terahertz optical element 21 is not limited to the pattern of the above-described embodiment.
  • the patterns shown in FIGS. 7 to 10 are schematic plan views schematically showing examples of the patterns of the conductive films 24 and 25 on the photoconductive film 23, and correspond to FIG. 7 to 10 also show examples of the irradiation region R of the femtosecond pulsed laser light.
  • the conductive film 24 is connected to the positive electrode of the DC power supply or the pulse power supply 32.
  • FIG. 7 shows an example in which the dipole antenna is formed not on the center but on one side.
  • the interval dl in FIG. 7 is, for example, about several meters.
  • FIG. 8 shows an example in which a stripline is used as an antenna.
  • the interval d2 in FIG. 8 is, for example, about several tens / im.
  • FIG. 9 shows an example of forming a bow-tie antenna.
  • the interval d3 in FIG. 9 is, for example, about several meters.
  • FIG. 10 shows an example of forming a large-diameter optical switch element as disclosed in the above-mentioned paper (IEEE Journal of Quantum Electronics, Vol. 32, No. 10, PP1839-1846 (1996)). It can be said that the conductive films 24 and 25 have only the electrode portion without having the antenna portion.
  • the interval d4 in FIG. 10 is, for example, about several millimeters to several tens of millimeters.
  • the loss of the terahertz pulse light can be significantly reduced.
  • the terahertz light generation device of the fourth embodiment in addition to the reduction of the loss of the terahertz pulse light, it is possible to reduce the noise caused by the generation of the terahertz light.
  • FIG. 11 is a schematic configuration diagram illustrating a terahertz light generation device according to a fourth embodiment of the present invention.
  • FIG. 12 is a diagram showing the vicinity of the conductive films 24 and 25 of the terahertz light generating element 21a shown in FIG. 11,
  • FIG. 12 (a) is a schematic plan view thereof, and
  • FIG. FIG. 4 is a schematic cross-sectional view of the terahertz light generation element 21a shown in FIG.
  • the terahertz light generation device includes a terahertz light generation element 21a, an irradiation unit 51, a DC power supply 32 as a voltage application unit, and a capacitator. And a capacitor 50.
  • the terahertz light generating element 21a includes a substrate 22 as a photoconductive portion and two separated conductive portions formed on one surface of the substrate 22. And the conductive films 24 and 25 of FIG.
  • the base material 22 is the first to As in the third embodiment, it is formed to form a plano-convex lens.
  • the conductive films 24 and 25 have the same pattern as that shown in FIG. 10 and are arranged with an interval g.
  • the interval g is set to 2 mm or more, for example, 5 mm.
  • the substrate 22 itself is used as a photoconductive portion as described above.
  • a photoconductive film 23 is formed on the substrate 22 as a photoconductive portion.
  • the conductive films 24 and 25 may be formed on the photoconductive film 23.
  • FIG. 13 is a schematic cross-sectional view showing another example of the terahertz light generating element 21a, and corresponds to FIG. 12 (b).
  • the irradiation unit 51 applies an ultra-short pulse of femtosecond pulse laser light to a region R corresponding to the interval g of the terahertz light generating element 21a.
  • a pulse laser is irradiated as excitation pulse light.
  • the capacitor 50 is electrically connected between the conductive films 24 and 25.
  • capacitor 50 is provided separately from DC power supply 32.
  • the capacity of the capacitor 50 is preferably 10 pF or more.
  • the capacitance of the capacitor 50 is more preferably 100 pF or more, more preferably 0.01 F or more, and more preferably 1 or more. More preferably, it is more preferably 100 F or more.
  • the capacitor 50 may be provided in the DC power supply 32, and the capacitor 50 may be included in a power supply circuit constituting the DC power supply 32. In this case, it is preferable that the capacity of the capacitor 50 be equal to or more than 300 pF. In order to further enhance the noise reduction effect, the capacitance of the capacitor 50 is more preferably at least 0.01 F, more preferably at least 0.01 F, more preferably at least 100 F, More preferably, it is not less than 100.
  • a DC voltage is applied between the conductive films 24 and 25 by the DC power supply 32.
  • the resistance value between the two conductive films 24 and 25 is extremely large. Due to the high current, almost no current flows.
  • the irradiating section 51 irradiates the gap portion with an ultrashort pulse laser beam having energy equal to or greater than the band gap of a semiconductor or the like forming the substrate 22. When it is excited by excitation and generates free carriers, the resistance drops and a current flows. Since the pulse width of the pump laser light is sufficiently short and the lifetime of the pump carrier is short, this current flows only for a very short time.
  • an electromagnetic wave is generated because the current changes with time. If the pulse width of the pump laser beam is sufficiently short (for example, less than 100 fs), the frequency of the electromagnetic wave reaches several THz. This is terahertz light. If we look at only a very short time before and after the laser beam irradiation, the current value changes very quickly in time, so such a system can be regarded as a high-frequency circuit.
  • FIGS. 14 (a) to 14 (c) are explanatory diagrams schematically showing the state of charges in the terahertz light generation element 21a.
  • a voltage is applied between the conductive films 24 and 25
  • positive charges holes
  • negative charges electrospray
  • the voltage between the conductive films 24 and 25 is proportional to the amount of accumulated charge.
  • the following equation (4) holds between the power supply voltage VQ applied by the DC power supply 32 and the electric charge Q accumulated in the conductive films 24 and 25.
  • the charge stored in the conductive films 24 and 25 is reduced by the amount consumed as the current, and the voltage between the conductive films 24 and 25 is reduced.
  • the electric charge it is preferable that the electric charge be replenished immediately from the power supply 32, but such is not possible with a normal constant voltage power supply. Therefore, the voltage of the entire circuit fluctuates with time. This voltage fluctuation causes noise.
  • the voltage between the conductive films 24 and 25 of the terahertz light generating element 21a decreases because the electric charge accumulated between the conductive films 24 and 25 decreases. Therefore, if the reduced charge can be quickly replenished, voltage fluctuations can be suppressed and noise can be reduced.
  • a capacitor 50 is electrically connected between the conductive films 24 and 25 as a charge supply source for the conductive films 24 and 25. Even with such a configuration, the voltage drop cannot be completely prevented, but if the total amount of accumulated charge is increased, the ratio of the consumed charge to the total amount is reduced, and the voltage drop is reduced. Can be suppressed.
  • the charge QC is proportional to the voltage applied to the capacitor 50.
  • the proportionality constant is i3
  • the power supply voltage V0 is also applied to the capacitor 50 in a state where no current flows, so that the following equation (6) holds.
  • V2 (Q- q + q C)-(7)
  • qC is the charge supplemented from the capacitor 50 to the conductive films 24, 25.
  • V2 ⁇ ⁇ / ( ⁇ + / 3) ⁇ (Q + QC- q)... (9)
  • Figure 15 shows the configuration of the equipment used in this experiment.
  • the terahertz light generator shown in FIG. 15 is obtained by adding an oscilloscope 60 to the terahertz light generator shown in FIG.
  • the oscilloscope 60 is synchronized with the femtosecond pulse laser light emitted from the irradiation unit 51 to the terahertz light generation element 21a. Specifically, it is possible to observe a time change of a voltage applied between the conductive films 24 and 25 in synchronization with the laser light.
  • An oscilloscope 60 having an input resistance of 50 ⁇ was used.
  • the laser light used as the excitation pulse light is an ultrashort pulse laser light having a center wavelength of 800 nm, a pulse width of about 100 fs, and a repetition frequency of 1 kHz.
  • the power supply voltage of the DC power supply 32 was 30 V.
  • An oscilloscope 60 and a DC power supply 32 were connected in series between the conductive films 24 and 25.
  • the resistance of the terahertz light generating element 1 between the conductive films 24 and 25 is very large (several tens of ⁇ ), so when the ultrashort pulse laser light is not irradiated Most of the power supply voltage of the DC power supply 32 is applied between the conductive films 24 and 25. Irradiation of ultrashort pulse laser light to Terahertz light generator 21a
  • the resistance between the conductive films 24 and 25 of the terahertz light generating element 21a decreases, the voltage applied to the oscilloscope 60 increases. Observe the time change of the voltage at this time.
  • FIGS. 16 (a) and 16 (b) show the waveforms observed with the capacitor 50 removed. Both have different time scales.
  • FIG. 16C shows the waveform observed when the capacitor 50 is electrically connected between the conductive films 24 and 25.
  • the scales of the vertical and horizontal axes in Fig. 16 (a)-16 (c) are as shown in the figure. It should be noted that the scales of the vertical and horizontal axes shown in FIG. 16 (c) are different from the scales shown in FIGS. 16 (a) and 16 (b).
  • a 0.1 F ceramic capacitor was used as the capacitor 50.
  • the change in the voltage is as high as 1.16V, which indicates that it causes noise.
  • the time required for the voltage to return to the steady state is 1 ⁇ s or more.
  • a 0.1 ⁇ F capacitor 50 is electrically connected between the conductive films 24 and 25 (corresponding to the present embodiment), as shown in FIG.
  • the change is around 160mV. That is, the voltage change is about 17 as compared with the case where the capacitor 50 is removed.
  • the time required for the voltage to return to the steady state has also been improved to about 100 ns. From this, according to the fourth embodiment, it is possible to reduce noise caused by generation of terahertz light.
  • the space between the conductive films 24 and 25 itself is also a capacity. Since the conductive films 24 and 25 are very thin, the capacity of this capacitor is very small and the amount of charge that can be stored is very small. If the capacitor 50 is not provided, the terahertz light is generated. The resulting noise was loud.
  • the condenser 50 is provided separately from the terahertz light generation element 21a.
  • the Terahertz light generation element 21a If the capacitance between the two conductive portions is increased, the capacitor 50 may not be provided separately from the terahertz light generating element 21a (of course, the capacitor 50 may be provided), and the terahertz light may be provided. Noise generated due to the generation can be reduced.
  • the capacitance between the two conductive portions of the terahertz light generation element 21a is 10 pF or more. In order to enhance the noise reduction effect, this capacitance is more preferably 100 pF or more, more preferably 0.01 or more, more preferably IF or more, and 100 F or more. Is more preferable.
  • FIG. 17 is a schematic sectional view showing a terahertz light generation element 21b used in the terahertz light generation device according to the fifth embodiment of the present invention, which corresponds to FIG. 12 (b). ing. Although only the vicinity of the conductive films 24 and 25 is shown in FIG. 17, the substrate 22 is formed so as to form a plano-convex lens as in the fourth embodiment.
  • the same or corresponding elements as those in FIGS. 11 and 12 (a) and 12 (b) are denoted by the same reference numerals, and redundant description thereof will be omitted.
  • the terahertz light generation device uses a terahertz light generation device 21b shown in FIG. 17 instead of the terahertz light generation device 21a shown in FIG. And the capacitor 50 is not connected.
  • the capacitor 50 may be connected as it is.
  • the difference between the terahertz light generating element 21b shown in FIG. 17 and the terahertz light generating element 21a shown in FIGS. 11 and 12 (a) and (b) is that the conductive films 24 and 25 Is that the thickness d is increased.
  • the thickness d is preferably, for example, 2 zm or more.
  • the thickness of the two conductive films 24 and 25 is more preferably 10 m or more, more preferably 100 im or more, and more preferably 1 mm or more. More preferably, it is 10 mm or more.
  • the conductive films 24 and 25 may be deposited films of metal such as gold.
  • Two As one conductive portion for example, two metal thin plates may be used instead of the conductive films 24 and 25. If a thin metal plate is used, the thickness can be easily increased. In the case of a thin metal plate, for example, it may be joined to the substrate 22 with a conductive adhesive or the like.
  • FIGS. 18 (a) to 18 (c) are diagrams showing a terahertz light generation element 21c used in a terahertz light generation device according to a sixth embodiment of the present invention.
  • FIG. 18 (a) is a schematic perspective view
  • FIG. 18 (b) is a schematic plan view
  • FIG. 18 (c) is a schematic cross-sectional view along the line XI-XI in FIG. 18 (b).
  • 18 (a) to 18 (c) show only the vicinity of the conductive films 24 and 25, but the base material 22 is formed so as to form a plano-convex lens as in the fourth embodiment. Have been.
  • FIGS. 18 (a) to 18 (c) the same or corresponding elements as those in FIGS. 11 and 12 (a) and 12 (b) are denoted by the same reference numerals, and overlapping description will be omitted.
  • the terahertz light generating element 21c shown in FIGS. 18 (a) to 18 (c) is a flat dielectric over the whole (or a part) of the conductive films 24 and 25 at a predetermined interval g.
  • the member 70 is arranged.
  • portions 24 d and 25 d of each of the two conductive films 24 and 25 facing the other conductive film rise from the surface of the substrate 22 as a photoconductive portion along each end surface of the dielectric member 70. Is attached.
  • a material of the dielectric member 70 it is preferable to use a dielectric material (for example, glass or the like) having little influence on the excitation pulse light.
  • capacitor 50 is not connected to the conductive films 24 and 25, but may be connected. '
  • the manufacturing of the terahertz light generating element 21c is performed, for example, by bonding a dielectric member 70 on the substrate 22 with an adhesive or the like, and masking the upper surface of the dielectric member 70 to deposit gold or the like.
  • This can be performed by forming conductive films 24 and 25 having raised opposing portions 24 d and 25 d.
  • the thickness of the dielectric member 70 is about several mm
  • the thickness of the conductive film is about 0.15 xm
  • the thickness of the substrate 22 is about 360
  • the opposing portions 24d, 25d of the conductive films 24, 25 rise and the dielectric member 70 is disposed between the opposing portions 24d, 25d.
  • the capacitance between the conductive films 24 and 25 of the terahertz light generation element 21c further increases, and the noise reduction effect increases.
  • FIG. 19 is a schematic perspective view showing a terahertz light generation element 21 d used in the terahertz light generation device according to the seventh embodiment of the present invention.
  • the base member 22 is formed so as to form a plano-convex lens, as in the fourth embodiment.
  • the same reference numerals are given to the same or corresponding elements as those in FIGS. 18 (a) to 18 (c), and the overlapping description will be omitted.
  • the difference between the terahertz light generating device according to the present embodiment and the sixth embodiment is that the terahertz light generating device 21 d shown in FIG. 19 is used instead of the terahertz light generating device 21 c.
  • the terahertz light generating device 21 d shown in FIG. 19 is used instead of the terahertz light generating device 21 c.
  • the whole (or part) of the part 7 1 a, 7 lb of each of the two metal sheets 71, 72 facing the other metal sheet is higher than the height of the other parts of the metal sheet, and serves as a photoconductive part. From the surface of the substrate 22.
  • the terahertz light generating element 21d For the manufacture of the terahertz light generating element 21d, for example, thin metal plates 71 and 72 having portions 71a and 71b raised by bending are prepared.
  • the terahertz light generation element 21 d can be manufactured by joining these metal thin plates 71 and 72 to the substrate 22 with a conductive adhesive or the like.
  • the capacitance between the thin metal plates 71 and 72 is slightly higher than in the sixth embodiment. Although smaller, advantages similar to those of the sixth embodiment can be obtained.
  • a dielectric member may be provided between the facing portions 71a and 71b.
  • FIG. 20 shows a configuration of the terahertz light generator according to the eighth embodiment of the present invention.
  • FIG. 3 is a schematic perspective view showing a terahertz light generating element 21 e.
  • the same or corresponding elements as those in FIGS. 11 and 12 (a) and (b) are denoted by the same reference numerals, and redundant description will be omitted.
  • the difference between the terahertz light generating device according to the present embodiment and the fourth embodiment is that the terahertz light generating device 21 e shown in FIG. 20 is used instead of the terahertz light generating device 21a. Are used and the capacitor 50 is removed. The capacitor 50 may be connected as it is.
  • the terahertz light generation element 21 e shown in FIG. 20 has a rod-shaped metal member 73, 74 having a rectangular cross section on the upper surface on the other conductive film side in each of the conductive films 24, 25. Each is joined by a conductive adhesive or the like.
  • conductive film 24 and metal member 73 constitute one conductive portion
  • conductive film 25 and metal member 74 constitute another conductive portion. That is, as in the seventh embodiment, the whole (or a part) of the portion of each of the two conductive portions facing the other conductive portion is higher than the height of the other portion of the conductive portion, and The rising from the surface of the substrate 22 as a conduction part. Thereby, the same advantages as in the seventh embodiment can be obtained.
  • a capacitor 50 can be connected between the conductive films 24 and 25. Also in this case, noise generated due to the generation of terahertz light can be reduced.
  • the substrate 22 of the terahertz optical element is configured as a plano-convex lens.
  • a Fresnel lens or a gradient index lens may be configured. May be formed.
  • the base material 22 does not necessarily need to be formed so as to perform the function of a convex lens, and may be formed so as to perform various lens functions such as a concave lens and a cylindrical lens as needed.
  • the femtosecond pulse laser light is used for generating or detecting the terahertz light.
  • other ultrashort pulse light may be used as the excitation pulse light. it can.
  • three or more conductive films separated from each other are formed on a photoconductive film
  • an array of a plurality of optical switch elements can be formed.
  • the substrate 22 is formed in a lens array so that the substrate 22 forms a plurality of lenses respectively corresponding to the plurality of optical switch elements.
  • the frequency spectrum of the obtained terahertz pulse light can be easily switched.
  • the predetermined distance between the two conductive films 24 and 25 of the terahertz optical element of the fourth embodiment is 2 mm, it may be 2 mm or more.
  • a large-diameter optical switch element as disclosed in the aforementioned article (IEEE Journal of Quantum Electronics, Vol. 32, No. 10, ppl 839-1846 (1996)) is obtained. If no configuration for obtaining the noise reduction effect is adopted, the noise generated by the generation of the terahertz light increases. Therefore, when the predetermined interval is increased, the noise reduction effect described in the fourth to eighth embodiments is particularly remarkable.
  • the predetermined interval between the conductive films 24 and 25 may be a minute interval of, for example, several meters to several tens of meters.
  • a dipole antenna, a bowtie antenna, and the like can be configured by two conductive portions.
  • the terahertz light generation device and the terahertz light detection device according to the present invention can be used for various devices using terahertz light.
  • the present invention can be applied to a spectroscope using terahertz light, an inspection device for semiconductors, medical devices, foods, etc., and an imaging device. In this case, improvement of accuracy, expansion of measurement range, reduction of measurement time, etc. can be realized. ⁇

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optics & Photonics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

La présente invention concerne un élément à lumière térahertzienne constitué d'un substrat, d'un film photoconducteur formé sur le plan du substrat, et de deux films conducteurs séparés l'un de l'autre, formés sur le film photoconducteur. Les parties correspondantes des films conducteurs sont agencées à une distance définie (d) les unes des autres selon un axe dans le plan du substrat. Le substrat est formé de façon à agir comme une lentille par rapport à la lumière térahertzienne partant du substrat vers le côté opposé du film photoconducteur ou en incidence sur le substrat en partant du côté opposé du film photoconducteur.
PCT/JP2002/000591 2001-01-26 2002-01-28 Élément générant de la lumière térahertzienne, générateur et détecteur de lumière térahertzienne WO2002060017A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2001018544A JP2002223017A (ja) 2001-01-26 2001-01-26 テラヘルツ光素子、並びに、これを用いたテラヘルツ光発生装置及びテラヘルツ光検出装置
JP2001-18544 2001-01-26
JP2001-170318 2001-06-05
JP2001170318A JP2002368250A (ja) 2001-06-05 2001-06-05 テラヘルツ光発生素子及びテラヘルツ光発生装置

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006010301B3 (de) * 2006-03-07 2007-06-06 Batop Gmbh Anordnung zur Emission und zum Empfang von Terahertz Strahlung
DE102008031751B3 (de) * 2008-07-04 2009-08-06 Batop Gmbh Photoleitende Antenne zur Abstrahlung oder zum Empfang von Terahertz-Strahlung
US7595498B2 (en) * 2004-08-05 2009-09-29 Panasonic Corporation Electromagnetic wave generation apparatus and manufacturing method of electromagnetic wave generation apparatus
GB2484407A (en) * 2010-10-08 2012-04-11 Korea Electronics Telecomm Terahertz photoconductive antenna layer deposited on a condenser lens
EP2466686A1 (fr) 2010-12-15 2012-06-20 Philipps-Universität Marburg Antenne d'émission et de réception de rayonnement GHz et/ou THz ayant une caractéristique de fréquence optimisée
US20140217288A1 (en) * 2011-09-30 2014-08-07 Sony Corporation Photoconductive element, lens, terahertz emission microscope and method of producing device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53126571U (fr) * 1977-03-14 1978-10-07
JPS5774720A (en) * 1980-10-29 1982-05-11 Nippon Sheet Glass Co Ltd Optoelectronic element
US5401953A (en) * 1993-09-23 1995-03-28 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Optically-switched submillimeter-wave oscillator and radiator having a switch-to-switch propagation delay
EP0828143A2 (fr) * 1996-09-09 1998-03-11 Lucent Technologies Inc. Système optique utilisant de la radiation terrahertz

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53126571U (fr) * 1977-03-14 1978-10-07
JPS5774720A (en) * 1980-10-29 1982-05-11 Nippon Sheet Glass Co Ltd Optoelectronic element
US5401953A (en) * 1993-09-23 1995-03-28 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Optically-switched submillimeter-wave oscillator and radiator having a switch-to-switch propagation delay
EP0828143A2 (fr) * 1996-09-09 1998-03-11 Lucent Technologies Inc. Système optique utilisant de la radiation terrahertz

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
KIYOMI SAKAI ET AL.: "Handotai oyobi koon cho dendotai niyoru tera hertz denjiha no hasshin", REVIEW OF THE COMMUNICATIONS RESEARCH LABORATORY, vol. 43, no. 4, 25 December 1997 (1997-12-25), pages 637 - 650, XP002950790 *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7595498B2 (en) * 2004-08-05 2009-09-29 Panasonic Corporation Electromagnetic wave generation apparatus and manufacturing method of electromagnetic wave generation apparatus
DE102006010301B3 (de) * 2006-03-07 2007-06-06 Batop Gmbh Anordnung zur Emission und zum Empfang von Terahertz Strahlung
DE102008031751B3 (de) * 2008-07-04 2009-08-06 Batop Gmbh Photoleitende Antenne zur Abstrahlung oder zum Empfang von Terahertz-Strahlung
GB2484407A (en) * 2010-10-08 2012-04-11 Korea Electronics Telecomm Terahertz photoconductive antenna layer deposited on a condenser lens
GB2484407B (en) * 2010-10-08 2013-04-03 Korea Electronics Telecomm Condenser lens-coupled photoconductive antenna device for terahertz wave generation and detection and fabricating method thereof
EP2466686A1 (fr) 2010-12-15 2012-06-20 Philipps-Universität Marburg Antenne d'émission et de réception de rayonnement GHz et/ou THz ayant une caractéristique de fréquence optimisée
WO2012080105A1 (fr) 2010-12-15 2012-06-21 Philipps Universität Marburg Antenne servant à émettre et à recevoir un rayonnement en ghz et/ou thz à caractéristique de fréquence optimisée
US20140217288A1 (en) * 2011-09-30 2014-08-07 Sony Corporation Photoconductive element, lens, terahertz emission microscope and method of producing device
US9146390B2 (en) * 2011-09-30 2015-09-29 Sony Corporation Photoconductive element, lens, terahertz emission microscope and method of producing device

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