JP5147033B2 - Sensor, sensor array, current measuring device - Google Patents

Description

  The present invention relates to a sensor, a sensor array, and a current measuring device, and more particularly to a sensor, a sensor array, and a current measuring device that use electromagnetic waves in the ultraviolet region as input energy.

  In recent years, with the spread of ultraviolet lithography and the like, the importance of ultraviolet sensors in industrial processes is increasing. In addition, the necessity of an ultraviolet sensor for environmental monitoring is increasing for areas with a large amount of irradiated ultraviolet rays, and for weak UV rays such as infants and whites. In addition, development of a small and high-performance ultraviolet sensor is expected as a technology for multifunctional portable electronic devices.

The following are known ultraviolet sensors as conventional techniques.
(1) Ultraviolet sensor using silicon semiconductor (for example, see Patent Document 1 and Patent Document 2)
A PN junction interface is formed by bonding, lamination, or the like using silicon P-type and N-type semiconductors. For example, as shown in FIG. 6, a P + type impurity layer 52 and an N + type diffusion layer 56 are formed on an N type silicon substrate 51. Further, a pair of electrodes that can apply a voltage to the semiconductor interface is formed. Here, an aluminum electrode 54 connected to the P + type impurity layer 52 and an aluminum electrode 55 connected to the N + type diffusion layer 56 are provided. A voltage is applied to these electrodes from the outside. In the figure, reference numeral 53 denotes a Si oxide film.

  When the ultraviolet ray hν is incident on the PN junction interface of the ultraviolet sensor thus produced, an electron and hole pair is generated in the film, and this is detected through the electrodes 54 and 55. This ultraviolet sensor mainly targets long wavelength ultraviolet rays of 250 [nm] or more. In this case, the band gap energy of the semiconductor is often in the visible light region, and a UV transmission filter 57 for blocking visible light is required.

(2) Ultraviolet sensor using diamond thin film (for example, see Patent Document 3)
Diamond is an insulator in an undoped state, but can be made into a semiconductor by doping an impurity element. As shown in FIG. 7, a doped diamond film 62 is formed on the substrate 61. The first electrode 63 and the second electrode 64 are connected to the diamond film 62, and ultraviolet sensing is performed by the same method as in (1) above. This ultraviolet sensor mainly targets short wavelength ultraviolet rays of 250 [nm] or less.

(3) Ultraviolet sensor using zinc sulfide (see, for example, Patent Document 4)
Using zinc sulfide as a dielectric material sensitive to ultraviolet rays, a capacitor is formed by a laminated structure sandwiched between upper and lower electrodes. As shown in FIG. 8, a photosensitive dielectric 73 and a lower dielectric 74 are used, and a transparent upper electrode 72 and a transparent material 71 are provided above them. In addition, a lower layer electrode 75 and a protective material 76 are provided below these. With this configuration, the capacitor C is formed between the upper electrode 72 and the lower electrode 75. When light enters the photosensitive dielectric 73, the dielectric constant of the photosensitive dielectric 73 changes, so that the light intensity can be detected by the change. For example, as shown in FIG. 9, an optical sensor 81 having this capacitor is used as a capacitor of a CR oscillator 82 (or LC oscillator), and the oscillation frequency of the oscillator is counted by a frequency counter 83 to change the capacitance. If the change is processed by the microcomputer 84, the light intensity can be detected.

(4) Ultraviolet sensor using capacitance change of dielectric crystal (for example, see Patent Document 5)
As shown in FIG. 10A, a gold electrode 93 is formed on a dielectric crystal 92 to constitute a capacitor 91. Further, light is irradiated by the light irradiation means 97 through the stripe-shaped intervals 94.
Then, as shown in FIG. 5B, the capacitance change of the capacitor 91 is detected by connecting the capacitance 96 to the gold electrode 93 by the wiring 103 and the wiring 98. In addition, by placing the capacitor 91 in the thermostatic chamber 95, the dielectric crystal 92 is maintained near the phase transition temperature. An input signal to the input means 102 is input to the light irradiation means 97 via the wiring 101 to the control means 100, and the light is irradiated to the dielectric crystal 92 by controlling the light irradiation means 97 via the wiring 99. . By controlling the dielectric constant of the crystal by applying an electric field or a magnetic field, the capacitance change can be detected with high sensitivity. Further, the crystal has a band gap energy larger than that of visible light.

(5) By the way, as a photosensitive characteristic against ultraviolet rays, it is conceivable to use the photovoltaic effect of a dielectric other than the above. The following applications have been proposed for this characteristic.
(A) Optical switch (for example, see Non-Patent Document 1)
(A) Optical walking robot (for example, see Non-Patent Document 2)
(C) Optical micro gripper (for example, see Non-Patent Document 3)
(D) Light driving mechanism (for example, see Non-Patent Document 4)
(E) Electrostatic motor (for example, see Patent Document 6)
(F) Non-electric power supply method (for example, refer to Patent Document 7)
As a main substance exhibiting the photovoltaic effect, lead lanthanum zirconate titanate (PLZT) is used. Technology development for improving the characteristics of the PLZT element itself has also been performed (see, for example, Patent Documents 8 to 10).

Further, a photosensitive structure for improving the photocurrent which is generally at the nA level is described in the specification of Japanese Patent Application No. 2003-11086. In this specification, an output current is improved by forming a vertical stacked structure by arranging electrodes in the vertical direction of the film-like structure.
JP-A-7-162024 JP-A-7-162025 Japanese Patent Laid-Open No. 11-284531 JP 2003-294527 A JP 2003-209266 A Japanese Patent Application Laid-Open No. 2002-078360 Japanese Patent No. 3265479 Japanese Patent No. 2716083 Japanese Patent No. 3041409 Japanese Patent No. 3106187 M. Tanimura and K. Uchino; Sensors and Materials 1 (1988) 47-56 K. Uchino; J. Rob. Mech. 1 (1989) 124-127) Hattori, Fukuda, Maruhashi, Matsuura, Nagamori The Japan Society of Mechanical Engineers Proceedings C59 (1993) 799-806 H. Ishihara and T. Fukuda; J. Rob. Mech. 11 (1999) 436-442

However, the above technique has the following problems.
In a method using a semiconductor (Patent Document 1 to Patent Document 3), it is necessary to create an interface of different materials using bonding or lamination patterning. Furthermore, it is necessary to be able to apply a voltage to the interface through an electrode formed in contact with these materials, and accordingly, a voltage application circuit and a power supply are required.

  The methods using the capacitance change (Patent Documents 4 and 5) have the following problems. In Patent Document 4, it is necessary to arrange a CR oscillator or an LR oscillator outside. In patent document 5, arrangement | positioning of a temperature control apparatus is required. It is necessary to maintain the sensor material in a critical state. In addition, it is necessary to apply an electric field or a magnetic field to the element.

Here, for the photovoltaic effect of the ferroelectric, it is necessary to apply an external voltage, which was indispensable in Patent Documents 1 to 5. However, there are problems as shown below in examining the application. To do.
First, in the case of the ceramic polycrystalline PLZT element used in the above-described conventional technology (see Non-Patent Document 1 to Non-Patent Document 4 and Patent Document 6 to Patent Document 10), the voltage generated by the photovoltaic effect is Although it is high at kV or higher, the generated current is small at the level of nA. It is necessary to improve the compatibility with existing electronic devices by increasing the current by at least about 3 digits.

  On the other hand, the voltage can be applied sufficiently at the V level. In Patent Document 10, a single crystal material is used, but the photovoltaic characteristic is equivalent to that of a polycrystalline fired body. Conventionally, when a polycrystalline sintered body (bulk body) or a single crystal is used as a photovoltaic element and mounted on an electronic device such as MEMS (Micro Electro Mechanical System), it is necessary to use an adhesive or the like. There were problems from the viewpoint of quality assurance and dumping.

Furthermore, the functional structure described in the specification of the above-mentioned Japanese Patent Application No. 2003-111086 is connected to a special measuring instrument capable of measuring an extremely small current, although it can output an electric output with respect to ultraviolet rays. There is a problem that the performance evaluation can be performed only for the first time.
Moreover, in order to use as a sensor, it is necessary to add a calculation and an external display function. Furthermore, when it is used for industrial purposes, it is necessary to display the accumulated dose, but it is necessary to add a control circuit having such a calculation function.

Therefore, development of an ultraviolet sensor incorporating an external circuit using a laminated structure of photovoltaic elements by a thin film and thick film forming method having good consistency with a MEMS process and a semiconductor manufacturing process is expected.
The present invention has been made to solve the above problems, and its purpose is to provide a compact, large current output sensor, sensor array, and current that do not require external voltage application, which is indispensable for semiconductor sensors. It is to realize a measuring device.

The sensor array according to claim 1 of the present invention includes a first electrode group arranged in a predetermined direction, and a second electrode group arranged in a direction crossing the arrangement direction of the first electrode group, by photovoltaic unit using the dielectrics at the intersection of the second electrode group and the first electrode group are provided, and the photovoltaic unit using the membrane structure of the dielectric, the Including a pair of electrodes provided with a photovoltaic part sandwiched therebetween, wherein the photovoltaic part and the pair of electrodes are vertically stacked, and at least one of the pair of electrodes is transparent. A sensor that is made of a material having a property and derives electric power according to the energy of light irradiated on the photovoltaic part without applying a bias voltage is formed at the intersection, and the output of each formed sensor It is characterized by deriving. In this way, it is possible to configure a compact sensor capable of obtaining a large current output that does not require application of an external voltage, which is indispensable in a semiconductor sensor. Further, even when the light incident direction and the polarization direction are parallel, the photovoltaic portion can be irradiated with light. As the light-transmitting material, for example, tin-added indium oxide, zirconium oxide, or the like can be used. If the sensor array is configured in this way, the light irradiation position can be specified by the output of each sensor.

A sensor array according to a second aspect of the present invention is the sensor array according to the first aspect, wherein the dielectric film structure includes at least one of a thin film, a thick film, and a bulk flake made of either a polycrystal or a single crystal. Is used. In this way, it is possible to easily construct a compact sensor array that can provide a large current output, which does not require external voltage application, which is indispensable for semiconductor sensors.

A sensor array according to a third aspect of the present invention is characterized in that, in the first or second aspect, the photovoltaic portion is formed of one of a lead-containing dielectric and a non-lead-containing dielectric. In this way, a sensor array having suitable characteristics can be obtained.
A sensor array according to a fourth aspect of the present invention is the sensor array according to the third aspect, wherein the lead-containing dielectric and the non-lead-containing dielectric are made of at least one kind of compound of either a polycrystalline or a single crystal. The material material is used alone. In this way, a sensor array having suitable characteristics can be obtained.

A sensor array according to a fifth aspect of the present invention is the sensor array according to the third aspect, wherein the lead-containing dielectric and the non-lead-containing dielectric are made of at least one compound composed of at least one of a polycrystal and a single crystal. The material is characterized by being used with at least one trace additive added. In this way, a sensor array having suitable characteristics can be obtained.

The sensor array according to claim 6 of the present invention is the sensor array according to claim 5, wherein the trace additive includes tungsten, tantalum, niobium, iron, copper, magnesium, bismuth, yttrium, molybdenum, vanadium, sodium, potassium, aluminum, manganese , Nickel, zinc, calcium, strontium, silicon, tin, selenium, neodymium, erbenium, thulium, hafnium, praseodymium, promethium, samarium, eurobium, gadolinium, terbium, dysprosium, ytterbium, lithium, scandium, barium, lanthanum, actinium, cerium , Ruthenium, osmium, cobalt, palladium, silver, cadmium, boron, gallium, germanium, phosphorus, arsenic, antimony, fluorine, tellurium, lutetium Characterized in that at least one is selectively used. In this way, a sensor array having suitable characteristics can be obtained.

The sensor array according to claim 7 of the present invention is the sensor array according to any one of claims 3 to 6, wherein the lead-containing dielectric is PLZT, PZT, PMN, PbTiO ₃ , PbTiO ₃ -La (Zn _{2 / 3} Nb _1/3 ) O ₃ , PbTiO ₃ -Pb (Mg _1/2 W _1/2 ) O ₃ or 0.91Pb (Zn _1/3 Nb _2/3 ) O3-0.09PbTiO ₃ is selectively used It is characterized by being made. In this way, a sensor array having suitable characteristics can be obtained.

A sensor array according to an eighth aspect of the present invention is the sensor array according to any one of the third to sixth aspects, wherein the lead-free dielectric includes BaTiO ₃ , LiNbO ₃ , KNbO ₃ , NaNbO ₃ , (K, Na) NbO ₃ , ZnO, SbSI, RbZnBr ₄ , TGS, PVDF, P (VDF / TrFE), GaP, La ₂ S ₃ , Gd ₂ S ₃ , D ₂ S ₃ , CuPs ₅ Br, Bi ₁₂ SiO ₂₀ , Bi ₁₂ GeO ₂₀ , Bi ₁₂ TiO ₂₀ , Te, SiO ₂ , HgS, (Ba, Ca) TiO ₃ , CaBi ₄ Ti ₄ O ₁₅ , Ba ₃ TaGa ₃ Si ₂ O ₁₄ , La ₃ Ga ₅ SiO ₁₄ , Ca ₃ Ga ₂ Ge ₄ O ₁₄ , Sr ₃ TaGa ₃ Si ₂ O ₁₄ , BIT (Bi _4-x Pr _x Ti ₃ O ₁₂ ), BTZ (Ba (Ti _1-x Zr _x ) O ₃ ), LNN ((Li, Na ) NbO ₃ ) is selectively used. In this way, a sensor array having suitable characteristics can be obtained.

The sensor array according to claim 9 of the present invention is the sensor array according to any one of claims 1 to 8, wherein the photovoltaic portion is formed by an oxide baking method, a sol-gel method, a MOD method, sputtering, an electron Beam deposition, laser deposition, vacuum deposition, MOCVD, CVD, electrophoresis, interfacial polymerization, hydrothermal synthesis, gas deposition, aerosol deposition, spray coating, and screen printing At least one of the methods is used. In this way, a sensor array having suitable characteristics can be obtained.

The sensor array according to claim 10 of the present invention is the sensor array according to claim 9, wherein the photovoltaic portion is formed by heat assist such as substrate heating, microwave irradiation, laser annealing, surface activation by plasma or laser irradiation, and Further, at least one method of atmospheric control such as pressure reduction and gas replacement is further used as an auxiliary process. If it does in this way, a sensor array can be created suitably.

A sensor array according to an eleventh aspect of the present invention is the sensor array according to any one of the first to tenth aspects, wherein the photovoltaic portion and the pair of electrodes constituting the sensor are continuously arranged in at least one direction. It is characterized by that. In this way, by adopting a structure in which photovoltaic materials are stacked in a plurality of layers in the vertical direction or arranged in a plurality of planes in at least one direction, the output power can be amplified and detected in a large area. Is possible.

A sensor array according to a twelfth aspect of the present invention is the sensor array according to the eleventh aspect , wherein a plurality of the intersections exist, and the dielectric is provided in common to the plurality of the intersections.

According to a thirteenth aspect of the present invention, there is provided a current measuring apparatus including the sensor array according to any one of the first to twelfth aspects, and a calculation unit that calculates the output current. If comprised in this way, the output electric current derived | led-out by light irradiation can be measured.
According to a fourteenth aspect of the present invention, in the thirteenth aspect , the current measuring device further includes a display unit that displays a calculation result of the calculation unit. If comprised in this way, the measured value of output current can be confirmed visually.

  According to the present invention, the power corresponding to the energy of the light irradiated to the photovoltaic part, including the photovoltaic part using a dielectric and the pair of electrodes provided with the photovoltaic part interposed therebetween. By adopting the configuration for deriving the above, it is possible to realize a compact sensor capable of obtaining a large current output without applying an external voltage, which is indispensable for a semiconductor sensor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings referred to in the following description, the same parts as those in the other drawings are denoted by the same reference numerals.
(Sensor configuration)
FIG. 1 is a block diagram showing the configuration of an embodiment of a sensor according to the present invention. The sensor shown in the figure is configured to include the ultraviolet photosensitive portion 1 and has a function of measuring the amount of ultraviolet irradiation and the amount of accumulated charge.
The sensor shown in the figure includes an arithmetic circuit 2, an output circuit 3, and a display unit 7.

  The arithmetic circuit 2 includes a current / voltage converter 5 and an A / D converter 8 realized by a microcomputer 6. In the arithmetic circuit 2, the current 140 generated in the ultraviolet photosensitive unit 1 is converted into a voltage by the current-voltage converter 5 using an operational amplifier. Further, the analog signal 150 that is the converted voltage is converted into a digital signal by the A / D converter 8. The current conversion operation unit 9 performs an operation for converting the converted digital signal into a current value, and calculates current value data proportional to the amount of ultraviolet light. Further, the current value integration calculation unit 10 integrates the current value data for each time to calculate the accumulated charge amount, that is, the total power amount. The output of the current conversion calculation unit 9 and the output of the current value integration calculation unit 10 are input to the display drive signal conversion unit 11 that functions as the output circuit 3. The display drive signal converter 11 converts the current value data into a drive signal for driving the display 4. The converted drive signal is sent to the display unit 7 having the display 4. The display drive signal converter 11 is realized by the microcomputer 6.

The display 4 includes a current display unit 12, a charge display unit 13, an irradiation light amount display unit 14, and an accumulated dose display unit 15, and receives a signal sent from the output circuit 3 and receives characters. Convert to and display. Thereby, the output current of the sensor and the accumulated charge amount calculated by calculating this output current can be displayed.
The power necessary for operating the microcomputer 6 may be supplied by a battery or a solar battery.

(Structure of UV sensitive part)
FIG. 2 is a diagram showing an example of a laminated structure of the ultraviolet photosensitive part 1 using a film structure. The ultraviolet photosensitive portion includes, in order from the bottom, a silicon oxide (SiO ₂ ) film 21, a silicon (Si) substrate 22, a silicon oxide film 23, a lower electrode composed of a titanium (Ti) film 24 and a platinum (Pt) film 25, a photovoltaic device. A film structure 26 serving as a power section and an upper electrode 27 formed of a tin-added indium oxide (ITO) film are included. That is, the ultraviolet photosensitive part includes a photovoltaic part and a pair of electrodes provided with the photovoltaic part sandwiched therebetween, and derives electric power according to the energy of light applied to the photovoltaic part. It has a function.

The film structure 26 can be constituted by a polycrystalline fired body of a photovoltaic material, a single crystal bulk flake, a thin film or a thick film. Bulk flakes can be obtained by polishing or cutting the bulk body to 100 μm or less.
As the photovoltaic material, it is preferable to use a lead-containing dielectric or a non-lead-containing dielectric. For lead-containing dielectrics or non-lead-containing dielectrics, a base material consisting of a single or a plurality of compounds of a polycrystal or a single crystal is used alone, or a trace additive is added alone or a plurality thereof. It is preferable to use it.

Examples of the lead-containing dielectric include PLZT, PZT, PMN, PbTiO ₃ , PbTiO ₃ -La (Zn _2/3 Nb _1/3 ) O ₃ , PbTiO ₃ -Pb (Mg _1/2 W _1/2 ) O ₃ Alternatively, it is preferable to use 0.91Pb (Zn _1/3 Nb _2/3 ) O3-0.09PbTiO ₃ .
The lead-free dielectric materials include BaTiO ₃ , LiNbO ₃ , KNbO ₃ , NaNbO ₃ , (K, Na) NbO ₃ , ZnO, SbSI, RbZnBr ₄ , TGS, PVDF, P (VDF / TrFE), GaP, La ₂ S ₃ , Gd ₂ S ₃ , D ₂ S ₃ , CuPs ₅ Br, Bi ₁₂ SiO ₂₀ , Bi ₁₂ GeO ₂₀ , Bi ₁₂ TiO ₂₀ , Te, SiO ₂ , HgS or (Ba, Ca) TiO ₃ , CaBi ₄ Ti ₄ O ₁₅ , Ba ₃ TaGa ₃ Si ₂ O ₁₄ , La ₃ Ga ₅ SiO ₁₄ , Ca ₃ Ga ₂ Ge ₄ O ₁₄ , Sr ₃ TaGa ₃ Si ₂ O ₁₄ , BIT (Bi _4-x Pr _x Ti ₃ O _{12), BTZ (Ba (Ti} 1-x Zr x) O 3), it is preferred to use LNN ((Li, Na) NbO 3).

  The above trace additives include tungsten, tantalum, niobium, iron, copper, magnesium, bismuth, yttrium, molybdenum, vanadium, sodium, potassium, aluminum, manganese, nickel, zinc, calcium, strontium, silicon, tin, selenium, neodymium. , Erbium, thulium, hafnium, praseodymium, promethium, samarium, eurobium, gadolinium, terbium, dysprosium, ytterbium, lithium, scandium, barium, lanthanum, actinium, cerium, ruthenium, osmium, cobalt, palladium, silver, cadmium, boron, gallium It is preferable to use one or two or more selected from the group consisting of germanium, phosphorus, arsenic, antimony, fluorine, tellurium and lutetium. Arbitrariness.

(Membrane structure creation)
In this example, the PLZT film is the film structure 26. The film structure 26 made of the PLZT film was a film structure composed of a plurality of thin films.
In the ultraviolet photosensitive part 1, the light incident direction and the polarization direction are used in parallel. For this reason, it is necessary to use a translucent material for the upper electrode 27 instead of a general metal electrode. Here, an ITO film is used.
As shown in FIG. 2, when a structure in which a photovoltaic portion and a pair of electrodes are vertically stacked is employed, at least one of the electrodes is formed using a translucent electrode material. There is a need. On the other hand, when the photovoltaic part and the pair of electrodes are arranged side by side in the same layer, such as when the electrodes are arranged on the side, they are made using a general opaque metal electrode. It ’s fine.

Next, a process for creating the ultraviolet photosensitive part 1 will be described. The silicon oxide film 23 formed on the surface of the silicon substrate 22 is formed by heat treatment at 1100 degrees C. for 20 hours in a thermal diffusion furnace, and the film thickness is about 1.5 [μm].
A titanium film 24 and a platinum film 25 were sequentially formed on the silicon oxide film 23 as a lower electrode by a sputtering method. Here, the titanium film 24 was formed to 50 [nm], and the platinum film 25 was formed to 100 [nm].

  The PLZT film, which is the film structure 26, was dropped on the surface of the platinum film 25 of the UV photosensitive part 1 in progress on the spin coater using a MOD solution material made mainly of a compound such as alcoholate as a raw material. . Then, by rotating the spin coater from 500 [rpm] to 4000 [rpm], a uniform PLZT layer of about 100 [nm] per layer is applied using centrifugal force.

  The PLZT layer thus coated was heat-treated in an oxidation firing furnace to synthesize PLZT. The heat treatment temperature is 120 [° C.] for 2 minutes, 470 [° C.] for 5 minutes, and 650 [° C.] for 5 minutes. Thereby, a PLZT layer having a perovskite structure can be formed. Such a PLZT layer forming process is repeated 20 times to form a PLZT film, which is a film structure 26 having a thickness of 2 [μm], which is composed of a plurality of layers.

Next, as the upper electrode 27, an ITO film is formed with a film thickness of about 50 [nm] on the PLZT film as the film structure 26 by sputtering. At this time, masking is performed so that the area of the upper electrode 27 is 10 [mm] square.
The above-mentioned film structure is not limited to the above method, and the oxide film baking method, sol-gel method, MOD method, sputtering, electron beam evaporation, laser evaporation method, vacuum evaporation method, MOCVD method, CVD method, electrophoresis method, interface weight It may be formed by using one or a plurality of legal methods, hydrothermal synthesis methods, gas deposition methods, aerosol deposition methods, spray coating methods or screen printing methods.

(Polarization treatment)
In order to make the ultraviolet photosensitive part 1 produced as described above have a photovoltaic property, it is necessary to perform a polarization process by applying a voltage in advance in a direction in which the electric power is desired to be generated. In this example, a voltage of 1 [V] was applied between the lower electrode and the upper electrode 27 to perform polarization treatment.

(Photovoltaic characteristics of UV sensitive part)
FIG. 3 shows the light intensity dependency of the photovoltaic characteristics of the ultraviolet photosensitive portion 1. In the figure, the horizontal axis represents light intensity (mW / cm <2>), and the vertical axis represents photocurrent ([mu] A).
Referring to the figure, the maximum light intensity was 60 [mW / cm 2], and at that time, 1.0 [μA] photovoltaic was generated in the device.

(Configuration of sensor array)
FIG. 4 shows a configuration example of a sensor array according to the present invention.
Referring to the figure, the sensor array of the present example includes a first electrode group composed of a plurality of electrodes M1 to M6 arranged in the vertical direction in the figure, and a direction intersecting the arrangement direction of the first electrode group. A second electrode group composed of a plurality of electrodes N1 to N6 arranged in the lateral direction, and a film structure serving as a photovoltaic portion provided between the first electrode group and the second electrode group And a body 26. If the sensor array is configured in this way, a photovoltaic unit using a dielectric is provided at each of the intersections of the electrodes M1 to M6 belonging to the first electrode group and the electrodes N1 to N6 belonging to the second electrode group. Will be. That is, a sensor having a laminated structure is formed at each of the intersections. The outputs of the sensors formed in this way are derived from the lead terminals 32 and 33.

(Other configuration of sensor array)
You may comprise a sensor array by arrange | positioning the photovoltaic part and a pair of electrode which comprise a sensor continuously in at least one direction. In other words, the output power can be amplified by adopting a configuration in which a plurality of photovoltaic portions are stacked in the vertical direction or a configuration in which a plurality of photovoltaic portions are arranged in a plane in at least one direction. Yes, detection in a large area is possible.

(Configuration of current measuring device)
FIG. 5 shows a configuration of a current measuring device using the sensor array shown in FIG.
The current measuring device shown in FIG. 1 is composed of an ultraviolet photosensitive unit 31, lead terminals 32 and 33 for deriving an electrical signal from the ultraviolet photosensitive unit 1, an arithmetic circuit 34, and a display unit 35. ing.
The ultraviolet photosensitive part 31 shown in the figure can be produced by the same process as in the first embodiment.
In such a configuration, when ultraviolet light is incident on the ultraviolet photosensitive part 31, a photovoltaic current is generated due to the photovoltaic effect. The generated current is output from the lead terminals 32 and 33 through the upper and lower electrodes of the ultraviolet irradiation unit. The lead terminals 32 and 33 are connected to the arithmetic circuit 34.

  By scanning information from all the lead terminals 32 and 33, it is possible to display whether one or a plurality of sensors constituting the ultraviolet photosensitive unit 1 is irradiated with ultraviolet rays. When a plurality of sensors are irradiated, two-dimensional information of the light irradiation position can be derived from the output current. Thereby, the irradiation position of an ultraviolet-ray can be clarified. For this reason, this sensor array functions as a position sensor.

(application)
Above, the sensor according to the present invention, the sensor array has been described about the shape condition of implementation of the current measuring device, the present invention is not limited to such embodiments, the technical matters described claims It goes without saying that there are various embodiments within the scope. For example, when measuring and displaying the accumulated charge amount, separate the sensor and sensor array from the display calculation unit, and installing only the sensor and sensor array at the measurement location allows the display calculation unit to Can be prevented from being affected. Further, by adopting such a configuration, the amount of ultraviolet rays can be measured using the sensor, sensor array, and current measuring device of the present invention even when the measurement place is narrow.

(Summary)
(1) In the present invention, the photovoltaic effect of a dielectric is used for the ultraviolet sensing technology. This is a technical method that has not been proposed in the past. In particular, since the generation of the output current is caused by the physical properties of the material, the output can be taken out without the need to apply a voltage from the outside. In addition, since it is not necessary to create an interface, the structure can be simplified and the cost can be reduced.

(2) According to the present invention, the components can be simplified as compared with the conventional one. In particular, it is sufficient for the external circuit to have a control circuit with an arithmetic function and a display unit, and the conventional CR circuit or LC circuit, temperature controller, etc. are unnecessary, and simplification and cost reduction can be achieved. it can. Moreover, although all the conventional sensing materials required the element film thickness of several tens of micrometers or more, the sensing material of the present invention can sufficiently extract the output with a film thickness of several micrometers.

(3) Since the film structure formed of the thin film of the present invention can be formed using a thin film forming technique, it can be easily applied to MEMS. In particular, it can be used as a means for wirelessly supplying power to places where it is difficult to draw in electrical wiring, such as a high aspect ratio structure, a small high-speed rotating body, and a vacuum / water drive mechanism. If a plurality of film structures are stacked, the voltage can be increased.

(4) Since the photoelectric conversion structure according to the present invention uses a film structure made of a thin film as a light energy conversion element, the irradiated light almost hits the entire film. For this reason, there is no dead volume as in the case of a conventional sintered body, and the utilization efficiency of the element is improved. That is, since the sintered body used in the conventional technique has a thickness of about 500 [μm] or more, it did not reach the opposite surface irradiated with the irradiated light. For this reason, the electrical conductivity of the portion where light does not reach remains the dark conductivity value, and the contribution of photoconductivity cannot be received. On the other hand, in the case of the film structure, since the light reaches the entire element, the total electric conductivity increases, so that the flowing current increases rapidly.

(5) The cost can be reduced due to the simplification of the configuration and the components and the drastic reduction of the amount of diamond film and silicon used. Moreover, since it is manufactured without using a special process, it is expected that the technology will be smoothly spread.

  Since the present invention uses the photoelectric power effect of a dielectric, it is not necessary to create a junction interface when taking out the output current, it is not necessary to apply a voltage, and a film thickness of several microns is sufficient for output. It is characterized in that it can be taken out. This makes it possible to simplify the structure and reduce the cost. The above-described sensors and sensor arrays are suitable for relatively small sensor devices using MEMS or nanotechnology.

It is a block diagram which shows the structure of embodiment of the sensor by this invention. It is a figure which shows the laminated structure of the ultraviolet-sensitive part which uses a film | membrane structure. It is a figure which shows the light intensity dependence of the photovoltaic characteristic of an ultraviolet-sensitive part. It is a figure which shows the structural example of the sensor array by this invention. It is a figure which shows the structural example of the electric current measurement apparatus using the sensor array by this invention. It is a figure which shows the structural example of the conventional ultraviolet sensor using a silicon semiconductor. It is a figure which shows the structural example of the conventional ultraviolet sensor using a diamond thin film. It is a figure which shows the structural example of the conventional ultraviolet sensor using zinc sulfide. It is a figure which shows the structure for detecting light intensity using the ultraviolet sensor of FIG. (A) is a figure which shows the structure of the capacitor | condenser used for the conventional ultraviolet sensor using the capacitance change of a dielectric crystal, (b) is a figure which shows the structural example of the ultraviolet sensor using the capacitor | condenser of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultraviolet photosensitive part 2 Calculation circuit 3 Output circuit 4 Display 5 Current voltage conversion part 6 Microcomputer 7 Display part 8 A / D conversion part 9 Current conversion calculation part 10 Current value integration calculation part 11 Display drive signal conversion part 12 Current display part 13 Charge display unit 14 Irradiation light amount display unit 15 Accumulated dose display units 21 and 23 Silicon oxide film 22 Silicon substrate 24 Titanium film 25 Platinum film 26 Film structure 27 Upper electrode 31 Ultraviolet light sensitive units 32 and 33 Lead-out terminal 34 Arithmetic circuit 35 Display Part 51 N-type silicon substrate 52 P + type impurity layer 53 Si oxide films 54 and 55 Aluminum electrode 56 Type diffusion layer 57 Transmission filter 61 Substrate 62 Diamond film 63 First electrode 64 Second electrode 71 Transparent material 72 Upper electrode 73 Photosensitive dielectric Body 74 Lower layer dielectric 75 Lower layer electrode 76 Protective material 81 Optical sensor 82 Oscillator 83 Frequency counter 84 Ma Con 91 capacitor 92 dielectric crystal 93 gold electrode 95 a thermostat 96 volume 97 light irradiating means 98,99,101,103 wiring 100 control unit 102 input unit 140 current 150 analog signals M1-M6, N1 to N6 electrode

Claims (14)

A first electrode group arranged in a predetermined direction; and a second electrode group arranged in a direction intersecting with the arrangement direction of the first electrode group, wherein the first electrode group and the second electrode group by photovoltaic unit using the dielectrics at the intersection of the electrode group are provided,
Wherein the photovoltaic unit using the dielectric film structure, the and a pair of electrodes provided to sandwich the photovoltaic unit, the and the said pair of electrodes and the photovoltaic unit is stacked vertically And at least one of the pair of electrodes is made of a light-transmitting material, and the power corresponding to the energy of the light applied to the photovoltaic portion is applied without applying a bias voltage. A sensor array, wherein a sensor to be derived is formed at the intersection, and an output of each of the formed sensors is derived. 2. The sensor according to claim 1, wherein the dielectric film structure includes at least one of a thin film, a thick film, and a bulk flake made of one of a polycrystal and a single crystal. Array . 3. The sensor array according to claim 1, wherein the photovoltaic portion is configured by one of a lead-containing dielectric and a non-lead-containing dielectric. The lead-containing dielectric and the non-lead-containing dielectric are characterized in that a base material made of at least one kind of compound of either a polycrystal or a single crystal is used alone. 3. The sensor array according to 3. The lead-containing dielectric and the non-lead-containing dielectric are used by adding at least one trace additive to a base material made of at least one compound of either a polycrystal or a single crystal. The sensor array according to claim 4, wherein the sensor array is formed . The trace additive includes tungsten, tantalum, niobium, iron, copper, magnesium, bismuth, yttrium, molybdenum, vanadium, sodium, potassium, aluminum, manganese, nickel, zinc, calcium, strontium, silicon, tin, selenium, neodymium. , Erbium, thulium, hafnium, praseodymium, promethium, samarium, eurobium, gadolinium, terbium, dysprosium, ytterbium, lithium, scandium, barium, lanthanum, actinium, cerium, ruthenium, osmium, cobalt, palladium, silver, cadmium, boron, gallium , Germanium, phosphorus, arsenic, antimony, fluorine, tellurium, lutetium is selectively used. 5, wherein the sensor array. The lead-containing dielectric is PLZT, PZT, PMN, PbTiO ₃ , PbTiO ₃ -La (Zn _2/3 Nb _1/3 ) O ₃ , PbTiO ₃ -Pb
(Mg _1/2 W _1/2 ) O ₃ or 0.91Pb (Zn _1/3 Nb _2/3 ) O3-0.09PbTiO ₃ is selectively used. Item 7. The sensor array according to any one of Item 6 to Item 6. The lead-free dielectric includes BaTiO ₃ , LiNbO ₃ , KNbO ₃ , NaNbO ₃ , (K, Na) NbO ₃ , ZnO, SbSI, RbZnBr ₄ , TGS, PVDF, P (VDF / TrFE), GaP, La ₂ S ₃ , Gd ₂ S ₃ , D ₂ S ₃ , CuPs ₅ Br, Bi ₁₂ SiO ₂₀ , Bi ₁₂ GeO ₂₀ , Bi ₁₂ TiO ₂₀ , Te, SiO ₂ , HgS, (Ba, Ca) TiO ₃ , CaBi ₄ Ti ₄ O ₁₅ , Ba ₃ TaGa ₃ Si ₂ O ₁₄ , La ₃ Ga ₅ SiO ₁₄ , Ca ₃ Ga ₂ Ge ₄ O ₁₄ , Sr ₃ TaGa ₃ Si ₂ O ₁₄ , BIT (Bi _4-x Pr _x Ti ₃ O _{12), BTZ (Ba (Ti} 1-x Zr x) O 3), LNN ((Li, Na) NbO 3) of claim 3, characterized in that formed by selectively used to claim 6 The sensor array according to any one of the above. For the formation of the photovoltaic part, oxide baking method, sol-gel method, MOD method, sputtering, electron beam evaporation, laser evaporation method, vacuum evaporation method, MOCVD method, CVD method, electrophoresis method, interfacial polymerization method, water The method according to any one of claims 1 to 8, wherein at least one of a thermal synthesis method, a gas deposition method, an aerosol deposition method, a spray coating method, and a screen printing method is used. The sensor array according to claim 1. The formation of the photovoltaic portion is at least one of thermal assistance such as substrate heating, microwave irradiation, laser annealing, surface activation by plasma or laser irradiation, and atmospheric control such as pressure increase or gas replacement. 10. The sensor array according to claim 9, wherein one of the two methods is further used as an auxiliary process. The sensor array according to any one of claims 1 to 10, wherein the photovoltaic part and the pair of electrodes constituting the sensor are continuously arranged in at least one direction. 12. The sensor array according to claim 1, wherein there are a plurality of the intersections, and the dielectric is provided in common for the plurality of the intersections. A current measuring device comprising the sensor array according to any one of claims 1 to 12, and further comprising a calculation unit that calculates an output current thereof. The current measuring device according to claim 13, further comprising a display unit that displays a calculation result of the calculation unit.

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