JP2002344001A - Wavelength separation type ultraviolet receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small, simple, and inexpensive ultraviolet receiver, capable of simultaneously separating and precisely and stably measuring ultraviolet rays in different wavelength regions. SOLUTION: This wavelength separation type ultraviolet receiver is provided with at least two ultraviolet receiving elements, formed by successively laminating a semiconductor layer and an electrode on a conductive substrate surface having sensitivity in different wavelength regions. In this case, those ultraviolet receiving elements are laminated in the ultraviolet receiving element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet ray receiver capable of simultaneously separating and measuring ultraviolet rays in different wavelength ranges.

[0002]

2. Description of the Related Art In recent years, one of the greatest environmental problems on the earth is that the amount of ultraviolet rays on the ground due to the destruction of the ozone layer is increasing. Such ultraviolet rays have serious effects on health such as skin cancer occurrence, increased photosensitivity due to DNA damage, and photoaging. For this reason, it is necessary to measure ultraviolet rays in a wide range. In particular, as the ozone in the stratosphere decreases, the ultraviolet absorption below 330 nm decreases, and the amount of ultraviolet reaching the ground fluctuates. In particular, it is known that high-energy ultraviolet rays having a wavelength of 320 nm or less, called UV-B, cause DNA destruction or the like and cause various damages to the skin.

[0003] For this reason, it is important to measure the amount of UV-B ultraviolet light from the viewpoint of environmental evaluation. On the other hand, in order to measure ultraviolet light in this wavelength region, a conventional ultraviolet light detecting element using a photodetector is used. Although a bandpass filter is used in a conventional filter, the ordinary filter controls the transmittance by multiple reflection using a multilayer film, and when the filter has a transmission region in a short wavelength region, the secondary light has a long wavelength. There is also a transmission region in the region, and when extracting only the ultraviolet region, another visible light filter had to be used in an overlapping manner, so that the color became black, and the ultraviolet light of a long wavelength could not be transmitted naturally. Also, the wavelength transmission range greatly fluctuates depending on the incident angle, and it has been difficult to accurately measure UV-B ultraviolet rays. Further, in order to reduce the angle dependency, there is a disadvantage that the sensor becomes large because a waveguide is provided on the sensor in order to approach linear incidence.

On the other hand, ultraviolet light having a wavelength longer than 320 nm (or 315 nm) is called UV-A and has an important cosmetic effect such as spots, freckles and wrinkles. Currently, the sunscreen agent used to prevent these ultraviolet rays is UV-
An index of SPF for B and an index of PA for UV-A are used. Thus, UV-B and UV-
It was necessary to measure the amount of two ultraviolet rays at the same time in order to analyze the effect separately for A and to prevent it.
Since the sensor for B and the sensor for UV-A were large, they had to be separately installed and measured separately, and it was not possible to accurately measure the amount of ultraviolet light and its influence under the same conditions. In addition, UV-
B and UV-A could not be measured accurately. In addition, sunlight as an ultraviolet ray source is greatly affected by weather conditions, and forms an omnidirectional ultraviolet environment by scattering and reflection in addition to direct sunlight. In particular, the amount of ultraviolet light on the human body is such that sunlight is a large light source and the person as the object to be irradiated is actively moving. By knowing the ultraviolet radiation that is exposed in daily life when it can be measured,
The way of care can be optimized. However, under various daily conditions UV-A
And direct measurement of UV-B, the conventional sensor has a large and heavy UV detector and cannot measure UV light on the skin. In addition, since the detector has a large incident angle dependency, there is a problem that the ultraviolet rays cannot be measured correctly including the influence of the scattered ultraviolet rays from the whole sky.

In order to separate ultraviolet rays at the same place, an ultraviolet ray sensor is required to have a sensitivity from ultraviolet to visible light.
i, GaP, GaAsP and other photodiodes are formed by a combination of an interference filter that transmits only ultraviolet light and a visible light cut filter, so they usually have a black color and naturally do not transmit ultraviolet light other than the selected wavelength. .
For this reason, simultaneous measurement of long-wavelength ultraviolet light and short-wavelength ultraviolet light in the same place required the separation of the two with a half mirror and a filter and the juxtaposition of each sensor, which required a precise and complicated optical system. .

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and achieve the following objects. That is, an object of the present invention is to provide a low-cost ultraviolet light receiver with a small and simple structure that can simultaneously and stably measure ultraviolet light of different wavelength regions and simultaneously measure it.

[0007]

The above object is achieved by the following means. That is, the present invention provides: <1> two or more ultraviolet light receiving elements each having a sensitivity in a different wavelength region, in which a semiconductor layer and an electrode are sequentially laminated on the surface of a conductive substrate; This is a wavelength-separated ultraviolet light receiver characterized by being stacked in one direction. <2> The wavelength separation type ultraviolet ray receiver according to the above <1>, wherein two of the ultraviolet ray receiving elements are stacked. <3> The wavelength separation type ultraviolet ray receiver according to <2>, wherein the two ultraviolet ray receiving elements are stacked with the conductive substrates facing each other. <4> The wavelength separation type ultraviolet ray receiver according to <2>, wherein the conductive substrates in the two ultraviolet ray receiving elements are integrated. <5> The above-mentioned <1> to <1>, wherein the conductive substrate is composed of an ultraviolet-transparent substrate and a conductive film containing an oxide formed on the surface or both surfaces of the ultraviolet-transparent substrate.
The wavelength separation type ultraviolet ray receiver according to any one of <4>. <6> One of the ultraviolet light receiving elements that receives light first is UV-B
<2> is a short wavelength ultraviolet light receiving element that detects UV-A and transmits UV-A, and the other ultraviolet light receiving element is a long wavelength ultraviolet light receiving element that detects UV-A.
It is a wavelength separation type ultraviolet ray receiver as described in any one of <5>. <7> The wavelength-separated ultraviolet receiver according to <6>, wherein the UV-B and the UV-A are simultaneously separated and received. <8> The area of the light receiving surface of the short wavelength ultraviolet light receiving element is
The wavelength-separated ultraviolet receiver according to the item <6> or <7>, wherein the area is larger than the area of the light-receiving surface of the long-wavelength ultraviolet light-receiving element. <9> UV-B having a wavelength shorter than 315 nm or 320 nm is absorbed between the short-wavelength ultraviolet light receiving element and the long-wavelength ultraviolet light receiving element, and 315 nm or 320 nm.
The wavelength separation type ultraviolet light receiver according to any one of <6> to <8>, further including a filter that transmits longer wavelength UV-A. <10> The semiconductor device according to <1>, wherein the semiconductor layer is a semiconductor layer made of a nitride-based compound semiconductor containing at least one element selected from Group III elements and nitrogen. The wavelength separation type ultraviolet ray receiver according to any one of <9>. <11> The composition of the semiconductor layer in the short wavelength ultraviolet light receiving element is Al _x Ga _{(1- x)} N (0.1 <x <0.8), and the composition of the semiconductor layer in the long wavelength ultraviolet light receiving element is A
a wavelength separating ultraviolet light receiver according to <10>, which is a _{l y Ga (1-y)} N (x> y).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a wavelength separation type ultraviolet ray receiver according to the present invention will be described in detail. The wavelength-separated ultraviolet receiver of the present invention includes two or more ultraviolet light-receiving elements each having a sensitivity in a different wavelength region and having a semiconductor layer and an electrode sequentially laminated on the surface of a conductive substrate, and the ultraviolet light-receiving element includes an ultraviolet ray. They are stacked in the light receiving direction. In the wavelength separation type ultraviolet light receiver of the present invention, since a plurality of elements are stacked, the ultraviolet light reception element that receives light first transmits substantially the wavelength region where the ultraviolet light reception element that receives light later has sensitivity. Element. 420 which is practically hard to see with ultraviolet rays
Refers to a wavelength of nm or less. Long wavelength ultraviolet and short wavelength ultraviolet,
That is, UV-A and UV-B are mainly 310 to 330 n
m is divided into the long wavelength side and the short wavelength side around the center, specifically, the short wavelength side is UV-B (lower limit is about 280 nm) and the long wavelength side is UV-A at 315 nm or 320 nm. (The upper limit is 400 nm). The ultraviolet light receiving direction refers to a direction substantially perpendicular to the light receiving surface of the ultraviolet light receiver.

Hereinafter, the present invention will be described in more detail with reference to the drawings, but is not limited thereto. Note that members having the same functions are denoted by the same reference numerals throughout the drawings. FIG. 1 is a schematic enlarged configuration diagram showing an example of the wavelength separation type ultraviolet light receiver of the present invention. The ultraviolet light receiver shown in FIG. 1 includes a short wavelength ultraviolet light receiving element 110 that detects UV-B and transmits UV-A, and a long wavelength ultraviolet light receiving element 120 that detects UV-A. The long-wavelength ultraviolet light receiving element 120 has a structure in which a semiconductor layer 124 and an electrode 126 are sequentially stacked on the surface of a conductive substrate 122. Similarly, the short-wavelength ultraviolet light receiving element 110 is connected to the conductive substrate 11.
A semiconductor layer 114 and an electrode 116 are sequentially laminated on two surfaces. The long wavelength ultraviolet light receiving element 120 and the short wavelength ultraviolet light receiving element 110 are composed of an electrode 126 in the long wavelength ultraviolet light receiving element 120 and a conductive substrate in the short wavelength ultraviolet light receiving element 110 such that the short wavelength ultraviolet light receiving element 110 receives light first. 112 are laminated so as to face each other. A protection body 140 is provided on the light receiving surface side of the ultraviolet light receiver, that is, on the surface of the short wavelength ultraviolet light receiving element 110 opposite to the surface on which the semiconductor layer 114 of the electrode 116 is provided. here,
Conductive substrate 112 in short wavelength ultraviolet light receiving element 110
Is UV-B shorter than 315 nm or 320 nm
And has a function of transmitting UV-A having a wavelength longer than 315 nm or 320 nm.

In the ultraviolet receiver shown in FIG.
Ultraviolet rays are incident from the 0 side (arrow A), and the short-wavelength ultraviolet light receiving element 110 detects UV-B first. Further, the incident ultraviolet light is absorbed by the conductive substrate 112 in the short-wavelength ultraviolet light receiving element 110, and the UV-B is absorbed.
A is transmitted. Subsequently, the long wavelength ultraviolet light receiving element 120
In, the transmitted UV-A is detected. As described above, since the ultraviolet ray receiver shown in FIG. 1 has a configuration in which ultraviolet ray receiving elements having sensitivities in different wavelength regions are simply overlapped, the UV-B and the UV-A are simultaneously separated and received to accurately receive the light. Stable detection is possible, and the cost is low with a simple structure.

FIG. 2 is a schematic enlarged configuration diagram showing an example of the wavelength separation type ultraviolet light receiver of the present invention. The ultraviolet receiver shown in FIG. 2 is configured such that the long-wavelength ultraviolet light receiving element 120 and the short-wavelength ultraviolet light receiving element 110 are opposed to each other with the conductive substrates 112 and 122 facing each other such that the short-wavelength ultraviolet light receiving element 110 receives light first. Are stacked. Other configurations are the same as those of the ultraviolet receiver shown in FIG. However, any of the conductive substrates 112 and 122 of the short-wavelength ultraviolet light receiving element 110 and the long-wavelength ultraviolet light receiving element 120 has a thickness of 315 nm or 3 nm.
Absorb UV-B shorter than 20 nm and 315 n
It may have a function of transmitting UV-A having a wavelength longer than m or 320 nm.

In the ultraviolet light receiver shown in FIG. 2, since the conductive substrates 112 and 122 are laminated while facing each other,
Since the elements are made of the same material without scratching each other, they can be easily bonded and laminated.

FIG. 3 is a schematic enlarged configuration diagram showing an example of the wavelength separation type ultraviolet ray receiver according to the present invention. The ultraviolet light receiver shown in FIG. 3 has a configuration in which the conductive substrate 122 of the long wavelength ultraviolet light receiving element 120 and the conductive substrate 112 of the short wavelength ultraviolet light receiving element 110 in the ultraviolet light receiver shown in FIG. That is, in the ultraviolet ray receiver shown in FIG.
0, a long-wavelength ultraviolet light receiving element 120, respectively. Other configurations are the same as those of the ultraviolet receiver shown in FIG.

In the ultraviolet ray receiver shown in FIG. 3, the conductive substrate 130 is shared and the manufacturing process can be simplified, so that the configuration can be further reduced, and the configuration is simple and low in cost.

FIG. 4 is a schematic enlarged configuration diagram showing an example of the wavelength separation type ultraviolet light receiver of the present invention. The ultraviolet light receiver shown in FIG. 4 has a configuration in which the short wavelength ultraviolet light receiving element 110 and the long wavelength ultraviolet light receiving element 120 are larger in the ultraviolet light receiver shown in FIG. That is, the ultraviolet light receiver shown in FIG.
In this configuration, the area of the light receiving surface of the short wavelength ultraviolet light receiving element 110 is larger than the area of the light receiving surface of the long wavelength ultraviolet light receiving element.
Other configurations are the same as those of the ultraviolet receiver shown in FIG.

In the ultraviolet light receiver shown in FIG. 4, the area of the light receiving surface of the short wavelength ultraviolet light receiving element 110 is larger than the area of the long wavelength ultraviolet light receiving element 120. The output current of -B can be adjusted to be large.

FIG. 5 is a schematic enlarged configuration diagram showing an example of the wavelength separation type ultraviolet light receiver of the present invention. The ultraviolet light receiver shown in FIG. 5 has a configuration in which the light receiving direction (arrow A) of the ultraviolet light receiver shown in FIG. 1 is reversed. That is, the ultraviolet light receiver shown in FIG. 5 includes a protective body 140 on the surface of the short wavelength ultraviolet light receiving element 110 opposite to the surface on which the semiconductor layer 114 of the conductive substrate is provided.
Is provided. However, the conductive substrate 122 of the long-wavelength ultraviolet light receiving element 120 is not 315 nm or 3
Absorb UV-B shorter than 20 nm and 315 n
It has a function of transmitting UV-A having a wavelength longer than m or 320 nm. Other configurations are the same as those of the ultraviolet receiver shown in FIG.

In the ultraviolet ray receiver shown in FIG. 5, ultraviolet rays are received from the conductive substrate 112 side of the short-wavelength ultraviolet ray receiving element 110, so that the conductive substrate 112 absorbs, for example, visible light and transmits ultraviolet light. Since the filter function can be added to the filter, the size can be further reduced, and the configuration is simple and low cost.

Hereinafter, the above members in FIGS. 1 to 5 will be described. In the following, description may be made while omitting the reference numerals of the respective members. (Ultraviolet light receiving element: short wavelength ultraviolet light receiving element 110, long wavelength ultraviolet light receiving element 120) As ultraviolet light receiving elements, short wavelength ultraviolet light receiving element 110, long wavelength ultraviolet light receiving element 120
May have sensitivity to wavelengths other than the wavelength of ultraviolet light, or may have sensitivity only to ultraviolet light. For example, in the case of having sensitivity to wavelengths other than the wavelength of ultraviolet light, such as a silicon-based ultraviolet light receiving element, a visible light cut filter that cuts visible light noise between the light receiving surface of the ultraviolet light receiver or each of the constituent elements. It is necessary to provide various filters such as an interference filter and a long wavelength cut filter. In this case, the thickness of the ultraviolet ray receiver can be reduced by reducing the thickness of the filter. On the other hand, when sensitivity is provided only to ultraviolet light, it is advantageous because there is no need to provide various filters or the like on the light receiving surface side between the ultraviolet light receiver and each element. However, when a specific ultraviolet wavelength is measured or when the ultraviolet wavelength is changed according to the sensitivity of the semiconductor layer, a slight filter may be provided.
For example, when measuring the amount of ultraviolet light only at the wavelength of the ultraviolet light emitted by a mercury lamp, the ultraviolet light receiving element having a semiconductor layer with short wavelength sensitivity has a filter that transmits only a specific short wavelength ultraviolet region and changes the sensitivity wavelength region. It can be provided between the light receiving surface of the ultraviolet light receiver or each of the constituent elements.
In the case of the configuration shown in FIGS. 1 to 5, the short-wavelength ultraviolet light receiving element 110 needs to transmit long-wavelength ultraviolet light.

Specifically, as the long wavelength ultraviolet light receiving element 120, a combination of a silicon photodiode and a filter for cutting the infrared region from the visible region can be used.
An aP-based element (sensor) and a filter for cutting visible light can be used in combination. As the long-wavelength ultraviolet light receiving element 120 and the short-wavelength ultraviolet light receiving element 110, an ultraviolet light receiving element having sensitivity to only ultraviolet light is particularly preferably used. Examples of such an ultraviolet light receiving element having sensitivity only to ultraviolet light include an element having a semiconductor layer containing SiC, diamond, titanium oxide, zinc oxide, or a nitride-based compound semiconductor. Among them, an element having a semiconductor layer made of a nitride-based compound semiconductor containing at least one element selected from Group III elements (for example, Al, Ga, and In) and nitrogen,
It is preferable that the light receiving wavelength can be freely changed by changing the composition. In particular, among devices having a semiconductor layer made of such a nitride-based compound semiconductor, as described later, those in which the semiconductor layer is made of a non-single-crystal material can increase the area of the light-receiving surface, and Since a configuration that transmits UV-A while having sensitivity to UV-B can be easily manufactured, it is suitably used as the short-wavelength ultraviolet light receiving element 110. Details of the semiconductor layer will be described later.

-Conductive Substrates 112, 122, 130 As the conductive substrates, the conductive substrate 112 of the short-wavelength ultraviolet light receiving element 110 and the conductive substrate 122 of the long-wavelength ultraviolet light receiving element 120 have different structures. Or the same. Each conductive substrate of the ultraviolet ray receiver shown in FIGS. 1 to 5 has transparency, ultraviolet ray transmission or a part of the ultraviolet ray absorption / transmission property as described above, but the ultraviolet ray receiver shown in FIG. The conductive substrate 112 of the short-wavelength ultraviolet light receiving element 110 does not need to have ultraviolet transmittance, and may be opaque. However, in the case of the configuration shown in FIGS. 1 to 5, the short-wavelength ultraviolet light receiving element 110 is
It is necessary to transmit the wavelengths received by 20.

The conductive substrate may be either a substrate itself or a conductive substrate whose surface has been rendered conductive, and it does not matter whether it is crystalline or amorphous. Examples of the conductive substrate in which the substrate itself is conductive include metals such as aluminum, stainless steel, nickel, and chromium, and alloy crystals thereof, Si, GaAs, GaP, GaN, and the like.
Semiconductors such as SiC and ZnO can be given.

The insulating substrate includes a polymer film, glass, quartz, ceramic and the like. The conductive treatment of the insulating substrate can be performed by forming a film of the metal, gold, silver, copper, or the like described in the specific examples of the conductive substrate by an evaporation method, a sputtering method, an ion plating method, or the like.

As described above, the conductive substrate receives ultraviolet light.
Depending on the configuration of the vessel, it has UV transmittance (transparency)
There is a need, but as such an ultraviolet transparent substrate
May be glass, quartz, sapphire, MgO, S
iC, ZnO, LiF, CaF _TwoTransparent inorganic materials, such as
In addition, fluorine resin, polyester, polycarbonate, polycarbonate
Polyethylene, polyethylene terephthalate, epoxy, etc.
A transparent organic resin film or plate, and
Optical fiber, selfoc optical plate, etc.
Can be used.

The ultraviolet-transparent substrate is used as it is if it is electrically conductive, but if it is not electrically conductive, a conductive treatment or formation of an ultraviolet-transparent conductive film is required. The conductive treatment or the formation of the ultraviolet-transparent (transparent) conductive film is performed by using indium tin oxide (IT
O), using an ultraviolet transparent (transparent) conductive material such as zinc oxide, tin oxide, lead oxide, indium oxide, copper iodide,
It is formed by a method such as vapor deposition, ion plating, or sputtering, or by forming a metal such as Al, Ni, Au, or the like as thin as translucent by vapor deposition or sputtering. Further, an oxide semiconductor or the like having an ultraviolet-transmitting property can be preferably used. If the thickness of these ultraviolet-transmissive conductive films is too small, the ultraviolet transmittance increases, but a problem such as an increase in electric resistance may occur. Therefore, the thickness is preferably about 5 nm to 100 nm.

Particularly preferably, the conductive substrate is an ultraviolet-transparent substrate and an oxide (eg, ITO, zinc oxide, tin oxide, lead oxide, indium oxide, oxide semiconductor, etc.) formed on the surface of the ultraviolet-transparent substrate. It is preferable to be composed of an ultraviolet-transmissive conductive film containing the same. Quartz, sapphire, MgO, LiO, CaF can be used as a transparent substrate that transmits UV-B having a wavelength shorter than 315 nm or 320 nm.
₂ can be preferably used. Also, 315n as described above
Glass is suitable as an ultraviolet transmitting (transparent) substrate having a function of absorbing UV-B having a wavelength shorter than m or 320 nm and transmitting UV-A having a wavelength longer than 315 nm or 320 nm. As glass,
Suitable examples include borosilicate glass, lead glass, soda glass, and blue plate glass. In addition, in the case of the conductive substrate 130 of the ultraviolet ray receiver shown in FIG. 3 as the conductive substrate, the ultraviolet transparent conductive film is formed on both surfaces of the ultraviolet transparent substrate.

—Semiconductor Layers 114 and 124 — As described above, the semiconductor layer has the short-wavelength ultraviolet light receiving element 1.
Each of the ten semiconductor layers 114 and the semiconductor layer 124 of the long-wavelength ultraviolet light receiving element 120 may have sensitivity to wavelengths other than the wavelength of ultraviolet light, or may have sensitivity only to ultraviolet light. Specifically, as the semiconductor layer of the long-wavelength ultraviolet light receiving element 120, a silicon-based semiconductor layer can be suitably used in combination with a filter that cuts from the visible region to the infrared region. On the other hand, as the semiconductor layer 114 of the short-wavelength ultraviolet light receiving element 110, a GaP-based semiconductor layer which is sensitive to short wavelengths and transmits red light can be used.
Each of the semiconductor layer 114 of the short-wavelength ultraviolet light receiving element 110 and the semiconductor layer 124 of the long-wavelength ultraviolet light receiving element 120 is particularly preferable, and has a sensitivity to only ultraviolet light, such as SiC, diamond, titanium oxide, zinc oxide, and a nitride compound semiconductor. And most preferably, II.
A semiconductor layer made of a nitride-based compound semiconductor containing nitrogen and at least one element selected from Group I elements (for example, Al, Ga, and In) is preferable.

In the following, Group III elements (IUPAC 198)
A semiconductor layer made of a nitride-based compound semiconductor containing at least one element selected from 13) and nitrogen, according to the 9th edition of the revised inorganic chemical nomenclature, will be specifically described.

The semiconductor layer is made of a group III element (group number 13 according to the revised edition of IUPAC's 1989 inorganic chemical nomenclature).
And at least one element selected from the group consisting of nitrogen and nitrogen, and if necessary, other components. Specific examples of Group III elements include B, Al, Ga, In, and Tl, and are preferably at least one selected from Al, Ga, and In. In particular, the composition of the semiconductor layer 114 in the short wavelength ultraviolet light receiving element 110 is A
It is preferable that l _x Ga _(1-x) N (0.1 <x <0.8), more preferably Al _x Ga _(1-x) N (0.2 <x
<0.6>. On the other hand, the long wavelength ultraviolet light receiving element 120
The composition of the semiconductor layer 124 in Al _y Ga _(1-y)
N (x> y) is preferred.

The semiconductor layer may be non-single crystalline or single crystalline. When it is non-single crystalline, it may be amorphous, microcrystalline, or a mixture thereof. In the case of a crystalline state, the crystal system may be any one of a cubic system and a hexagonal system, or may be a state in which a plurality of crystal systems are mixed. The crystal may be a columnar-grown crystal, a single peak in an X-ray diffraction spectrum, a crystal plane orientation highly oriented, or a single crystal.

When the semiconductor layer is a non-single crystal, the semiconductor layer may contain 0.5 at% to 50 at% of hydrogen, or may contain a one-coordinate halogen element. When the hydrogen content of the semiconductor layer is less than 0.5 at%, bond defects at crystal grain boundaries or bond defects and dangling bonds inside the amorphous phase are eliminated by bonding with hydrogen, and the semiconductor layer is formed in a band. Insufficiently to inactivate the defect level, the coupling defects and the structural defects increase, the dark resistance decreases, and the photosensitivity is lost, so that it may not be possible to function as a practical semiconductor light receiving element.

On the other hand, when the hydrogen content of the semiconductor layer is 50
If it exceeds at%, electrical characteristics may be deteriorated and mechanical properties such as hardness may be reduced. Further, the semiconductor layer is easily oxidized, and the weather resistance may be deteriorated.

Here, the hydrogen content (at%) of the semiconductor layer
Can be measured for absolute value by hydrogen forward scattering (HFS). The hydrogen content can also be estimated by measuring the amount of hydrogen released by heating. Furthermore, in the manufacturing process of the semiconductor light receiving element of the present invention, by forming a similar optical semiconductor layer on an infrared transparent substrate such as silicon and sapphire at the same time as forming the semiconductor layer, the optical semiconductor Can be easily measured.
Note that the hydrogen bonding state is also determined from the infrared absorption spectrum.

The structure of the semiconductor layer containing hydrogen, for example, has no ring-like diffraction pattern as measured by transmission electron diffraction, and has a hazy pattern completely lacking long-range order. A halo pattern in which a ring-shaped diffraction pattern can be seen, and a halo pattern in which a bright spot is seen can be used. In such a semiconductor layer, almost no peak is often obtained in X-ray diffraction measurement for observing a wider range than transmission electron beam diffraction.

In transmission electron beam diffraction measurement, many bright spots are observed together with a ring-like diffraction pattern.
Further, even in the case of only spot-shaped bright spots, in the X-ray diffraction measurement, the peak intensity of the polycrystal or the strongest peak is weaker than that of the single crystal, and other weak peaks of other plane orientations are mixed. In some cases. Further, there is a case where an X-ray diffraction spectrum having almost one plane orientation is shown.

In the measurement of the infrared absorption spectrum of the semiconductor layer containing hydrogen, the bonding peak with hydrogen exists and the III
The half-width of the vibration absorption peak of the bond between the group atom (Al, Ga and In) and the N atom is 150 cm ^-1 or more when the amorphous structure is the main component, and 100 c.
m ⁻¹ or less. Here, the half width is defined as the group III atom and N
This is the width of the absorption band at a value of 1/2 of the maximum intensity of the absorption band composed of a plurality of peaks at the absorption position mainly composed of atomic bonds and the intensity excluding the background.

The size of the microcrystal is 5 nm in diameter.
５5 μm, and can be measured by X-ray diffraction, electron beam diffraction, shape measurement using an electron micrograph of a cross section, or the like.

The extinction coefficient of the semiconductor layer is obtained by measuring the absorption amount with a spectrophotometer and dividing the obtained value by the layer thickness in a natural logarithmic system. 20,000c in order to be regarded as
m ⁻¹ or less is preferable, and 10,000 cm ⁻¹ or less is more preferable. These values are approximately 3.
It corresponds to 0 eV or less.

As a raw material of the semiconductor layer, an organic metal compound containing a group IIIA element, preferably one or more elements selected from Al, Ga and In can be used. As the organometallic compound, for example, a liquid or solid such as trimethyl aluminum, triethyl aluminum, tertiary butyl aluminum, trimethyl gallium, triethyl gallium, tertiary butyl gallium, trimethyl indium, triethyl indium, and tertiary butyl indium are vaporized. It can be used alone or in a mixed state by bubbling with a carrier gas. Examples of the carrier gas include hydrogen, hydrocarbons such as N ₂ , methane and ethane, CF ₄ , C ₂
A halogenated carbon such as F ₆ can be used.

As the nitrogen source, N ₂ , NH ₃ , NF ₃ ,
A gas such as N ₂ H ₄ or methylhydrazine, or a liquid can be used by vaporizing or bubbling with a carrier gas.

In the composition of the semiconductor layer, the relationship between the total amount m of group III elements and the amount n of nitrogen is 0.5: 1.0 ≦
It is preferable that m: n ≦ 1.0: 0.5 is satisfied. If the ratio is out of this range, the portion of the bond between the group III element and the group V element (N) that takes a tetrahedral bond is small, and the number of defects increases. May not function as a good semiconductor layer.

The optical gap of the semiconductor layer can be arbitrarily changed depending on the mixing ratio of the group III element. GaN: H
For example, in the case where it is set to be larger than 3.2 to 3.5 eV, by adding Al, 200 n
It can be increased to a hand gap (for example, 6.5 eV) capable of absorbing the wavelength region of m to 330 nm (having sensitivity in the wavelength region). Also, by adding In, it is possible to change the hand gap that can absorb the wavelength range while each is transparent. For example, by adding In, the hand gap can be changed to about 3.2 eV or less.

Here, the optical gap is obtained from a point obtained by extrapolating a low-energy linear portion from a plot of the square of the wavelength (eV) and the absorption coefficient (αe). Alternatively, a wavelength (eV) having an absorption coefficient of 10,000 cm ^-1 may be used. For the absorption coefficient, use the absorbance excluding the background,
It is determined by measuring the film thickness dependency.

The semiconductor layer can be doped with an element for controlling p and n. The n-type elements that can be doped include Li of the Ia group, Cu, Ag, and A of the Ib group.
u, Mg of group IIa, Zn of group IIb, Si, G of group IVa
e, Sn, Pb, and S, Se, and Te in the VIa group can be used.

The p-type elements that can be doped include Ia
Group Li, Na, K, Ib Group Cu, Ag, Au, IIa
Group Be, Mg, Ca, Sr, Ba, Ra, group IIb Z
n, Cd, Hg, IVa group C, Si, Ge, Sn, P
b, VIa group S, Se, Te, VIb group Cr, Mo,
W, VIIIa group Fe, Co, Ni and the like can be used.

In order to prevent hydrogen in the semiconductor layer from binding to the dopant and inactivating the dopant, it is necessary that hydrogen for passivating the defect level be selectively bonded to the group III element and the nitrogen element rather than the dopant. From this point, Si, Ge, and Sn are particularly preferable as the n-type elements, and Be, Mg, and the like are particularly preferable as the p-type elements.
Ca, Zn, and Sr are preferred.

At the time of doping, for n-type, S
iH_Four, Si_TwoH₆, GeH_Four, GeF _Four, SnH_FourIs the p-type
For use, BeH_Two, BeCl_Two, BeCl_Four, Cyclo
Pentadienyl magnesium, dimethyl calcium, di
Methyl strontium, dimethyl zinc, diethyl zinc
Can be used in a gaseous state. In addition, these elements
Thermal diffusion method, ion implantation method
And other known methods.

By forming a single semiconductor layer, a Schottky-type element can be obtained. Further, by forming a pn diode configuration or a pin configuration, the efficiency can be further improved.

The semiconductor layer may be composed of an n-type or p-type semiconductor layer containing at least one or more of Group IIIA elements (preferably Al, Ga and In) and nitrogen (and hydrogen). Alternatively, a film p ⁺ or n ⁺ layer doped with a higher concentration may be inserted, or a film p ⁻ or n ⁻ layer doped with a lower concentration may be inserted.

The semiconductor layer may have a multilayer structure. In this case, the p-type semiconductor layer, the i-type semiconductor layer, and the n-type semiconductor layer have different Al _x Ga _y In _z (x = 0) for transparency and formation of a barrier.
~ 1.0, y = 0 ~ 1.0, z = 0 ~ 1.0), and may have a composition of Al, Ga, In and N.
Type semiconductor layer, i-type semiconductor layer, and each layer of n-type semiconductor layer is a plurality _{Al x Ga y In z N:} H (x = 0~
1.0, y = 0 to 1.0, z = 0 to 1.0).

Hereinafter, a method for forming a semiconductor layer will be described with reference to FIG. 6, but the method is not limited to this. In the following manufacturing method, an example using at least one of Al, Ga, and In as the group IIIA element will be described.

FIG. 6 is a schematic structural view of a layer forming apparatus 100 for forming a semiconductor layer. The layer forming apparatus 10
0 indicates that the plasma is used as the activating means. As shown in FIG. 6, the layer forming apparatus 100 includes a container 1 that can be evacuated and evacuated, an exhaust port 2, a substrate holder 3, a heater 4 for heating the substrate, a quartz tube 5 connected to the container 1, 6 and
A high-frequency coil 7, a microwave waveguide 8, a quartz tube 5,
6, and gas introduction pipes 11, 12 connected to the quartz tubes 5, 6, respectively.
And

In the layer forming apparatus 100, for example, N ₂ is used as a nitrogen element source, and is introduced into the quartz tube 5 from the gas introduction tube 9. For example, a microwave of 2.45 GHz is supplied to a microwave waveguide 8 connected to a microwave oscillator (not shown) using a magnetron, and a discharge is generated in the quartz tube 5. From another gas inlet pipe 10,
For example, H ₂ is introduced into the quartz tube 6. A high frequency of 13.56 MHz is supplied from a high frequency oscillator (not shown) to the high frequency coil 7 to generate a discharge in the quartz tube 6. By introducing, for example, trimethylgallium from a gas introduction pipe 12 arranged downstream of the discharge space, the substrate holder 3
A semiconductor layer made of gallium nitrogen can be formed (deposited) on the conductive substrate set in the above.

Although the gas introduced from the gas introduction pipe 12 is trimethylgallium, an organic metal compound containing indium and aluminum can be used instead, or they can be mixed. Further, these organometallic compounds may be mixed and introduced from the gas introduction pipe 11, or may be introduced separately.

The temperature of the conductive substrate is 100.degree.
00 ° C is preferred. Generally, when the temperature of the conductive substrate is high
And / or when the flow rate of group III source gas is low
In that case, a microcrystalline semiconductor layer is easily formed. Also,
The temperature of the conductive substrate is lower than 300 ° C.
When the flow rate is low, a microcrystalline semiconductor layer is formed.
Quickly, substrate temperature is higher than 300 ℃ and lower than low temperature condition II
Even when the flow rate of Group I source gas is large, half of the crystallites
A conductor layer is easily formed. Further, for example, H _TwoDischarge
When performed, finer formation of the semiconductor layer than when not performed
Crystallization can proceed.

A gas containing at least one element selected from C, Si, Ge, and Sn, or a gas containing Be,
A gas containing at least one element selected from the group consisting of Mg, Ca, Zn, and Sr is supplied to the downstream side of the discharge space (gas introduction pipe 1).
1 or n from the gas inlet tube 12).
It is possible to obtain an amorphous or microcrystalline nitride semiconductor of any conductivity type such as a p-type and a p-type. When introducing C element, carbon of an organometallic compound may be used depending on conditions.

In the layer forming apparatus 100 as described above,
Active nitrogen or active hydrogen formed by the discharge energy may be controlled independently, or a gas such as NH ₃ containing both nitrogen and hydrogen atoms may be used. H ₂
May be added. Further, a condition under which active hydrogen is liberated from the organometallic compound may be used. In this way, activated group III atoms and nitrogen atoms are present on the conductive substrate in a controlled state, and hydrogen atoms convert methyl and ethyl groups into inert groups such as methane and ethane. In spite of the low temperature, an amorphous or microcrystalline film in which little or no carbon is contained and an extremely small amount of film defects are suppressed can be generated despite the low temperature. Note that the hydrogenated amorphous silicon film uses hydrogen instead of nitrogen, and a gas such as silane, disilane, or trisilane may be used instead of the organic metal gas. Further, it can also be formed using a plasma CVD apparatus.

In the layer forming apparatus 100 as described above,
As the activating means, a high-frequency oscillator, a microwave oscillator, an electrocyclotron resonance method, or a helicon plasma method may be used, one of them may be used, or two or more may be used. Further, both may be microwave oscillators, and both may be high frequency oscillators. In FIG. 6, a high-frequency oscillator and a microwave oscillator are used, but both may be microwave oscillators or both may be high-frequency oscillators. Further, both may use an electrocyclotron resonance method or a helicon plasma method. In the case of high-frequency discharge by a high-frequency oscillator, an induction type or a capacitance type may be used.

When different activating means (exciting means) are used, it is necessary to make it possible to generate a discharge at the same pressure at the same time. May be provided with a pressure difference. Further, when the same pressure is used, if different activating means (exciting means), for example, a microwave oscillator and a high-frequency oscillator are used, the excitation energy of the excited species can be largely changed, which is effective for controlling the film quality. The semiconductor layer can be formed in an atmosphere in which at least hydrogen is activated, such as a reactive evaporation method, ion plating, and reactive sputtering.

The above-described semiconductor layer containing at least one element selected from the group III elements and nitrogen has no sensitivity to visible light, and serves as a protective body for protecting the ultraviolet light receiver. There is no need to provide light-shielding properties, no need for intervening various filters, etc., and excellent heat resistance and stability. Therefore, the material and the configuration can be simplified, the configuration can be easily reduced, and the thickness of the element can be reduced. For this reason, a thin ultraviolet light receiver can be suitably manufactured.

-Electrodes 116 and 126-The electrodes are formed as counter electrodes of the conductive substrate. When light is incident on the electrode from the electrode side, the electrode needs to have transparency. Therefore, as the transparent electrode, a transparent conductive material such as indium tin oxide (ITO), zinc oxide, tin oxide, lead oxide, indium oxide, and copper iodide can be used.
In the case where a material having a short wavelength (320 nm or less) such as -B is used, a metal such as Al, Ni, Au, Ni, Co, and Ag is thinly formed by vapor deposition or sputtering so that ultraviolet (light) is transmitted. Things are used. The thickness of the film is
When the thickness is too small, the light transmittance is large but the electric resistance is high. When the thickness is too large, light does not pass. In addition, when measuring a short wavelength such as UV-B, the electrode is particularly translucent gold.

(Protector 140) The protector protects the ultraviolet light receiving element constituting the ultraviolet light receiver, and is optically, mechanically,
It is chemically protected. For example, when the configured ultraviolet light receiving element has sensitivity to a wavelength other than the wavelength of ultraviolet light, the protective body may serve as a light shielding function (filter). As the material of the protective body, metal, ceramics, glass, plastic, or the like is used. The specific configuration of the protective body is not particularly limited. For example, a protective body (particularly made of metal) in which an ultraviolet light receiving element is fixed and contained by using an adhesive or the like inside a box (housing). A protective member for fixing the ultraviolet ray receiving element on one plate-like member and sealing only the terminal portion of the ultraviolet ray receiving element or resin sealing the whole;
A protective body for holding and fixing the ultraviolet ray receiving element by sandwiching the ultraviolet ray receiving element between two plate-shaped objects; a protective body for opening and fixing the ultraviolet ray receiving element by fixing a predetermined hole; And a protective body that encapsulates the periphery of the ultraviolet light receiving element by resin sealing. In addition, in the case where the ultraviolet ray receiver is installed on the human body, it is preferable to use plastic as the material, in particular, from the viewpoint of the effect on the human body such as allergic skin reaction and the portability. In addition, each conductive substrate may play its role as a protective body.

The protective body may be configured to expose a part of the ultraviolet light receiving element so that the semiconductor layer in the ultraviolet light receiving element receives ultraviolet light. Further, the configuration may be such that the ultraviolet light receiving element is completely enclosed and sealed. In this case, at least the light incident surface of the protection body is formed of a material that transmits ultraviolet light. For example, as a material that transmits ultraviolet rays up to about 300 nm, soda glass, borosilicate glass, or a polymer resin such as acryl or polycarbonate to which no ultraviolet absorber is added can be used. As a material that transmits ultraviolet light having a wavelength of about 200 nm, silica glass, quartz, a polymer resin such as polyethylene or polypropylene, or a film can be used.

There may be a space between the protective body and the ultraviolet light receiving element, and the space may be filled with a resin or the like. When a space is provided between the light receiving element and the ultraviolet light receiving element, nitrogen or Ar
Or a liquid such as oil.

In the wavelength-separated ultraviolet light receiver of the present invention, in the ultraviolet light receiver shown in FIGS. 1 to 5, the conductive substrate has a UV-B having a wavelength shorter than 315 nm or shorter than 320 nm.
Has a function of transmitting UV-A having a wavelength longer than 315 nm or 320 nm, and has a function similar to that of a filter. However, between the short wavelength ultraviolet light receiving element and the long wavelength ultraviolet light receiving element, A filter having a similar function may be separately provided. Further, in the present invention, various filters may be provided according to each measurement wavelength, or the conductive substrate may play the role.

The wavelength-separated type ultraviolet light receiving device of the present invention may take out a signal from the ultraviolet light receiving device constituting the same as a photovoltaic current flowing between the electrodes of the light receiving device, or by applying a voltage to the signal. It can also be extracted as photocurrent. For taking out from the electrode, a conductive adhesive, solder, wire bonding, pressure bonding or pressure welding may be used as the electrode wiring.

[0066]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, these embodiments do not limit the present invention. (Example 1)-Fabrication of UV receiver shown in Fig. 1-Fabrication of long-wavelength UV light receiving element 120-(a) Conductivity of indium tin oxide (ITO) sputtered on a cleaned 0.2 mm borosilicate glass substrate at 1000? The conductive substrate 122 was placed on the substrate holder 3, the inside of the container 1 was evacuated through the exhaust port 2, and then the conductive substrate 122 was heated to 350 ° C. by the heater 4. N ₂ gas is introduced into the gas introduction pipe 9
1000 sccm was introduced into a quartz tube 5 having a diameter of 25 mm, and a microwave of 2.45 GHz was set to an output of 250 W through the microwave waveguide 8, matching was performed with a tuner, and discharge was performed. The reflected wave at this time was 0W.
Quartz tube of the H ₂ gas is 30mm diameter than the gas inlet pipe 10 6
500 sccm was introduced thereinto. 13.56 MHz high frequency output was set to 100W. The reflected wave was 0W. In this state, 0.5 sccm of trimethylgallium (TMGa) vapor kept at 0 ° C. was introduced from a gas introduction pipe 12 through a mass flow controller while bubbling at a pressure of 10 ⁶ Pa using hydrogen as a carrier gas. H ₂ gas was introduced into the cyclopentadienyl magnesium kept at 20 ° C. from the gas introduction pipe 12 at a pressure of 65,000 Pa.
1scc through the mass flow controller
m reaction zone. At this time, the reaction pressure measured by a Baratron vacuum gauge was 0.5 Torr. The film was formed for 30 minutes and a 0.1 μm Mg-doped GaN: H film (semiconductor layer 1
24) was produced.

An Au electrode 126 having a diameter of 3 mm was formed thereon to a thickness of 10 nm by vacuum evaporation. This conductive substrate 12
A 0.1 mm silver wire was adhered to the second ITO film (electrode) and the Au electrode 126 using a conductive paste. This element is Au
The electrode 126 side showed a transmittance of 30%. When light is incident from the Au electrode 126 side, 200 nm to 400
There was photosensitivity in the range of nm. On the other hand, when light is incident from the glass side, there is a sensitivity peak at 340 nm, and 10% of the peak sensitivity is defined as a wavelength range from 320 nm to 40 nm.
There was photosensitivity at 0 nm.

—Preparation of Short-Wavelength Ultraviolet Light-Receiving Element 110— (b) Next, a conductive substrate 112 obtained by sputtering indium tin oxide (ITO) at 1000 ° on a washed 0.2 mm borosilicate glass substrate is placed on the holder 3 and exhausted. After evacuating the inside of the container 1 through the port 2, the conductive substrate 112 was heated to 350 ° C. by the heater 4. N ₂ gas is introduced into the gas introduction pipe 9
1000 sccm was introduced into a quartz tube 5 having a diameter of 25 mm, and a microwave of 2.45 GHz was set to an output of 250 W through the microwave waveguide 8, matching was performed with a tuner, and discharge was performed. The reflected wave at this time was 0W.
The H ₂ gas is a quartz tube 6 having a diameter of 30 mm from the gas introduction tube 10.
500 sccm was introduced thereinto. 13.56 MHz high frequency output was set to 100W. The reflected wave was 0W. In this state, trimethylaluminum (TMGa) vapor held at 0 ° C. from the gas introduction pipe 12 was heated at 50 ° C. simultaneously with 0.2 sccm through a mass flow controller while bubbling with nitrogen as a carrier gas at a pressure of 10 ⁶ Pa. Nitrogen was used as a carrier gas and introduced at 1.0 sccm. Gas inlet pipe 1
H ₂ gas was introduced at a pressure of 65000 Pa into cyclopentadienyl magnesium kept at 20 ° C. from 2 and introduced into a 1 sccm reaction region through a mass flow controller. At this time, the reaction pressure measured by a Baratron vacuum gauge was 0.5 Torr. Film formation is performed for 30 minutes and 0.1 μm
Mg doped Al _0.4 Ga _0.6 N: H film (semiconductor layer 11)
4) was produced.

An Au electrode 116 having a diameter of 3 mm was formed thereon by vacuum evaporation to a thickness of 10 nm. This conductive substrate 11
A 0.1 mm silver wire was adhered to the ITO film (electrode) and the Au electrode 116 in 2 using a conductive paste. This short-wavelength ultraviolet light receiving element had photosensitivity in the range of 200 nm to 330 nm when light was incident from the Au electrode side. 2
320n for 10% range for 20nm peak sensitivity
m or less.

—Preparation of Ultraviolet Receiver— (c) Long Wavelength Ultraviolet Receiver 12 Prepared in (a)
0 and the short-wavelength ultraviolet light receiving element 110 manufactured in (b), the electrode 126 of the long-wavelength ultraviolet light receiving element 120 and the short-wavelength ultraviolet light receiving element 1 like the ultraviolet light receiver shown in FIG.
The ten conductive substrates 112 are accurately overlapped and fixed in the light receiving direction using an epoxy-based adhesive (trade name “Cemedine High Super” manufactured by Cemedine Co., Ltd.). Protective body 1 on top
A synthetic quartz plate having a thickness of 0.5 mm was provided as 40, and a wavelength separation type ultraviolet ray receiver was manufactured.

-Evaluation- When the spectral output was measured using a Xe lamp, the output from the short-wavelength ultraviolet light receiving element 110, which was set to receive light first, was sensitive from 250 nm to 320 nm, while the long-wavelength ultraviolet light was received. The output from device 120 was sensitive from 310 to 400 nm. Note that the output intensity is determined by the spectral light amount distribution of the Xe lamp and the sensitivity of each element. In particular, in the case of the long wavelength ultraviolet light receiving element 120, the absorption of the two Au electrodes 116 and 126 and the conduction in the short wavelength ultraviolet light receiving element 110 Glass Substrate 112 and I
It is determined by the absorption of the TO film.

The output of the short wavelength ultraviolet light receiving element 110 is 30
The peak was at 0 nm, and the output of the long wavelength ultraviolet light receiving element 120 was 330 nm. The output intensity ratio was 1:10. It has been found that this ultraviolet receiver can simultaneously measure the intensity of UV-A and UV-B separately and stably and accurately.

(Example 2) ・ Preparation of UV receiver shown in FIG. 2 —Preparation of UV receiver— Long wavelength UV light receiving element 120 prepared in (a) above,
The short wavelength ultraviolet light receiving element 110 manufactured in (b) is connected to the conductive substrate 122 of the long wavelength ultraviolet light receiving element 120 and the short wavelength ultraviolet light receiving element 1 like the ultraviolet light receiver shown in FIG.
The ten conductive substrates 112 are accurately overlapped and fixed in the light receiving direction using an epoxy-based adhesive (trade name “Cemedine High Super” manufactured by Cemedine Co., Ltd.). Protective body 1 on top
A synthetic quartz plate having a thickness of 0.5 mm was provided as 40, and a wavelength separation type ultraviolet ray receiver was manufactured.

-Evaluation- When the spectral output was measured using a Xe lamp, the output of the short-wavelength ultraviolet light receiving element 110, which was installed so as to receive light first, was sensitive from 250 nm to 320 nm, Output from 320 to 400 nm
There was sensitivity. Note that the output intensity is determined by the spectral light amount distribution of the Xe lamp and the sensitivity of each element. In particular, in the case of the long wavelength ultraviolet light receiving element 120, two Au electrodes 1 are used.
16, 126 and the two conductive substrates 112, 12
2 and the absorption of the ITO film.

The output of the short wavelength ultraviolet light receiving element 110 is 30
The peak was at 0 nm, and the output of the long wavelength ultraviolet light receiving element 120 was 340 nm. The output intensity ratio was 1:15. It has been found that this ultraviolet receiver can simultaneously measure the intensity of UV-A and UV-B separately and stably and accurately.

(Embodiment 3) ・ Preparation of the ultraviolet ray receiver shown in FIG. 4 —Preparation of the ultraviolet ray receiver—
The short wavelength ultraviolet light receiving element 110 manufactured in (b) is connected to the conductive substrate 122 of the long wavelength ultraviolet light receiving element 120 and the short wavelength ultraviolet light receiving element 1 like the ultraviolet light receiver shown in FIG.
The ten conductive substrates 112 are accurately overlapped and fixed in the light receiving direction using an epoxy-based adhesive (trade name “Cemedine High Super” manufactured by Cemedine Co., Ltd.). Protective body 1 on top
A synthetic quartz plate having a thickness of 0.5 mm was provided as 40, and a wavelength separation type ultraviolet ray receiver was manufactured. However, the short wavelength ultraviolet light receiving element 110 used here was the same in manufacturing method, but the size of the Au electrode 116 on the light receiving surface was 8 mm in diameter. The light receiving area is a long wavelength ultraviolet light receiving element 12
0 was about 7 times.

-Evaluation- When the spectral output was measured using a Xe lamp, the output of the short-wavelength ultraviolet light receiving element 110 installed so as to receive light first was sensitive at 250 nm to 320 nm, and the lower long-wavelength ultraviolet light receiving element was lower. The output from was sensitive from 310 to 400 nm. Note that the output intensity is determined by the spectral light amount distribution of the Xe lamp and the sensitivity of each element. In particular, in the case of the long wavelength ultraviolet light receiving element 120, two Au electrodes 11 are used.
6, 126 and the two conductive substrates 112, 122
Is determined by the absorption of the glass substrate and the ITO film. The output of the short wavelength ultraviolet light receiving element 110 is a peak at 300 nm, and the output of the long wavelength ultraviolet light receiving element 120 is 330 nm.
Met. The output intensity ratio was 2: 3. This UV receiver simultaneously separated UV-A and UV-B intensities and measured them stably and accurately, and found that the difference in output intensity from both elements could be reduced.

Example 4 Production of UV Receiver shown in FIG. 3 -Production of UV Receiver- Conductive substrate 1 in which indium tin oxide (ITO) was sputtered on both sides of a 0.2 mm borosilicate glass substrate at 1000 °.
30 on one surface in the same manner as in (a) above.
A GaN film (semiconductor layer 124) is formed, and an AlGaN film (semiconductor layer 11) is formed on the other surface in the same manner as (b).
4) was produced. Next, a 3 mm-diameter A is placed on the film provided on both surfaces of the conductive substrate 130 so as to be exactly overlapped therewith.
Each of u electrodes 116 and 26 was formed to a thickness of 10 nm by vacuum evaporation. Then, a silver wire of 0.1 mm was bonded to the ITO film (electrode) and the Au electrode with a conductive paste. Further, a synthetic quartz plate having a thickness of 0.5 mm is provided as a protective body 140 on the electrode 116 of the short-wavelength ultraviolet light receiving element 110, and the long-wavelength ultraviolet light receiving element 120 and the short-wavelength ultraviolet light receiving element 120 which share one conductive substrate 130 are provided. An integrated UV receiver comprising the element 110 was used.

This integrated UV receiver has a UV-B
When light is incident from the u-electrode 116 side, there is photosensitivity in the range of 200 nm to 330 nm, and for UV-B, there is a sensitivity peak at 340 nm, and when 10% of the peak sensitivity is defined as a wavelength range, the sensitivity falls from 320 nm to 400 nm. There was light sensitivity.

-Evaluation- When the spectral output was measured using a Xe lamp, the output of the short-wavelength ultraviolet light receiving element 110, which was installed so as to receive light first, was sensitive from 250 nm to 320 nm, and was sensitive to the lower long-wavelength ultraviolet light. Output from device is 310 to 400 nm
There was sensitivity. Note that the output intensity is the distribution of the spectral light amount of the Xe lamp, the sensitivity of each element, and in the case of the long wavelength ultraviolet light receiving element 120, the absorption of the two Au electrodes 116 and 126, the glass substrate of one conductive substrate 130, and the ITO film. Is determined by the absorption of

The output of the short wavelength ultraviolet light receiving element 110 is 30
The peak was at 0 nm, and the output of the long-wavelength ultraviolet light receiving element was 330 nm. The output intensity ratio was 1:18.
It has been found that this ultraviolet receiver can simultaneously measure the intensity of UV-A and UV-B separately and stably and accurately.

According to the embodiment, an ultraviolet light receiving element using a nitride-based compound semiconductor layer containing a group III element and nitrogen was laminated, but the ultraviolet light receiver has a small variation due to the incident angle of light, a high precision and a small size. It can be seen that UV-A and UV-B can be measured at the same time. Further, it can be seen that this ultraviolet light receiver is simple and low cost.

[0083]

As described above, according to the present invention, it is possible to provide a low-cost ultraviolet light receiver which can simultaneously separate ultraviolet light of different wavelength ranges, measure stably with high accuracy, and has a small and simple structure. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an example of a wavelength separation type ultraviolet light receiver according to the present invention.

FIG. 2 is a schematic configuration diagram showing another example of the wavelength separation type ultraviolet light receiver of the present invention.

FIG. 3 is a schematic configuration diagram showing another example of the wavelength separation type ultraviolet light receiver of the present invention.

FIG. 4 is a schematic configuration diagram showing another example of the wavelength separation type ultraviolet light receiver of the present invention.

FIG. 5 is a schematic configuration diagram showing another example of the wavelength separation type ultraviolet light receiver of the present invention.

FIG. 6 is a schematic configuration diagram showing an example of a semiconductor layer forming apparatus for manufacturing a semiconductor (non-single-crystal optical semiconductor) containing a IIIA element and nitrogen according to the present invention.

[Explanation of symbols]

 Reference Signs List 100 layer forming apparatus 1 container 2 exhaust port 3 substrate holder 4 substrate heating heater 5 quartz tube 6, 6 quartz tube 7 high frequency coil 8 microwave waveguide 9-12 gas introduction tube 1 110 short wavelength ultraviolet light receiving element 120 long wavelength ultraviolet light Light receiving element 112, 122, 130 Conductive substrate 114, 124 Semiconductor layer 116, 126 Electrode 140 Protector

Claims (11)

[Claims] 1. An ultraviolet light receiving device having a sensitivity in different wavelength regions and comprising at least two ultraviolet light receiving elements formed by sequentially stacking a semiconductor layer and an electrode on the surface of a conductive substrate, wherein the ultraviolet light receiving elements are stacked in an ultraviolet light receiving direction. A wavelength-separated ultraviolet light receiver, comprising: 2. The wavelength-separated ultraviolet receiver according to claim 1, wherein two ultraviolet light-receiving elements are stacked. 3. The wavelength-separated ultraviolet light receiver according to claim 2, wherein the two ultraviolet light receiving elements are stacked with the conductive substrates facing each other. 4. The wavelength-separated ultraviolet light receiver according to claim 2, wherein the conductive substrates of the two ultraviolet light-receiving elements are integrated. 5. The conductive substrate according to claim 1, wherein the conductive substrate comprises an ultraviolet-transparent substrate and a conductive film containing an oxide formed on the surface or both surfaces of the ultraviolet-transparent substrate. The wavelength separation type ultraviolet light receiver according to any one of the above. 6. One of the ultraviolet light receiving elements which receives light first is U
6. A short wavelength ultraviolet light receiving element that detects V-B and transmits UV-A, and the other ultraviolet light receiving element is a long wavelength ultraviolet light receiving element that detects UV-A. The wavelength separation type ultraviolet ray receiver according to any one of the above. 7. The wavelength-separated ultraviolet light receiver according to claim 6, wherein UV-B and UV-A are simultaneously separated and received. 8. The wavelength-separated ultraviolet light receiver according to claim 6, wherein an area of a light receiving surface of the short wavelength ultraviolet light receiving element is larger than an area of a light receiving surface of the long wavelength ultraviolet light receiving element. 9. A UV-B having a wavelength shorter than 315 nm or 320 nm is absorbed between the short-wavelength ultraviolet light receiving element and the long-wavelength ultraviolet light receiving element, and 315 nm or 32 nm.
9. The wavelength-separated ultraviolet light receiver according to claim 6, further comprising a filter that transmits UV-A having a wavelength longer than 0 nm. 10. The semiconductor layer according to claim 1, wherein said semiconductor layer is a nitride-based compound semiconductor containing at least one element selected from Group III elements and nitrogen. 10. The wavelength-separated ultraviolet light receiver according to any one of claims 9 to 9. 11. The half of the short wavelength ultraviolet light receiving element
The composition of the conductor layer is Al _xGa_(1-x)N (0.1 <x <0.
8) The semiconductor layer in the long wavelength ultraviolet light receiving element
The composition is Al_yGa_(1-y)N (x> y)
The wavelength separation type ultraviolet ray receiver according to claim 10.