JPH11154763A - Phtoreceiver, flame sensor, and manufacture of light receiving element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an InAlGa-based light receiving element with good quantum efficiency and high speed of response. SOLUTION: A photoreceiver includes a photoreceiver part (PR) made up of a high resistance Iny Alx Ga1-x-y N single crystal film 5 with carrier density of 1×10<15> cm<-3> or below, where x>=0, y>=0, between a semiconductor layer FL of first conductivity type and a semiconductor layer SL of second conductivity type other than the first conductivity type. Then, a pair of electrodes 8a and 8b are formed for providing continuity between the semiconductor layer FL and the semiconductor layer SL.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a light receiving element, a flame sensor using the light receiving element, and a method for manufacturing the light receiving element.

[0002]

2. Description of the Related Art A light-receiving element used for detecting light utilizes a property of a semiconductor in which an electron-hole pair is generated by the energy of incident light, and has a different conductivity type, that is, p-type.
A so-called pn junction type light receiving element in which a type and an n type semiconductor layer are bonded is well known. As a semiconductor material constituting such a light receiving element, Si or the like is generally used,
InAlGaN-based materials are also expected as materials for detecting light having a relatively short wavelength.

[0003]

SUMMARY OF THE INVENTION However, InA
When a pn-junction type light receiving element is made of an lGaN-based material, sufficient performance in terms of quantum efficiency and response speed cannot be obtained. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an InAlGaN-based light receiving device having good quantum efficiency and response speed.

[0004]

According to the first aspect of the present invention, a semiconductor layer of a first conductivity type is provided between a semiconductor layer of a second conductivity type having a different conductivity type from the semiconductor layer of the first conductivity type. , High resistance I having a carrier concentration of 1 × 10 ¹⁵ cm ⁻³ or less
An n _y Al _x Ga _1-xy N single crystal film (x ≧ 0, y ≧ 0) is formed to constitute a light receiving portion, and the light receiving portion is formed by the first conductive type semiconductor layer and the second conductive type semiconductor layer. A pair of electrodes are formed so as to be energized therebetween, thereby forming a light receiving element. That is, the inventors of the present invention set the carrier concentration to 1 in the In _y Al _x Ga _1-xy N single crystal film (x ≧ 0, y ≧ 0).
It was experimentally found that it could be less than × 10 ¹⁵ cm ^-3 ,
Utilizing the high-resistance In _y Al _x Ga _1-xy N single crystal film, a semiconductor layer of the first conductivity type and a semiconductor of the second conductivity type having a different conductivity type from the semiconductor layer between the layers, it became possible that by positioning the _{in y Al x Ga 1-xy} N single crystal film having a high resistance to produce a so-called PIN-type light receiving element. By configuring the light receiving element as a PIN type light receiving element, a high-resistance In _y Al _x Ga _1-xy
Provided is an InAlGaN-based light-receiving element having good quantum efficiency and response speed, in which electron-hole pairs generated by incident light in an N single crystal film can be efficiently and rapidly taken out to a pair of electrodes by an applied electric field. I can do it. Since the In _y Al _x Ga _1-xy N single crystal film can have a sufficiently high resistance, the high resistance In _y Al
by applying a sufficiently high voltage to _x Ga _1-xy N single crystal film,
A so-called avalanche photodiode (APD) can also be used.

[0005] Further, by providing the structure of the second aspect, in the light receiving element of the first aspect, the high-resistance In _y Al _x Ga _1-xy N single crystal film is formed of a group V element I
The material supply ratio to Group II element is set to 5000 or more and M
A light receiving element is formed by film formation by the OCVD method. That is, it can be experimentally confirmed that the carrier concentration of the In _y Al _x Ga _1-xy N single crystal film (x ≧ 0, y ≧ 0) can be sufficiently reduced under these film forming conditions.
Thus, it became possible to produce a type light receiving element or an APD.

According to the third aspect of the present invention, in the light receiving element according to the first or second aspect,
Configured long wavelength edge of the absorption spectrum of _{In y Al x Ga 1-xy} N single crystal film of the high resistance is less 300nm vicinity. Such a wavelength region is a special wavelength out of the visible light region, and light to be detected is generally weak in many cases. In such a case, it is extremely effective to obtain good quantum efficiency and response speed as described above.

[0007] Further, by providing the configuration of the fourth aspect, in the light receiving element according to claim 1 or 2, _{wherein, In y Al x Ga 1-} xy N single crystal film of the high resistance, 0 ≦ y
<0.5 and 0 ≦ x ≦ 0.6. By producing the high-resistance In _y Al _x Ga _{1 -xy} N single crystal film so as to have a composition ratio in such a range, the light receiving material having no sensitivity in the visible light region and having sensitivity in the ultraviolet region. Although an element can be manufactured, such a wavelength region is a special wavelength out of the visible light region, and the light to be detected is generally weak in many cases. In such a case, it is extremely effective to obtain good quantum efficiency and response speed as described above.

The light-receiving device according to any one of claims 1 to 4, wherein the semiconductor layer of the first conductivity type and the semiconductor of the second conductivity type are provided. Each of the layers is composed of a plurality of layers having different carrier concentrations, and the plurality of layers are composed of the high-resistance In _y A
The structure is such that a layer closer to the l _x Ga _1-xy N single crystal film has a lower carrier concentration. With this configuration, it is possible to suppress the flow of carriers from an adjacent layer into the high-resistance InyAlxGa1-xyN single-crystal film, thereby ensuring that the depletion layer spreads in the high-resistance layer. it can.

In the light receiving device according to any one of claims 1 to 5, the semiconductor device according to any one of claims 1 to 5, wherein the first conductive type semiconductor layer and the high resistance I
An n _y Al _x Ga _{1 -xy} N single crystal film and the semiconductor layer of the second conductivity type are formed on an AlN buffer layer laminated on a single crystal substrate to form a light receiving element. That is, the above-mentioned layers constituting the light receiving section are formed on the single crystal substrate, but are not formed directly on the single crystal substrate, but are formed on the AlN buffer layer laminated on the single crystal substrate. Is formed on the substrate. By stacking the layers constituting the light receiving section via the AlN buffer layer in this way, the mismatch of the lattice constant with the substrate side is reduced, and the above layers are stacked on the AIN buffer layer having a flat growth surface. be able to.

In addition, by providing the configuration according to the seventh aspect, a flame sensor is configured using the light receiving element according to the third or fourth aspect. That is, as described above, the flame sensor can be constituted by a light receiving element having no sensitivity in the visible light region and having sensitivity in the ultraviolet region. Regarding the detection of the presence of a flame, the presence or absence of the flame can be detected by detecting the light emitted from the flame, but in this case, if the light from a light source other than the flame is detected, the presence or absence of the flame is erroneously detected. Will be. In general, sunlight and fluorescent lamps can be considered as light that causes such erroneous detection. Here, FIG.
As shown in Fig. 5, when the spectrum of the flame to be detected is compared with the spectra of sunlight and a fluorescent lamp (shown as "indoor light" in Fig. 5), the spectrum of the flame has a certain intensity below 300nm. In contrast, sunlight and fluorescent lamps have a sufficiently small relative intensity.

Therefore, by configuring the flame sensor using a light receiving element having no sensitivity in the visible light region and having a sensitivity in the ultraviolet region, the presence or absence of a flame can be eliminated by excluding disturbance light such as sunlight and fluorescent lights. Can be detected. In this case, the thickness is preferably 300 nm or less in a room where the influence of a fluorescent lamp is mainly considered, and is preferably 280 nm or less in an outdoor where sunlight is considered. Moreover, when the temperature of the flame sensor rises due to the heat of the flame to be measured, the dark current generally increases. However, as described above, the PIN-type light receiving element can be configured to reduce the dark current. Deterioration of detection capability due to an increase can be suppressed as much as possible.

Further, by providing the structure of claim 8, a semiconductor layer of the first conductivity type, a high-resistance In _y Al _x Ga _1-xy N single crystal film, and In the method for manufacturing a light-receiving element, a semiconductor layer of a second conductivity type different from the first conductivity type is sequentially stacked.
The high-resistance In _y Al _x Ga _1-xy N single crystal film is
The film is formed by MOCVD with the material supply ratio of the group III element to the group III element being 5000 or more. It has been experimentally confirmed that the carrier concentration of the In _y Al _x Ga _{1 -xyN} single crystal film can be reduced to about 1 × 10 ¹⁵ cm ⁻³ or less by forming the film in this manner. Thereby, InAlGa having good quantum efficiency and response speed is obtained.
An N-type light receiving element can be provided.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the light receiving element of the present invention will be described below with reference to the drawings. The light receiving element PS is shown in FIG.
As shown in, AlN buffer layer 2 on the sapphire substrate 1 is a single crystal ^{_{substrate, n + In y Al x Ga}} 1-xy N single crystal film ^{_{3, n - In y Al x}} Ga 1-xy N single crystal film 4, high-resistance In _y Al _x Ga _1-xy N single crystal film 5, p ^- In _y
Al _x Ga _1-xy N single crystal film 6, p ⁺ In _y Al _x Ga
_{A 1-xy} N single crystal film 7 is laminated, and n ⁺ In _y Al _x Ga
_{On the 1-xy} N single crystal film 3 and p ⁺ In _y Al _x Ga _1-xy N
A pair of electrodes 8a and 8b are formed on the single crystal film 7, and a high resistance region HR is formed on the periphery of each layer.

That is, the first conductivity type semiconductor layer FL is formed.
N⁺In_yAl_xGa_1-xyN single crystal film 3 and n^-
In_yAl_xGa_1-xyN single crystal film 4 and second conductivity type
P as the semiconductor layer SL^-In_yAl_xGa_1-xyN only
Crystal film 6 and p⁺In_yAl _xGa_1-xyN single crystal film 7
Between the high resistance In_yAl_xGa_1-xyN single crystal film
5 to form a light receiving portion PR, and a semiconductor of the first conductivity type.
Electric current is applied between the body layer FL and the semiconductor layer SL of the second conductivity type.
A pair of electrodes 8a and 8b are formed as described above. or,
As is clear from the notation of the conductivity type, the semiconductor of the first conductivity type is used.
In either the body layer FL or the semiconductor layer SL of the second conductivity type
Is also composed of two layers with different carrier concentrations,
In_yAl_xGa_1-xyThe layer closer to the N single crystal film 5 has
The rear concentration is configured to be low. this
In such an element configuration, each layer constituting the light receiving portion PR
Among them, mainly high-resistance In_yAl_xGa_1-xyN single crystal
The film 5 contributes to generation of electron-hole pairs due to incident light. still,
The light receiving element PS is configured as a so-called PIN type light receiving element
And when it is configured as a so-called APD
However, the difference between the two in terms of element configuration is
High resistance In_yAl_xGa_1-xyOf the thickness of the N single crystal film 5
It is only.

The spectral sensitivity of the light receiving unit PR having the above configuration is as follows.
It is defined by the composition ratio of the group III element of the In _y Al _x Ga _1-xy N single crystal constituting the light receiving portion PR. Specifically, as shown in FIG. 2, the band gap becomes wider as the Al mixed crystal ratio becomes larger, as in the relationship between the band gap of Al _x Ga ₁ -xN not containing In and the Al mixed crystal ratio x shown in FIG. The absorption edge moves to the shorter wavelength side. In _y Al _x Ga in which a part of Al of Al _x Ga _1-x N replaces In
_In the case of _1-xy N, the band gap becomes narrower and the light absorption edge moves to the longer wavelength side as the ratio of replacing In with Al or Ga increases. In the present invention, the light receiving element PS is used as a flame sensor. As described above, the spectrum of light emitted from the gas flame shown as “gas flame light” in FIG. It is desirable that detection can be performed in a state excluding the influence of sunlight acting as light or indoor light (light of a fluorescent lamp).

Therefore, the long wavelength end of the absorption spectrum is 3
It is preferable that the thickness be around 00 nm or less. Specifically, Al _x Ga _{1 -x} containing no In with y = 0
In the case of N, if the Al mixed crystal ratio is selected in the range of 0.33 to 0.35, the band gap is approximately 4.5 eV, and the long wavelength end of the absorption spectrum is approximately 275 nm. When In is included in the component with y> 0, the above band gap can be obtained by increasing the Al mixed crystal ratio x and reducing the gallium ratio accordingly. However, in the range of y ≧ 0.5, even if the ratio of Al is maximized, the long wavelength end of the absorption spectrum moves too much to the long wavelength side, and in reality, the range of 0 ≦ y <0.5 is satisfied. desirable. On the other hand, if the Al mixed crystal ratio x is too large, the sensitivity to “gas flame light” shown in FIG. 5 also decreases, making it difficult to use as a flame sensor. It is desirable that In addition, if it is assumed that the device is used in a room where sunlight is completely shielded, the band gap is set to approximately 4.3 eV, and even if the absorption edge is slightly moved to the longer wavelength side, almost the same value is obtained. Performance is obtained.

Next, a method for manufacturing the light receiving element PS having the above configuration will be described. Each layer constituting the light receiving element PS is stacked on the sapphire substrate 1 in a wafer state by an MOCVD apparatus. As the MOCVD apparatus, a normal pressure type reactor in which a reaction chamber (film formation chamber) is near normal pressure is used. The lamination of each of the above-mentioned layers is performed by putting the sapphire substrate 1 in a wafer state into a reaction chamber (film formation chamber).
In this state, the sapphire substrate 1 is heated, and the supply states of the material gases of the respective constituent elements are sequentially switched, whereby the layers are sequentially laminated. The substrate temperature of the sapphire substrate 1 is 400 ° C. to 600 ° C. during the growth of the AIN buffer layer 2, and 900 ° C. during the growth of the above layers on the AIN buffer layer 2.
１1100 ° C. (most preferably 1050 ° C.). As the material gas, the constituent elements of In, Al, Ga and N are TMIn (trimethylindium) and TMA, respectively.
1 (trimethylaluminum), TMGa (trimethylgallium) and NH ₃ (ammonia),
Further, Si is used as an n-type impurity, and Mg is used as a p-type impurity.
_They are appropriately supplied as SiH ₄ (silane) and CP ₂ Mg (cyclopentane magnesium), respectively. When Ca is used as an impurity, so-called ion implantation is used.

In the lamination of the above layers, the AlN buffer layer 2
Grows to a layer thickness of about 200 ° and n ⁺In_yAl_xGa
_1-xyThe N single crystal film 3 is made of SiH_FourCarry while flowing gas
A concentration is about 1 × 10¹⁸cm^-3Grown to a layer thickness of about 3μm
Let n^-In_yAl_xGa_{1- xy}The N single crystal film 4 is made of SiH
_FourCarrier concentration is about 1 × 10 while flowing gas¹⁷cm ^-3
 To grow to a layer thickness of about 0.1 μm. The product of these layers
Other film forming conditions for the layer are the same as in a known method.
Note that n⁺In_yAl_xGa_1-xyThe layer thickness of the N single crystal film 3 is
Preferably, the thickness is 2 μm or more.
3 μm as shown in FIG.

The high resistance In_yAl_xGa_1-xyN only
When the crystal film 5 is laminated, TMIn, TMA
1, TMGa and NH_ThreeThe material supply amount of each is a (m
ol / sec), b (mol / sec), c (mol / sec)
sec) and X (mol / sec), group V elements
Of the material supply to the group III element, ie, X /
(A + b + c) is set to be 5000 or more
Form a film. By forming a film under such conditions, In
_yAl_xGa_1-xyThe N single crystal film 5 has a carrier concentration of 1
× 10^Fifteencm^-3The following high-resistance single crystal film was obtained,
As an example, a GaN single crystal film is formed with x = 0 and y = 0.
5 × 10 ¹³cm^-3The following carrier concentration
Is obtained. In addition, high resistance In_yAl_xGa
_1-xyWhen forming the N single crystal film 5 as necessary,
Using Si, Mg or Ca as impurities
The density may be adjusted. In addition, the atmospheric pressure type MOCVD equipment
Therefore, it is extremely good to form the film under the above film forming conditions.
Good characteristics can be obtained, but it is not necessarily normal pressure type
Not limited to the above, using a so-called reduced pressure type MOCVD apparatus
Is also good. In a reduced pressure type MOCVD apparatus, In_yAl
_xGa_1-xyThe pressure at the time of forming the N single crystal film 5 is 1/3 to 1
/ 2 atm, group V element with respect to group III element
The material supply ratio can be easily set to a high value as described above.
You.

The thickness of the high-resistance In _y Al _x Ga _{1 -xy} N single crystal film 5 is 0.1 μm when the light receiving element PS is a PIN type light receiving element and 0 when the light receiving element PS is an APD. 0.5 μm. The reason why the layer thickness is increased in the case of the APD is to prevent the electric field intensity in the film from being excessively increased when a high voltage is applied to the APD. However, if the layer thickness of the high-resistance In _y Al _x Ga _1-xy N single crystal film 5 is too large, it is necessary to keep in mind that the response speed is reduced. Speed is obtained.

After the formation of the high resistance In _y Al _x Ga _{1 -xy} N single crystal film 5, the p ^- In _y Al _x Ga _{1 -xy} N single crystal film 6 has a carrier concentration of about ₂ while flowing CP ₂ Mg. 1x1
It is grown to a layer thickness of about 0.1 μm at 0 ¹⁷ cm ⁻³ and p ⁺ In
_The yAl _x Ga _1-xy N single crystal film 7 has a carrier concentration of about 0.3 × 10 ¹⁸ cm ^-3 and about 0.3 μm while flowing CP ₂ Mg.
To a layer thickness of After stacking the above layers, 7
The activation treatment is performed by heating at 00 ° C. for 10 minutes, and further, the high resistance treatment is performed to form the above-described high resistance region HR. This resistance increasing process is performed by ion implantation using hydrogen ions, and hydrogen ions are implanted in a region IP shown by oblique lines in a thickness direction of the wafer in a thickness direction of the wafer in FIG. Depth implanted, as shown in FIG. ^{_{1, n - In y Al x}} Ga 1-xy
The depth reaches the N single crystal film 4.

[0022] Thereafter, as shown in FIG. 4, performs a photo-etching process to strip the implanted's partial hydrogen ions to ^{_{n + In y Al x Ga 1}} -xy N single crystal film 3 depth is exposed, the strip An electrode 8b is formed in a portion corresponding to each light receiving element PS in a portion etched in the same manner, and an electrode 8a is formed in a portion where hydrogen ions are not implanted.
In FIG. 4, a broken line BL indicates a boundary between a region where hydrogen ions are implanted and a region where hydrogen ions are not implanted. The electrode 8a has a two-layer structure of Ni and Au, and has p ⁺ In _y Al _x Ga
_{The 1-xy} N single crystal film 7 side is Ni, while the electrode 8b is T
a two-layer structure of the i and ^{_{Al, n + In y Al x}} Ga 1-xy N
After the single crystal film 3 side is made of Ti and stacked by, for example, electron beam evaporation or various types of sputter evaporation, the electrode 8a is formed in a mesh shape by a lift-off method or chemical etching, and the electrode 8b is formed in a rectangular shape. . Electrodes 8a, 8
After the formation of b, the elements are separated into individual elements along the element separation lines indicated by two-dot chain lines CL in FIG. Note that a heat treatment may be performed after the formation of the electrodes 8a and 8b as needed.

Light receiving element PS manufactured as described above
Is 1 μW /
10% when irradiated with ON / OFF light of cm ²
Rise time from 90% to 90% and 90% to 10%
A fall time of 1 msec or less and a quantum efficiency of about 63% were obtained. Incidentally, the high resistance I
In the PN type light receiving element without the n _y Al _x Ga _1-xy N single crystal film 5, the rise time and the fall time are about 4 times.
The msec and the quantum efficiency are about 55%, and both the response speed and the quantum efficiency are improved. Also, the light receiving element P
When S is configured as an APD, the response speed is P
This is the same as the case of the IN-type light receiving element. When light of 1 μW / cm ² is irradiated, the light receiving area is converted into 1 mm ² ,
A photocurrent of 1 nA or more was obtained. Incidentally, in the PN type light receiving element, a photocurrent of about 100 pA can be obtained under the same conditions.

[Other Embodiments] Hereinafter, other embodiments will be listed. In the above embodiment, the electrode 8a is formed in a mesh shape, but may be formed in a ring shape as shown in FIG. Note that, in FIG. 6, all of the configuration other than the shape of the electrode 8a is the same as in the above embodiment. In the above embodiment, the light to be detected is ^{_{p + In y Al x Ga 1}} -xy through the opening portions of the mesh-like electrode 8a
Although it is configured to be incident on the N single crystal film 7, p ⁺ In _y
On the Al _x Ga _1-xy N single crystal film 7, an AlN anti-reflection film having a thickness equivalent to a quarter wavelength may be formed. Since the material of the antireflection film is made of AlN having a wide band gap, the absorption of the light to be detected by the antireflection film can be suppressed, and the antireflection film is formed to include the antireflection film in a single growth process by MOCVD. It becomes possible.

In the above embodiment, the single crystal substrate 1
The AlN buffer layer 2 is laminated on the
AlGaN may be used as the buffer layer instead of 2
No. Even when AlGaN is used as the buffer layer,
The lattice constant mismatch with the plate side can be reduced.
You. In this case, n⁺In_yAl_xGa_1-xyN single crystal film
3, n^-In_yAl_xGa_1-xyN single crystal film 4, high resistance
In_yAl_xGa_{1- xy}N single crystal film 5, p^-In_yA
l_xGa_1-xyN single crystal film 6, p⁺In_yAl _xGa
_1-xyAl mixed crystal ratio of N single crystal film 7 and AlGaN buffer layer
By setting the difference from the Al mixed crystal ratio to 0.1 or less, high resistance
In_yAl_xGa_1-xyGood crystallinity of N single crystal film 5 etc.
You can do something good.

In the above embodiment, a sapphire substrate is used as the single crystal substrate 1, but, for example, a SiC single crystal substrate may be used instead of the sapphire substrate. In the above-described embodiment, each of the first conductivity type semiconductor layer FL and the second conductivity type semiconductor layer SL has a two-layer configuration with different carrier concentrations, but may each have a single layer configuration. That is, in the above embodiment, n ⁻ In _y A
l _x Ga _1-xy N single crystal film 4 and p ^- In _y Al _x Ga
_{The 1-xy} N single crystal film 6 may be omitted. Further, on the contrary, it constituted by three or more layers, of high resistance _{In y Al x Ga 1-xy} N
It may be configured such that a layer closer to the single crystal film 5 has a lower carrier concentration. In the above embodiment, the first conductivity type is described as n-type, and the second conductivity type is described as p-type. However, this is associated for convenience of description, and the first conductivity type is p-type, The two conductivity types can be described as n-type. Further, in the above-described embodiment, an n-type semiconductor layer is arranged on the side closer to the single crystal substrate 1 to form a PIN type. However, a p-type semiconductor layer is arranged on the side closer to the single crystal substrate 1. May be configured as a PIN type. In the above embodiment, the high-resistance In _y Al _x Ga
MOCV as an apparatus for forming _1-xy N single crystal film 5
Although the D apparatus is illustrated, the film may be formed by, for example, a so-called MBE apparatus. Also in this case, the carrier concentration is set to 1 × 10 ¹⁵ cm by increasing the material supply ratio of the group V element to the group III element as in the above embodiment.
An In _y Al _x Ga _1-xy N single crystal film 5 having a high resistance of ⁻³ or less can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of a light receiving element according to an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a composition ratio and a band gap according to an embodiment of the present invention.

FIG. 3 is a plan view schematically showing a part of the manufacturing process of the light receiving element according to the embodiment of the present invention.

FIG. 4 is a plan view schematically showing a part of the manufacturing process of the light receiving element according to the embodiment of the present invention.

FIG. 5 is a diagram showing a spectrum of gas light and the like.

FIG. 6 is a plan view schematically showing a part of a manufacturing process of a light receiving element according to another embodiment of the present invention.

[Explanation of symbols]

1 single crystal substrate 2 of AlN buffer layer 5 high resistance _{In y Al x Ga 1-xy} N single crystal film 8a, a semiconductor layer of 8b pair of electrodes FL first conductivity type PR receiving portion SL second conductivity type semiconductor layer

Claims (8)

[Claims] 1. A high-resistance semiconductor layer having a carrier concentration of 1 × 10 ¹⁵ cm ⁻³ or less between a semiconductor layer of a first conductivity type and a semiconductor layer of a second conductivity type having a different conductivity type from the semiconductor layer. In _y A
A light receiving portion is formed by forming an l _x Ga _1-xy N single crystal film (x ≧ 0, y ≧ 0), and between the first conductive type semiconductor layer and the second conductive type semiconductor layer. A light receiving element having a pair of electrodes formed so as to be energized. 2. The high-resistance In _y Al _x Ga _1-xy N
2. The light-receiving element according to claim 1, wherein the single crystal film is formed by MOCVD with a material supply ratio of the group V element to the group III element of 5000 or more. According to claim 3 wherein said high-resistance _{In y Al x Ga 1-xy} N
3. The light-receiving element according to claim 1, wherein a long-wavelength end of an absorption spectrum of the single crystal film is set to be around 300 nm or less. 4. The high-resistance In _y Al _x Ga _1-xy N
The light receiving element according to claim 1, wherein the single crystal film is configured to satisfy 0 ≦ y <0.5 and 0 ≦ x ≦ 0.6. 5. The first conductivity type semiconductor layer and the second conductivity type semiconductor layer.
Each of the conductive semiconductor layers is composed of a plurality of layers having different carrier concentrations, and the plurality of layers are composed of the high-resistance In _y Al _x Ga.
_{5. The} method according to claim 1, wherein a layer closer to the _1-xy N single crystal film has a lower carrier concentration.
A light receiving element according to the item. 6. The semiconductor layer of the first conductivity type, the high resistance
In_yAl_xGa _1-xyN single crystal film and the second conductive film
Buffer layer in which a semiconductor layer of the type is laminated on a single crystal substrate
6. The film according to claim 1, wherein the film is formed on
Mounted light receiving element. 7. A flame sensor using the light receiving element according to claim 3. 8. A semiconductor layer of a first conductivity type, a high-resistance In _y Al _x Ga _1-xy N single crystal film on a single crystal substrate, and the semiconductor layer of the first conductivity type is a conductive type. Different second
The conductive semiconductor layer of a sequentially laminated manufacturing method of the light-receiving element, the _{In y Al x Ga 1-xy} N single crystal film of the high resistance, V
A method for manufacturing a light-receiving element in which a material supply ratio of a group III element to a group III element is 5000 or more and a film is formed by MOCVD.