JPH11195808A - Optical semiconductor element and manufacture therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical semiconductor element using non-monocrystal material which has a freely selectable broad of optical gap, excellent optical conductive characteristics, high speed response, anti-environment characteristics, high temperature resistant characteristics, and is optically active, has a large area and can be a new, low-cost optoelectronic material. SOLUTION: At least a first layer 2 and a second layer 3 having optical gap smaller than that of the first layer 2 are alternately laminated on a substrate 1. Moreover, in an optical semiconductor element having a structural unit made by laminating a third layer having an an optical gap larger than the optical gap of the second layer 3, the first layer 2, the second layer 3 and a third layer 4 respectively comprise non-monocrystal material containing at least one of Al, Ga and In and nitrogen and hydrogen more than 0.5 atm.% but less than 50 atm.%, and the layer thickness of the second layer 3 is 5 to 200 angstrom.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-single-crystal optical semiconductor, a method of manufacturing the same, and an optical semiconductor device using the optical semiconductor.

[0002]

2. Description of the Related Art Conventionally, an amorphous or microcrystalline non-single-crystal optical semiconductor has been used as a photoelectric conversion member for a semiconductor light receiving element. For example, amorphous chalcogenide compounds such as selenium and tellurium are widely used in image pickup tubes, light receiving elements, electrophotographic photoreceptors, and the like (Ohm, “Basics of amorphous semiconductors”). In recent years, hydrogenated amorphous silicon has been used in solar cells, image sensors,
Used for lm Transistor, electrophotographic photoreceptor, etc.

However, conventional non-single-crystal optical semiconductors formed from an amorphous chalcogenide compound or hydrogenated amorphous silicon have various problems. Amorphous chalcogenide compounds are unstable with respect to heat, are easily crystallized, have limited conditions for use, and have drawbacks such as inability to control valence electrons. Hydrogenated amorphous silicon can control valence electrons, can realize a pn junction and an electric field effect at the interface, and has heat resistance up to about 250 ° C. However, there is a phenomenon that photoconductivity is deteriorated by strong light ( Stae
bler-Wronski effect: Applied physics handbook), for example, there is a problem that the efficiency of a solar cell is reduced during use.
In addition, the band gap of amorphous or microcrystalline silicon is about 1.7 eV to 1.5 eV, and Ge or C should be added to effectively use sunlight or to allow sufficient light to reach the active region. Although the band gap can be narrowed or widened by adding these elements, even if these elements are added and changed by about 0.3 eV, there is a problem that the photoconductive property is greatly deteriorated and light in a wide range cannot be used effectively. Further, semiconductors containing elements such as Ge and C have indirect transition type crystals and cannot be used for light-emitting elements, and their applications are limited.

On the other hand, most of III-V group compound semiconductors belong to direct transition type semiconductors, and have a characteristic that the light absorption coefficient is large and the band gap can be changed by the composition. In particular, the nitrogen-based compound is GaN eGaN from 1.9 eV.
Up to 3.2 eV, and up to 6.5 eV of AlN, the band gap can be changed widely from the ultraviolet region to the visible region. Therefore, as a non-single-crystal optical semiconductor whose band gap can be freely set, a group III-V compound, particularly a nitrogen-based II
Expectations have been raised for non-single-crystal optical semiconductors made of IV group compounds.

[0005] Further, a semiconductor comprising a nitrogen-based III-V crystal is generally used as a substrate for a sapphire substrate, a GaAs substrate,
Crystal growth is performed using SiC substrates, but these substrates are expensive and cannot be grown as they are because their lattice constants are not compatible with these semiconductors. Has a disadvantage that it is necessary to insert a buffer layer, perform nitriding of the substrate, and the like. In addition, as for the nitrogen-based III-V crystal substrate material, as a material for inputting / outputting light, a conductive substrate often has insufficient light transmission, while a substrate having good light transmission is used. Was insulative and was insufficient as a substrate for optical semiconductor elements. Also, this crystal growth is usually 800-
Although it is performed at a temperature of 1100 ° C., there is a problem that materials compatible with such a high temperature are limited, and the size of a bulk crystal for a substrate is limited, and a film having an arbitrary large area cannot be obtained. For this reason, nitrogen-based III-V compound crystal LEDs (Light Emitting Diodes)
However, when LEDs are used for two-dimensional display devices such as Display, it is necessary to arrange LEDs by the number of pixels, which is expensive for high-resolution display such as several hundred thousand to several million pixels. There was a problem that the place where it could be used too much was limited. Conventionally, in a display element, a method of arranging pixels of a plurality of colors on one plane has been widely used, and in transmission of high-density information such as high-resolution display and optical interconnection, it is more difficult. Although an element having a light emitting point with a high density is required, when the light emitting elements are arranged, the interval is large, and the displacement and the size of the unit pixel are problems. These luminescence and photoconductivity, photovoltaic,
For a two-dimensional device having a relatively large area using high-speed electron transfer, there has been a demand for an amorphous or microcrystalline material which is not limited in size and can be manufactured at low cost.

In view of the above circumstances, nitrogen-based non-single crystals
III-V compounds have attracted attention as optical semiconductor materials. Conventionally, a non-single-crystal group III-V compound has a manufacturing temperature of
It is obtained by setting the temperature lower than the case of producing crystals (600-1000 ° C). Specifically, a group III-V compound crystal film is formed by vapor deposition or sputtering of a group III-V crystal, or by a reaction between an atomized group III metal and a molecule containing a group V element or an active molecule. [H.Reuter,
H. Schmitt, M. Boffgen, Thin Solid Films, 254 (1995) 9
4] or so-called organometallic CVD using an organometallic compound containing a group III metal and a compound containing a group V element.
Although non-single-crystal group III-V compounds are produced on a heated substrate by the (MOCVD) method, the substrate temperature can be adjusted by these methods when the crystal is produced (600-1000).
C)).

[0007] However, the method in which a crystal is used as a raw material and which is produced by sputtering has many defects in the film and has poor optical semiconductor characteristics such as photoconductivity. Non-single-crystal III-V compound semiconductors that can function as an optical semiconductor material have problems such as low-temperature film formation, carbon from organic metal remaining in the film, and many defect levels in the film. [H.Reute
r, H. Schmitt, M. Boffgen, Thin Solid Films 25 4,94 (199
Five)].

[0008] These amorphous or microcrystalline non-single-crystal III-V compound semiconductors obtained by passivating defects with hydrogen include fine particles containing hydrogen by a plasma CVD method using an organometallic compound as a group III raw material. Crystalline film
Although GaN was obtained, it did not show photoconductivity and was insulating [J. Knights, and RALujan, J. Appl. Phys., 42, 1291
(1978)]. In addition, hydrogenated amorphous GaAs produced by the plasma CVD method has a small photoconductivity of about 10%, which is far from practical. As described above, in order to introduce hydrogen, it is necessary to form a film at a lower temperature.However, in a low-temperature film formation using an organometallic compound as a group III raw material, carbon remains in the film due to a problem. [Y. Segui, F. Ca
rrere and A. Bui, Thin Solid Films, 92, 303 (198
2)].

[0009]

SUMMARY OF THE INVENTION A first object of the present invention is to improve the disadvantages of the above-mentioned nitrogen-based non-single-crystal III-V compound semiconductors, to freely select a wide range of optical gaps, and to obtain excellent photoconductive properties. Using a non-single-crystal material that has high-speed response, environmental resistance and high temperature resistance, is optically active, has a large area, and can be a new low-cost optoelectronic material. An optical semiconductor device is provided. A second object of the present invention is to provide an input / output optical semiconductor element capable of high-resolution display and high-density optical information. A third object of the present invention is to provide a method for manufacturing an optical semiconductor device which can be manufactured safely and at low cost.

[0010]

Means for Solving the Problems The present inventors have developed a conventional nitrogen-based non-single-crystal group III-V compound, such as carbon from an organic metal remaining in a film or having many defect levels in the film. As a result of intensive studies on the improvement of the defects of semiconductor materials, a nitrogen-based non-single-crystal III-V compound semiconductor having a low carbon content and a small number of defects in the film was obtained by using the film forming method of the present invention. A material can be obtained, and it has been found that a high-performance optical semiconductor element can be obtained by using this material, and the present invention has been completed.

That is, in the optical semiconductor device of the present invention, at least a first layer and a second layer having an optical gap smaller than the first layer are alternately laminated on a substrate, and In an optical semiconductor device having a structural unit obtained by laminating a third layer having an optical gap larger than the optical gap, the first layer, the second layer, and the third layer are each made of Al, Ga , In and at least one element and nitrogen
The second layer is formed of a non-single-crystal material containing not less than 0.5 atomic% and not more than 50 atomic% of hydrogen, and has a thickness of 5 to 200 μm.

It is preferable that a p-type intermediate layer and an n-type intermediate layer for current injection are provided on both sides of the structural unit, and the intermediate layer is formed of at least one element of Al, Ga, and In. More preferably, it is made of a non-single-crystal material containing nitrogen, nitrogen and 0.5 to 50 atomic% of hydrogen. Further, in order to facilitate light extraction, at least one of the intermediate layers may be an intermediate layer having an optical gap larger than the optical gap of the second layer, and a transparent electrode may be provided on the intermediate layer. preferable.

Further, an optical semiconductor device comprising two or more of the above structural units laminated on a transparent substrate may be provided. Also in this case, it is preferable to provide a transparent electrode on a transparent substrate in order to facilitate light extraction.

The non-single-crystal material constituting the optical semiconductor device of the present invention has Al, Ga, and In atoms in the infrared absorption spectrum.
The half width of the absorption peak indicating the bonding of N atoms is preferably 300 cm ^-1 or less, and the ratio of the total number x of atoms of Al, Ga, and In to the total number y of atoms of nitrogen is 0.5: 1.0. And more preferably between 1.0 and 0.5.

The n-type intermediate layer may further contain at least one element selected from C, Si, Ge, Sn, and the p-type intermediate layer may include at least one element selected from Be, Mg, Ca, Zn, Sr. It can further include at least one selected element. Further, each intermediate layer is composed of C, S
At least one element selected from i, Ge, Sn and Be, Mg, Ca,
At least one element selected from Zn and Sr can be contained simultaneously.

The non-single-crystal optical semiconductor of the present invention comprises an active species that has activated a compound containing nitrogen and an organometallic compound that contains at least one element of Al, Ga, and In. In the following, it can be produced by reacting. Activated hydrogen may be supplied by activating a compound containing hydrogen, and high-frequency discharge and / or microwave discharge may be used as the activating means.
Further, it is preferable to introduce at least one or more of the organometallic compounds containing a group III element in the periodic table from the downstream side of the activating means.

According to this method, even at a low temperature at which an amorphous film or a microcrystalline film can be grown, the organic groups are separated from the organic metal as stable molecules, are not taken into the film, and unbonded bonds are formed during film growth. Active hydrogen generated from organic groups or separately added hydrogen and active hydrogen due to hydrogen compounds acts to remove carbon on the film surface during film growth, reducing impurities to a very small amount. it can.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. (Structure of Optical Semiconductor Element) FIGS. 1 and 2 are schematic sectional views showing an example of the structure of the optical semiconductor element of the present invention. As shown in FIG. 1, the optical semiconductor device of the present invention is configured such that at least a first layer 2 and a second layer 3 having an optical gap smaller than the first layer are alternately laminated on a substrate 1. It has a structural unit 5 consisting of a third layer 4 having an optical gap greater than or equal to the optical gap of the second layer provided thereon. The structural unit 5 may have a well structure in which the first layer 2 and the second layer 3 are one set, or a multi-well structure in which two or more sets of the first layer 2 and the second layer 3 are stacked. . Further, a p-type intermediate layer 6 and an n-type intermediate layer 7 for current injection may be provided on both sides of the structural unit 5. A transparent electrode 8 is provided on an intermediate layer on the light input / output side (the n-type intermediate layer 7 in FIG. 1) of the p-type intermediate layer 6 and the n-type intermediate layer 7. Alternatively, as shown in FIG. 2, of the p-type intermediate layer 6 and the n-type intermediate layer 7, the transparent electrode 9 is provided on the light-input / output-side intermediate layer (p-type intermediate layer 6 in FIG. 2). And a transparent substrate 10 are provided.

The first layer constituting the active layer of the present invention,
The second layer and the third layer provided on the active layer contain at least one element of Al, Ga, and In, nitrogen, and 0.5 to 50 atomic% of hydrogen, respectively. It is made of a non-single-crystal material.

In the present invention, the term non-single crystal means that it is amorphous or microcrystalline, and it means any of an amorphous phase, a microcrystalline phase, and a mixed state of a microcrystalline phase and an amorphous phase. May be. The crystal system of the microcrystal may be any one of a cubic system and a hexagonal system, or a state in which a plurality of crystal systems are mixed. The size of the microcrystal is 5 nm.
And 5 μm, and can be measured by X-ray diffraction, electron diffraction, shape measurement using an electron micrograph of a cross section, or the like. Here, the term “amorphous” refers to, for example, a halo pattern in which there is no ring-like diffraction pattern in the transmission electron beam diffraction pattern and the halo pattern completely lacks long-range order. , And those in which luminescent spots are seen. In such a film, almost no peak is often obtained in X-ray diffraction measurement for observing a wider range than transmission electron beam diffraction. The microcrystal refers to, for example, a transmission electron beam diffraction pattern in which a large number of bright spots are observed together with a ring-shaped diffraction pattern, or a microcrystal in which only spot-shaped bright spots are observed. In a film composed of microcrystals, in X-ray diffraction measurement, a peak slightly corresponding to a crystal plane is obtained. However, in the case of a polycrystalline film, the peak intensity is weaker than that of a single crystal, and the peak width is single crystal. Often larger than. like this,
By using an amorphous or microcrystalline material, a film can be formed on a free substrate material at a low temperature, so that a high-performance optical semiconductor element can be manufactured at low cost without any limitation in shape and size. Can be.

The non-single-crystal material of the present invention has at least one of Al, Ga and In as a group III element in the periodic table. The optical gap of the film can be arbitrarily changed depending on the mixing ratio of these group III elements. For example, GaN: H
Based on the optical gap of the film, 3.2-3.5 eV,
Can be increased to about 6.5 eV by adding
It can be changed to about 1.9 eV, and it can be used in the visible region.

The non-single-crystal material of the present invention contains nitrogen as a group V element. By selecting nitrogen as the group V element, the composition ratio can easily maintain the stoichiometric state.

When the total number of atoms of Al, Ga, and In in the non-single-crystal material of the present invention is x and the number of atoms of nitrogen is y, the ratio of x to y is 1.0: 0.5 to 1.0. : 2.0. If the ratio of x to y is out of this range, the bond between the group III element and nitrogen will be cubic or zincblende.
The number of parts that take the nde) type is reduced, and as a result, the number of defects increases and the semiconductor does not function as a good semiconductor. The composition of each element in the non-single-crystal material can be measured by a method such as X-ray photoelectron spectroscopy (XPS), electron microprobe, Rutherford back scattering (RBS), or secondary ion mass spectrometer.

The hydrogen concentration in the non-single-crystal material of the present invention is 0.1%.
Must be in the range of 5 atomic% to 50 atomic%.
In order to realize an amorphous structure while maintaining a three-dimensional structure, dangling bonds are generated in both the group III element and nitrogen. Further, in order to realize a three-dimensional structure using microcrystals, dangling bonds are generated in both the group III element and nitrogen at the grain boundaries. In order to compensate for this dangling bond, a one-coordinate atom such as hydrogen or halogen can be used. In the present invention, in order to compensate for such dangling bonds, the hydrogen is bonded to the group III element and the nitrogen together. Therefore, if the non-single-crystal material contains less than 0.5 atomic% of hydrogen, bonding defects at the crystal grain boundaries, bonding defects inside the amorphous phase, and dangling bonds are eliminated by bonding with hydrogen, and the band inside the band is eliminated. Insufficient to inactivate the defect levels formed in the substrate, and as a result of maintaining the coupling defects and structural defects, the dark resistance is reduced and the photosensitivity is lost, so that it functions as a practical photoconductor. Can not do. Further, since the number of recombination centers in the non-radiation process increases, the luminous efficiency decreases, and the device cannot function as a light emitting element. On the other hand, if the amount of hydrogen contained in the non-single-crystal material exceeds 50 atomic%, the probability of hydrogen bonding to two or more group III elements and nitrogen increases, and these elements become 3%.
Instead of maintaining a two-dimensional structure, a two-dimensional and chain-like network is formed. In particular, a large number of voids are generated at the grain boundaries, resulting in the formation of a new level in the band and the electrical characteristics. And mechanical properties such as hardness are reduced. Further, the film is easily oxidized, and as a result, a large amount of impurity defects are generated in the film, so that good photoelectric characteristics cannot be obtained. Further, when the hydrogen contained in the non-single-crystal material exceeds 50 atomic%, the dopant to be doped for controlling the electrical characteristics becomes inactivated by hydrogen, and as a result, the electrically active non-crystalline material becomes inactive. A non-single-crystal optical semiconductor made of crystalline or microcrystalline cannot be obtained. The absolute value of the amount of hydrogen can be measured by hydrogen forward scattering (HFS). It can also be estimated by measuring the amount of hydrogen released by heating or measuring the infrared absorption spectrum.

Hydrogen and a group III element in a non-single crystal material,
The bonding state between hydrogen and nitrogen and between nitrogen and a group III element can be easily measured by infrared absorption spectrum. That is, the state of chemical bonding in the film can be defined mainly by the bonding state of the group III element, nitrogen, and hydrogen, and the quantity relation. Furthermore, the film structure and further the characteristics of the film can be defined by grasping the relationship with carbon as an impurity in a complex manner.

FIG. 3 is a spectrum diagram showing an example of an infrared absorption spectrum of a film formed using a Si wafer as a substrate. Here, since gallium is used as the group III element, according to this spectrum, there is an absorption peak due to skeleton vibration of Ga-N near 550 cm ⁻¹ . From the measurement results,
It has been found that the absorption peak of Ga-N near 550 cm ^-1 exhibits a single and sharp shape as it approaches the amorphous to microcrystalline structure. When compared with the phase state determined from the electron diffraction pattern, specifically, the half width is 25
At 0 cm ^-1 or more, it is amorphous, and when the half width is 200 cm ^-1 or less, the amorphous structure is mainly contained but microcrystals begin to mix, and when the half width is 100 cm ^-1 or less, microcrystals Is known to be the subject. On the other hand, the absorption band at this absorption peak position is, for example, a half width of 300 cm due to a plurality of absorption bands in an organic film containing a large amount of CH bonds and the like.
It is known to spread more than ^-1 .

The non-single-crystal material of the present invention preferably has a low content of carbon and the like, and has a low infrared absorption spectrum.
Al, Ga, the half width of the absorption peak indicating the bond between the In atom and the N atom is preferably 300 cm ^-1 or less, microcrystals,
The more included, the better the photoconductivity and high-speed response. Therefore, the half width of the absorption peak (III-N) of Ga-N is 150 cm.
^-1 or less is more preferable.

In the present invention, the full width at half maximum includes an absorption band composed of a plurality of peaks at an absorption position mainly composed of a bond between a group III atom and nitrogen, and excludes the maximum intensity of the peak and the background. This is the width at the position where the strength is halved. Alternatively, when the low wave number side cannot be completely measured, the half value width of one half of the high wave number side is doubled.

The peak of the absorption wavelength shifts to a higher wave number in the range of 10 to 40 cm ^-1 between the case of amorphous and the case of microcrystal, but the same relationship applies. In addition to gallium as a Group III element, indium,
The same relationship can be applied to the case of an infrared absorption spectrum of a film containing aluminum or the like. For example
When In is added, it shifts to the lower wavenumber side by 10-50 cm ^-1, but the same relation is applied. Absorption peaks due to other bonds also shift depending on the state and the contained elements, but the absorption peak intensity relation is handled in the same manner.

In the non-single-crystal material of the present invention, oxygen and carbon are
It is desirable that the total amount be 15 atomic% or less. When oxygen is contained in the material, this oxygen atom becomes the group III element Al, Ga, In
To form a stable bond with Al, Ga, In, and nitrogen atoms to partially form a two-dimensional flexible structure. In this case, it is difficult to take an electrically active coupling arrangement, and as a result, pn control cannot be performed. On the other hand, when carbon is contained in the material, the bond between carbon and hydrogen is more stable than the bond between Al, Ga, In and hydrogen as Group III atoms, and more hydrogen is bonded to carbon. Carbon is -CH _2- , -C
The generation of likely chain structure and voids take of H ₃ bond can not pn control for structural flexibility when the dopant was doped with defect level increases overall material. Further, in the case of a wide-gap material, the material is colored to change from yellow to brown, so that the optical characteristics are also deteriorated. The concentrations of oxygen and carbon in the film were determined by X-ray photoelectron spectroscopy (XP
S), an electron microprobe, Rutherford back scattering (RBS), a secondary ion mass spectrometer, or the like.

The non-single-crystal material of the present invention can be doped with another element for controlling pn. Elements for n-type include Li of the Ia group, Cu, Ag, Au, and II of the Ib group.
Mg of group a, Zn of group IIb, Si, Ge, Sn, Pb of group IVa, S, Se, Te of group IVb can be used. The p-type elements include Li, Na, K of the Ia group, Cu, Ag, Au of the Ib group, and Be, M of the IIa group.
g, Ca, Sr, Ba, Ra, Zn, Cd, Hg of IIb group, C, Si, Ge, IVa group,
Sn, Pb, IVb group S, Se, Te, VIa group Cr, Mo, W, VIII group Fe, Co, Ni, etc. can be used.

The dopant is preferably one that does not inhibit the bonding of activated hydrogen to the group III element and nitrogen, that is, the passivation of the defect level by the activated hydrogen. In other words, it is necessary that the activated hydrogen selectively binds to the group III element and nitrogen and binds to the dopant so that it is not inactivated. From this point, Si, Ge, and Sn are particularly preferable as the n-type element, and Be, Mg, Ca, Zn, and Sr are particularly preferable as the p-type element.

The optical gap of each layer included in the structural unit of the present invention is preferably in the range of 2.0 to 6.5 eV for the first layer, and the optical gap of the second layer is preferably in the range of 2.0 to 6.5 eV. Although it is smaller than the optical gap of the layer, it is preferably smaller by about 0.1 to 3.0 eV from the viewpoint of forming the quantum well layer,
More preferably, it is smaller by about 0.1 to 2.5 eV. The optical gap of the third layer is equal to or larger than the optical gap of the second layer, and is 0.1 to 3.0 in terms of the wall of the quantum well layer.
It is preferable that it is as large as eV.

The thickness of each of the first layer and the second layer constituting the active layer of the present invention is 5 to 200 °, more preferably 5 to 150 ° from the viewpoint of light emission efficiency. . 5mm thick
In the following, since a quantum well structure cannot be formed, electrons and holes move freely in the bulk and are captured by the non-radiative recombination center. On the other hand, if the layer thickness is more than 200 mm, the width of the quantum well structure is too wide, and the effect of confining electrons and holes in the barrier cannot be obtained. The thickness of the third layer is preferably 5 to 500 ° in view of formation of a quantum well layer and current injection.

Like the first and second layers, the intermediate layer according to the present invention is a non-metal layer containing at least one element of Al, Ga, and In, nitrogen and 0.5 to 50 atomic% of hydrogen. It is preferable to be composed of a single crystal material. Further, it is preferable that at least one of the intermediate layers of the present invention has an optical gap larger than the optical gap of the second layer. Specifically, it is preferable to make the optical gap larger by about 0.1 to 3.0 eV. In this manner, light input or light output can be performed from one of the layers. In addition, the thickness of the intermediate layer of the present invention is preferably 5 ° to 2 μm in terms of light input / output and current injection amount.

The substrate of the present invention may be conductive or insulating, and may be crystalline or amorphous. As the conductive substrate, metals such as aluminum, stainless steel, nickel, chromium and their alloy crystals, Si, GaAs, GaP, GaN, SiC,
A semiconductor such as ZnO can be given. Alternatively, an insulating substrate having a substrate surface subjected to a conductive treatment can be used. As the insulating substrate, polymer film, glass,
Quartz, ceramic and the like can be mentioned. The conductive treatment is performed by forming a film of the above metal, gold, silver, copper, or the like by an evaporation method, a sputtering method, an ion plating method, or the like.
In particular, a substrate that is provided on the side that performs light input and light output is one that is transparent to the wavelength of light that performs light input and light output. Glass, quartz, sapphire, MgO, L
iF, transparent inorganic materials such as CaF _2, also fluorine resin, polyester, polycarbonate, polyethylene, polyethylene terephthalate, film or plate-like body of a transparent organic resin such as epoxy, furthermore, Opti Cal fiber, SELFOC optical plate etc. Can be used.

As the electrode of the present invention, a known electrode can be used. In particular, the electrode provided on the side that performs light input and light output has a wavelength of light that performs light input and light output. Use a transparent one. As the light-transmitting electrode provided on the light-transmitting support, a transparent conductive material such as ITO, zinc oxide, tin oxide, lead oxide, indium oxide, or copper iodide is used, and evaporation, ion plating, sputtering, or the like is used. Or Al, Ni, Au
And the like are formed by vapor deposition or sputtering so as to be thin enough to be translucent.

The optical semiconductor device of the present invention is provided on a transparent substrate.
A structure in which the first layer and the second layer are laminated two or more times may be employed. By stacking these layers two or more times, the reliability of the layer functioning as a quantum well structure is improved,
High efficiency can be achieved. Further, in order to improve the current injection efficiency, a p ⁺ layer or an n ⁺ layer, which is a film with a higher concentration of doping, is provided between the substrate and the first intermediate layer or the second intermediate layer and the electrode. A p ^- layer or n ^- layer, which is a lightly doped film, may be inserted between the first intermediate layer and the first layer or the second intermediate layer and the second layer. You may. Furthermore, these p-type, i-type, and n-type layers are different from each other for transparency and formation of a barrier.
Al, Ga, In represented by Al _x Ga _y In _z (x = 0-1.0, y = 0-1.0, z = 0-1.0)
And N composition, and each of the p-type, i-type, and n-type films has a plurality of Al _x Ga _y In _z N: H (x = 0-1.0, y = 0-1.0, z
= 0-1.0).

(Method of Manufacturing Optical Semiconductor Device) As described above, the optical semiconductor device of the present invention is manufactured by laminating a non-single-crystal material made of amorphous or microcrystalline.
Therefore, a method for manufacturing a non-single-crystal material will be described first.

The non-single-crystal material of the present invention reacts an active species that has activated a compound containing nitrogen with an organometallic compound containing a Group III element in the periodic table in an atmosphere containing activated hydrogen. To form a film on the substrate. The above-described production method is characterized in that an organometallic compound is used as a raw material for a Group III element in the periodic table, and that the reaction with activated nitrogen and hydrogen is performed at a low temperature.

The activation of the nitrogen-containing compound of the present invention means
Bringing the compound containing nitrogen into the energy state required for reaction with the organometallic compound containing a group III element, or
It means that a compound containing nitrogen is decomposed into excited species. In addition, activated hydrogen can be obtained by activating an excited hydrogen gas or by activating a compound containing hydrogen. Examples of the compound containing hydrogen include a hydrogen molecule, a hydrocarbon, a hydrogen halide, and an organometallic compound, and a hydrogen molecule is preferable because impurities are not mixed. The activated hydrogen and activated nitrogen formed by the discharge energy may be controlled independently, or may be activated simultaneously using a gas containing both nitrogen and hydrogen atoms, such as NH ₃ .
In this case, H ₂ may be further 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 substrate in a controlled state, and hydrogen atoms convert methyl and ethyl groups into inert molecules such as methane and ethane. Therefore, despite the low temperature, an amorphous or microcrystalline film with little or no amount of carbon and with reduced film defects can be formed.

As the activating means, a high-frequency discharge, a microwave discharge, an electrocyclotron resonance method, a helicon plasma method, or the like can be used. These activation means may be used alone or in combination of two or more. Further, high frequency discharges, microwave discharges, or electron cyclotron resonance methods may be used in combination. In the case of high-frequency discharge, it may be an induction type or a capacitance type. When different activating means (exciting means) are used, it is necessary to enable simultaneous discharge at the same pressure, and a pressure difference may be provided between the inside of the discharge tube and the film forming unit. When the same pressure is used, when different activating means (exciting means), for example, a microwave and a high-frequency discharge are used, the excitation energy of the excited species can be largely changed, which is effective for controlling the film quality.

The organometallic compound containing a Group III element in the periodic table of the present invention includes trimethylaluminum,
Liquid or solid such as triethyl aluminum, tertiary butyl aluminum, trimethyl gallium, triethyl gallium, tertiary butyl gallium, trimethyl indium, triethyl indium, tertiary butyl indium, etc. are vaporized and mixed alone or by bubbling with a carrier gas Can be used with

The compounds containing nitrogen of the present invention include N
_{2, NH 3, NF 3,} N 2 H 4, a gas such as methylhydrazine,
Liquid nitrogen compounds can be used.

In the non-single-crystal optical semiconductor of the present invention, there are many cases where the raw material or the auxiliary raw material does not contain hydrogen in the reactive evaporation method, ion plating, reactive sputtering, and the like. It can be obtained by performing film formation in an atmosphere of hydrogen that has been performed.

Hereinafter, the method for producing a non-single-crystal material of the present invention will be specifically described together with the production apparatus used. FIG. 4 is a schematic view of an apparatus used for the plasma-activated MOCVD method. The plasma-activated MOCVD method is a method for producing a thin film using plasma as an activating means. In FIG.
Numeral 11 denotes a container which can be evacuated to vacuum, 12 denotes an exhaust port, 13 denotes a substrate holder, 14 denotes a heater for heating the substrate, 15, 16
Is a quartz tube connected to the container 11 and communicates with the gas introduction tubes 19 and 20, respectively. Further, a gas introduction tube 22 is connected to the quartz tube 15, and a gas introduction tube 22 is connected to the quartz tube 16.

In this apparatus, for example, N ₂ is used as a nitrogen source and introduced into the quartz tube 15 from the gas introduction tube 19. A microwave of 2.45 GHz is supplied to a micro waveguide 18 connected to a microwave oscillator (not shown) using a magnetron to generate a discharge in the quartz tube 15. Thereby, N ₂ is activated, and the active species is introduced into the container 11. From another gas inlet 20, as a hydrogen element source,
For example, H ₂ is introduced into the quartz tube 16. A high frequency of 13.56 MHz is supplied to a high frequency coil 17 from a high frequency oscillator (not shown) to generate a discharge in the quartz tube 16. Thereby, H ₂ is activated, and the active species is introduced into the container 11. By introducing trimethylgallium from the gas introduction pipe 22 from the downstream side of the discharge space, the activated species that has activated nitrogen, the activated species that has activated hydrogen, and trimethylgallium react with each other, and hydrogen is deposited on the substrate. An amorphous or microcrystalline non-single-crystal gallium nitride optical semiconductor can be formed.

Whether the non-single-crystal material of the present invention becomes amorphous or microcrystalline depends on conditions such as the type of substrate, substrate temperature, gas flow rate / pressure, discharge output and the like. Further, the composition of the non-single-crystal material that determines the value of the optical gap depends on the concentrations and flow rates of the source gas and the carrier gas. The film thickness is
It depends not only on the concentration and flow rate of the source gas and the carrier gas, but also on the energy of the discharge. However, regarding the control of the film thickness,
It is preferable to control the film formation time.

As for the type of the substrate, in the case of a crystalline substrate or a crystalline substrate whose surface has been subjected to etching treatment, it tends to become microcrystalline. For example, a Si substrate or the like can be suitably used. In addition, the substrate temperature is set to 100 ° C. for non-single crystal.
To 600 ° C. is preferable, and when the substrate temperature is higher than 300 ° C., microcrystals are easily formed, which is preferable.

Various raw material gases are introduced from a gas inlet, and as a carrier gas, hydrocarbons such as hydrogen, N ₂ , methane and ethane, and halogenated carbons such as CF ₄ and C ₂ F ₆ are used. be able to. The substantial flow rate of the source gas is preferably 0.001 to 10 sccm from the viewpoint of film quality and the like. When the flow rate of the group III source gas is small, microcrystals are easily formed, which is preferable. However, the influence of the substrate temperature on the substrate temperature and the flow rate of the group III raw material gas is more significant. When the substrate temperature is higher than 300 ° C., even when the flow rate of the group III raw material gas is large, microcrystals are easily formed. On the other hand, when the flow rate of the group III source gas is large and the discharge output is insufficient, an organic film tends to be formed, which is not preferable.

In particular, the organometallic compound containing a group III element should be placed downstream of the discharge space (in FIG. 3, the gas introduction pipe 11 or the gas introduction pipe 12) in order to avoid film formation in the discharge space.
It is preferable to introduce the gas through the gas introduction pipe provided in the above. Also,
When introducing an organometallic compound containing several Group III elements, they may be introduced from the same gas introduction tube or from different gas introduction tubes.

Further, a gas containing at least one element selected from C, Si, Ge and Sn, or a gas containing at least one element selected from Be, Mg, Ca, Zn and Sr is used. By introduction, an amorphous or microcrystalline nitride semiconductor of any conductivity type such as n-type and p-type can be obtained. C
In this case, carbon of an organometallic compound may be used depending on the conditions. These are preferably introduced from a gas introduction pipe provided on the downstream side of the discharge space, like the organometallic compound containing a group III element.

As the element sources of C, Si, Ge and Sn, SiH ₄ , Si ₂
Compounds such as H ₆ , GeH ₄ , GeF ₄ , SnH ₄ are converted to Be, Mg, Ca, Zn,
Elemental sources of Sr include BeH ₂ , BeCl ₂ , BeCl ₄ , biscyclopentadienyl magnesium, dimethyl calcium,
Compounds such as dimethylstrontium, dimethylzinc and diethylzinc can be used in a gaseous state. As a doping method, a known method such as a thermal diffusion method or an ion implantation method can be employed.

When the discharge output is high, microcrystals are apt to be formed. For example, when a film is formed using active hydrogen by hydrogen discharge in combination with the active film, microcrystallization is performed more than when no film is formed. Is preferred.

Next, a method of manufacturing the optical semiconductor device of the present invention shown in FIG. 1 will be described. A first intermediate layer 6 made of a p-type (or n-type) non-single-crystal optical semiconductor is provided on the conductive or conductive-processed substrate 1 by using the plasma-activated MOCVD method described above. , A first layer 2 made of a non-single crystal containing at least one element of Ga, In, nitrogen and hydrogen, and a first layer 2 containing at least one element of Al, Ga, In, nitrogen and hydrogen. The source gas is alternately switched between the first layer and the second layer 3 made of a non-single crystal having a smaller optical gap than a single layer for a certain period of time, or the discharge of two discharges that does not contain nitrogen atoms is turned on / off. Depending on 5 ~ 100
Laminate one or more sets with a thickness of Å. As described above, the composition and thickness of these layers may be controlled by changing the concentrations of the source gas and the carrier gas, by changing the flow rate, or by changing the discharge energy. It is preferable to control the film thickness by controlling the film forming time. On top of this,
A third layer 4 made of the same non-single crystal as the first layer is laminated, and a second intermediate layer 7 made of an n-type (or p-type) non-single-crystal optical semiconductor is formed on the third layer 4. The transparent electrode 8 is laminated on the second intermediate layer 7.

[0056]

EXAMPLE 1 Using a manufacturing apparatus shown in FIG. 2, a cleaned Al substrate, a quartz substrate, and a Si wafer were placed on a substrate holder 13 and an exhaust port 12 was formed.
After the inside of the container 11 was evacuated through, the substrate was heated to 250 ° C. by the heater. N ₂ gas is introduced from the gas introduction pipe 19 into the quartz tube 15 having a diameter of 25 mm at 1000 sccm, and a microwave of 2.45 GHz is output through the microwave waveguide 18 at 250 W.
, And matching was performed with a tuner to discharge.
The reflected wave at this time was 0W. Hydrogen gas is gas inlet pipe 2
100 sccm was introduced into a quartz tube 16 having a diameter of 30 mm from 0. The microwave output was set to 200W. The reflected wave was 0W. In this state, 1 sccm of trimethylgallium (TMGa) vapor kept at 0 ° C. was directly introduced from the gas introduction pipe 22 through the mass flow controller. At this time, the reaction pressure measured with a Baratron vacuum gauge was 66.5 Pa. 30 depositions
GaN: H film was prepared. Next, 5
Trimethylindium (TMIn) maintained at 0 ° C. was introduced into the 3 sccm reaction region through a mass flow controller at a pressure of 1.01 × 10 ⁵ Pa using nitrogen gas as a carrier gas. The valve of the gas introduction pipe 22 is turned on / off 10 times every 30 seconds, and the GaN: H layer and the GaInN: H layer are
A multilayer structure in which InN: H layers were alternately laminated was produced. From the experiment of another single layer, the thickness of each layer was GaInN: H layer thickness of 30Å, G
The aN: H layer thickness was estimated to be 20Å. Thereafter, a film of only trimethylgallium (TMGa) was formed for 30 minutes while the valve of the gas introduction pipe 22 was closed to produce a GaN: H film, and an optical semiconductor device was obtained.

The composition of the GaN: H film of the obtained optical semiconductor device was measured under the same conditions as that of the GaN: H film by RBS (Rutherford Backscattering), and the stoichiometry was obtained at a Ga / N ratio of 1.0. I was Carbon (C) was less than 5 atomic%, and oxygen (O) could not be detected. Also, the hydrogen content by HFS measurement was 25 atomic%. By IR spectrum measurement, it was confirmed that hydrogen was contained in the GaN film as Ga-H, NH. The Ga-N absorption was found to be broad at 200 cm ^-1 and amorphous. Note that only a halo pattern could be detected in the electron diffraction spectrum, indicating that the sample was amorphous. The optical gap was 3.2 eV. Further, the composition of the film manufactured under the same conditions as the GaInN: H film of the obtained optical semiconductor device was measured using a correction coefficient calibrated from the RBS measurement by XPS, and the Ga / N ratio was 1.0: 0.2.
The ratio with N was almost stoichiometric at (Ga + In) / N ratio 1.1. The optical gap of the single layer was 2.6 eV. When a multilayer film having a quantum well structure of the obtained optical semiconductor device was measured by IR spectrum measurement, it was substantially the same as a single-layer GaN: H film. This film is transparent and the optical gap is 3.0
eV.

At room temperature, He-Cd
When the laser was irradiated with continuous ultraviolet light, a clear green light emission was observed. A semi-transparent gold electrode was deposited for 100 、 and the dark resistance was measured to be 10 ⁺¹⁵ Ωcm. Xenon (X
e) When irradiated with lamp light, the response was 0.1 s or less, the photoconductivity was 6 digits or more, and ultraviolet light could be detected.

COMPARATIVE EXAMPLE 1 The same manufacturing apparatus as in Example 1 was used and set in the same state.
The vapor of trimethylgallium (TMGa) retained at was introduced at 1 sccm directly through a mass flow controller. At this time, the reaction pressure measured with a Baratron vacuum gauge was 66.5 Pa. Trimethylindium (TMIn) kept at 50 ° C. from the gas introduction pipe 22 was introduced into a 3 sccm reaction region through a mass flow controller at a pressure of 1.01 × 10 ⁵ Pa using nitrogen gas as a carrier gas, and a film was formed for 60 minutes. G
An aInN: H film was prepared to obtain an optical semiconductor device.

At room temperature, He-Cd
No emission was observed when the laser was irradiated with continuous ultraviolet light. When a gold electrode was provided and dark resistance was measured
When irradiated with a xenon (Xe) lamp light at 10 ⁺⁹ Ωcm, the response was 1 s or more, and the light-dark ratio was only one digit, indicating photoconductivity.

Comparative Example 2 The same manufacturing apparatus as in Example 1 was used and set in a similar state.
The vapor of trimethylgallium (TMGa) retained at was introduced at 1 sccm directly through a mass flow controller. At this time, the reaction pressure measured with a Baratron vacuum gauge was 66.5 Pa. Film formation was performed for 60 minutes to produce a GaInN: H film, and an optical semiconductor device was obtained.

At room temperature, He-Cd
Irradiation with continuous ultraviolet light from the laser showed no light emission including the ultraviolet region. When the dark resistance was measured, it was 10 ⁺¹⁵ Ωcm. When irradiated with a xenon (Xe) lamp, the response was 0.1 s or less, and the photoconductivity was four orders of magnitude.

COMPARATIVE EXAMPLE 3 The same manufacturing apparatus as in Example 1 was used and set in a similar state.
The vapor of trimethylgallium (TMGa) retained at was introduced at 1 sccm directly through a mass flow controller. At this time, the reaction pressure measured with a Baratron vacuum gauge was 66.5 Pa. Film formation was performed for 30 minutes to produce a GaN: H film. Next, trimethyl indium (T
MIn), using nitrogen gas as carrier gas, pressure 1.01
× 10 ⁵ Pa, 3sccm through mass flow controller
Introduced into the reaction area, and formed a film continuously for 5 minutes.
An H film was prepared. The estimated thickness is 300 mm. Thereafter, with the valve of the gas introduction pipe 22 closed, trimethylgallium (T
MGa) alone to form a GaN: H film for 30 minutes to obtain an optical semiconductor device.

The obtained optical semiconductor device was transparent and showed an interference color. When the obtained optical semiconductor element was irradiated with continuous ultraviolet light of a He-Cd laser at room temperature, no light emission was observed. The dark resistance was measured to be 10 ⁺⁹ Ωcm, and when irradiated with a xenon (Xe) lamp light, the response was 1 s or more and the photoconductivity showed only one digit of the light-dark ratio.

Example 2 Using the manufacturing apparatus shown in FIG. 2, a cleaned Al substrate, a quartz substrate, and a Si wafer were placed on a substrate holder 13 and an exhaust port 12
After evacuation of the inside of the container 11 through, the substrate was heated to 350 ° C. by the heater. N ₂ gas was introduced into the quartz tube 5 having a diameter of 25 mm from the gas introduction tube 19 at a flow rate of 1000 sccm, and a microwave of 2.45 GHz was set to an output of 300 W via the microwave waveguide 18. The reflected wave at this time was 0W. Hydrogen gas is introduced into the gas introduction pipe 20
100 sccm was introduced into a quartz tube 16 having a diameter of 30 mm. The microwave output was set to 200W. The reflected wave was 0W. In this state, nitrogen at a pressure of 1.01 × 10 ⁵ Pa was introduced into trimethylgallium (TMGa) kept at −10 ° C. from the gas introduction pipe 22 and directly passed through a mass flow controller for 2 seconds.
ccm introduced. At this time, the reaction pressure measured with a Baratron vacuum gauge was 66.5 Pa. Film formation was performed for 30 minutes to produce a GaN: H film. Next, trimethylindium (TMIn) kept at 50 ° C. was introduced into the 2 sccm reaction region from the gas introduction tube 22 through a mass flow controller at a pressure of 1.01 × 10 ⁵ Pa using nitrogen gas as a carrier gas. The valve of the gas introduction pipe 22 is turned on / off 10 times every 30 seconds, and the GaInN: H layer is
A multilayer structure in which GaN: H layers and GaInN: H layers were alternately laminated so as to have 0 layers was produced. The thickness of each layer was estimated from the experiment of another single layer to be 20N for the GaInN: H layer and 15Å for the GaN: H layer. Thereafter, a film of only trimethylgallium (TMGa) was formed for 30 minutes while the valve of the gas introduction pipe 22 was closed to produce a GaN: H film, and an optical semiconductor device was obtained.

The composition of the GaN: H film of the obtained optical semiconductor device was measured under the same conditions as the GaN: H film by RBS (Rutherford Backscattering), and the stoichiometry was obtained at a Ga / N ratio of 0.9. I was Carbon (C) was less than 12 atomic%, and oxygen (O) could not be detected. Also, the hydrogen content by HFS measurement was 25 atomic%. By IR spectrum measurement, it was confirmed that hydrogen was contained in the GaN film as Ga-H, NH. In addition, it was found that the Ga-N absorption was sharp and the half width was 70 cm ⁻¹ , indicating that it was microcrystalline. In the electron diffraction spectrum, a clear bright spot was observed in addition to the halo pattern. Further, in the X-ray diffraction measurement, a plurality of diffraction peaks could be measured. Optical Gap was 3.0 eV. Further, the composition of the film manufactured under the same conditions as the GaInN: H film of the obtained optical semiconductor device was measured using a correction coefficient calibrated from the RBS measurement by XPS, and the Ga / N ratio was 1.0: 0.22.
The ratio with N was almost stoichiometric at (Ga + In) / N ratio of 1.0. The optical gap of the single layer was 2.45 eV. The multilayer film having the quantum well structure of the obtained optical semiconductor device was measured by IR spectrum measurement.
There was no change with the membrane. This film is transparent and the optical gap is
3.0 eV.

The obtained optical semiconductor device was subjected to He-Cd
When the laser was irradiated with continuous ultraviolet light, clear emission of green color was observed, and it was found that light emission required for current injection light emission was obtained. Furthermore, it was found that UV-visible light conversion was possible. When the dark resistance was measured, 10 ⁺⁹ Ω
When irradiated with a xenon (Xe) lamp, the response was 5 s or less, the photoconductivity was 2 digits or more, and ultraviolet light could be detected.

Example 3 When introducing trimethylindium (TMIn), the valve of the gas introduction pipe 22 was turned on / off every 15 seconds, and the GaN: H layer was
Other than producing a multilayer structure in which N: H layers are alternately laminated,
An optical semiconductor device was obtained in the same manner as in Example 2. From the experiment of another single layer, the thickness of each layer was estimated to be 10Å for the GaInN: H layer and 10Å for the GaN: H layer.

The obtained optical semiconductor device has a GaN: H film and GaInN: H film.
The film composition and the optical gap were the same as those in Example 2, and the optical gap of the multilayer film having the quantum well structure was 3.0 eV.

The obtained optical semiconductor device was transparent and showed an interference color. When the obtained optical semiconductor element was irradiated with continuous ultraviolet light of a He-Cd laser at room temperature, a clear blue light emission was observed, and it was found that light emission required for current injection light emission was obtained. Furthermore, it was found that UV-visible light conversion was possible. When the dark resistance was measured, it was 10 ⁺⁹ Ωcm, and when irradiated with a xenon (Xe) lamp light, the response was
It showed photoconductivity of 2 digits or more in brightness ratio of 5 seconds or less, and it was possible to detect ultraviolet light.

Example 4 When introducing trimethylindium (TMIn), the valve of the gas introduction pipe 22 was turned on / off every 100 seconds, and the GaN: H layer was
Other than producing a multilayer structure in which nN: H layers are alternately laminated,
An optical semiconductor device was obtained in the same manner as in Example 1. GaInN: H
Layer and GaN: H layer thicknesses of 100
推定 estimated.

The obtained optical semiconductor device has a GaN: H film and GaInN: H film.
The film composition and the optical gap were the same as those in Example 1, and the optical gap of the multilayer film having the quantum well structure was 3.0 eV.

The obtained optical semiconductor device was transparent and showed an interference color. When the obtained optical semiconductor device was irradiated with continuous ultraviolet light of a He-Cd laser at room temperature, clear green emission was observed, and it was found that light emission required for current injection emission was obtained. Furthermore, it was found that UV-visible light conversion was possible. The dark resistance was measured to be 10 ⁺¹⁵
Ωcm, and when irradiated with xenon (Xe) lamp light,
The response showed a photoconductivity of 5 digits or more in light-dark ratio, and it was possible to detect ultraviolet light.

COMPARATIVE EXAMPLE 4 When introducing trimethylindium (TMIn), the valve of the gas introduction pipe 22 was turned on / off every two seconds, and the GaN: H layer was
Other than producing a multilayer structure in which N: H layers are alternately laminated,
An optical semiconductor device was obtained in the same manner as in Example 2. GaInN: H
The thickness of the layer and the GaN: H layer were determined to be 2 mm each from another single layer experiment.
It was estimated.

The obtained optical semiconductor device was transparent and showed an interference color. When the obtained optical semiconductor element was irradiated with continuous ultraviolet light of a He-Cd laser at room temperature, no light emission was observed.

COMPARATIVE EXAMPLE 5 When introducing trimethylindium (TMIn), the valve of the gas introduction pipe 22 was turned on / off five times every 5 minutes, and the GaN: An optical semiconductor device was obtained in the same manner as in Example 2, except that a multilayer structure in which layers of H and layers of GaInN: H were alternately laminated. The thickness of the GaInN: H layer and the thickness of the GaN: H layer were each estimated to be 300 mm from another single-layer experiment.

The obtained optical semiconductor device was transparent and showed an interference color. When the obtained optical semiconductor element was irradiated with continuous ultraviolet light of a He-Cd laser at room temperature, no light emission was observed.

Example 5 The valve of the gas introduction pipe 22 was opened, trimethylindium (TMIn) was introduced for 30 seconds, and only a single layer of GaInN: H was formed, and a layer of GaN: H and a layer of GaInN: H were formed. An optical semiconductor device was obtained in the same manner as in Example 1, except that a structure in which were alternately laminated was prepared. The thickness of each layer was determined by GaInN: H
It was estimated that the layer thickness was 30 ° and the GaN: H layer thickness was 20 °.

The obtained optical semiconductor device has a GaN: H film, GaInN: H
The composition of the film and the optical gap were the same as in Example 1.

The obtained optical semiconductor device was subjected to He-Cd
When the continuous ultraviolet light of the laser was irradiated with the continuous ultraviolet light of the He-Cd laser, clear emission of green color was observed, and it was found that light emission required for current injection emission was obtained. Furthermore, it was found that UV-visible light conversion was possible.

Embodiment 6 Using the same apparatus and the same substrate as in Embodiment 1,
Heated the substrate to 250 ° C. Gas inlet pipe for nitrogen gas
Introduce 1000 sccm into the quartz tube 5 with a diameter of 25 mm from 19
2.45 GHz microwave output through the waveguide 18
Set to 50W, match with a tuner and discharge
Was. The reflected wave at this time was 0W. Hydrogen gas is introduced
100 sccm is introduced into the quartz tube 16 having a diameter of 30 mm from the tube 20.
Was. The microwave output was set to 200W. 0W reflected wave
Met. In this state, the temperature is maintained at 0 ° C. through the gas introduction pipe 21.
Mass flow of trapped trimethylgallium (TMGa) vapor
4 sccm was introduced through the controller. This time balat
The reaction pressure measured by a Ron vacuum gauge was 66.5 Pa. Film formation
For 10 minutes to produce a GaN: H film. Then keep at -10 ° C
1sccm by adding steam of trimethylaluminum (TMA)
Introduced. Hold for 30 seconds under these conditions, and then
The valve is closed and the trimethyl
Nitrogen gas at a pressure of 1.01 × 10 ^Five Led by Pa
1cm reaction area through the mass flow controller
Introduced to the region. This operation is repeated 5 times every 30 seconds,
AlGaN: H layer and GaInN: H layer so that there are five N: H layers
Were alternately laminated to produce a multilayer structure. In addition, AlGa
One layer of N: H was laminated. The thickness of this layer is different for single layer experiments
From the above, it was estimated that the AlGaN: H layer thickness was 30 mm and the GaInN: H layer thickness was 25 mm.
Was. Thereafter, trimming is performed while the valve of the gas introduction pipe 22 is closed.
Perform GaN: H film by forming film with tilgallium (TMGa) for 30 minutes
Thus, an optical semiconductor device was obtained.

The film composition of AlGaN: H of the obtained optical semiconductor device was found to be almost equal to stoichiometric at (Al + Ga) / N ratio of 1.05. The optical gap was 3.8 eV. The composition of the GaInN: H film was (Ga + In) / N 2 ratio 0.95, and the optical gap was 2.8 eV. The optical gap of the multilayer film having the quantum well structure was 3.2 eV.

When the obtained optical semiconductor device was irradiated with ultraviolet light of 337.1 nm of a nitrogen laser at room temperature, a clear orange emission was observed. Further, when the continuous ultraviolet light of the He-Cd laser was applied, a clear orange emission was observed, and it was found that the emission required for the current injection emission was obtained. Furthermore, it was found that UV-visible light conversion was possible. The dark resistance was measured to be 10 ⁺¹⁵
Ωcm, and when irradiated with xenon (Xe) lamp light,
The response showed a photoconductivity of 4 digits or more in light-dark ratio, and detection of ultraviolet light was possible.

Example 7 Using the same apparatus as in Example 2, the same substrate and an ITO substrate, a nitrogen gas was introduced at 1000 sccm from the gas introduction pipe 19, and 2.45 GHz.
Was discharged at a microwave output of 300W. Further, 300 sccm of H ₂ gas was introduced from the gas introduction tube 20, and discharge was performed at a high frequency of 13.56 MHz and an output of 200W. The temperature of the substrate holder was set to 250 ° C. by the heater 14 and in this state, 0.5 sccm of trimethylgallium and 0.1
% Of SiH ₄ was introduced to form an n-type Ga _x N _z : H film. Next, when introducing trimethylindium (TMIn), except that the flow rate of trimethylindium was reduced by half, the GaN: H
And GaInN: H layers were alternately laminated to produce a multilayer structure. The thickness of each layer was estimated from a single-layer experiment to be GaInN: H layer thickness 30Å and GaN: H layer thickness 20Å. Then trimethylgallium (TMGa) and bispentadienyl magnesium
Hold at 50 ° C and 10
Sccm was introduced, and p-type GaN: H was formed for 5 minutes. After cooling, it was taken out of the vacuum chamber, and an Al film was deposited as an electrode using a vacuum evaporator to obtain an optical semiconductor device.

The composition of the GaN: H film of the obtained optical semiconductor device was 0.95 Ga / N ratio, and the optical gap was 3.1 eV. GaI
The composition of the nN: H film is (Ga + In) / N ratio 1.0, and the optical gap is
It was 2.75 eV. The optical gap of the multilayer optical device having the quantum well structure was 3.0 eV.

The obtained optical semiconductor device was replaced with an ITO electrode and gold.
When 10 V was applied to the (Au) electrode, green light emission was observed.

Comparative Example 6 Example 1 differs from Example 1 in that the substrate temperature was 150 ° C., the output of two microwaves was 100 W, and the flow rate of trimethylgallium (TMGa) was 3 s.
The film was formed under the same conditions except that ccm was set and the flow rate of trimethylindium (TMIn) was set to 5 sccm. The GaN: H film had a hydrogen concentration of 40 atomic% and a Ga / N ratio of 1.20. Also, GaIn
The N: H film has a hydrogen concentration of 55 atomic% and a (Ga + In) / N ratio of 1.
Was 3. The estimated thickness of each of these multilayers is 50 mm and 7
It was estimated to be 0Å. The film appeared clear and slightly yellowish. When this film was irradiated with continuous ultraviolet light from a He-Cd laser at room temperature, no light emission was observed. When a gold electrode was vapor-deposited and the photoconductivity was measured, the photoconductivity was less than one order of magnitude.

From the above Examples and Comparative Examples, the optical semiconductor device of the present invention has a laminated structure as in the present invention, exhibits a light emitting function in a wide wavelength range, and has improved photoconductive characteristics and high-speed response. It turns out that it is excellent. On the other hand, the active layer
It can be seen that the photosemiconductor element made of a single material exhibits photoconductive properties but cannot exhibit a light emitting function (Comparative Examples 1 and 2). Further, when the thickness of each layer of the active layer exceeds 200 °, no light emitting function is exhibited and no photoconductive property is exhibited (Comparative Examples 3 and 5). Also, when the layer thickness of each layer of the active layer is smaller than 5 °, it can be seen that no light emitting function is exhibited and no photoconductive property is exhibited (Comparative Example 4). Further, it is found that the light emitting function cannot be exhibited when the layer has a layer containing more than 50 atomic% of hydrogen (Comparative Example 6).

[0089]

The amorphous or microcrystalline optical semiconductor device of the present invention has a light emitting function in the entire wavelength region which is not provided by a conventional amorphous or microcrystalline non-single-crystal semiconductor. The input and light output are variable in the entire range from red to ultraviolet. In addition, it has excellent light resistance, heat resistance, and oxidation resistance, and is capable of high-speed response. In addition, because of its high light transmission, high light sensitivity, and high-speed response, it is also used for hybrid devices that combine electronic and light-emitting devices. it can. Furthermore, in addition to the optical semiconductor element alone, a tandem type in which optical semiconductor elements having different optical input and optical output wavelengths are sequentially combined can effectively utilize a wide range of light from the visible to the ultraviolet region, and provide an optical input. In addition, wavelength multiplexing of light and optical output becomes possible, and the amount of information that can be handled at the same time can be drastically increased.

Specifically, high-efficiency solar cells, high-speed TFTs,
Devices that use electrons, photoconductivity and photovoltaic power, such as electrophotographic photoreceptors, high-sensitivity photosensors, and high-sensitivity avalanche photosensors; devices that use light emission such as large-area LEDs, displays, and full-color flat displays; Devices related to light input and light output, such as modulators, light-to-light wavelength conversion devices, and devices for optical interconnects, as well as composite devices having these functions in combination.

As described above, according to the present invention, a wide range of optical gaps can be freely selected, and an optically active light emitting device having excellent photoconductive properties, high-speed response, environmental resistance and high temperature resistance. An optical semiconductor device using a large-sized and inexpensive new optoelectronic material is also provided. Further, according to the present invention, there is provided a method of manufacturing an optical semiconductor device, which can manufacture the optical semiconductor device of the present invention safely and at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of the structure of an optical semiconductor device of the present invention.

FIG. 2 is a schematic sectional view showing an example of the structure of the optical semiconductor device of the present invention.

FIG. 3 is a spectrum diagram showing an example of an IR spectrum of a film formed using a Si wafer as a substrate.

FIG. 4 is a schematic view of an apparatus used for a plasma activated MOCVD method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 1st layer 3 2nd layer 4 3rd layer 5 Structural unit 6 p-type intermediate layer 7 n-type intermediate layer 8, 9 Transparent electrode 10 Transparent substrate 11 Vacuum container 12 Exhaust port 13 Substrate holder 14 Heater 15 , 16 Quartz tube 17 High frequency coil 18 Micro waveguide 19-22 Gas introduction tube

Claims (17)

[Claims] At least a first layer and a second layer having an optical gap smaller than the first layer are alternately laminated on a substrate, and further have an optical gap larger than the optical gap of the second layer. In an optical semiconductor device having a structural unit in which a third layer is stacked, the first layer, the second layer, and the third layer are each at least one element of Al, Ga, and In. The second layer is made of a non-single-crystal material containing nitrogen and not less than 0.5 atomic% and not more than 50 atomic% of hydrogen.
An optical semiconductor device having a thickness of up to 200 mm. 2. A p-type intermediate layer and an n-type intermediate layer on both sides of the structural unit.
A mold intermediate layer, wherein the intermediate layer is made of a non-single-crystal material containing at least one element of Al, Ga, In, nitrogen and 0.5 to 50 atomic% of hydrogen. The optical semiconductor device according to claim 1. 3. The optical semiconductor device according to claim 2, wherein at least one intermediate layer having an optical gap larger than the optical gap of the second layer is provided as the intermediate layer. 4. The optical semiconductor device according to claim 3, wherein a transparent electrode is laminated on an intermediate layer having an optical gap wider than the optical gap of the second layer. 5. The optical semiconductor device according to claim 1, wherein two or more of the structural units are laminated on a transparent substrate. 6. The optical semiconductor device according to claim 5, wherein a transparent electrode is laminated on the transparent substrate. 7. The infrared absorption spectrum of the non-single-crystal material, wherein a half width of an absorption peak indicating a bond between an Al, Ga, In atom and an N atom is 300 cm ⁻¹ or less. The optical semiconductor device according to any one of items 1 to 6. 8. The ratio of the total number x of atoms of Al, Ga, and In of the non-single-crystal material to the total number y of atoms of nitrogen is 0.5: 1.0.
The optical semiconductor device according to claim 1, wherein the ratio is between 1.0: 0.5. 9. The light according to claim 2, wherein the n-type intermediate layer further contains at least one element selected from C, Si, Ge, and Sn. Semiconductor element. 10. The method according to claim 2, wherein the p-type intermediate layer further contains at least one element selected from Be, Mg, Ca, Zn, and Sr. Optical semiconductor device. 11. The intermediate layer simultaneously contains at least one element selected from C, Si, Ge, Sn and at least one element selected from Be, Mg, Ca, Zn, Sr. The optical semiconductor device according to any one of claims 2 to 9, wherein: 12. The method for manufacturing an optical semiconductor device according to claim 1, wherein each layer is formed using an organometallic compound as a raw material. Manufacturing method. 13. The method for manufacturing an optical semiconductor device according to claim 1, wherein the layer made of the non-single-crystal material is at least one selected from Al, Ga, and In. A method for manufacturing an optical semiconductor device, wherein the method is formed using an organometallic compound containing two elements as a raw material. 14. The production of an optical semiconductor device according to claim 13, wherein an active species obtained by activating the compound containing nitrogen is reacted with an organometallic compound containing an element of Al, Ga, and In. Method. 15. An active species obtained by activating a compound containing nitrogen and an organometallic compound containing an element of Al, Ga, and In are reacted in an atmosphere containing activated hydrogen. Item 15. The method for producing an optical semiconductor device according to item 13 or 14. 16. The method according to claim 14, wherein a high-frequency discharge and / or a microwave discharge is used as the activating means.
16. The method for manufacturing an optical semiconductor device according to item 15. 17. The method for manufacturing an optical semiconductor device according to claim 16, wherein at least one of the compounds containing Al, Ga, and In is introduced from a downstream side of the activating means.