JP3228208B2 - Semiconductor light emitting device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor light emitting device and a method of manufacturing the same, and more particularly, to a semiconductor light emitting device suitable for displaying a large screen image and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a conventional semiconductor light emitting device, a structure using fine particles as an active layer has been used in order to increase luminous efficiency. For example, Japanese Patent Laid-Open No. 4-112584 discloses that
A structure in which semiconductor fine particles are sandwiched between an n-type semiconductor and a p-type semiconductor is shown. Further, as disclosed in JP-A-7-58358 and JP-A-7-58361, light is emitted by sandwiching a quantum box made of fine particles between an electrode and an insulating film. Also, in order to reduce the cost, Japanese Patent Application Laid-Open No. 61-110
As shown in Japanese Patent No. 470, a method of separating a substrate by selective etching has been used.

However, in the above-mentioned conventional technology, since fine particles are used for the active layer, the wavelength is shifted by a slight difference in size, and uniform light emission characteristics cannot be obtained over a wide area. Had problems. In addition, since the fine particles are spherical, it is difficult to form a protective film on the surface of the fine particles, and there is a problem that it is difficult to obtain a high-quality heterointerface necessary for confining carriers. Also,
The method of separating a substrate by selective etching has to support a large area without cracks, and has a problem that it cannot be applied to a light emitting device having a large area.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks of the prior art, and in particular, to effectively confine carriers, achieve high luminous efficiency, excellent reproducibility, and high durability. It is an object of the present invention to provide a novel semiconductor light emitting device capable of increasing the area and a method for manufacturing the same.

[0005]

SUMMARY OF THE INVENTION The present invention basically employs the following technical configuration to achieve the above object. That is, the first embodiment of the semiconductor light emitting device according to the present invention is to form a light emitting film in which a semiconductor thin film composed of a layered cladding layer and an active layer sandwiched between the cladding layers is monolayer or multilayer laminated in a film shape. The forbidden band width of the cladding layer is greater than or equal to the forbidden band width of the active layer. In a second embodiment, the active layer is a superlattice structure, a quantum well structure, or a quantum wire structure. And a quantum box structure, wherein the active layer is a type 2 superlattice structure comprising a first semiconductor layer and a second semiconductor layer. The fourth aspect is characterized in that a third semiconductor layer is provided between the first semiconductor layer and the second semiconductor layer. And
A fifth aspect is characterized in that the active layer comprises a plurality of active layers having different emission wavelengths.

In a sixth aspect, a cladding layer is provided between a plurality of active layers having different emission wavelengths. In a seventh aspect, a side surface of the active layer is provided. The semiconductor layer is covered with a protective film having a forbidden band width larger than that of the active layer. In the eighth aspect, the semiconductor flake is formed by nitriding, phosphating, arsenic, oxidizing, selenium or the like. Or any of tellurium treatment, a protective film is formed on the side surface of the active layer,
In a ninth aspect, one of the cladding layers is n-type,
The other is p-type, and the semiconductor flake has pn
It is characterized in that a bond is formed.

A tenth aspect is characterized in that the material of the cladding layer is different across the active layer, and an eleventh aspect is that the semiconductor flake is provided on one of the cladding layers. a first semiconductor flake having a p-type region formed thereon;
A second semiconductor flake in which an n-type region is formed in one clad layer of the semiconductor flake; and a pn junction is formed by the first semiconductor flake and the second semiconductor flake. The twelfth aspect is characterized in that
The semiconductor flake is sandwiched between a p-type semiconductor layer and an n-type semiconductor layer, and a thirteenth aspect is that the cladding layer of the semiconductor flake is of a first conductivity type, The active layer is of a second conductivity type different from the cladding layer.

A fourteenth aspect is characterized in that the semiconductor flake is irradiated with an electron beam or light to emit light, and a fifteenth aspect is that the active layer comprises a superlattice,
A voltage is applied to the active layer, and the semiconductor flake is irradiated with an electron beam or light to emit light,
In a sixteenth aspect, the semiconductor flake is disposed between a first transparent electrode and a second transparent electrode, and a voltage applied between the first transparent electrode and the second transparent electrode is reduced. It is characterized by varying the light emission time by varying,
In a seventeenth aspect, light is emitted by applying a voltage to the semiconductor flake via an insulating layer. In an eighteenth aspect, the semiconductor flake is disposed between electrodes. In addition, light is emitted by injecting a current into the active layer of the semiconductor flake.

In a nineteenth aspect, the active layer or the cladding layer of the semiconductor flake is made of GaP, GaAs, InP, InP.
Characterized by being composed of a Group 2-6 compound semiconductor mixed crystal lattice-matched to any of As.
A twentieth aspect is characterized in that the active layer or the clad layer of the semiconductor flake is made of a Group 3-5 compound semiconductor mixed crystal lattice-matched to GaAs,
In a twenty-first aspect, the active layer or the cladding layer of the semiconductor flake is a crystal or amorphous such as an AlGaInP mixed crystal, an AlGaInN mixed crystal, or a 2-6 mixed crystal. In a twenty-second embodiment, the semiconductor flake has a thickness of 3 nm to 100 μm and a length of 3 nm to 1 μm.
mm in size.

In a first aspect of the method of manufacturing a semiconductor light emitting device according to the present invention, a semiconductor separation layer made of a first semiconductor material is formed on a substrate for crystal growth, and the first separation layer is formed on the semiconductor separation layer. A first step of alternately growing a first clad layer made of a semiconductor material different from the semiconductor material and a semiconductor thin layer made of an active layer and a second clad layer; and removing the semiconductor separation layer by selective etching. A second step, a third step of converting the semiconductor thin layer into a semiconductor thin layer, and a fourth step of forming and fixing the semiconductor thin film in a film shape on a substrate for forming a light emitting body In a second embodiment, following the fourth step, a fifth step of forming a pn junction by diffusing impurities into the semiconductor flake is performed.
In a third aspect, the surface of the substrate for crystal growth is partially covered with a non-semiconductor film, and the semiconductor separation layer is provided on an exposed portion of the substrate. The semiconductor flake layers are grown alternately by crystal, and a fourth aspect is that the semiconductor flakes include a first semiconductor flake having a p-type region formed in one clad layer; The semiconductor flake comprises a second semiconductor flake in which an n-type region is formed in one clad layer of the semiconductor flake. In a fifth aspect, the semiconductor flake comprises a p-type semiconductor layer and an n-type semiconductor flake. Characterized by being sandwiched between a mold semiconductor layer.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A semiconductor light emitting device according to the present invention forms a light emitting film in which a semiconductor thin film composed of a layered cladding layer and an active layer sandwiched between the cladding layers is monolayer or multilayer laminated. In addition, the forbidden band width of the cladding layer is not less than the forbidden band width of the active layer, and the active layer is a super lattice structure, a quantum well structure,
A quantum wire structure or a quantum box structure, and that a side surface of the active layer is covered with a protective film having a larger forbidden band width than the active layer. Because of the feature, the carrier is effectively confined, the luminous efficiency is high, the reproducibility is excellent, and the durability is high.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific examples of a semiconductor light emitting device and a method of manufacturing the same according to the present invention will be described in detail with reference to the drawings. (Specific Example 1) FIGS. 1 and 2 are views showing the structure of a specific example of a semiconductor light emitting device according to the present invention. FIG. 1 is a schematic diagram of a semiconductor light emitting device of a first specific example, and FIG. It is sectional drawing of a semiconductor flake.

FIGS. 1 and 2 show a light emitting film 15 in which a semiconductor thin film 14 composed of a layered cladding layer 12 and an active layer 13 sandwiched between the cladding layers 12 is laminated in a single layer or a multilayer. A semiconductor light emitting device in which the forbidden band width of the cladding layer is equal to or larger than the forbidden band width of the active layer is shown. This example will be described in further detail. On a substrate 11 made of glass, a clad layer 12 having a layer shape and an active layer 13 sandwiched between the clad layers 12 are, for example, 100 μm or less in thickness and 1 mm or less in size. The light emitting film 15 was formed by laminating the semiconductor thin pieces 14 in a film shape. The bandgap of the cladding layer 12 is larger than the bandgap of the active layer 13. Clad layer 1
2 and the active layer 13 are formed by vacuum evaporation, chemical vapor deposition (CV).
The crystal can be grown by a method D), a metal organic chemical vapor deposition (MOVPE) method, a molecular beam crystal growth (MBE) method, or the like. The light emitting film 15 can be formed by thinning this and applying it to the substrate. The cladding layer 12 and the active layer 13 are made of AlGa
It can be formed using crystals such as InP mixed crystal, AlGaInN mixed crystal, 2-6 mixed crystal, or amorphous.

When light having a wavelength larger than the band gap of the active layer 13 or an electron beam is applied in a vacuum, electrons and holes are formed in the active layer 13 and recombine to emit light. Since the bandgap of the cladding layer 12 is larger than the bandgap of the active layer 13, electrons and holes are confined in the active layer 13, and the luminous efficiency is high. Since the cladding layer 12 and the active layer 13 are layered, a heterointerface between the cladding layer 12 and the active layer 13 can be easily formed with good crystallinity. The emission wavelength is the active layer 1
Since it is determined by the forbidden band width of 3, a desired wavelength such as red, blue, or green can be obtained by selecting the material of the active layer 13. Most of the active layer 13 is
Since it is covered by the gas, it does not easily react with the atmospheric gas and is hardly deteriorated. The light emitting film 15 has a thickness of 100
Since the small semiconductor flakes 14 having a size of 1 μm or less and a size of 1 mm or less are laminated, they can be easily and uniformly formed on the substrate 11 having a large area.

Since this semiconductor light emitting device functions as a phosphor having a very high emission intensity, a fluorescent plate for an electron beam or light, a fluorescent lamp, a fluorescent display tube, a cathode ray tube display (CRT), a plasma display panel (PD)
P), electroluminescent display (EL)
D), it can be widely used for light emitting devices using fluorescent light such as light emitting diodes (LEDs) and display devices.

The active layer 13 in the semiconductor flake 14 is not limited to a single layer, but may be a plurality of layers as shown in FIG. By dividing the active layer 13 into layers that are thinner than the diffusion length of electrons and holes, the density of electrons and holes increases, and the luminous efficiency increases. In addition, since the thickness of the entire active layer 13 increases, the absorption coefficient for electron beams and light increases, and the emission intensity increases.

In this specific example, the light-emitting film is composed of only semiconductor flakes. However, the present invention is not limited to this, and semiconductor powder for filling gaps between semiconductor flakes, organic matter for fixing, and the like may be mixed. . In this specific example, the semiconductor thin piece has a flat plate shape. However, the present invention is not limited thereto, and the semiconductor thin piece may have a disk shape or an elliptical shape.

(Embodiment 2) FIG. 3A is a schematic view of a semiconductor thin film showing a second embodiment of the present invention, and FIG. 3B is a band lineup diagram. The semiconductor flake 14 includes a layered cladding layer 31 and an active layer 32, and the active layer 32 has a multiple quantum well structure in which quantum well layers 32a and quantum barrier layers 32b are alternately stacked. The forbidden bandwidth of the cladding layer 31 is larger than the forbidden bandwidth of the quantum well layer 32a. Quantum well layer 32a
Thickness is about the de Broglie wavelength of the carrier (about 10 nm)
And very thin. Cladding layer 31 and quantum well layer 32a
And the quantum barrier layer 32b can be grown by MOVPE or MBE. This can be sliced to form the semiconductor slice 14.

When light having a wavelength larger than the forbidden band width of the quantum well layer 32a or an electron beam is irradiated in a vacuum,
Electrons and holes are generated in the quantum well layer 32a, and recombine to emit light. The band lineup is as shown in FIG. 3B, and the valence band edge 33 is high and the conduction band edge 34 is low in the quantum well layer 32a. Due to the quantum effect, the state density of electrons and holes in the quantum well layer 32a becomes two-dimensional, so that the recombination probability increases and high luminous efficiency can be obtained. The cladding layer 31 has an effect of confining electrons and holes in the active layer 32 and protecting the active layer 32. Clad layer 3
1. Since the quantum well layer 32a and the quantum barrier layer 32b are layered, each hetero interface can be easily formed with good crystallinity. By selecting the quantum structure of the active layer 32, desired emission wavelengths such as red, blue, and green can be obtained. By forming the light emitting film by laminating the semiconductor flakes 14 in a film shape, it can be widely used as a fluorescent film in CRTs, PDPs and the like.

In this specific example, the multiple quantum well structure is used for the active layer. However, the present invention is not limited to this, and a single quantum well structure, a superlattice structure, a quantum wire structure, or a quantum well box structure may be used. (Specific Example 3) FIG. 4 (a) is a schematic view of a semiconductor flake showing a third specific example of the present invention, and FIG. 4 (b) is a band lineup diagram. The semiconductor flake 14 includes a cladding layer 41 and an active layer 42 made of a superlattice in which a first semiconductor layer 42a and a second semiconductor layer 42b are alternately stacked. Each of the first semiconductor layer 42a and the second semiconductor layer 42b has a thickness of about the de Broglie wavelength of carriers (about 10 nm) and is very thin. Cladding layer 41, first semiconductor layer 42a and second semiconductor layer 4
2b can be grown by MOVPE or MBE. This can be sliced to form the semiconductor slice 14.

The band lineup is as shown in FIG. 4B, in which both the valence band edge 33 and the conduction band edge 34 are low in the first semiconductor layer 42a and high in the second semiconductor layer 42b. 2 superlattices are formed. The electrons and holes generated by the irradiation of the electron beam or light are
However, electrons accumulate in the first semiconductor layer 42a, and holes accumulate in the second semiconductor layer 42b. Since electrons and holes are spatially separated, radiative recombination proceeds slowly, and the luminescence time (afterglow) increases. The length of the afterglow can be controlled by changing the superlattice structure and changing the degree of overlap between the electron and hole wave functions.

FIG. 5A is a schematic diagram of a semiconductor thin film using a superlattice suitable for controlling the length of afterglow.
(B) and FIG. 5 (c) are band lineup diagrams. The third semiconductor layer 51 is inserted between the first semiconductor layer 42a and the second semiconductor layer 42b. As shown in FIG. 5B, when the valence band edge 33 of the third semiconductor layer 51 is low and the conduction band edge 34 is high, electrons and holes are spatially separated, and the overlap of the wave functions becomes small. The afterglow is longer. As shown in FIG. 5C, when the valence band edge 33 of the third semiconductor layer 51 is high and the conduction band edge 34 is low, electrons and holes are spatially close to each other, and the overlap of the wave derivatives is reduced. Larger, shorter afterglow.

By using the type 2 superlattice to form a light emitting film by laminating the semiconductor flakes 14 having a long afterglow in a film shape and using the light emitting film for a CRT or PDP, a display that does not cause eyestrain is provided. A device is obtained. Further, those having a very long afterglow can be used for a night sign, a luminous clock, and the like. In this embodiment, a type 2 superlattice in which semiconductors of different materials are stacked in the active layer is used. However, the present invention is not limited to this, and a nipi superlattice in which a p-layer and an n-layer are stacked may be used. In the nipi superlattice, since electrons are accumulated in the n-type semiconductor layer and holes are accumulated in the p-type semiconductor layer, electrons and holes are spatially separated, and the same effect is obtained.

(Embodiment 4) FIGS. 6A and 6B are schematic views of a semiconductor flake showing a fourth embodiment of the present invention.
The semiconductor flake 14 includes a layered cladding layer 61, a first active layer 62 a emitting red light, and a second active layer 6 emitting green light.
2b and an active layer 62 composed of a third active layer 62c that emits blue light. In order to control the emission wavelengths of the first active layer 62a, the second active layer 62b, and the third active layer 62c, materials having different forbidden bandwidths may be used or impurities to be added may be changed. In the structure of FIG. 6A, the first active layer 6
2a, the second active layer 62b, and the third active layer 62c are adjacent to each other. Since the forbidden band width of the first active layer 62a is narrowest, light emission in the first active layer 62a easily occurs. First active layer 6
By controlling the layer thickness of 2a, the second active layer 62b, and the third active layer 62c, an arbitrary light emission such as white light can be obtained.
In the structure of FIG. 6B, the first active layer 62a and the second
The active layer 62b and the third active layer 62c are separated by the cladding layer 61. In this structure, the interference between the active layers 62 is small, and the adjustment of the emission intensity from each layer is easy,
Arbitrary light emission including white can be easily obtained.

By forming the light emitting film by laminating the semiconductor flakes 14 into a film shape, a CRT or PD is used as a fluorescent film.
It can be widely used for P, ELD, fluorescent display tubes and the like. In this specific example, an active layer having a bulk characteristic was used.
The structure using the quantum effect, such as a quantum well structure, a superlattice structure, a quantum wire structure, and a quantum well box structure, may be used. Further, a type 2 superlattice may be used.

(Embodiment 5) FIG. 7 is a sectional view of a semiconductor flake showing a fifth embodiment of the present invention. The semiconductor flake 14 is
An active layer 72 having a layered cladding layer 71 and an active layer 72;
Are covered with a protective film 73. The protective film 73 can be formed by spraying a material for the protective film on the semiconductor flake 14, or by growing a crystal at the same time when the cladding layer 71 is grown.

When the light emitting film is formed by laminating the semiconductor thin pieces 14, the side surface of the active layer 72 is covered with the protective film 7 having a large forbidden band width.
3, the luminous efficiency is high and the element life is prolonged. As a result, a CRT with a high luminance and a P
DP is obtained. In this specific example, an active layer having a bulk characteristic is used, but the present invention is not limited to this, and a structure using a quantum effect such as a quantum well structure, a superlattice structure, a quantum wire structure, or a quantum well box structure may be used. Further, a type 2 superlattice may be used.

(Embodiment 6) FIG. 8 is a sectional view of a semiconductor flake showing a sixth embodiment of the present invention. The semiconductor flake 14 is
It comprises a layered cladding layer 81 and an active layer 82 and is made of a Group 3-5 compound semiconductor. The surface of the semiconductor flake 14 is nitrided, and the nitride layer 83 and the active layer 8
The protective film 84 is provided on two side surfaces. Nitride layer 83 and protective film 84
Can be formed by heating the semiconductor flake 14 in a nitrogen atmosphere.

When the side surface of the active layer 82 is exposed, electrons and holes may recombine non-radiatively due to surface recombination. In particular, in a group 3-5 compound semiconductor, it is known that an oxide on a crystal surface becomes a non-radiative recombination center. As a method for avoiding this, the surface may be covered with a material having a large forbidden band width, or may be protected with a material that does not become a non-radiative recombination center. When the active layer 82 made of a Group 3-5 compound semiconductor is nitrided, the band gap of the protective film 84 is increased and oxygen on the surface is reduced, so that surface recombination is reduced and luminous efficiency is increased. The service life is also prolonged. By forming the light emitting film by laminating the semiconductor thin pieces 14 in a film shape, a CRT, an ELD, a PD having a high light emitting efficiency can be obtained.
P and the like are obtained.

In this specific example, a group 3-5 compound semiconductor is used for the active layer and a nitride is used for the protective film. However, the present invention is not limited to this, and phosphide or arsenide is formed on the surface of the group 3-5 compound semiconductor. May be. Further, an oxide, a sulfide, a selenide, or a telluride may be formed on the surface of the Group 2-6 compound semiconductor. Since the elements of nitrogen, phosphorus, arsenic, oxygen, sulfur, selenium, and tellurium have high vapor pressures, these compounds can be easily formed on the side surface of the active layer simply by placing a semiconductor flake in these atmospheres.

(Embodiment 7) FIG. 9 is a schematic view of a semiconductor light emitting device showing a seventh embodiment of the present invention. A transparent electrode 91, a light emitting film 95, and an insulator film 9 are formed on a substrate 90 made of glass.
6. The metal electrodes 97 are stacked. The light emitting film 95 is formed by laminating semiconductor thin pieces 94 having a thickness of 100 μm or less and a size of 1 mm or less in a film shape. Semiconductor flake 94
Are a layered p-type cladding layer 92a and an n-type cladding layer 92a.
b and the active layer 93 sandwiched between them. When the lamination direction of the semiconductor flakes 94 is not constant, about 50% of the semiconductor flakes 94 have the p-type cladding layer 92a on the upper side, and
For the remaining 50%, the n-type cladding layer 92b is on the upper side. p
The type cladding layer 92a, the n-type cladding layer 92b, and the active layer 93 can be grown by MOVPE or MBE.

The active layer 93 emits light by applying a DC or AC voltage to the transparent electrode 91 and the metal electrode 97. Since the semiconductor thin film 94 has the p-type cladding layer 92a and the n-type cladding layer 92b, the semiconductor flake 94 becomes a pn junction in a forward direction with respect to an applied electric field.
A current flows toward the mold cladding layer 92b, and light emission with high luminance is obtained. Since the p-type cladding layer 92a and the n-type cladding layer 92b have conductivity, light is emitted at a low applied voltage. Light passes through the transparent electrode 91 and the substrate 90 and is extracted to the outside. By forming the transparent electrode 91 and the metal electrode 97 in a stripe shape crossing each other, a flat display can be obtained. By reflecting light by the insulator film 96 and the metal electrode 97, light emission intensity can be increased.

In this specific example, the insulator film is used, but the insulator film may not be used. Although the lamination direction of the semiconductor flakes is not controlled, the lamination direction of all the semiconductor flakes may be aligned and the direction of the pn junction may be the same. Further, in this specific example, a single active layer was used, but the present invention is not limited to this.
A structure such as a superlattice structure, a quantum well, a quantum wire, or a quantum box may be used.

In this specific example, no treatment was applied to the end face of the semiconductor flake, but any one of nitridation, phosphidation, arsenification, oxidation, sulfidation, selenization, and tellurization was applied to the protective film. May be formed. Further, the light-emitting film is composed of only the semiconductor flakes. However, the present invention is not limited thereto, and a semiconductor powder for filling a gap between the semiconductor flakes, an organic substance for fixing, and the like may be mixed.

(Embodiment 8) FIG. 10A shows an eighth embodiment of the present invention.
FIG. 10B is a schematic diagram of a semiconductor thin section showing a specific example of FIG. The semiconductor flake 14 includes a layered n-type cladding layer 101a, an active layer 102, and a p-type cladding layer 101b.
The band gap of the mold cladding layer 101b is larger than that of the active layer 102. The n-type cladding layer 101a is made of a semiconductor material that can be easily doped with n-type, and the p-type cladding layer 101b is made of a semiconductor material that can be easily doped with p-type. Generally, in a semiconductor material having a large forbidden band, either n-type or p-type conductivity is easily obtained. For example, ZnSe is easily an n-type, and ZnTe is easily a p-type. It is considered that such characteristics are caused by the positions of the valence band edge 33 and the conduction band edge 34. As shown in FIG. 10B, a semiconductor having a low conduction band edge 34 is used for the n-type cladding layer 101a, and a valence band edge 33 is formed for the p-type cladding layer 101b.
Use of a semiconductor having a high resistance allows easy doping of both the n-type and the p-type, and a low resistance pn
A bond is obtained. By laminating the semiconductor flakes 14 in the form of a film to form a light emitting film and injecting a current, an ELD with high luminous efficiency can be obtained.

In this embodiment, a single active layer is used. However, the present invention is not limited to this. A superlattice structure, a quantum well, a quantum wire,
A structure such as a quantum box may be used. (Embodiment 9) FIG. 11 is a schematic view of a semiconductor light emitting device showing a seventh embodiment of the present invention. FIG. 11 shows a first semiconductor flake in which a p-type region 112a is formed in one clad layer of a semiconductor flake 114, and a second semiconductor in which an n-type region 112b is formed in one clad layer of the semiconductor flake 114 A semiconductor light emitting device including a thin section is shown.

This example will be described in more detail. A transparent electrode 111 and a light emitting film 1 are formed on a substrate 110 made of glass.
15, metal electrodes 116 are stacked. Light emitting film 115
Is a film obtained by laminating semiconductor flakes 114 in a film shape. A region in contact with the transparent electrode 111 is a p-type layer 115a, and a region in contact with the metal electrode 116 is an n-type layer 115b.
It has an -n junction. The semiconductor flake 114 includes a layered cladding layer 112 and an active layer 113. Transparent electrode 1
The cladding layer 112 in a region in contact with 11 is doped with p-type to form a p-type region 112a. The cladding layer 112 in a region that is in contact with the metal electrode 116 is doped with n-type to form an n-type region 112b. The combination of the individual p-type regions 112a forms a p-type layer 115a.
The combination of the individual n-type regions 112b is an n-type layer 115b.

The p-type layer 115a has a p-type layer
After forming the layer impurities, the semiconductor flakes 114 are stacked, and the p-type impurities are diffused into the cladding layer 112 of the semiconductor flakes 114. Also,
The n-type layer 115b can be formed by, for example, laminating the semiconductor flakes 114 in layers and then diffusing n-type impurities.

The active layer 113 emits light by applying a positive voltage to the transparent electrode 111 and a negative voltage to the metal electrode 116.
Light passes through the transparent electrode 111 and the substrate 110 and is extracted to the outside. The active layer 113 has a pn junction composed of a p-type layer 115a and an n-type layer 115b.
Holes are injected from 5a and electrons are injected from n-type layer 115b. Since the rising voltage of the pn junction is several volts, light emission can be obtained at a low voltage. Further, since the pn junction has an effect of confining holes and electrons in the active layer 113,
Luminous efficiency is also high. By forming the transparent electrode 111 and the metal electrode 116 in a stripe shape crossing each other, a flat display having a low LED-like operating voltage can be obtained. Further, by setting the emission wavelength of the active layer 113 to three colors of red, green, and blue, a color display can be obtained.

In this specific example, a single active layer is used. However, the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was performed on the end face of the semiconductor flake, but nitriding, phosphating,
The protective film may be formed by performing any of arsenic, oxidation, sulfurization, selenization, and tellurization. In addition, the light-emitting film was composed of only semiconductor flakes, but is not limited to this.
A semiconductor powder for filling a gap between semiconductor flakes, an organic substance for fixing, or the like may be mixed.

(Embodiment 10) FIG. 12 is a schematic view of a semiconductor light emitting device showing a tenth embodiment of the present invention. A transparent electrode 121, an n-type semiconductor layer 122, a light emitting film 126, a p-type semiconductor layer 127, and a metal electrode 128 are stacked on a substrate 120 made of glass. The light-emitting film 126 is formed by laminating semiconductor flakes 125 in a film shape.
22 and the p-type semiconductor layer 127. The semiconductor flake 125 has a structure in which an active layer 124 is sandwiched between cladding layers 123, and the active layer 124 is located between the n-type semiconductor layer 122 and the p-type semiconductor layer 127. n-type semiconductor layer 12
2 and the p-type semiconductor layer 127 can be formed by forming an amorphous semiconductor layer or the like to which an impurity is added by a vapor phase growth method or the like.

When a negative voltage is applied to the transparent electrode 121 and a positive voltage is applied to the metal electrode 128, the active layer 124 emits light, and n
The light passes through the mold semiconductor layer 122, the transparent electrode 121, and the substrate 120 and is extracted to the outside. Since the n-type semiconductor layer 122 and the p-type semiconductor layer 127 are layered, the operating voltage becomes more uniform, and stable light emission characteristics can be obtained over a wide area.
By forming the transparent electrode 121 and the metal electrode 128 in a stripe shape crossing each other, a flat display having a low LED-like operating voltage can be obtained. Further, by setting the emission wavelength of the active layer 124 to three colors of red, green, and blue, a color display can be obtained.

In this example, a single active layer is used. However, the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was performed on the end face of the semiconductor flake, but nitriding, phosphating,
The protective film may be formed by performing any of arsenic, oxidation, sulfurization, selenization, and tellurization. In addition, the light-emitting film was composed of only semiconductor flakes, but is not limited to this.
A semiconductor powder for filling a gap between semiconductor flakes, an organic substance for fixing, or the like may be mixed.

(Embodiment 11) FIG. 13 shows an eleventh embodiment of the present invention.
It is the schematic of the semiconductor light emitting device which shows the specific example of. FIG.
The cladding layer 132 of the semiconductor flake 134
Wherein the active layer 133 is of a conduction type p-type (n-type) different from the cladding type.

This specific example will be described in more detail. A transparent electrode 131 and a light emitting film 1 are formed on a substrate 130 made of glass.
35, and a metal electrode 136 are stacked. Light-emitting film 135
Is obtained by laminating semiconductor flakes 134 in a film shape. The semiconductor flakes 134 have a structure in which a p-type active layer 133 is sandwiched between an n-type cladding layer 132.

The light emitting film 135 emits light by applying a DC or AC voltage to the transparent electrode 131 and the metal electrode 136. At the interface between the cladding layer 132 and the active layer 133, p
A -np junction is formed, and when a voltage is applied from the outside, electrons and holes are intensively applied to the pnp junction to generate electrons and holes. Since the cladding layer 132 and the active layer 133 are doped, the voltage required for light emission is lower and the power consumption is lower than in a conventional EL device. By controlling the emission wavelength of the active layer 133, an arbitrary emission color such as white can be obtained, which can be used for an ELD, a white light source, and the like.

In this specific example, the cladding layer is n-type and the active layer is p-type. However, the cladding layer may be p-type and the active layer may be n-type. In this specific example, a single active layer is used, but the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was performed on the end face of the semiconductor flake, but nitriding, phosphating,
The protective film may be formed by performing any of arsenic, oxidation, sulfurization, selenization, and tellurization. In addition, the light-emitting film was composed of only semiconductor flakes, but is not limited to this.
A semiconductor powder for filling a gap between semiconductor flakes, an organic substance for fixing, or the like may be mixed.

(Embodiment 12) FIG. 14 is a schematic view of a semiconductor light emitting device showing a twelfth embodiment of the present invention. A transparent electrode 141 and a light emitting film 144 are formed on a substrate 140 made of glass.
And a cold cathode 145 and a gate 14 via a vacuum space.
6, an insulator 147, a cathode 148, and a substrate 149.
The light emitting film 144 includes the semiconductor flake 142 and the semiconductor particles 143.
Are laminated in the form of a film.
Reference numeral 2 denotes a layered active layer 142a and a cladding layer 142b. The cold cathode 145 is a metal cone having a diameter of about 1 μm. By applying a voltage for extracting electrons between the cathode 148 and the gate 146 and applying an electric field for acceleration between the transparent electrode 141 and the cathode 148, electrons are extracted from the cold cathode 145 constituting the electron gun, and the light emitting film 144 is emitted. To reach. The semiconductor flake 1 in the light emitting film 144 is generated by this electron beam.
Electrons and holes are generated at 42 and recombine in the active layer 142a to emit light. Light passes through the transparent electrode 141 and the substrate 140 and is extracted to the outside. By changing the forbidden band width of the material of the active layer 142a, light of an arbitrary wavelength such as red, blue, green, and white can be obtained. In addition, the semiconductor flakes 142 that emit red, blue, and green light are distributed in a matrix, and a specific cold cathode 1 is formed.
By extracting electrons from 45, a two-dimensional color screen is obtained. The semiconductor particles 143 increase the mechanical strength of the light emitting film 144 and prevent the semiconductor flakes 142 from being deteriorated by electrons. Active layer 142a is clad layer 142b
, A display with high luminance can be obtained. In addition, deterioration due to electron beam irradiation hardly occurs, and the life of the device is long.

In this specific example, the light was emitted by irradiating the light emitting film with electrons from the field emission type cold cathode. However, the present invention is not limited to this. The light-emitting film may emit light by irradiation with light emitted from a light-emitting diode or a semiconductor laser that has been irradiated with ultraviolet light. By arranging excitation sources such as plasma discharges, light emitting diodes, and semiconductor lasers in a two-dimensional matrix, a display with extremely high luminance and a small thickness can be obtained.

In this specific example, a single active layer is used. However, the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was performed on the end face of the semiconductor flake, but nitriding, phosphating,
The protective film may be formed by performing any of arsenic, oxidation, sulfurization, selenization, and tellurization. Further, although the light emitting film is composed of the semiconductor flakes and the semiconductor particles, the present invention is not limited to this, and an organic substance for fixing the semiconductor flakes and the semiconductor particles may be mixed.

(Example 13) FIG. 15A is a schematic view of a semiconductor light emitting device showing a thirteenth example of the present invention.
FIG. 15B is a schematic view of a semiconductor slice, and FIG. 15C is a band profile. A first transparent electrode 151, a light emitting film 155, and a second transparent electrode 15 are formed on a substrate 150 made of glass.
6. It has a light emitting diode (LED) 157 and an electrode 158. The light-emitting film 155 is excited by the LED 157, and the light-emitting film 1 is excited.
The light emitting time of the light emitting film 155 can be controlled by a voltage applied to the light emitting film 55. The light emitting film 155 is formed by laminating semiconductor flakes 154 in a film shape.
Is composed of a layered cladding layer 152 and an active layer 153. The active layer 153 includes, as shown in FIG.
It is composed of a superlattice in which first semiconductor layers 153a and second semiconductor layers 153b are alternately stacked. When electricity is supplied between the second transparent electrode 156 and the electrode 158, the LED 157 emits light. LE
By making the emission wavelength of D157 shorter than the emission wavelength of active layer 153, light emission from LED 157 is absorbed by light emitting film 155, and fluorescence is obtained from light emitting film 155.
The fluorescence from the light emitting film 155 is applied to the first transparent electrode 151 and the substrate 1
It passes through 50 and is taken out. First transparent electrode 1
FIG. 15 shows a band profile of the semiconductor flake 154 when a voltage is applied between the first transparent electrode 51 and the second transparent electrode 156.
It is shown in (c). First semiconductor layer 153a and second semiconductor layer 1
An example in which 53b is a type 2 superlattice will be described.
When the applied voltage is zero, electrons move to the first semiconductor layer 153a,
The holes exist in the second semiconductor layer 153b, and the light emission time is extremely long. When a voltage is applied, electrons and holes move toward one side of the first semiconductor layer 153a and the second semiconductor layer 153b, respectively, and the overlap of the wave functions increases, and as a result, the light emission time is shortened. That is, the first transparent electrode 15
By changing the voltage between the first and second transparent electrodes 156, the light emitting time of the light emitting film 155 can be changed. Vp in FIG. 15 is the variable power supply. Further, by forming the first transparent electrode 151 and the electrode 158 in a stripe structure in a direction perpendicular to the second transparent electrode 156, it is possible to arbitrarily set the light emission time of only a specific area of the two-dimensional display. Such characteristics are useful for a display for measurement and the like.

In this example, the active layer 153 has a type 2
Is used, but the present invention is not limited to this, and a type 1 superlattice may be used. In the case of the type 1 superlattice, the emission time becomes longer as the voltage is applied. In this specific example, the light from the light emitting diode was irradiated to the light emitting film to emit light, but the invention is not limited to this, and the light is emitted by irradiating electrons or emitting ultraviolet light generated by plasma discharge. Or
The light-emitting film may emit light by irradiating light or the like generated from a semiconductor laser.

In this specific example, no treatment was applied to the end face of the semiconductor flake, but any one of nitriding, phosphating, arsenicating, oxidizing, sulfurizing, selenizing, and tellurizing was performed to form a protective film. May be. Further, although the light emitting film is composed of semiconductor flakes, the present invention is not limited to this, and an organic substance or the like for fixing the semiconductor flakes may be mixed. (Example 14) FIG. 16 is a schematic view of a semiconductor light emitting device showing a fourteenth example of the present invention. Substrate 1 made of glass
A transparent electrode 161 having a stripe shape, a first insulating layer 162, a light-emitting film 167, a second insulator layer 168, and a back electrode 169 having a stripe shape are laminated on 60. Light-emitting film 167
Is a film-like laminate of a mixture of semiconductor flakes 163 and semiconductor particles 166. The semiconductor flake 163 is
It comprises a cladding layer 164 and an active layer 165. The direction of the stripe of the transparent electrode 161 and the back electrode 169 is 90 degrees.
Crosses at degrees.

When a DC or AC voltage is applied between any of the stripes of the transparent electrode 161 and any of the stripes of the back electrode 169, the light emitting film 167 at the intersection of the stripes of the transparent electrode 161 and the back electrode 169 is applied. Emits light. Light passes through the transparent electrode 161 and the substrate 160 and is extracted to the outside. Transparent electrode 161 and back electrode 169
By selecting the stripes, a two-dimensional image can be obtained.

The presence of the first insulating layer 162 and the second insulating layer 168 makes it difficult for dielectric breakdown near the transparent electrode 161 and the back electrode 169 to occur. Further, since the active layer 165 is sandwiched between the cladding layers 164, the luminous efficiency is high and the deterioration is slow. The semiconductor particles 166 increase the mechanical strength of the light emitting film 167 and prevent the semiconductor flake 163 from deteriorating. Since the emission wavelength can be easily changed only by changing the material of the active layer 165, a color image such as red, blue, and green can be easily obtained.

In this specific example, two insulator layers are used, but only one insulator layer may be used. Although a single-layer semiconductor is used for the active layer, the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was applied to the end face of the semiconductor flake, but even if a protective film was formed by performing any of nitriding, phosphating, arsenic, oxidizing, sulfide, selenizing, and tellurizing treatments Good. Further, although the light emitting film is composed of the semiconductor flakes and the semiconductor particles, the present invention is not limited to this, and an organic substance for fixing the semiconductor flakes and the semiconductor particles may be mixed.

(Embodiment 15) FIG. 17 is a schematic view of a semiconductor light emitting device showing a fifteenth embodiment of the present invention. A transparent electrode 17 having a stripe shape is formed on a substrate 170 made of glass.
1, a light emitting film 172, and a striped back electrode 177 are stacked. The light-emitting film 172 is obtained by mixing a semiconductor thin piece 173 with a binder 176 and applying it in a film shape. The semiconductor flake 173 has a structure in which an active layer 175 is sandwiched between cladding layers 174. Transparent electrode 171 and back electrode 177
The directions of the stripes intersect at an angle of 90 degrees.

When a DC or AC voltage is applied between any of the stripes of the transparent electrode 171 and any of the stripes of the back electrode 177, the light emitting film 172 at the intersection of the stripes of the transparent electrode 171 and the back electrode 177 is applied. Emits light. Light passes through the transparent electrode 171 and the substrate 170 and is extracted to the outside. Transparent electrode 171 and back electrode 177
By selecting the stripes, a two-dimensional image can be obtained.

Since the structure has no insulating layer, the operating voltage is reduced. Since the active layer 175 is sandwiched between the cladding layers 174, dielectric breakdown hardly occurs. When the cladding layer 174 has p-type or n-type conductivity, the voltage applied to the cladding layer 174 is reduced, so that dielectric breakdown is further less likely to occur. The binder 176 is the light emitting film 17
2 to increase the mechanical strength and prevent the semiconductor thin section 173 from deteriorating.

In this example, a single active layer is used. However, the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. The emission wavelength of the active layer is red,
By using blue and green, a full-color display can be obtained.
Also, a white light source can be obtained. In this specific example, no treatment was applied to the end face of the semiconductor flake, but even if a protective film was formed by performing any of nitriding, phosphating, arsenic, oxidizing, sulfide, selenizing, and tellurizing treatments Good.

(Specific Example 16) The first embodiment of the present invention will be described with reference to FIG.
Example 6 will be described. BeMgSSe mixed crystal, BeMgZnS mixed crystal or BeZnS lattice-matched to GaP is formed on the cladding layer 12 and the active layer 13 constituting the semiconductor thin piece 14.
Ultraviolet light emission can be obtained by using a Se mixed crystal or a BeZnSeTe mixed crystal. Ag, Au,
Cu, Mn, Sn, Tb, Cl, Al, Ga, In,
By adding one or more impurities such as N, P, As, and Sb, blue or green light emission can be obtained.

The cladding layer 12 and the active layer 13 have Ga
MgZnSSe mixed crystal or BeMgZn lattice-matched to As
By using Se mixed crystal, ZnCdSSe mixed crystal, BeZnCdSe mixed crystal, etc., light emission in the blue to ultraviolet region can be obtained. Ag, Au, Cu, Mn, Sn, T
By adding one or more impurities such as b, Cl, Al, Ga, In, N, P, As, and Sb, blue or green light emission can be obtained.

In the cladding layer 12 and the active layer 13, In
MgZnCdSe mixed crystal or MgZnSe lattice-matched to P
By using a Te mixed crystal, a ZnCdSSe mixed crystal, or the like, light emission in a range from red to ultraviolet can be obtained. Ag, Au, Cu, Mn, Sn, Tb, Cl, Al, G
The emission wavelength can also be controlled by adding one or more impurities such as a, In, N, P, As, and Sb.

In the cladding layer 12 and the active layer 13, In
MgZnSeTe mixed crystal or MgZnS lattice-matched to As
By using an eTe mixed crystal, a ZnMnSeTe mixed crystal, or the like, red to blue light emission can be obtained. Ag on the active layer 13
And Au, Cu, Sn, Tb, Cl, Al, Ga, In,
The emission wavelength can also be controlled by adding one or more impurities such as N, P, As, and Sb.

In the above-described structure, since the lattice matching is performed with the substrate, a light emitting device having very few crystal defects and extremely high luminous efficiency can be obtained. In this specific example, a single active layer is used, but the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was applied to the end face of the semiconductor thin piece. However, any one of oxidation, sulfidation, selenization, and tellurium treatment may be applied to form the protective film.

(Specific Example 17) Referring to FIG.
7 will be described. An AlGaInP mixed crystal, an AlInAsP mixed crystal, or a GaIn
By using an AsP mixed crystal or the like, red to yellow light emission can be obtained. Be, Mg, Zn, Cd, O,
By adding one or more impurities such as S, Se, Te, C, Si, and Ge, red to yellow light emission can be obtained.

In the above-described structure, since the lattice matching is performed with the substrate, a light emitting device having very few crystal defects and extremely high luminous efficiency can be obtained. In this specific example, a single active layer is used, but the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was performed on the end face of the semiconductor thin piece. However, any one of nitriding, phosphating, and arsenic may be performed to form the protective film.

(Embodiment 18) The first embodiment of the present invention will be described with reference to FIG.
8 will be described. By using an AlGaInN mixed crystal for the cladding layer 12 and a GaInN mixed crystal for the active layer 13 constituting the semiconductor flake 14, red to ultraviolet light can be obtained. Mg, Be, Zn, Cd, O,
The emission wavelength can also be controlled by adding one or more impurities such as S, Se, and Te.
In this material system, a crystal having high luminous efficiency can be obtained even if the cladding layer 12 and the active layer 13 are not lattice-matched.

In this specific example, a single active layer is used. However, the present invention is not limited to this, and a structure such as a superlattice, a quantum well, a quantum wire, or a quantum box may be used. In this specific example, no treatment was performed on the end surfaces of the semiconductor thin pieces. However, a protective film may be formed by performing a nitriding treatment. (Embodiment 19) FIG. 18 is a process chart showing a nineteenth embodiment of the present invention. First, as shown in FIG. 18A, a semiconductor separation layer 181, a cladding layer 182,
The active layer 183 is crystal-grown. A material capable of epitaxial growth is used for the substrate 180, and the crystal is grown by MOVPE.
It can be performed by a method or MBE method. Next, FIG.
As shown in (b), the semiconductor separation layer 181 is immersed in a solution (or gas) for selectively etching, the semiconductor separation layer 181 is removed, and the semiconductor film 184 including the cladding layer 182 and the active layer 183 is removed from the substrate 180. To separate. Substrate 1
In order for the semiconductor isolation layer 181 to be easily removed over the entire surface 80, the semiconductor isolation layer 181 must be made of a material that is very easily etched. Such materials include AlAs, AlP, AlSb, and AlN, which are highly corrosive.
Al compound such as MgS, MgSe, MgTe such as MgTe, CaS such as CaSe, CaTe
Compounds. Because these materials are highly reactive,
Etching can be easily performed with a strong acid, hydrogen peroxide, halogen gas, or the like. For the cladding layer 182 and the active layer 183, a mixed crystal material having an Al composition ratio of 80% or less among Group III elements or a mixed crystal material having a Mg / Ca composition ratio of 80% or less among Group II elements is used. It may be used. The semiconductor film 184 separated from the substrate 180 is broken by a light mechanical push, resulting in a semiconductor flake 185 having a size of 1 mm or less as shown in FIG. Depending on the degree to which the semiconductor film 184 is pulverized, the size of the semiconductor thin piece 185 may be 1 micron to 1 micron.
mm. Next, as shown in FIG. 18D, the semiconductor flake 185 is mixed with a solvent 186 such as an organic solvent.
After that, it is applied on a non-semiconductor substrate 187 such as glass. The light emitting film 188 is formed by vaporizing the solvent 186. Using this process, a fluorescent screen, CRT, PDP, EL
D fluorescent lamps, fluorescent display tubes, light emitting elements using fluorescent light such as LEDs, and display devices can be manufactured.

The cladding layer 182 and the active layer 183 are
Since the crystal is grown on 80, a display device with few crystal defects and high luminous efficiency can be obtained. Further, the composition of the film thickness can be easily controlled, and the reproducibility is excellent. After crystal growth, a large number of semiconductor thin pieces 185 can be manufactured by one crystal growth because they are separated by the semiconductor separation layer 181. Substrate 180
The upper part can be reused, and the production cost is reduced. Since it is pulverized into semiconductor flakes 185 having a size of 1 mm or less, it can be applied to a non-semiconductor substrate 187 having a large area or a curved surface, and a display device such as a large display can be easily obtained.

As described above, the semiconductor flakes constituting the light emitting film include a semiconductor separation layer made of the first semiconductor material on the substrate for crystal growth, and a semiconductor different from the first semiconductor material on the semiconductor separation layer. A first step of alternately growing crystals of a first cladding layer made of a material, an active layer, and a semiconductor thin layer made of a second cladding layer; and a second step of removing the semiconductor separation layer by selective etching. A third step of converting the semiconductor thin layer into a semiconductor thin layer and a fourth step of forming and fixing the semiconductor thin film in a film shape on a substrate for forming a light emitting body. .

(Embodiment 20) FIG. 19 is a process chart showing a twentieth embodiment of the present invention. First, as shown in FIG. 19A, a non-semiconductor film 191 made of a dielectric or metal is formed on a substrate 190. The non-semiconductor film 191 has a round window. Next, as shown in FIG. 19B, the semiconductor separation layer 1 is formed on the surface of the substrate 190 without the non-semiconductor film 191.
92, the cladding layer 193, and the active layer 194 are selectively grown. A material capable of epitaxial growth is used for the substrate 190, and selective crystal growth can be performed by MOVPE, MBE, or the like. When the semiconductor separation layer 192 is removed by etching, a columnar semiconductor thin piece 195 is obtained as shown in FIG. Since the shape of the semiconductor thin piece 195 is determined by the shape of the window of the non-semiconductor film 191, the semiconductor thin piece 195 having a uniform shape can be easily formed. This is laminated on glass or the like to form a light emitting film, and a display device such as a large display is manufactured. Since the shapes of the semiconductor thin pieces 195 are uniform, variations in light emission characteristics are extremely small.

In this specific example, a columnar semiconductor flake is manufactured by making the shape of the window of the non-semiconductor film into a circle. However, the shape of the window of the non-semiconductor film may be a square or a stripe. . (Specific Example 21) FIG. 20 is a process chart showing a twenty-first specific example of the present invention. First, as shown in FIG. 20A, after forming a transparent electrode 201 on a substrate 200 made of glass or the like, an n-type impurity 202 for diffusion is deposited by vapor deposition or the like. Next, as shown in FIG. 20B, a light emitting film 206 is formed by laminating a semiconductor piece 205 made of a p-type semiconductor on the n-type impurity 202. Semiconductor flake 205
Is a laminate of a cladding layer 203 and an active layer 204, each of which is made of a p-type semiconductor. Further, a metal electrode 207 is laminated. Next, heat is applied to the n-type impurity 202.
Is diffused into the light emitting film 206. The n-type impurity 202 may be made of a material whose diffusion can be easily controlled. For example, when the light-emitting film 206 is a Group 2-6 semiconductor, In, Ga, Al
Etc. may be used. As a result of diffusing the n-type impurity 202, an n-type diffusion layer 203a is formed in a part of the cladding layer 203 as shown in FIG. Semiconductor slice 2
05 is p-type, the interface between the diffusion layer 203a and p-type
An n-junction is formed. Transparent electrode 201 and metal electrode 207
By applying a voltage between the active layer 204 and the active layer 204, light emission is obtained. Since a pn junction is formed by diffusion, a large-area process is possible, and it can be easily applied to a large-sized display or the like. Since a pn junction is used, low-voltage DC driving is possible.

In this specific example, the light emitting film is stacked after the n-type impurity is stacked. However, the present invention is not limited to this, and the n-type impurity may be stacked after the light emitting film is stacked. Also, the light-emitting film is p
Although a pn junction is formed by diffusing an n-type impurity as a type semiconductor, the present invention is not limited to this, and a pn junction may be formed by diffusing a p-type impurity with an n-type semiconductor as a light emitting film. Also,
The light emitting film may be undoped to diffuse a p-type impurity and an n-type impurity to form a pn junction.

[0075]

As described above, the light emitting device of the present invention has high luminance because it uses the active layer and the cladding layer having high crystallinity. In addition, since the semiconductor flakes are formed into a film shape, a display device that emits light uniformly over a wide area can be easily obtained. Further, since a conductive semiconductor is used, a light-emitting display device with low operating voltage can be obtained.

Further, according to the manufacturing method of the present invention, the semiconductor separation layer, the cladding layer and the active layer are alternately crystal-grown, separated into semiconductor flakes and formed into a film, so that mass production is easy and cost is reduced. Becomes lower.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a semiconductor light emitting device.

FIG. 2 is a schematic view of a semiconductor flake.

FIG. 3 is a schematic diagram of a semiconductor thin section and a band lineup diagram.

FIG. 4 is a schematic diagram of a semiconductor thin section and a band lineup diagram.

FIG. 5 is a schematic diagram of a semiconductor thin section and a band lineup diagram.

FIG. 6 is a schematic diagram of a semiconductor thin section and a band lineup diagram.

FIG. 7 is a sectional view of a semiconductor flake.

FIG. 8 is a cross-sectional view of a semiconductor flake.

FIG. 9 is a schematic view of a semiconductor light emitting device.

FIG. 10 is a schematic diagram of a semiconductor thin section and a band lineup diagram.

FIG. 11 is a schematic view of a semiconductor light emitting device.

FIG. 12 is a schematic view of a semiconductor light emitting device.

FIG. 13 is a schematic view of a semiconductor light emitting device.

FIG. 14 is a schematic view of a semiconductor light emitting device.

FIG. 15 is a schematic diagram and a band profile of a semiconductor light emitting device and a semiconductor thin section.

FIG. 16 is a schematic view of a semiconductor light emitting device.

FIG. 17 is a schematic view of a semiconductor light emitting device.

FIG. 18 is a process chart.

FIG. 19 is a process chart.

FIG. 20 is a process chart.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 On substrate 12 Cladding layer 13 Active layer 14 Semiconductor flake 15 Light emitting film 31 Cladding layer 32a Quantum well layer 32b Quantum barrier layer 32 Active layer 33 Valence band edge 34 Conduction band edge 41 Cladding layer 42 Active layer 42a First semiconductor layer 42b Second semiconductor layer 51 Third semiconductor layer 61 Cladding layer 62 Active layer 62a First active layer 62b Second active layer 62c Third active layer 71 Cladding layer 72 Active layer 73 Protective film 81 Cladding layer 82 Active layer 83 Nitride layer 84 Protection Film 90 substrate 91 transparent electrode 92a p-type cladding layer 92b n-type cladding layer 93 active layer 94 semiconductor flake 95 light emitting film 96 insulator film 97 metal electrode 101a n-type cladding layer 101b p-type cladding layer 102 active layer 110 substrate 111 transparent electrode 112 clad layer 112a p-type region 112b n Region 113 Active layer 114 Semiconductor flake 115 Light emitting film 115a P-type layer 115b N-type layer 116 Metal electrode 120 Substrate 121 Transparent electrode 122 N-type semiconductor layer 123 Cladding layer 124 Active layer 125 Semiconductor flake 126 Light-emitting film 127 P-type semiconductor layer 128 Metal Electrode 130 Substrate 131 Transparent electrode 132 Cladding layer 133 Active layer 134 Semiconductor thin piece 135 Light emitting film 136 Metal electrode 140 Substrate 141 Transparent electrode 142 a Active layer 142 b Cladding layer 142 Semiconductor thin piece 143 Semiconductor particle 144 Light emitting film 145 Cold cathode 146 Gate 147 Insulator Cathode 149 Substrate 150 Substrate 151 First transparent electrode 152 Cladding layer 153 Active layer 153a First semiconductor layer 153b Second semiconductor layer 154 Semiconductor flake 155 Light emitting film 156 Second transparent electrode 157 Light emitting diode (LED) 158 Electrode 160 Substrate 161 Transparent electrode 162 First insulating layer 163 Semiconductor flake 164 Cladding layer 165 Active layer 166 Semiconductor particles 167 Light emitting film 168 Second insulator layer 169 Back electrode 170 Substrate 171 Transparent electrode 172 Light emitting film 173 Semiconductor flake 174 Cladding layer 175 Active layer 176 Binder 177 Back electrode 180 Substrate 181 Semiconductor separation layer 182 Cladding layer 183 Active layer 184 Semiconductor film 185 Semiconductor flake 186 Solvent 187 Non-semiconductor substrate 188 Light-emitting film 190 On-semiconductor film 192 Non-semiconductor film 192 Separation layer 193 Cladding layer 194 Active layer 195 Semiconductor flake 200 Substrate 201 Transparent electrode 202 N-type impurity 203 Cladding layer 203a Diffusion layer 204 Active layer 205 Semiconductor flake 2 6-emitting layer 207 metal electrodes

Claims (3)

(57) [Claims] A light emitting film is formed by laminating a semiconductor thin film comprising a layered cladding layer and an active layer sandwiched between the cladding layers into a single layer or a multilayer , and the forbidden band width of the cladding layer is reduced. Semiconductor light emission having a band gap of the active layer or more
An apparatus, wherein the semiconductor flake is formed on the crystal growth substrate.
Layer and a semiconductor film having the active layer, the crystal growth substrate
The luminescent film is formed by pulverization after separation from the substrate, and the luminescent film is formed by coating the pulverized semiconductor flake on a substrate.
A semiconductor light emitting device characterized by being formed with a cloth . 2. A semiconductor separation layer made of a first semiconductor material on a substrate for crystal growth, and a first clad layer made of a semiconductor material different from the first semiconductor material and an active layer on this semiconductor separation layer. A first step of alternately growing a crystal and a semiconductor flake layer comprising a second cladding layer; and a second step of removing the semiconductor separation layer by selective etching.
A third step of pulverizing the semiconductor flake layer into semiconductor flakes;
And a fourth step of coating and fixing the semiconductor flakes in a film form on a substrate for forming a light emitting body and fixing the semiconductor flakes. 3. The semiconductor light emitting device according to claim 2, further comprising a fifth step of forming a pn junction by diffusing an impurity into the semiconductor flake, following the fourth step. Production method.