JPH1187843A - Surface-emitting semiconductor light-emitting device - Google Patents

Abstract

(57) Abstract: A surface-emitting type semiconductor light-emitting device having three terminals including a control terminal is provided. A p-type semiconductor thin film laminated on a substrate, i.
Light emitting units 15, 16, 17 including a pn structure or a pin structure formed of a type thin film or an n-type semiconductor thin film, and light emitting units 15, 1
A first contact layer 13 laminated on the substrate 11 side with respect to 6 and 17; a second contact layer 18 laminated on the substrate 11 above the light emitting portion; and a second contact layer 18 The semiconductor device includes a semiconductor layer 21 serving as an emitter layer or a collector layer further stacked as a base layer, and a third contact layer 13 stacked on the semiconductor layer 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a surface-emitting type semiconductor light emitting device. More particularly, the present invention relates to a semiconductor light-emitting device, and more particularly to a novel surface-emitting semiconductor light-emitting device that can be advantageously used in a two-dimensional arrangement to form a display device or the like.

[0002]

2. Description of the Related Art A semiconductor light-emitting device having a so-called pin structure formed of a semiconductor material deposited on a substrate includes:
Applications are being made not only as a light source for illumination but also in many fields such as a transmitter for optical communication and a thin display device.

FIG. 3 is a diagram showing a typical cross-sectional structure of a typical surface-emitting type semiconductor light emitting device as this type of semiconductor light emitting device.

[0004] As shown in FIG.
On the n-type multilayer reflective film 12, the n-type contact layer 13, the n-type clad layer 15, the light-emitting layer 16, the p-type clad layer 17, the p-type contact layer 18, and the dielectric multilayer reflective film 26 sequentially laminated on It is mainly composed and constitutes a so-called ipn structure. In addition, on both sides of the light emitting layer 16, high resistance regions 23 for current confinement are arranged. Further, an n-type ohmic electrode 14 or a p-type ohmic electrode 19 is loaded on the n-type contact layer 13 and the p-type contact layer 18, respectively. When a current flows between these electrodes, the light output from the light emitting layer 16 is taken out from the substrate 11 side.

[0005]

The above-described surface-emitting type device is, for example, a flat-panel display device provided that a plurality of devices are two-dimensionally arranged so that each device can be individually turned on and off. Etc. can be configured and used.

FIG. 4 is a view showing a configuration example of a light emitting element array in which a plurality of the surface emitting elements shown in FIG. 3 are arranged.

As shown in FIG. 1, the light-emitting element array is configured by arranging the surface-emitting light-emitting elements 35 shown in FIG. Here, one terminal of each light emitting element 35 is connected to a common ground terminal 34. This requires dissipating the heat generated by the light-emitting elements when a plurality of such light-emitting elements are integrated, so it is necessary to connect one of the terminals of each light-emitting element to ground, which also serves as a heat radiating means. Because it becomes.

However, when one of the two terminals of the surface-emitting type light emitting element is connected to a common ground, each element has only one controllable terminal. Therefore, the higher the degree of integration, the more difficult it is to select an arbitrary light-emitting element from the two-dimensionally arranged light-emitting elements and individually blink them.

Therefore, in order to control the blinking of each light emitting element, a three-terminal element 36 as a switch must be added to each light emitting element as shown in FIG. However, in practice, there are various difficulties in process technology to form a light emitting element and a transistor on a single substrate. Further, since the light emitting element and the transistor must be electrically and optically insulated, there is a problem that the number of manufacturing steps is further increased.

The present invention has been made to solve the above-mentioned problems of the prior art, and to provide a novel structure of a light emitting element capable of forming a two-dimensional light emitting element array capable of blinking individually for each light emitting element. For that purpose.

[0011]

According to the present invention, an npn structure, a nipin structure, and a p-type semiconductor thin film, an i-type thin film, or an n-type semiconductor thin film laminated on a substrate are provided.
nipn structure, pnp structure, pinip structure or pi
a light emitting unit including an np structure, a first contact layer stacked on the substrate side with respect to the light emitting unit, a second contact layer stacked above the light emitting unit with respect to the substrate, A semiconductor layer serving as an emitter layer or a collector layer further laminated using the second contact layer as a base layer; and a third contact layer laminated on the semiconductor layer, wherein the first and third contact layers are The light generated from the light emitting portion is emitted in the thickness direction of the substrate by flowing a current between the first and third light emitting portions, and the first and third light are emitted by carriers injected into the second contact layer. A surface-emitting type semiconductor light-emitting device is provided which is configured to control the amount of current flowing between contact layers.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The main feature of the light-emitting device according to the present invention is that it is configured as a so-called three-terminal device such as a transistor.

That is, as described above, since the conventional surface-emitting type light-emitting elements have two terminals, it is difficult to control individually, especially when two-dimensionally arranged. There is also a problem in manufacturing a light emitting element and a control transistor by a series of processes.

On the other hand, the surface-emitting type light emitting device according to the present invention has a light emitting device itself configured as a three-terminal device, and has two controllable terminals even if one terminal is connected to the ground. Will remain. Therefore, by controlling these two terminals, a two-dimensional array capable of blinking individually can be formed.

Further, since the surface emitting light emitting device according to the present invention can be manufactured by using the same process as a general surface emitting light emitting device, an increase in cost and a decrease in yield due to limitations in the manufacturing process are not caused. Virtually no.

FIG. 1 is a sectional view showing a specific configuration example of a surface-emitting type semiconductor laser device according to the present invention, and its light-emitting portion is of a so-called nipn type.

As shown in FIG. 1, this semiconductor laser device comprises an n-type multilayer reflective film 12, n
Type contact layer 13, n-type cladding layer 15, light emitting layer 16, p-type cladding layer 17, p-type contact layer 18, p-type buffer layer 2
0, an n-type emitter layer 21, an n-type contact layer 13, and an n-type multilayer reflective film 22. In addition, on the sides of the n-type cladding layer 15, the light-emitting layer 16 and the p-type cladding layer 17, and the sides of the n-type emitter layer 21 and the n-type contact layer 13, leakage current not contributing to light emission is reduced. The high-resistance layer 23 is disposed on the substrate. Further, the n-type contact layer 13
Is loaded with an ohmic electrode.

In the surface-emitting light emitting device having the above structure, the n-type multilayer reflective film 12, the n-type contact layer 13, and the n-type
The mold clad layer 15, the light emitting layer 16, the p-type clad layer 17, the p-type contact layer 18, and the n-type multilayer reflective film 22 have the same functions as the two-terminal light-emitting device shown in FIG. That is, n
By causing a current to flow between the mold contact layer 13 and the p-type contact layer 18, the light-emitting layer 16 emits light and light output can be taken out from the substrate 11 side.

Further, in the light emitting device shown in FIG. 1, in addition to the p-type contact layer 18 as the base,
The 21 and the n-type contact layer 13 operate as a transistor, so to speak. Therefore, this semiconductor laser device can be operated as a three-terminal device including a pair of n-type contact layers 13 and a single p-type contact layer 18 as a whole.

A surface emitting light emitting device having the structure shown in FIG. 1 was manufactured using the following materials.

N-type contact layer: n ⁺ InGaAsP (5 × 10
¹⁸ cm ^-3 , 0.2 μm), n-type cladding layer: n ^- InP (5 × 10 ¹⁷ cm ^-3 , 0.1 μm)
And n ^- InGaAsP (5 × 10 ¹⁶ cm ⁻³ , 0.05 μm, λ _g =
1.2 μm), light-emitting layer: i ^- InGaAsP (non-doped, 0.02 μm, λ _g =
1.31 μm) and p ^- InGaAsP (5 × 10 ¹⁶ cm ⁻³ , 0.03 μm)
_{m, λ g = 1.2 μm)} p -type cladding ^{layer: p - InP (7 × 10} 17 cm -3, 0.1μm) p -type contact ^{layer: p + InGaAsP (5 × 10} 18 cm -3, 0.01
μm), p-type buffer layer: p ^- InP (1 × 10 ¹⁸ cm ⁻³ , 0.12 μm)
_{m, λ g = 1.2 μm)} n -type emitter ^{layer: n - InP (8 × 10} 17 cm -3, 0.2μm,
λ _g = 1.2 μm) n-type contact layer: n ⁺ InGaAsP (5 × 10 ¹⁸ cm ⁻³ , 0.2
μm) p-type ohmic electrode: AuZn (alloyed at 450 ° C for 60 seconds), n-type ohmic electrode: AuGe / Ni / Au (alloyed at 450 ° C for 60 seconds)

As the n-type multilayer reflection films 12 and 22, n-InP / n-InGaAsP superlattices each having a thickness of 1/4 wavelength were used. The n-type multilayer reflective film 12 on the substrate 11 side was 34 pairs, and the n-type multilayer reflective film 22 on the far side from the substrate 11 was 20.5 pairs.
The light emitting surface is a circle having a diameter of 10 μm. The total thickness of the p-type semiconductor was one wavelength. Further, the total thickness of the n-type epitaxial layers on both sides of the active layer excluding the n-type reflection film was also set to one wavelength. As described above, by setting the thickness of each of the p-type and n-type epitaxial layers or the distance between the active layer and the reflective layer to be an integral multiple of the wavelength, the light can be amplified at the position where the amplitude of light is largest, and a higher output can be obtained. Can be

In the light emitting device of the present invention configured as described above, an output of 0.2 mW was obtained even at room temperature. On the other hand, for comparison, a light emitting device having a conventional structure shown in FIG. 3 was also manufactured. The light emitting device of this conventional structure has 5.5 pairs of Si (1/4 wavelength thickness) / SiO instead of the n-type multilayer reflective film on one side.
₂ Except for using a (thickness 1/4 wavelength) dielectric multilayer film, it has the same specifications as the light emitting device of the present invention,
Again, an optical output of 0.2 mW or more was obtained. That is, even with the light emitting device according to the present invention, a light output equivalent to that of the conventional structure was obtained.

A plurality of light emitting devices according to the present invention as described above can be arranged in a matrix to form a light emitting device array.

FIG. 2 is a diagram showing a basic configuration of a light emitting element array in which the above light emitting elements are arranged two-dimensionally.

As shown in the figure, in this light emitting element array, one of the three terminals of each light emitting element 31 is connected to a common ground terminal 34. One of the remaining two terminals is a row selection terminal 32 arranged at the end of each row.
Are connected for each row. Further, the remaining one terminal is connected to a column selection terminal 33 arranged at an end of each column for each column. Therefore, the light emitting elements at the positions where the selected row selection terminal and column selection terminal intersect can be individually turned on.

In the above description, the light-emitting portion of the light-emitting element has an example having a so-called nip-type layer structure. However, the surface-emitting light-emitting device according to the present invention is constituted by another light-emitting portion. You can also. That is, npn structure, nipi
A material that constitutes a light emitting portion such as an n structure, a nipn structure or a pnp structure, a pinip structure, and a pinp structure, and becomes a light emitting layer only on the side of the two pn structures or the pin structures included therein that is biased in the forward direction. May be used. It should not be difficult for those skilled in the art to manufacture a three-terminal light emitting device having another configuration in this way.

In the above embodiment, two semiconductor multilayer reflective films are used. However, the present invention is not limited to this configuration. It is also possible to use a coated antireflection film. In this case, the light emitting element operates as a surface emitting light emitting diode, and the light density on the light output surface can be reduced. Therefore, high reliability can be obtained although the light output is low.

Further, by forming the pn structure or the pin structure on the side to be reverse-biased using a material which is transparent with respect to the emission wavelength, a high-output surface-emitting type light emitting device with less loss inside the resonator. An element can be realized.

On the other hand, by forming the pn structure or the pin structure on the side to be reverse-biased using a material which becomes an absorber for the emission wavelength, the emission power is monitored or the output light is modulated by an external signal. Or the function of

[0031]

As described above in detail, the surface-emitting type light emitting device according to the present invention itself is a three-terminal device. In particular, when two-dimensionally arranged, the light emitting device blinks. Address selectivity controlled individually can be provided. Therefore, it can be widely used as a light source for a multi-channel optical transmitter, a flat panel display, or the like.

In addition, the manufacturing process can be applied to a general light emitting device process without any change, so that there is no manufacturing problem.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration example of a semiconductor laser as a specific configuration example of a surface emitting semiconductor light emitting device according to the present invention.

FIG. 2 is a diagram showing a basic configuration of a semiconductor laser array configured using the semiconductor laser shown in FIG.

FIG. 3 is a diagram showing a typical configuration of a conventional surface-emitting type light-emitting device by a cross section of a semiconductor laser device.

FIG. 4 is a diagram showing a configuration of a light emitting element array configured using the conventional surface emitting light emitting element shown in FIG.

[Explanation of symbols]

11 ... substrate, 12 ... first n-type multilayer reflective film, 13 ... n ⁺ contact layer, 14 ... n-type ohmic electrode, 15 ... n-type clad layer, 16 ... active layer (Light-Emitting Region), 17 ... p-type cladding layer, 18 ... p ⁺ contact layer, 19 ... p-type ohmic electrode, 20 ... p-type buffer layer, 21 ... n-type emitter layer, 22: second n-type multilayer reflective film, 23: high-resistance region, 24: high-resistance region, (for current confinement), 25: metal layer for heat radiation, 26: dielectric Multi-layer reflective film, 31: Surface emitting type three terminal light emitting element, 32: First control electrode, 33: Second control electrode, 34: Ground electrode, 35: Surface emitting type two terminal Light emitting element, 36 ... Transistor for address selection,

Claims (6)

[Claims] 1. An npn structure, a nipin structure, a nipn structure, a pnp structure, and a pi structure formed of a p-type semiconductor thin film, an i-type thin film or an n-type semiconductor thin film laminated on a substrate.
a light emitting unit including a nip structure or a pinp structure, a first contact layer stacked on the substrate side with respect to the light emitting unit,
A second contact layer stacked on the substrate above the light emitting portion, a semiconductor layer serving as an emitter layer or a collector layer further stacked using the second contact layer as a base layer, and the semiconductor layer And a third contact layer laminated on the substrate, wherein a light generated from the light emitting portion is emitted in a thickness direction of the substrate by flowing a current between the first and third contact layers. And a structure in which the amount of current flowing between the first and third contact layers can be controlled by carriers injected into the second contact layer. apparatus. 2. The semiconductor light emitting device according to claim 1, further comprising a resonator including a pair of reflecting mirrors formed of a semiconductor multilayer film or a dielectric multilayer film having the same polarity, and a surface emitting type. A semiconductor light-emitting device comprising a semiconductor laser. 3. The semiconductor light emitting device according to claim 1, wherein a high reflection film and an antireflection film formed of a semiconductor multilayer film or a dielectric multilayer film having the same polarity are provided at both ends of the waveguide. A semiconductor light emitting device comprising a surface emitting light emitting diode. 4. The semiconductor light-emitting device according to claim 1, further comprising a light-emitting layer only on a forwardly biased side of a pn structure or a pin structure included in said light-emitting portion, and being reverse-biased. A surface-emitting type semiconductor light-emitting device characterized in that a material transparent to an emission wavelength is used for the pn structure or the pin structure. 5. The semiconductor light-emitting device according to claim 1, further comprising a light-emitting layer only on a forwardly biased side of a pn structure or a pin structure included in said light-emitting portion, and being reverse-biased. A surface-emitting type semiconductor light-emitting device characterized in that a material serving as an absorber for an emission wavelength is used for the pn structure or the pin structure. 6. A semiconductor light-emitting device according to claim 1, wherein a plurality of the semiconductor light-emitting devices are arranged in a matrix, and each of the first terminals of the semiconductor light-emitting device is connected to a common ground. Terminals connected to the same row of the semiconductor light emitting devices, the second terminals of the semiconductor light emitting devices are connected to a row selection terminal assigned to each row, and the semiconductor light emitting devices arranged in the same column. By connecting each third terminal to a column selection terminal assigned to each column and connecting an arbitrary row selection terminal and a column selection terminal to a power source, the semiconductor light emitting element arranged at an arbitrary address can be selectively selected. A semiconductor light emitting device array characterized in that it can be turned on.