JP3644226B2 - Surface-emitting semiconductor light-emitting element, surface-emitting semiconductor light-emitting element array, image forming apparatus, and image display apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a surface-emitting type semiconductor light emitting device, and more specifically, a surface emitting type such as a surface emitting type semiconductor laser used as a light source for a laser printer, a laser display, and an optical communication device and an optical signal processing device. The present invention relates to a semiconductor light emitting element, a surface light emitting semiconductor light emitting element array formed by arranging surface light emitting semiconductor light emitting elements in a matrix, and an image forming apparatus and an image display apparatus using the surface light emitting semiconductor light emitting element array as a light source.
[0002]
[Prior art]
A surface emitting semiconductor laser is a device that sandwiches an active region with a multilayer mirror, reflects light generated in the active layer with a multilayer mirror, amplifies the light, and causes laser oscillation. In order to inject current into the active layer, one multilayer mirror is usually made n-type conductive and the other is made p-type conductive, and current is passed through them to inject current into the active layer.
[0003]
In a laser array in which a large number of surface-emitting semiconductor lasers are arranged, it is cumbersome because the number of wires required for each laser is the same as the number of lasers, so matrix wiring is required. Is done. For example, when wiring individual electrodes to a 10-row × 30-column laser array, the cathode electrode is a common electrode on a conductive substrate, and only 300 anode electrodes are wired for 300 individual lasers. become. In contrast, in the matrix wiring, the substrate is semi-insulating, and 10 anode wirings are formed in the row direction of the laser array and 30 cathode wirings are formed in the column direction, and individual lasers are arranged at the intersections. do it. The total number of wires can be 40. From this point of view, matrix wiring is adopted for many laser arrays.
[0004]
However, as shown in FIG. 14, the anode wiring 138 and the cathode wiring 136 of the surface emitting laser array are normally formed in the uppermost layer and the lowermost layer of the surface emitting laser, so that the electrodes are formed in the lowermost layer. In this case, the stack of surface-emitting lasers formed on the semi-insulating GaAs substrate 120 must be etched to a thickness of 8 μm or more to expose the lowermost GaAs buffer layer 122. Reference numeral 124 denotes an n-type multilayer mirror, 126 denotes an active region, 128 denotes a p-type multilayer mirror, and 132 denotes polyimide.
[0005]
It is not technically easy to form the cathode electrode 136 on the deep concavo-convex shape formed by such etching and route the wiring. Since the diameter of the convex shape of the surface emitting laser is required to be about 20 μm at the minimum, when the arrangement pitch of the laser array is narrower than 45 μm, the groove width of the gap of the surface emitting laser is 25 μm. When the depth of the groove is 8 μm or more, it is extremely difficult to dig the element isolation groove 130 in such a narrow and deep concave groove bottom, take a process margin width L, and further form the cathode wiring 136. It is difficult and almost impossible with the current photolithography technology level. Since both the margin width L and the electrode width α need to be 5 μm, the arrangement pitch of the surface emitting laser array cannot be 45 μm or less. In other words, it is difficult to narrow the arrangement pitch of the surface emitting laser array with matrix wiring, and it must be relatively wide. Therefore, low cost, high reliability, and high performance are achieved by high density integration. There is a problem that is difficult.
[0006]
On the other hand, Japanese Patent Application Laid-Open No. 5-243552 reports a technique relating to an optoelectronic integrated circuit in which a surface emitting semiconductor laser and a transistor are stacked. Similarly, Japanese Laid-Open Patent Publication No. 7-503104 proposes a structure of a photoelectric integrated circuit in which a surface emitting laser and a transistor are stacked. In both of these technologies, a transistor and a surface emitting laser are stacked, and the driving of the surface emitting laser is controlled by the transistor. These documents describe a method in which surface-emitting lasers on which transistors are mounted are arranged two-dimensionally and driven by applying matrix wiring to the transistors.
[0007]
However, when a surface emitting laser and a transistor are stacked, the following problem occurs. That is, when the transistor is disposed at the light extraction port of the surface emitting laser, the laser light is absorbed by the transistor and almost no light is emitted. Even if the band gap of the transistor is set larger than that of the laser beam to avoid this, the collector layer, base layer, and emitter layer of the transistor are sequentially laminated on the multilayer reflection layer of the surface emitting laser. The periodicity of the mirror configuration is broken, and as a result, the reflectivity is lowered and the output characteristics of the laser are lowered.
[0008]
Therefore, in order to stack the surface emitting laser and the transistor, it is necessary to install the transistor on the side opposite to the laser light extraction port. That is, when a transistor is stacked on a surface emitting laser, light must be extracted from the back surface of the substrate, and when a surface emitting laser is stacked on the transistor, light must be extracted from the surface side of the substrate. FIG. 15 shows the structure of a surface emitting laser array equipped with a conventional transistor. When the wavelength of the laser beam does not pass through the GaAs substrate on which the surface emitting laser and the transistor are stacked, specifically, when the wavelength of the light is shorter than 880 nm, the light must be extracted from the surface side of the GaAs substrate. As shown in FIG. 15, a transistor including an emitter layer 150, a base layer 152, a collector layer 154, an emitter electrode 156, and a base electrode 158 is stacked on a GaAs substrate 168, and an n-type multilayer film is formed thereon. A structure in which a surface emitting laser having a mirror 162, an active region 166, a p-type multilayer mirror 164, and a p-type electrode 160 is stacked must be taken. In this case, the transistor is etched to a depth of about 8 μm, the base layer and the emitter layer are exposed, electrodes are formed on the two layers, and the matrix wiring is routed.
[0009]
Thus, it is a more difficult technique to form a matrix wiring for the emitter and base at the bottom of the groove having a depth of 8 μm than a normal matrix wiring (FIG. 14). In the laser array having such a configuration, the arrangement pitch of the laser elements cannot be made narrower than that of a laser array provided with a normal matrix wiring.
[0010]
In the etching exposure of the emitter layer and the base layer, the etching is accurately stopped at a depth of 8 μm to expose the emitter layer (thickness 0.2 μm), and then the emitter layer 0.2 μm is etched to etch the base layer. (0.2 μm) must be exposed. Since the base layer is only about 0.1 μm, the etching depth must be controlled with extremely high precision. In reality, however, deep etching of about 8 μm is controlled with an accuracy of 0.1-0.2 μm. Is extremely difficult.
[0011]
As is apparent from the above, in the technique of stacking a transistor and a surface emitting laser, the laser elements cannot be arranged at a narrow pitch in a surface emitting laser array that outputs light of a short wavelength that does not pass through a GaAs substrate. There is. That is, it is difficult to narrow the arrangement pitch of the surface emitting laser array with matrix wiring, and it must be relatively wide. Therefore, it is difficult to reduce the cost and increase the reliability by high-density integration. There is.
[0012]
[Problems to be solved by the invention]
The matrix wiring of the two-dimensional surface-emitting laser array has its anode wiring and cathode wiring formed on the uppermost layer and the lowermost layer of the surface-emitting laser. It was necessary to form an electrode on the bottom and route the wiring, which was technically difficult. In particular, when the arrangement pitch of the laser array is narrowed to about 45 μm or less, it is difficult to perform the photolithography technique to the narrow and deep groove bottom, and it is extremely difficult to form electrodes and route wiring.
[0013]
In addition, in a surface emitting semiconductor light emitting device in which a conventional transistor is stacked on the light emitting side of a surface emitting laser, the periodicity of the multilayer mirror of the surface emitting laser is broken by the collector layer, base layer, and emitter layer of the transistor, so that reflection occurs. There was a problem that the output rate was lowered and the laser output characteristics were lowered.
[0014]
Therefore, in order to extract light from the surface side of the substrate when the laser light does not pass through the substrate even if a method of driving by a two-dimensionally arranged transistor is used instead of directly driving the surface emitting laser array. A transistor must be inserted under the surface emitting laser, and it is more difficult to form a matrix wiring for the transistor than to form a matrix wiring in a conventional surface emitting laser array. .
[0015]
As described above, there is a problem that it is extremely difficult to arrange the light emitting elements of the surface emitting light emitting element array such as the surface emitting laser array provided with the matrix wiring at a narrow pitch.
[0016]
The present invention has been made in view of such circumstances, and a first object thereof is to provide a surface-emitting type semiconductor light-emitting device having excellent output characteristics.
[0017]
It is a second object of the present invention to provide a surface light emitting semiconductor light emitting element array that allows easy matrix wiring and high density integration.
[0018]
A third object of the present invention is to provide an image forming apparatus capable of forming a high resolution image.
[0019]
A fourth object of the present invention is to provide an image display device capable of displaying a high-resolution image.
[0020]
[Means for Solving the Problems]
In order to achieve the first object, the invention described in claim 1 includes a first multilayer mirror layer, a first spacer layer, an active region, a second spacer layer, a first spacer layer on a semiconductor substrate. In a surface-emitting type semiconductor light emitting device in which two multilayer mirror layers are arranged in this order, a third layer having a conductivity type different from that of each of the layers except the active region is inserted. Thus, a semiconductor layer constituting a switching element composed of the inserted layer and the third layer is formed in the light emitting element.
[0021]
According to a second aspect of the present invention, a first multilayer mirror layer, a first spacer layer, an active region, a second spacer layer, and a second multilayer mirror layer are formed on a semiconductor substrate. Arranged in this order, at least one of the first multilayer mirror layer and the first spacer layer has the first conductivity type, and at least one of the second spacer layer and the second multilayer mirror layer has the first conductivity type. In a surface-emitting type semiconductor light emitting device having a second conductivity type opposite to the first conductivity type, a third layer of the second conductivity type is inserted into or inside the layer having the first conductivity type. Or a semiconductor layer constituting a switching element is formed by inserting a third layer of the first conductivity type into the inside or end of the layer having the second conductivity type,
A first electrode formed in a layer having a first conductivity type below the third layer; and a second electrode formed in a layer having a second conductivity type above the third layer. The light emission can be controlled by driving the electrode and a third electrode formed on the third layer or a contact layer formed on the third layer.
[0022]
According to a third aspect of the present invention, a first multilayer mirror layer, a first spacer layer, an active region, a second spacer layer, and a second multilayer mirror are formed on a conductive semiconductor substrate. Are arranged in this order, the conductive semiconductor substrate and the first multilayer mirror layer have the first conductivity type, and at least one of the second spacer layer and the second multilayer mirror layer is the first In the surface-emitting type semiconductor light emitting device having the second conductivity type opposite to the first conductivity type, the second conductivity type having the second conductivity type inside or at the end of the first multilayer mirror layer having the first conductivity type. Inserting a third layer of the second conductivity type, or inserting a third layer of the first conductivity type into the inside or the end of the second multilayer mirror layer having the second conductivity type Forming a semiconductor layer constituting the switching element by the first electrode formed on the conductive substrate; Driving the second electrode formed on the second conductive type layer on the upper side and the third electrode formed on the third layer or the contact layer formed on the third layer The light emission can be controlled by the above.
[0023]
According to a fourth aspect of the present invention, in the surface-emitting type semiconductor light emitting device according to any one of the first to third aspects, each of the first and second multilayer mirror layers has a thickness λ / (4 ・ n_i(Λ is the wavelength of light emitted from the active layer, n_iIs composed of a laminated structure of layers, and the first spacer layer, the second spacer layer, and the active region have a thickness t of each layer._iIs the refractive index n of each layer_iValue t multiplied by_i・ N_iThe third layer is formed so as to maintain the above-described configuration of the layer in which the third layer is inserted.
[0024]
According to a fifth aspect of the present invention, in the surface-emitting type semiconductor light-emitting device according to the fourth aspect, the third layer is the first multilayer mirror layer or the inside or the end of the second multilayer mirror layer. And the third layer is formed so as to maintain the periodicity of the configuration of the multilayer mirror layer in which the third layer is inserted.
[0025]
In the surface-emitting semiconductor light-emitting device having the above-described configuration, a multilayer film having a different conductivity type, which is a third layer, is provided inside or below the surface-side multilayer mirror layer (reflective layer) constituting the surface-emitting laser. By inserting a mirror layer (hereinafter, this layer is called a drive switch layer), a switching element, for example, a pnp junction or npn junction semiconductor layer constituting a transistor is formed on the surface side constituting the surface emitting laser. . Then, electrodes are formed on the conductive substrate, the multilayer mirror layer on the surface side, and the drive switch layer, and the surface emitting laser is driven by manipulating the potential or current value of these three electrodes. In this case, the drive switch layer is formed so as to maintain the periodicity of the arrangement of the multilayer mirror layers on the surface side.
[0026]
Therefore, even if the drive switch layer is inserted, the output characteristics of the surface emitting laser can be improved as compared with the conventional one without reducing the reflectivity of the multilayer mirror layer as the reflective layer.
[0027]
In the surface-emitting type semiconductor light emitting device, since the electrodes are formed on the conductive substrate, the multilayer mirror layer on the surface side, and the drive switch layer, a common electrode is formed on the conductive substrate, and the multilayer mirror layer on the surface side is formed. By applying matrix wiring to the drive switch layer, a laser array can be configured and each surface emitting laser of this laser array can be driven independently. Since such matrix wiring is formed on the substrate surface with almost no unevenness, it can be easily formed and can be applied to a laser array arranged at a narrow pitch.
[0028]
In order to achieve the second object, the invention according to claim 6 is the one in which the surface-emitting type semiconductor light-emitting elements according to any one of claims 2 to 5 are two-dimensionally arranged, and One of the two electrodes is used as a common electrode, and a matrix wiring is formed for the other electrode and the third electrode of the first electrode or the second electrode, and the three electrodes It is characterized in that each surface-emitting semiconductor light-emitting element can be driven by an electrode.
[0029]
According to the surface-emitting type semiconductor light-emitting element array having the above configuration, since the matrix wiring can be formed on the substrate surface with almost no unevenness, the matrix wiring is easy and the density of the matrix wiring can be increased. Therefore, high-density integration of the surface-emitting type semiconductor light-emitting element can be achieved.
[0030]
In order to achieve the third object, the invention described in claim 7 uses the surface-emitting type semiconductor light-emitting element array described in claim 6 as a light source, and prints an image using the light emitted from the light source. It is characterized by that.
[0031]
In the image forming apparatus having the above configuration, the surface-emitting type semiconductor light emitting element array integrated with high density is used as the light source, so that the pixel pitch can be reduced and a high resolution image can be formed.
[0032]
In order to achieve the fourth object, the invention according to claim 8 is directed to a display surface using the surface-emitting type semiconductor light-emitting element array according to claim 6 as a light source, and using the optical system for the light emitted from the light source. And displaying a still image or a moving image.
[0033]
In the image display device having the above-described configuration, the surface-emitting type semiconductor light-emitting element array integrated with high density is used as the light source. Therefore, the pixel pitch can be reduced, and thus a high-resolution image can be displayed.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings.
[0035]
First embodiment
FIG. 1 shows the structure of a surface-emitting type semiconductor light-emitting device according to the first embodiment of the present invention. In this figure, an n-type GaAs buffer layer 12 (0.2 μm thick, carrier concentration 2 × 10 6) is formed on a Si-doped n-type GaAs substrate 10 by MOCVD (Metal Organic CVD).¹⁸/cm^Three), N-type Al_0.3Ga_0.7As / Al_0.9Ga_0.1As multilayer mirror layer 14 (57.6nm / 64.5nm × 40.5 period, carrier concentration 2 × 10¹⁸/cm^Three), Al_0.6Ga_0.4As spacer layer 16 (89.8nm, non-doped), Al_0.11Ga_0.89As / Al_0.3Ga_0.7Active region 18 of As (quantum well layer / barrier layer 8nm / 5nm × 4 period, non-doped), Al_0.6Ga_0.4As spacer layer 20 (89.8 nm, non-doped), p-type Al_0.3Ga_0.7As / Al_0.9Ga_0.1As multilayer mirror layer 22 (57.6nm / 64.5nm × 23.5 period, carrier concentration 2 × 10¹⁸/cm^Three) Will grow sequentially.
[0036]
On top of that, n-type Al_0.3Ga_0.7As / Al_0.9Ga_0.1As / Al_0.3Ga_0.7As (57.6nm / 64.5nm / 57.6nm, carrier concentration 2 × 10¹⁸/cm^Three) Is grown, and the p-type Al is again formed thereon._0.3Ga_0.7As / Al_0.9Ga_0.1As multilayer mirror layer 24 (57.6nm / 64.5nm × 4 periods, carrier concentration 6 × 10¹⁸/cm^Three) And p-type contact layer 26 (9 nm, carrier concentration 1 × 10 6)¹⁹/cm^Three) Grow. Here, the laminated interface of each multilayer mirror layer was a graded layer with a gradually changing composition to reduce electrical resistance. N-type Al_0.3Ga_0.7As / Al_0.9Ga_0.1As multilayer mirror layer 14 is the first multilayer mirror layer of the present invention, Al_0.6Ga_0.4As spacer layer 16 is the first spacer layer of the present invention, active region 18 is the active region of the present invention, Al_0.6Ga_0.4The As spacer layer 20 is a p-type Al layer on the second spacer layer of the present invention._0.3Ga_0.7As / Al_0.9Ga_0.1As multilayer mirror layer 22 and p-type Al_0.3Ga_{0 .7}As / Al_0.9Ga_0.1The As multilayer mirror layer 24 corresponds to the second multilayer mirror layer of the present invention, and the drive switch layer 28 corresponds to the third layer of the present invention.
[0037]
The thickness t of each of the multilayer mirror layers 14, 22, 24 and the drive switch layer 28_iIs t for light of the laser wavelength λ (here 780 nm)_i= Λ / (4 ・ n_i) (N)_iIs the refractive index of each layer), and high reflectivity is achieved. Further, each of the spacer layers 16 and 20 and the active region 18 has a thickness t of each layer._iAnd refractive index n_iMultiplied by t_i× n_iIs set to be equal to λ, and serves as a laser resonator.
[0038]
Next, protons were injected into the surface emitting laser structure layer having such a stacked structure to electrically separate individual laser elements, and at the same time, a current confinement structure was formed in the vicinity of the active region 18. As shown in FIG. 1, the method uses protons (H) so that the diameter of the current constriction is 5 μm.⁺). The acceleration voltage of proton irradiation was changed to about several hundred kV, and the proton injection region was allowed to reach the n-type multilayer mirror layer 14 below the active region 18. By forming the proton injection region in this manner, the active region 18 of the laser element and the p-type multilayer mirror layers 22 and 24 and the drive switch layer 28 above the insulating region are insulated from the adjacent laser element, and are electrically Separated. After proton injection, heat treatment was performed to restore crystallinity.
[0039]
Next, a silicon oxide film having a film thickness of 0.2 μm is deposited on the outermost surface of the laser structure layer, patterned, and a part of the p-type contact layer 26 and the p-type multilayer mirror layer 24 is etched as shown in FIG. By removing, a part of the drive switch layer 28 is exposed. On the exposed surface of the drive switch layer 28, an n-type GaAs drive switch contact layer 30 (carrier concentration 2 × 10¹⁸/cm^Three) Is selectively grown to a thickness of 0.1 μm.
[0040]
Finally, the drive switch electrode 36 (the third electrode of the present invention) and the p-type electrode 34 (the first electrode of the present invention) are respectively applied to the n-type drive switch contact layer 30, the p-type contact layer 26, and the n-type GaAs substrate 10. 2) and an n-type electrode 32 (corresponding to the first electrode of the present invention). An AuGe alloy was used for the drive switch electrode 36 and the n-type electrode 32, and an AuZn alloy was used for the p-type electrode 34. The size of the p-type electrode 34 is, for example, 20 μm square, and a light exit opening with a diameter of 5 μm is perforated at the center.
[0041]
The drive characteristics of the surface-emitting type laser element (FIG. 1) as the surface-emitting type semiconductor light-emitting element manufactured as described above were examined by simulation. First, an equivalent circuit of the surface emitting laser element is shown in FIG. From the bottom, an equivalent circuit is described in the order of the n-type multilayer mirror layer 14, the active region 18 and the spacer layers 16 and 20, the p-type multilayer mirror layer 22, the n-type drive switch layer 28, and the p-type multilayer mirror layer 24. did. In the figure, the electric resistance is indicated by a symbol beginning with r, and the capacitance is indicated by a symbol beginning with c. Since the n-type drive switch layer 28 is inserted between the p-type multilayer mirror layer 22 and the p-type multilayer mirror layer 24, two pn junction diodes face the upper and lower interfaces. A semiconductor layer constituting a pnp junction transistor as a switching element is formed.
[0042]
From the detailed structure of the surface emitting laser element shown in FIG. 1 described above, the resistance value and capacitance of the equivalent circuit shown in FIG. 3 and the characteristics of the pn junction diode are determined, and the HSPICE simulator program is used. A simulation was performed.
[0043]
As a method for driving the surface emitting laser element, the potential V0 of the n-type electrode 32 is set to the ground level (0V), the potential V1 of the p-type electrode 34 is set to 10V, and only the potential V2 of the drive switch electrode 36 is set to 10V to 7.0V. Until changed. The current flow at that time is shown in FIG. As can be seen from FIG. 4, when the potential V2 of the drive switch electrode 36 becomes 8.5 V or less, current starts to flow from the p-type electrode 34 to the active region 18. At this time, the amount of current flowing through the drive switch electrode 36 is 1/8 of the value of current flowing from the p-type electrode 34 into the active region 18. However, when the potential V2 of the drive switch electrode 36 is about 8 V or less, the current flowing through the active region 18 is saturated, but the current flowing through the drive switch electrode 36 increases linearly. That is, when the potential V2 of the drive switch electrode 36 falls below 8V, the potential V2 contributes only to an increase in the current flowing through the drive switch electrode 36, and does not contribute to an increase in the current flowing through the active region 18. This is because when the potential V2 of the drive switch electrode 36 is 8 V or less, the valence band potential of the drive switch layer 28 does not serve as a barrier against holes that are majority carriers of the p-type multilayer mirror layer, and current flows easily. This is because the current flows out of the device from the p-type electrode 34 to the drive switch layer 28 and from the drive switch layer 28 to the drive switch electrode 36. Since the value of the current flowing into the active region 18 is proportional to the potential difference between the drive switch layer 28, that is, the drive switch electrode 36 and the n-type electrode 32, the lower the potential of the drive switch electrode 36 is 8V or less, the lower the p-type electrode Thus, current flows out to the drive switch electrode 36, and the current flowing through the active region 18 decreases. As described above, the drive switch layer 28 functions as a potential barrier against holes, which are majority carriers of the p-type multilayer mirror layer 22, in a state where no voltage is applied to each electrode, and functions to block the flow of holes. However, by raising and lowering the potential of the drive switch layer 28, that is, the drive switch electrode 36, the height of the potential barrier can be raised and lowered, and the current flowing through the active region 18 can be controlled.
[0044]
The operation principle will be described in detail with reference to FIG. In FIG. 2, if the potential of the n-type electrode 32a is the ground level (0V) and the potential of the p-type electrode 34a and the drive switch electrode 36a is 10V, the n-type electrode 32a is 0V in FIG. The drive switch layer 32a moves downward in the figure by 10ev. That is, the Fermi level of the p-type electrode 34a and the drive switch layer 28a is horizontal, and the Fermi level of the layer on the right side of the p-type multilayer mirror layer 22a is inclined upward.
[0045]
However, since the valence band of the drive switch layer 28a protrudes downward by about 2.0 V due to the built-in potential and forms a potential barrier, the holes in the p-type multilayer mirror layer 24a are converted into p-type multilayer mirrors. It cannot move to the layer 22a and no current flows. However, if the potential of the drive switch electrode 36a is set to 8.5V, the potential of the drive switch layer 28a moves 1.5eV above the p-type electrode 34a, and the potential barrier is lowered. And current begins to flow gradually. When the potential of the drive switch layer 28a is lowered to 8.0 V, the height of the potential barrier becomes substantially the same as the Fermi level of the p-type electrode 34a, and the holes are not disturbed by the potential barrier by the drive switch layer 28a. It can move to the mold multilayer mirror layer 22a. The value of the current flowing through the active region 18a is a value obtained by dividing the potential difference between the drive switch layer 28a and the n-type electrode 32a by the resistance value between the layers.
[0046]
Further, when the potential of the drive switch layer 28a is set to 8.0 V or less, the potential of the valence band becomes a depression on the upper side with respect to the p-type multilayer mirror layer 22a. That is, the current easily flows in the forward direction of the pn junction, and the current flows out of the device from the p-type electrode 34a to the drive switch layer 28a and from the drive switch layer 28a to the drive switch electrode 36a. Since the value of the current flowing through the active region 18a is proportional to the potential difference between the drive switch layer 28a and the n-type electrode 32a, it decreases as the potential of the drive switch layer 28a, that is, the drive electrode 36a decreases. That is, as the potential of the drive switch layer 28a, that is, the drive electrode 36a is lowered to 8.0 V or less, a current flows from the p-type electrode 34a to the drive switch electrode 36a, and a current value flowing through the active region 18 decreases.
[0047]
The simulation results have been described above with reference to FIG. 2. According to this simulation, in the surface-emitting laser as the surface-emitting semiconductor light-emitting device according to the first embodiment of the present invention, the n-type electrode 32a and It can be seen that current can be injected into the active region of the surface emitting laser by manipulating the potentials of the p-type electrode 34a and the drive switch electrode 36a. Of course, it goes without saying that the same effect can be obtained by operating the current values of these three electrodes.
[0048]
According to the surface-emitting type semiconductor light-emitting device according to the first embodiment of the present invention, the inside of the surface-side multilayer mirror layer (reflection layer) constituting the surface-emitting type laser device, or the lower side thereof, A semiconductor layer constituting a switching element (transistor) is formed on the surface side constituting the surface emitting laser by inserting a multilayer mirror layer (drive switch layer) having a different conductivity type, which is the third layer, and further conducting. The surface-emitting laser is driven by forming electrodes on the conductive substrate, the multilayer mirror tank on the surface side, and the drive switch layer, and by operating the potential or current value of these three electrodes. Since it is formed so as to maintain the periodicity of the arrangement of the multilayer mirror layers on the surface side, the reflectance of the multilayer mirror layer as the reflective layer does not decrease even when the drive switch layer is inserted. Improvement of the output characteristics of the surface emitting laser Te can be reduced.
[0049]
Since the drive switch layer is a part of the laser structure layer, the crystal growth is the same as that of a normal surface emitting laser and is simple. Further, since the drive voltage of the drive switch electrode and the p-type electrode may be a small change amount of about 1 V, there are effects such as high-speed modulation, low power consumption, and easy design of the drive circuit.
[0050]
Further, since a conductive (Si-doped) GaAs substrate can be used as a substrate for crystal growth of the laser structure layer, there are few defects and the yield can be improved.
[0051]
In the surface-emitting type semiconductor light emitting device, the electrodes are formed on the conductive substrate 10, the p-type contact layer 26 of the multilayer mirror layer 24 on the surface side, and the drive switch contact layer 30 of the drive switch layer 28. 10 is formed, and a matrix wiring is applied to the p-type contact layer 26 and the drive switch contact layer 30 on the surface side to form a laser array, and each surface emitting laser of this laser array is independently Can be driven. Since such matrix wiring is formed on the substrate surface with almost no unevenness, it can be easily formed and can be applied to a laser array arranged at a narrow pitch.
[0052]
Second embodiment
Next, FIG. 5 shows the structure of a surface-emitting type semiconductor light-emitting device according to the second embodiment of the present invention. The surface-emitting type semiconductor light-emitting device according to the present embodiment is structurally different from the surface-emitting type semiconductor light-emitting device according to the first embodiment in that the drive switch layer 28 is inserted below the active region 18. In other words, the current confinement structure at the center of the surface emitting laser structure layer is formed by selectively oxidizing the AlGaAs layer.
[0053]
As shown in FIG. 5, on an n-type conductive substrate (n-type GaAs substrate) 10, an n-type buffer layer (n-type GaAs buffer layer) 12, an n-type multilayer mirror layer 14, a drive switch layer 28, a second switch 1 spacer layer 16, active region 18, second spacer layer 20, Al_0.98Ga_0.02An As layer 50 (film thickness 65.4 nm) is grown in this order. On top of this, a p-type multilayer mirror layer 22 and a p-type contact layer 26 are stacked by MOCVD. The configuration of each layer and the carrier concentration are the same as those in the first embodiment. However, the drive switch layer 28 is composed of an n-type multilayer mirror layer in the first embodiment, but in the present embodiment, it is composed of a 1.5-cycle multilayer mirror layer whose conductivity type is changed to p-type. The spacer layer 16 is doped n-type (carrier concentration 5 × 10¹⁷/cm^Three) With this configuration, a semiconductor layer constituting an npn junction transistor is formed below the active region 18 by the spacer layer 16, the drive switch layer 28, and the n-type multilayer mirror layer 14.
[0054]
Next, using photolithography, etching is removed until the drive switch layer 28 is exposed on the surface to form a convex shape having a diameter of 50 μm as shown in FIG. Thereafter, the p-type GaAs contact layer 29 is regrown on the drive switch layer 28 by MOCVD again. This sample was heated to 400 ° C in a steam atmosphere and Al_0.98Ga_0.02Donut-shaped aluminum oxide Al with oxidized As layer 50 leaving a central part (diameter 5 μm)₂O_Three52 is formed. Aluminum oxide is highly insulating and does not conduct current._0.98Ga_0.02A current confinement structure in which current flows only in the central portion of the As layer 50 that is not oxidized is formed. As the electrodes, an n-type electrode 32 is formed on the n-type conductive substrate 10, a p-type electrode 34 is formed on the p-type contact layer 26, and a drive switch electrode 36 is formed on the p-type GaAs contact layer 29 on the drive switch layer 28. A surface-emitting type semiconductor laser having such a configuration can be driven by manipulating the potentials of the three electrodes 32, 34, and 36, or manipulating the current values flowing through these electrodes.
[0055]
Also in this embodiment, the same effect as in the first embodiment can be obtained.
Third embodiment
Next, a surface-emitting type semiconductor light-emitting element array according to a third embodiment of the present invention will be described with reference to FIGS. The surface-emitting type semiconductor light-emitting element array according to the third embodiment includes n-type surface-emitting laser elements shown in FIG. 1 arranged in a matrix, for example, in 12 rows × 1200 columns and provided on a conductive GaAs substrate 10. Each surface light emission is performed by applying a matrix voltage to the p-type electrode provided in the p-type contact layer and the drive switch electrode provided in the drive switch layer 28 and applying a predetermined voltage to these three electrodes. The type laser element is individually driven and controlled.
[0056]
FIG. 6 shows an outline of the manufacturing process of the surface-emitting type semiconductor light-emitting element array according to the third embodiment. 6 (1) to 6 (3), the upper diagram shows a plan view, and the lower diagram shows a cross-sectional view. A surface-emitting laser structure layer that is exactly the same as the surface-emitting laser element that is the surface-emitting semiconductor light-emitting element according to the first embodiment shown in FIG. 1 is laminated on the conductive GaAs substrate 10 by MOCVD. (FIG. 6 (1)). Here, as shown in FIG. 1, 14 is an n-type multilayer mirror, 22 and 24 are p-type multilayer mirrors, 26 is a p-type contact layer, and 28 is a drive switch layer.
[0057]
Next, protons are injected into a vertical and horizontal lattice pattern to form a proton injection region 40, and surface emitting laser elements (surface emitting semiconductor light emitting elements) are arranged in 12 rows × 1200 columns at a pitch of 42 μm in both the vertical and horizontal directions. A surface emitting semiconductor light emitting element array is formed (FIG. 6B). Next, as in the first embodiment (see FIG. 1), the p-type contact layer 26 and a part of the p-type multilayer mirror layer 24 of each surface-emitting laser element are removed by etching to drive n-type driving. The switch layer 28 is exposed. An n-type drive switch contact layer 30 is regrown thereon. The p-type electrode 34, the drive switch electrode 36, and the n-type electrode 32 are formed on the back surface of the p-type contact layer 26, the n-type drive switch contact layer 30, and the n-type GaAs substrate 10 as in the first embodiment. To do. A drive switch wiring 60 in the row direction is formed for the drive switch electrode 36, and a Si film having a thickness of 0.2 μm is formed on the wiring._ThreeN_FourA film 62 is deposited, and an anode wiring 64 perpendicular to the film 62 is formed so as to be connected to the p-type electrode 22 (FIG. 6 (3). FIG. 6 shows a laser array of 12 rows × 1200 columns so that the sectional view can be easily understood. Was rotated 90 °). Here, the laser array of 12 rows × 1200 columns was divided into four parts vertically and horizontally, and each 6 × 600 laser array was made into one block, and a matrix wiring of drive switch wiring 60 and anode wiring 64 was formed. Since the n-type electrode 32 is a common electrode, it is formed on the entire back surface of the GaAs substrate 10.
In this way, a laser array of 12 rows × 1200 columns composed of a 6-row × 600-column laser array wired in a matrix was formed.
[0058]
According to the surface emitting semiconductor light emitting element array according to the third embodiment, since the matrix wiring can be formed on the substrate surface having almost no unevenness, the matrix wiring is easy and the density of the matrix wiring is increased. Therefore, high-density integration of the surface-emitting type semiconductor light-emitting element can be achieved.
[0059]
In addition, since a conductive (Si-doped) GaAs substrate can be used as the substrate for crystal growth of the laser structure layer, there are few defects and the yield can be improved. Surface emitting semiconductor light emitting elements can be formed with high density and the yield can be increased, so that the cost can be reduced.
[0060]
Furthermore, in the conventional simple matrix wiring laser array, if the number of lasers connected to the wiring is large, the charge / discharge current to the wiring parasitic capacitance is large and the power consumption is large, and the wiring parasitic capacitance However, the present invention has solved all of these problems. That is, since the voltage change at each electrode during driving is small, the power consumption due to the parasitic capacitance of the wiring is reduced, and at the same time, a pulse current with good rectangularity can flow into the laser active region.
Furthermore, polyimide, silicon oxide film, silicon nitride film, etc. are used for the matrix wiring of conventional surface emitting lasers to embed deep irregularities, but the residual stress caused by this reduces the reliability of the laser. On the other hand, when the present invention is used, since the surface irregularities are shallow and the buried layer is thin, there is an effect that a problem such as a decrease in reliability due to residual stress does not occur.
[0061]
Next, pulse operation characteristics of the laser array 70 in which the laser elements are arranged in 12 rows × 1200 columns and an image forming apparatus using the laser array 70 as a light source will be described.
[0062]
Since the laser array 70 in which the laser elements are arranged in 12 rows × 1200 columns is an assembly of the laser arrays in which the laser elements are arranged in four 6 rows × 600 columns, the laser array in which the laser elements are arranged in 6 rows × 600 columns. The pulse operation will be described with reference to the drive sequence in FIG. Here, it is assumed that the electrode potential shown in FIG. 3 is driven with a setting shifted by −8.5 V as a whole. That is, the cathode electrode, which is a common electrode of the laser array 70, is set to −8.5V, and the potentials of the matrix wiring interconnected anode wiring 64 and drive switch wiring 60 are set to 0V. A pulse voltage of −0.5 V is applied to the drive switch wiring 60 of the laser row to be driven, and a pulse voltage of +1.5 V is applied to the anode wiring 64 of the laser to be emitted next, thereby causing a desired laser element to emit light. Assuming that the arrangement position of the x rows and y columns of the laser elements in the laser array is indicated by (x, y), the simulation for driving the laser elements having the arrangement position (6,600) was performed by the above method. The result is shown in FIG. A rectangular current flows in the active region of the laser element with the array position (6,600), but no current flows in the active region of the laser element with the array position (3,600) that is not driven. It was confirmed that only the desired laser element can be driven.
[0063]
An example of a method for driving the entire laser array 70 is shown in the time chart of FIG. First, a pulse voltage of −0.5 V and a pulse width of 1.2 μs is applied to the drive switch wiring 60-1 in the first row, and the potentials of the drive switch wirings 60-2 to 60-12 in the second to twelfth rows are set to 0. Set to. Next, a pulse voltage of +1.5 V and a pulse width of 1.0 μs is applied only to the anode wiring 64-i (i is an integer of 1 to 1200) of the i-th row laser to be emitted. Only the laser element at the intersection of the potential of the drive switch wiring of −0.5 V and the potential of the anode wiring 64-i of +1.5 V satisfies the driving conditions shown in FIG. That is, only a desired laser in the first row can be emitted. Next, after the potential of the drive switch wiring 60-1 becomes 0 V, a pulse voltage of −0.5 V and a pulse width of 1.2 μs is applied to the drive switch wiring 60-2 in the second row. As in the case of the first row, when a pulse voltage of +1.5 V and a pulse width of 1.0 μs is applied only to the anode wiring 64-i of a desired laser element to emit light, only the desired laser element emits light.
[0064]
In this manner, desired laser elements in the third, fourth,..., Twelfth rows can be made to emit light sequentially.
[0065]
Next, an image forming apparatus using the laser array 70 as a light source will be described with reference to FIG. In the figure, the image forming apparatus has a laser array 70 as a light source, a lens system 72, a photosensitive drum 74, and a reflection mirror 76. In such a configuration, the laser light emitted from the laser array 70 as a light source is condensed and imaged by the lens system 72, and the light emission pattern of the laser array 70 is projected onto the surface of the photosensitive drum 74. In the present embodiment, a reflection mirror 76 is inserted in the optical path in order to reduce the distance from the arrangement position of the laser array 70 to the arrangement position of the photosensitive drum 74.
[0066]
Further, in the present embodiment, by projecting the laser array 70 slightly within the light emitting point array plane, the projected point array 12 × 1200 projected point array projected onto the surface of the photosensitive drum 74 can be obtained. , 14400 dot sequences arranged at equal intervals.
[0067]
Accordingly, an image having a resolution of 14400 spots can be formed on the width of the photosensitive drum by the rotation of the photosensitive drum 74. Although omitted in FIG. 10, the image forming apparatus includes a charging corotron, a developing device, a transfer corotron, a fixing device, and a cleaning device. For driving the laser array, a signal processor or a laser array driver is used.
Further, according to the image forming apparatus according to the present embodiment, since the surface-emitting type semiconductor light emitting element array integrated with high density is used as the light source, the pixel pitch can be reduced, and the drive sequence described above (FIG. By using 9), the laser array is caused to emit light sequentially, so that a high-resolution image can be formed.
[0068]
Fourth embodiment
A surface emitting semiconductor light emitting element array according to a fourth embodiment of the present invention will be described with reference to FIGS. The surface emitting semiconductor light emitting element array according to the present embodiment is an array of surface emitting semiconductor light emitting elements (selective oxidation type surface emitting laser elements) according to the second embodiment arranged in 12 rows × 1200 columns. It is.
[0069]
When fabricating a laser array, it is particularly preferable to insert the drive switch layer 28 near the surface of the p-type multilayer mirror layer 22 as described in the first embodiment (FIG. 1). As described in the embodiment (FIG. 5), it is more advantageous than inserting the drive switch layer 28 at the end of the n-type multilayer mirror layer 14. This is because it is easier to form the matrix wiring near the surface of the laser structure layer.
[0070]
Next, FIG. 11 shows an outline of the manufacturing process of the surface-emitting type semiconductor light-emitting element array 80 according to the present embodiment, and FIG. 12 shows the sectional structure of each surface-emitting type laser element. Each laser structure of the surface-emitting type semiconductor light-emitting element array is formed into a convex shape by etching each layer formed on the conductive n-type GaAs substrate 10 as shown in FIG. That is, as shown in FIG. 12, an n-type GaAs buffer layer 12, an n-type multilayer mirror layer 14, a spacer layer 16, an active region 18, a spacer layer 20,_0.98Ga_0.02The As layer 50, the p-type multilayer mirror layer 22, the drive switch layer 28, the p-type multilayer mirror layer 24, and the p-type contact layer 26 are grown in this order. The drive switch layer 28 is exposed on the surface by etching, and the n-type drive switch contact layer 30 is regrown thereon. Next, the convex shape of the laser element is formed by etching.
[0071]
Next, as shown in FIG._0.98Ga_0.02Oxidized As layer 50, donut-shaped aluminum oxide Al₂O_Three52 is produced.
[0072]
Further, the surface of the convex laser array is filled with polyimide 84 and flattened by etching (FIG. 11 (3)). Then, a drive switch wiring 86 is formed, and an insulating film Si is formed to cover this._ThreeN_Four88 is formed. A p-type electrode wiring 90 is formed in the vertical direction of the drive switch wiring 86 and a matrix wiring is laid. A common electrode 92 is formed on the back surface of the n-type GaAs substrate 10 (FIG. 11 (4)).
[0073]
In this manner, by applying a predetermined voltage to the three electrodes (or wirings) 86, 90, and 92 formed, the laser array 80 in which the laser elements are arranged in 12 rows × 1200 columns can be driven. The driving method is the same as that of the third embodiment, so that it can be used as a light source of the image forming apparatus. Although this image forming apparatus is an electrophotographic system, it goes without saying that it can also be used as a light source for direct printing, which is another printing system.
[0074]
Fifth embodiment
An image display apparatus according to the fifth embodiment of the present invention will be described. Prior to the description of the image display device, an AlGaInP laser array in which laser elements emitting red light having a wavelength of 650 nm used as a light source of the image display device are arranged in 12 rows × 120 columns will be described.
[0075]
The laser structure layer of each surface-emitting type laser element constituting this laser array is formed with a spacer layer and an active region of an AlGaInP-based material so as to emit red light (wavelength 680 nm) as its output light, and a multilayer mirror layer Was made of AlGaAs-based material. Specifically, the structure is such that an n-type GaAs buffer layer, n-type AlAs / Al on a conductive n-type GaAs substrate._0.5Ga_0.5As multilayer mirror layer, non-doped AlInP spacer layer, GaInP / AlGaInP triple quantum well active region, non-doped AlInP spacer layer, p-type AlAs / Al_0.5Ga_0.5As multilayer mirror layer, n-type Al_0.5Ga_0.5As / AlAs / Al_0.5Ga_0.5As drive switch layer, p-type AlAs / Al_0.5Ga_0.5As A structure in which a multilayer mirror layer and a p-type GaAs contact layer are laminated in this order. This laser structure layer has a structure similar to that shown in FIG.
Thickness t of each layer of the multilayer mirror layer in the laser structure layer_iIs t for light of the laser wavelength λ (here 780 nm)_i= Λ / (4 ・ n_i) (N)_iIs the refractive index of each layer), and high reflectivity is achieved. In addition, each layer of the spacer layer and the active region has a thickness t of each layer._iIs its refractive index n_iValue t multiplied by_i× n_iIs set to be equal to λ, and serves as a laser resonator.
[0076]
Similar to the laser array according to the third embodiment, a laser array in which laser elements are arranged in 12 rows × 120 columns by proton injection is fabricated on the substrate having such a laser structure layer. Further, as in the third embodiment, a common electrode is formed on the back surface of the GaAs substrate, and matrix wiring is laid on the p-type electrode and the drive switch electrode, so that the potential and current of these three electrodes are increased. Is operated, the laser array 100 of 12 rows × 120 columns can be driven.
[0077]
FIG. 13 shows a configuration of an image display apparatus using the laser array 100 as a light source. In the figure, the image display apparatus includes a laser array 100 as a light source, lens systems 102 and 104, reflection mirrors 106 and 108, a polygon mirror 110, and a screen 112.
[0078]
In the above configuration, the laser light 114 emitted from the laser array 100 of 12 rows × 120 columns is temporarily imaged on the mirror surface of the polygon mirror 110 by the lens system 102 and the reflection mirror 106. Next, the light reflected by the polygon mirror 110 is projected from the back surface onto the image display screen 112 by the lens system 104 and the reflection mirror 108. Here, the light emitting point array projected on the screen 112 is slightly tilted so that the projected point arrays in the main scanning direction (horizontal direction) of the light emitting point array are arranged at equal intervals. Thereby, the resolution in the main scanning direction is 1440 spots, and the image display apparatus can display a high-definition image.
[0079]
If the polygon mirror 110 has three surfaces and the rotation speed is 10 rotations / second (600 rotations / minute), a moving image of 30 frames / second can be formed. The vertical resolution on the screen 112 can be easily realized by 1200 spots or more by using the driving sequence described in the third embodiment.
[0080]
In this embodiment, only the red laser array is used, so that only red display is possible. Needless to say, full-color display can be achieved by using the blue and green laser arrays.
[0081]
【The invention's effect】
As described above, according to the surface-emitting type semiconductor light-emitting device of the present invention, the third layer mirror layer (reflective layer) on the surface side constituting the surface-emitting type laser device is provided inside or below the third mirror layer. By inserting a multi-layer mirror layer (drive switch layer) having a different conductivity type, a switching element, for example, a pnp junction or npn junction semiconductor layer constituting a transistor is formed on the surface side constituting the surface emitting laser. In addition, an electrode is formed on the conductive substrate, the multilayer mirror tank on the surface side, and the drive switch layer, and the surface emitting laser is driven by operating the potential or current value of these three electrodes. Since the drive switch layer is formed so as to maintain the periodicity of the arrangement of the multilayer mirror layers on the surface side, the multilayer mirror as a reflection layer even if the drive switch layer is inserted Without reflectance is lowered, thereby improving the output characteristics of the surface-emitting laser as compared with the conventional.
[0082]
According to the surface emitting semiconductor light emitting element array according to the present invention, the common electrode is formed on the conductive substrate among the electrodes in each surface emitting semiconductor light emitting element, and the multilayer mirror layer and the drive switch layer on the surface side are formed. Since the matrix wiring is formed, there are few surface irregularities, the matrix wiring can be easily formed, and the laser element can be highly integrated.
[0083]
In the image forming apparatus according to the present invention, the surface-emitting type semiconductor light emitting element array according to the present invention which is integrated with high density is used as a light source, so that the pixel pitch can be made fine and a high-resolution image can be formed. it can.
[0084]
In the image display device according to the present invention, since the surface-emitting type semiconductor light-emitting element array according to the present invention that is integrated at a high density is used as a light source, the pixel pitch can be reduced, so that a high-resolution image can be displayed. Can do.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a cross-sectional structure of a surface-emitting semiconductor light-emitting device according to a first embodiment of the present invention.
FIG. 2 is an energy band structure diagram showing the operation principle of the surface-emitting type semiconductor light emitting device according to the first embodiment of the present invention.
3 is a circuit diagram showing an equivalent circuit of the surface-emitting type semiconductor light emitting element shown in FIG.
4 is a voltage-current characteristic diagram showing a relationship between a drive switch electrode potential and a current flowing through each part in the surface-emitting type semiconductor light-emitting device shown in FIG. 1;
FIG. 5 is a cross-sectional view showing a cross-sectional structure of a surface-emitting semiconductor light-emitting element according to a second embodiment of the present invention.
FIG. 6 is a process diagram showing a manufacturing process of a surface-emitting type semiconductor light-emitting element array according to a third embodiment of the present invention.
FIG. 7 is an explanatory diagram showing a driving sequence of a surface emitting semiconductor light emitting element array according to a third embodiment of the present invention.
FIG. 8 is a pulse current waveform diagram showing a driving simulation result of the surface emitting semiconductor light emitting element array according to the third embodiment of the present invention.
FIG. 9 is a timing chart showing a driving sequence when driving the entire surface emitting semiconductor light emitting element array according to the third embodiment of the present invention.
FIG. 10 is a configuration diagram showing a schematic configuration of an image forming apparatus using a surface emitting semiconductor light emitting element array according to a third embodiment of the present invention as a light source.
FIG. 11 is a process diagram showing a manufacturing process of a surface emitting semiconductor light emitting element array according to a fourth embodiment of the present invention.
FIG. 12 is a cross-sectional view showing a cross-sectional structure of each surface emitting laser element of a surface emitting semiconductor light emitting element array according to a fourth embodiment of the present invention.
FIG. 13 is a configuration diagram showing a schematic configuration of an image display apparatus according to a fifth embodiment of the present invention.
FIG. 14 is a sectional view showing a part of a sectional structure of a conventional surface emitting laser array.
FIG. 15 is a cross-sectional view showing a cross-sectional structure of a surface emitting laser laser array equipped with a conventional transistor.
[Explanation of symbols]
10 n-type GaAs substrate
12 n-type GaAs buffer layer
14 n-type multilayer mirror layer (first multilayer mirror layer)
16 Spacer layer (first spacer layer)
18 Active region
20 Spacer layer (second spacer layer)
22, 24 p-type multilayer mirror layer (second multilayer mirror layer)
26 p-type contact layer
28 Drive switch layer (third layer)
30 Drive switch contact layer
32 n-type electrode
34 p-type electrode
36 Drive switch electrode

Claims (8)

A surface-emitting type semiconductor in which a first multilayer mirror layer, a first spacer layer, an active region, a second spacer layer, and a second multilayer mirror layer are arranged in this order on a semiconductor substrate. In the light emitting element,
A switching element composed of the inserted layer and the third layer is inserted into the light emitting element by inserting a third layer having a conductivity type different from that of the layer inserted in any one of the layers excluding the active region. A surface-emitting type semiconductor light-emitting device characterized in that a semiconductor layer is formed. A first multilayer mirror layer, a first spacer layer, an active region, a second spacer layer, and a second multilayer mirror layer are arranged in this order on a semiconductor substrate. At least one of the mirror layer and the first spacer layer has the first conductivity type, and at least one of the second spacer layer and the second multilayer mirror layer has the second conductivity type opposite to the first conductivity type. In a surface emitting semiconductor light emitting device having a conductivity type,
A third layer of the second conductivity type is inserted into or at the end of the layer having the first conductivity type, or the first conductivity type is inserted into or at the end of the layer of the second conductivity type Forming a semiconductor layer constituting the switching element by inserting the third layer of
A first electrode formed in a layer having a first conductivity type below the third layer; and a second electrode formed in a layer having a second conductivity type above the third layer. A surface-emitting type characterized in that light emission can be controlled by driving an electrode and a third electrode formed on the third layer or a contact layer formed on the third layer. Semiconductor light emitting device. A first multilayer mirror layer, a first spacer layer, an active region, a second spacer layer, and a second multilayer mirror layer are arranged in this order on a conductive semiconductor substrate, The semiconductor substrate and the first multilayer mirror layer have the first conductivity type, and at least one of the second spacer layer and the second multilayer mirror layer is the second conductivity type opposite to the first conductivity type. In a surface emitting semiconductor light emitting device having a conductivity type,
A third layer of the second conductivity type having the second conductivity type is inserted into or inside the first multilayer mirror layer having the first conductivity type, or has the second conductivity type. A semiconductor layer constituting a switching element is formed by inserting a third layer of the first conductivity type into the inside or the end of the second multilayer mirror layer,
A first electrode formed on the conductive substrate; a second electrode formed on a second conductivity type layer above the third layer; and on the third layer or the third layer. A surface-emitting semiconductor light-emitting element configured to control light emission by driving a third electrode formed in a formed contact layer. Each of the first and second multilayer mirror layers has a thickness λ / (4 · n _i ) (λ is the wavelength of light emitted from the active layer, n _i is the refractive index of each layer) The first spacer layer, the second spacer layer, and the active region have a laminated structure, and the total of the values t _i · n _{i obtained} by multiplying the thickness t _i of each layer by the refractive index n _i of each layer is λ Configured to be equal,
4. The surface-emitting type according to claim 1, wherein the third layer is formed so as to maintain the above-described configuration of the layer in which the third layer is inserted. 5. Semiconductor light emitting device. The third layer is a first multilayer mirror layer or a multilayer mirror layer inserted into the second multilayer mirror layer or at the end thereof, and the third layer is a multilayer mirror layer in which the third layer is inserted The surface-emitting type semiconductor light-emitting device according to claim 4, wherein the surface-emitting type semiconductor light-emitting device is formed so as to maintain the periodicity of the structure. A surface-emitting type semiconductor light emitting device according to any one of claims 2 to 5 is two-dimensionally arranged, and either one of the first electrode and the second electrode is used as a common electrode, A matrix wiring is formed for the other electrode of the first electrode or the second electrode and the third electrode, and each of the surface emitting semiconductor light emitting elements can be driven by these three electrodes. A surface-emitting type semiconductor light-emitting element array. An image forming apparatus using the surface-emitting type semiconductor element array according to claim 6 as a light source and printing an image using light emitted from the light source. An image characterized in that the surface-emitting type semiconductor light-emitting element array according to claim 6 is used as a light source, and light emitted from the light source is irradiated onto a display surface using an optical system to display a still image or a moving image. Display device.

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