JP2004342885A - Light emitting element and light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make preventable breakdown of elements by the static electricity without increase in occupation space and mounting processes. <P>SOLUTION: The light emitting device 1 includes, on a substrate 2, a semiconductor light emitting element K comprising an n-type semiconductor layer 3, an active layer 4, a p-type semiconductor layer 5, and an anode electrode film. A thin film capacitor 8 formed by laminating an insulation film 9 and an electrode film 10 is formed on the anode electrode 6, and the electrode film 10 is connected with the n-type semiconductor layer 3. Consequently, electrostatic breakdown of the semiconductor light emitting device 1 can be prevented through electrically parallel connection of the thin film capacitor 8 and semiconductor light emitting element K. Since the thin film capacitor 8 is formed on the same substrate together closely with the semiconductor light emitting device 1, reduction in size and lower cost may be realized. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-216442 [Patent Document 2]
Japanese Patent Application Laid-Open No. 2001-230448 [Patent Document 3]
JP-A-2002-94121
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a light emitting element using a semiconductor film formed on a substrate and a light emitting device using the light emitting element.
[0003]
[Prior art]
In recent years, light-emitting elements using gallium nitride-based materials have been incorporated as light sources for blue, green, or white light-emitting devices, and have been commercialized. This type of light emitting device includes a sapphire substrate or the like having a light emitting function portion (hereinafter, referred to as “semiconductor light emitting device” in the present specification) including a semiconductor film using a gallium nitride-based compound semiconductor, an anode electrode, and a cathode electrode. A light emitting device is manufactured by incorporating an LED chip (hereinafter, referred to as "light emitting element" in the present specification) having a semiconductor light emitting element formed on an insulating substrate into an appropriate case. are doing.
[0004]
When the light emitting device configured as described above is actually used, conventionally, when a high voltage is applied between both electrodes due to static electricity due to high insulation between the anode electrode and the cathode electrode, the internal There is a problem that the light emitting element is destroyed (electrostatic breakdown, ESD).
[0005]
Conventionally, in order to solve this problem, electronic components such as resistors, capacitors, and varistors are mounted on an electric circuit board outside a light emitting device (LED lamp) to prevent electrostatic breakdown of a semiconductor light emitting element inside the light emitting device. A configuration in which a diode is connected in parallel with the semiconductor light emitting element inside the light emitting device (for example, see Patent Documents 1 and 2), or a configuration in which a resistor is connected inside the light emitting device (for example, Patent Document 3) has been proposed.
[0006]
[Problems to be solved by the invention]
However, according to the configuration in which the electronic components are mounted outside the light emitting device, the number of components to be mounted on the circuit board increases, and the size of the circuit board increases due to the occupied space. However, since the number of steps increases, there is a problem that the cost of the apparatus is increased and the size is increased. In addition, according to the configuration in which components for preventing electrostatic breakdown are incorporated in the light emitting device, since a resistor or a capacitor having an extremely small dimension is mounted inside the device, the process becomes complicated, and the cost is increased. Have a point. In any case, since the individual electronic components are attached to the light emitting element, the manufacturing cost must be increased due to the attachment.
[0007]
An object of the present invention is to provide a light-emitting element and a light-emitting device with high electrostatic breakdown resistance, which can solve the above-described problems in the related art.
[0008]
An object of the present invention is to use a light emitting element and a light emitting element capable of preventing the destruction of the element due to static electricity without increasing the occupied space and the mounting process by adding additional components. To provide a light emitting device.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a light-emitting element in which a semiconductor light-emitting element formed using a compound semiconductor film is formed on a substrate, wherein the film-shaped anode electrode or the film-shaped cathode is provided on the semiconductor light-emitting element. A thin-film capacitor using electrodes is provided so that the thin-film capacitor and the semiconductor light-emitting element are electrically connected in parallel. Since the thin-film capacitor is electrically connected in parallel with the semiconductor light-emitting element, it is possible to prevent electrostatic breakdown of the semiconductor light-emitting element even if an abnormal high-voltage pulse caused by static electricity is applied to the semiconductor light-emitting element It becomes. Since this thin film capacitor is formed on the same substrate so as to be in close contact with the semiconductor light emitting element, it is possible to reduce the size and cost.
[0010]
According to the first aspect of the present invention, there is provided a light emitting device comprising a semiconductor light emitting device formed on a single crystal substrate, comprising a thin film capacitor having an insulating film formed on the substrate as a dielectric, There is proposed a light emitting device, wherein the device and the thin film capacitor are provided electrically in parallel.
[0011]
According to the invention of claim 2, in a light emitting device in which a semiconductor light emitting device is formed on a single crystal substrate, a thin film capacitor in which an insulating film and an electrode film are laminated on a thin film electrode of the semiconductor light emitting device A light emitting device is proposed, wherein the thin film capacitor is electrically connected in parallel with the semiconductor light emitting device.
[0012]
According to the invention of claim 3, an N-type semiconductor layer, an active layer formed on the N-type semiconductor layer, and a P-type semiconductor layer formed on the active layer are formed on a single-crystal substrate. And a film-shaped anode electrode formed on the P-type semiconductor layer.
A light-emitting element and a light-emitting device are provided, comprising a thin-film capacitor in which an insulating film and a transparent electrode film are laminated on the anode electrode, wherein the transparent electrode film is connected to the N-type semiconductor layer. You.
[0013]
According to the invention of claim 4, in the invention of claim 1, 2 or 3, wherein the insulating film, barium titanate, strontium _{titanate, SBT, BST, PZT, Ta} 2 O 5, Hf 2 O 5, Al There is proposed a light-emitting element that is a single-layer film or a stacked film selected from ₂ O ₃ , SiO ₂ , Si ₃ N ₄ , Y ₂ O ₃ , Gd ₂ O ₃ , TiO ₂ , ZrO ₂ , and La ₂ O _3. .
[0014]
According to a fifth aspect of the present invention, there is provided a light emitting device according to the first, second or third aspect, wherein the relative permittivity of the insulating film is 20 or more.
[0015]
According to a sixth aspect of the present invention, there is provided the light emitting device according to the first, second or third aspect, wherein the insulating film is a dielectric material having a cubic perovskite structure.
[0016]
According to the invention of claim 7, in the invention of claim 3, wherein the transparent conductive _{film, ITO, ATO, FTO, AZO} , In 2 O 3, SnO 2, ZnO, CdO, TiO 2, TiN, ZrN, HfN , Au, Ag, Pt, Cu, Pd, Al, and Cr are proposed.
[0017]
According to an eighth aspect of the present invention, in the third aspect, the anode electrode is made of an alloy material containing any one of Au, Ni, Pt, Ru, Ti, Pd, Mo, and Rh as a main component or A light emitting device that is a compound material is proposed.
[0018]
According to a ninth aspect of the present invention, in the invention of the first, second or third aspect, the semiconductor light emitting element has a mesa shape in which a sidewall taper angle with respect to a substrate surface of the substrate is 60 ° or less. Is proposed.
[0019]
According to the tenth aspect, in the first, second, or third aspect, the capacitance of the thin film capacitor is 50 pF or more, and the leakage current at a DC applied voltage of 4 V of the thin film capacitor is 1 × 10 A light emitting element having a current of ^-5 A or less is proposed.
[0020]
According to an eleventh aspect of the present invention, there is provided a light emitting device according to the first, second or third aspect, wherein the substrate is a sapphire substrate, and the semiconductor light emitting device is made of a group III nitride semiconductor. .
[0021]
According to a twelfth aspect of the present invention, there is provided a light emitting device incorporating any one of the first to eleventh light emitting elements as a light source.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.
[0023]
FIG. 1 is a sectional view showing an example of an embodiment of a light emitting device according to the present invention. The light-emitting device 1 is a device in which a semiconductor light-emitting device is formed on a single-crystal substrate 2. The semiconductor light-emitting device is formed by a required vapor phase growth method such as an organic metal thermal decomposition method (MOCVD method). It can be manufactured by laminating a compound semiconductor single crystal thin film layer, and other necessary insulating films, electrode films, and the like can be formed using known appropriate means.
[0024]
On the substrate 2, respective layers of an N-type semiconductor layer 3, an active layer 4, and a P-type semiconductor layer 5 are formed in this order. The semiconductor light emitting device K including these three layers is etched in a mesa shape. Here, a part of the N-type semiconductor layer 3 is a thinner electrode forming portion 3A, and a side wall portion adjacent to the electrode forming portion 3A is a tapered surface 3B having a side wall taper angle θ. . Here, the sidewall taper angle θ is the illustrated angle of the substrate 2 with respect to the substrate surface 2A. The tapered surface 3B extends not only to the N-type semiconductor layer 3 but also to the active layer 4 and the P-type semiconductor layer 5 formed thereon.
[0025]
On the P-type semiconductor layer 5, an anode electrode 6 for electrically connecting the P-type semiconductor layer 5 to an external circuit is formed. The anode electrode 6 is formed on the P-type semiconductor layer 5 in a thin film shape. On the other hand, on the electrode forming portion 3A of the N-type semiconductor layer 3, a cathode electrode 7 for electrically connecting the N-type semiconductor layer 3 to an external circuit is formed. The cathode electrode 7 is also formed as a thin film on the electrode forming portion 3A.
[0026]
The semiconductor light emitting device K configured as described above on the substrate 2 is applied from the N-type semiconductor layer 3 to the active layer 4 by applying a voltage between the anode electrode 6 and the cathode electrode 7 with a required polarity. Electrons are injected, holes are injected from the P-type semiconductor layer 5 into the active layer 4, and the electrons and holes are recombined in the active layer 4 to emit light.
[0027]
On the anode electrode 6, a thin film capacitor 8 having the anode electrode 6 as one electrode is formed. The thin film capacitor 8 is formed on the anode electrode 6, further forms a transparent conductive film 10 on the insulating film 9, and has an extremely small form in which the insulating film 9 is sandwiched between the conductive film 10 and the anode electrode 6. This is a thin capacitor, and the conductive film 10 is the other electrode of the thin film capacitor 8.
[0028]
The thin film capacitor 8 is provided for the purpose of effectively preventing the semiconductor light emitting element from being electrostatically damaged even when a high voltage is applied between the anode electrode 6 and the cathode electrode 7 by the action of static electricity. Things.
[0029]
In order to electrically connect the thin film capacitor 8 to the semiconductor light emitting device in parallel, the conductive film 10 extends along the tapered surface 3B to the cathode electrode 7, and the end 10A of the conductive film 10 is connected to the cathode electrode 7. And it is in a state of being electrically connected to. In the present embodiment, the insulating film 9 is formed so as to extend to the tapered surface 3B, and covers the end 6A of the anode electrode 6 and the tapered surface 3B. As a result, the conductive film 10 is kept in a required insulating state electrically with the active layer 4, the P-type semiconductor layer 5, and the anode electrode 6.
[0030]
Thus, the thin film capacitor 8 formed by laminating the anode electrode 6, the insulating film 9, and the conductive film 10 is electrically connected to the anode electrode 6 and the cathode electrode 7, and the thin film capacitor 8 and the semiconductor light emitting device Since K is connected in parallel, it is possible to effectively suppress the generation of a high voltage between the anode electrode and the cathode electrode due to static electricity, and to effectively prevent electrostatic breakdown of the semiconductor light emitting device K. Can be.
[0031]
Since the thin film capacitor 8 is formed on the substrate 2 as described above so as to be tightly integrated with the semiconductor light emitting element K by utilizing a semiconductor manufacturing process, the space occupied by the thin film capacitor 8 is extremely small. No component mounting process is required. For this reason, miniaturization is possible, and a mounting process of additional components is not required, so that a small-sized and low-cost light emitting element can be realized.
[0032]
The semiconductor light emitting device K formed on the substrate 2 can be configured using a crystalline semiconductor film made of a group III nitride semiconductor. In this case, the substrate 2 is preferably a sapphire substrate, a SiC substrate, or a Si substrate. Further, the N-type semiconductor layer 3 can be formed using GaN doped with Si, the active layer 4 can be formed using a quantum well structure of GaN and InGaN, and the P-type conductive layer 5 can be formed using GaN doped with Mg. Of course, the present invention is not limited to this configuration. For example, the present invention can be applied to a case where the substrate 2 is a GaAs substrate or an InP substrate, and a crystalline semiconductor film is formed of an InAlGaPAs-based semiconductor light emitting element on this substrate. Can be.
[0033]
Further, in the present invention, the P-type conductive layer is constituted by a P-type cladding layer / a lightly doped P-type layer / a highly-doped P-type layer (contact layer) (for example, disclosed in JP-A-2001-148507). Configuration). In this case, since the lightly doped P-type layer increases the series resistance of the LED element, the operating voltage of the LED is slightly increased, but the measures for preventing destruction due to static electricity are doubled, so that the LED element which is more resistant to static electricity. Can be
[0034]
The material of the anode electrode 6 and the material of the cathode electrode 7 may be selected so as to form an ohmic junction with the semiconductor film of each conductivity type. When the semiconductor film is a group III nitride semiconductor, a good ohmic junction can be obtained by using AuNi for the anode electrode and TiAl for the cathode electrode. In addition, the anode electrode can be formed using an alloy material or a compound material containing any one of Au, Ni, Pt, Ru, Ti, Pd, Mo, and Rh as a main component.
[0035]
The material of the insulating film 9 is compatible with the conditions that absorption at the emission wavelength is small, dielectric constant is high so that the capacitance can be as large as possible, and leak current during operation of the semiconductor light emitting element is as small as possible. Choose one. For example, barium titanate, strontium _{titanate, SBT, BST, PZT, Ta} 2 O 5, Hf 2 O 5, Al 2 O 3, SiO 2, Si 3 N 4, Y 2 O 3, Gd 2 O 3, TiO ₂ , ZrO ₂ , La ₂ O _{3 and the} like are suitable as the material of the insulating film 9. Here, the insulating film 9 can be a single-layer film or a laminated film selected from these materials. Further, the insulating film 9 is preferably made of a dielectric material having a cubic perovskite structure.
[0036]
Examples of the material of the transparent conductive film 10 include ITO, ATO, FTO, AZO, In ₂ O ₃ , SnO ₂ , ZnO, CdO, TiO ₂ , TiN, ZrN, HfN, Au, Ag, Pt, Cu, Pd, and Al. , Cr and the like are preferred. Here, the transparent conductive film 10 can be a single-layer film or a laminated film selected from these materials.
[0037]
FIG. 2 is a sectional view showing a modification of the embodiment of the present invention shown in FIG. 2 corresponding to those in FIG. 1 are denoted by the same reference numerals. In the light emitting element 20 shown in FIG. 2, a transparent conductive film 10 'constituting the other electrode of the thin film capacitor 8 is extended along the tapered surface 3B to the electrode forming portion 3A, and the end 10 A differs from the light emitting device 1 shown in FIG. 1 only in that 'A also serves as a cathode electrode used to connect the N-type semiconductor layer 3 to an external circuit.
[0038]
According to this configuration, it is not necessary to separately form the cathode electrode 7 and the transparent conductive film 10 in FIG. 1, and only the formation of the transparent conductive film 10 'is sufficient, so that the manufacturing process can be further simplified. it can.
[0039]
FIG. 3 is a cross-sectional view showing another embodiment of the present invention. 3 that are the same as those in FIG. 1 are denoted by the same reference numerals. The light emitting element 30 shown in FIG. 3 has a thin film capacitor 31 formed on the cathode electrode 7 in the same manner as the thin film capacitor 8 of FIG. That is, in the thin film capacitor 31, a transparent conductive film 33 is further formed on the insulating film 32 formed on the cathode electrode 7, and the insulating film 32 is sandwiched between the conductive film 33 and the cathode electrode 7. It is a thin film capacitor, in which the cathode electrode 7 is one electrode and the conductive film 33 is the other electrode.
[0040]
The insulating film 32 extends to the upper end 3Ba above the N-type semiconductor layer 3 along the tapered surface 3B. On the other hand, the transparent conductive film 33 also extends on the insulating film 32 along the tapered surface 3B along the tapered surface 3B, and further extends from the upper end 3Ba to the P-type semiconductor layer 5. Then, the end 33A of the conductive film 33 formed on the P-type semiconductor layer 5 functions as an anode electrode for electrically connecting the P-type semiconductor layer 5 to an external circuit.
[0041]
According to the light emitting element 30, since only the transparent conductive film 33 is formed on the P-type semiconductor layer 5, external luminous efficiency can be improved as compared with the configuration shown in FIGS. Further, since it is not necessary to form the anode electrode in a separate step, the number of steps can be simplified, which contributes to cost reduction. Further, since the thin film capacitor 31 is provided at the foot of the tapered surface 3B, the thickness of the entire light emitting element 30 can be reduced.
[0042]
In any of the above embodiments, the height difference between the foot and the top of the tapered surface 3B may be as high as 1 μm or more. In the case where an insulating film or a transparent conductive film is formed on a step portion having such a height difference by a vapor deposition method, a sputtering method, a CVD method, or the like, when the insulating film or the transparent conductive film is a thin film, the step is formed when the side wall taper angle θ is 60 ° or more. It may not be possible to completely cover. In that case, problems such as disconnection of the transparent conductive film at the foot or short-circuiting between the transparent conductive film and the semiconductor layer may occur. Therefore, it is desirable that the taper angle θ of the tapered surface 3B be 60 ° or less.
[0043]
Further, if the capacitances of the thin film capacitors 8 and 31 are too small, the effect of preventing electrostatic breakdown cannot be sufficiently exhibited. On the other hand, if the leakage current of the thin film capacitors 8 and 31 is too large, the power consumption of the light emitting element increases, which is not desirable. Therefore, it is desirable that the capacitance is 50 pF or more and the leakage current at a DC applied voltage of 4 V is 1 × 10 ⁻⁵ A or less.
[0044]
Next, the relationship between securing the capacity of the thin film capacitor configured as described above and dielectric breakdown of the insulating film will be described. As is well known, the capacitance C of a dielectric capacitor is
C = ε′ε ₀ (S / t)
ε ′: relative dielectric constant ε ₀ : dielectric constant in vacuum (8.85E-12F / m)
S: capacitor area t: dielectric film thickness (distance between electrodes)
It is expressed as For example, the light emitting portion area per chip of the GaN-based blue LED (substantially equal to the anode electrode area) is about 200 μm × 200 μm. Now, it is assumed that a capacitor having an area of 200 μm × 200 μm is required to have a design capacitance of 600 pF. If the area of the capacitor is increased, the capacitance simply increases, but the area occupied by the capacitor also increases, which is not desirable.
[0045]
FIG. 4 is a graph showing the relationship between the relative permittivity of the dielectric and the film thickness at which the capacitor becomes 600 pF. FIG. 5 is a graph showing the relationship between the dielectric film thickness and the electric field strength, showing the electric field strength at a DC voltage of 4V. The graph shown in FIG. 4 indicates that in order to increase the capacitance of the capacitor to 600 pF or more, the dielectric film thickness can be increased as the relative dielectric constant increases, and the dielectric film thickness needs to be decreased as the relative dielectric constant decreases. Is shown. Also, the graph shown in FIG. 5 shows that when the operating voltage of the LED of 4 V is applied between the electrodes of the capacitor, the electric field intensity is weaker as the dielectric film is thicker, and the electric field intensity is stronger as the dielectric film is thinner. ing. From these graphs, it can be seen that the higher the dielectric constant, the thicker the dielectric film thickness for achieving the design capacity, and the smaller the electric field intensity on the film thickness during LED operation.
[0046]
On the other hand, when the relative dielectric constant is 20 or less, the film thickness needs to be 118 ° or less to achieve 600 pF. Such a thin film has an electric field strength of 3.4 MV / cm or more. When such an electric field strength is applied for a long time, most of the insulating films cause dielectric breakdown. Also, the controllability of the film thickness becomes more difficult as the film becomes thinner. Therefore, in this case, it is preferable that the relative permittivity of the insulating layer be larger than 20.
[0047]
FIG. 6 is a cross-sectional view illustrating an example of an embodiment of a light emitting device configured using the light emitting element 1 illustrated in FIG. In the light emitting device 40, the light emitting element 1 shown in FIG. 1 is fixed on a pedestal portion 42 integrally formed on the inner end of the first lead frame 41. The second lead frame 43 is provided so as to be substantially parallel to the first lead frame 41, and the cathode electrode 7 of the light emitting element 1 is electrically connected to the pedestal part 42 by the first connection conductor 44. The anode electrode 6 serves as a second connection conductor 45 and is electrically connected to the second lead frame 43. The inner ends of the first lead frame 41 and the second lead frame 43 are sealed with a transparent thermosetting resin 46.
[0048]
Therefore, light emission is obtained in the light emitting element 1 by applying a voltage between the first lead frame 41 and the second lead frame 43, and light from the light emitting element 1 passes through the transparent thermosetting resin 46 to the outside. Will be released. Since the capacitor for preventing electrostatic destruction is incorporated in the light emitting element 1 in advance as a thin film capacitor as described above, there is no need to add external parts, and the assembling process is not complicated. Further, since the light emitting element 1 has a configuration in which a thin film capacitor is connected in parallel with the semiconductor light emitting element, it is not necessary to increase the driving voltage applied between the first lead frame 41 and the second lead frame 43, Driving is possible and power consumption is low.
[0049]
【Example】
Hereinafter, an example of the present invention will be described, but the present invention is not limited thereto.
[0050]
A light emitting device having the structure shown in FIG. 1 was manufactured as follows. A sapphire substrate is used as the substrate 2. On the sapphire substrate, Si-doped GaN is formed as an N-type semiconductor layer 3, a GaN＼InGaN multiple quantum well is formed as an active layer 4, and Mg-doped GaN is formed as a P-type semiconductor layer 5 by MOCVD. Then, a blue light emitting diode element was formed. On this blue light emitting diode element, a thin film capacitor using a barium titanate film formed by spin coating as a dielectric was formed, and the blue light emitting diode element and the thin film capacitor were electrically connected in parallel. The capacitance of the thin film capacitor was 260 pF.
[0051]
FIG. 7 is a circuit diagram for testing the resistance of the light emitting element to electrostatic discharge. Here, Vo is a variable DC power supply, Rp and R are resistors, C is a capacitor, and Sw is a changeover switch. The test was performed as follows. A machine model (R = 0Ω, C = 200 pF) condition for electrostatic discharge to the light emitting element 1 from an electrostatically charged device or jig was used. After setting the voltage of the variable DC power supply Vo in FIG. 7 to a certain value and switching the changeover switch Sw as shown by a solid line to charge the capacitor C via the resistor Rp, the changeover switch Sw is shown by a dotted line. And the light emitting element 1 is discharged. After repeating this three times, the voltage-current characteristics of the blue light emitting diode device were evaluated. A change in the voltage-current characteristics of the blue light emitting diode element makes it possible to determine whether the element has been destroyed.
[0052]
In the conventional blue light emitting diode device, 50% of the devices tested at 60 V failed. On the other hand, in the case of the embodiment in which the 260 pF thin film capacitor was connected in parallel with the blue light emitting diode element, 50% of the elements were destroyed at 150 V. That is, it was confirmed that the withstand voltage to electrostatic breakdown was improved by 90V.
[0053]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the destruction of the semiconductor light emitting element by static electricity is possible, and the light emitting element and the light emitting element can be used as a light source without increasing the occupied space and the mounting process by attaching additional components. A light emitting device incorporated as a light emitting device can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating an example of an embodiment of a light-emitting element according to the present invention.
FIG. 2 is a sectional view showing a modification of the embodiment shown in FIG. 1;
FIG. 3 is a sectional view showing another embodiment of the light emitting device according to the present invention.
FIG. 4 is a graph showing the relationship between the relative dielectric constant of a dielectric and the film thickness at which the capacitor becomes 600 pF.
FIG. 5 is a graph showing a relationship between a dielectric film thickness and an electric field intensity.
FIG. 6 is a cross-sectional view illustrating an example of an embodiment of a light emitting device according to the present invention.
FIG. 7 is a circuit diagram for testing resistance of a light emitting element to electrostatic discharge.
[Explanation of symbols]
1, 20, 30 Light-emitting element 2 Substrate 3 N-type semiconductor layer 3A Electrode forming portion 3B Tapered surface 4 Active layer 5 P-type semiconductor layer 6 Anode electrode 7 Cathode electrode 8 Thin film capacitor 9, 32 Insulating film 10, 33 Conducting film θ Side wall taper angle K Semiconductor light emitting device

Claims (12)

A light-emitting element formed by forming a semiconductor light-emitting element on a single-crystal substrate, comprising a thin-film capacitor having an insulating film formed on the substrate as a dielectric, wherein the semiconductor light-emitting element and the thin-film capacitor are electrically connected. A light-emitting element, which is provided in parallel to the light-emitting element. A light emitting device comprising a semiconductor light emitting device formed on a single crystal substrate, comprising a thin film capacitor comprising an insulating film and an electrode film laminated on a thin film electrode of the semiconductor light emitting device, wherein the thin film capacitor is A light-emitting element which is electrically connected in parallel with the light-emitting element. An N-type semiconductor layer, an active layer formed on the N-type semiconductor layer, a P-type semiconductor layer formed on the active layer, and a P-type semiconductor layer formed on the single-crystal substrate A light-emitting element formed by forming a semiconductor light-emitting element comprising a film-shaped anode electrode,
A light-emitting element and a light-emitting device, comprising: a thin-film capacitor having an insulating film and a transparent electrode film laminated on the anode electrode, wherein the transparent electrode film is connected to the N-type semiconductor layer. Wherein the insulating film is, barium titanate, strontium _{titanate, SBT, BST, PZT, Ta} 2 O 5, Hf 2 O 5, Al 2 O 3, SiO 2, Si 3 N 4, Y 2 O 3, Gd 2 O _{3, TiO 2, ZrO 2,} La 2 light emitting device according to claim 1, 2 or 3, wherein _{O 3} is a single layer film or a laminated film selected from. The light emitting device according to claim 1, 2 or 3, wherein a relative dielectric constant of the insulating film is 20 or more. 4. The light emitting device according to claim 1, wherein the insulating film is a dielectric material having a cubic perovskite structure. The transparent conductive film is selected from ITO, ATO, FTO, AZO, In ₂ O ₃ , SnO ₂ , ZnO, CdO, TiO ₂ , TiN, ZrN, HfN, Au, Ag, Pt, Cu, Pd, Al, and Cr. The light emitting device according to claim 3, wherein the light emitting device is a single layer film or a laminated film. The light emitting device according to claim 3, wherein the anode electrode is an alloy material or a compound material containing any one of Au, Ni, Pt, Ru, Ti, Pd, Mo, and Rh as a main component. 4. The light emitting device according to claim 1, wherein the semiconductor light emitting device has a mesa shape having a side wall taper angle of 60 ° or less with respect to a substrate surface of the substrate. 4. The light emitting device according to claim 1, wherein the capacitance of the thin film capacitor is 50 pF or more, and the leak current at a DC applied voltage of 4 V of the thin film capacitor is 1 × 10 ⁻⁵ A or less. 4. The light emitting device according to claim 1, wherein the substrate is a sapphire substrate, and the semiconductor light emitting device is made of a group III nitride semiconductor. A light-emitting device incorporating the light-emitting element according to any one of claims 1 to 11 as a light source.

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