KR20150004649A - Semiconductor device including transparent electrode and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a wafer level package for an image sensor and a manufacturing method thereof. The wafer level package for the image sensor according to the present invention includes a wafer which has one side and the other side which is separated from one side and includes a pad on one side, a cavity partition layer which is formed on the pad, and a cover glass substrate which is combined with the cavity partition layer. The cavity partition layer is formed on one side of the wafer by a photolithography method using a dry film.

Description

TECHNICAL FIELD [0001] The present invention relates to a semiconductor device including a transparent electrode, and a method of manufacturing the same. [0002]

The present invention relates to a semiconductor device including a transparent electrode and a manufacturing method thereof.

Transparent electrodes are used in various fields such as LED, solar cell, medical ultraviolet sterilizer, and fishery industry, and their application fields and their demand are increasing. In particular, transparent electrodes are widely used in the LED field, and current transparent electrode technology applied to LEDs can be applied to some regions (365 nm to 400 nm) of the visible light region (400 nm-800 nm) and the entire ultraviolet region (10 nm-400 nm) Based ITO (Indium Tin Oxide) based technology.

 In recent years, there is a rapid increase in demand for UV LEDs that emit light in the ultraviolet region. However, since transparent electrodes exhibiting high conductivity and high transmittance in the ultraviolet region have not been developed so far, ultraviolet LEDs are difficult to commercialize.

For example, in the case of a UV LED in which an ITO transparent electrode is most widely used at present, light of a short wavelength ultraviolet region (10 nm to 320 nm) generated in the active layer is mostly absorbed in ITO, Is only about 1%.

1 is a diagram showing transmittance in a conventional LED structure.

And the conventional ITO transparent electrode is formed on the P-GaN semiconductor layer.

As shown in the figure, the transmittance in the region having a wavelength of 350 nm or more is 80% or more, but the transmittance in the ultraviolet region in a short wavelength is drastically reduced. In particular, in the short wavelength region of 116 nm or less, the transmittance is reduced to 20% or less.

 Another conventional technique for solving this problem is to form a metal electrode pad directly without forming a transparent electrode on a semiconductor layer such as p-AlGaN. However, since the work function difference between the metal and the semiconductor layer is too large, There is a problem that contact is not made. Also, the current is concentrated on the metal electrode pads and is not supplied to the entire active layer, so that the amount of light generated in the active layer is significantly reduced.

In order to solve this problem, various studies have been carried out, but a transparent electrode showing high conductivity and high transmittance simultaneously in the ultraviolet region has not been developed yet. This is because the conductivity and permeability of the material have a trade-off relationship with each other. Since a material having a high transmittance to be used in the ultraviolet region has a large band gap, conductivity is very low to be used as an electrode, and an ohmic contact with a semiconductor material is not made, Do.

As an example of the proposed technique for solving such a problem, a technique of forming a transparent electrode into a thin film of silver (Ag) has been filed as Korean Patent Application No. 10-2007-0097545. However, in the case of forming a transparent electrode using silver (Ag) in such a conventional technique, it is very difficult to deposit thin silver (Ag) on the semiconductor layer so that ohmic contact is formed, Even in the case of thin deposition, as shown in the graph of FIG. 4, in the region where the wavelength of light is 420 nm or less, the transmittance sharply drops to 80% or less, and in the region where the wavelength of light is 380 nm or less The transmittance is reduced to 50% or less, and there is no difference in the transmittance between the conventional ITO electrode and the transmittance of the ultraviolet region is hardly expected to be substantially improved.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a semiconductor device including a transparent electrode which exhibits high transmittance and high conductivity not only in a visible light region but also in an ultraviolet region of a short wavelength, And a manufacturing method thereof.

The present invention also provides a light emitting device, an organic light emitting device, a light receiving device, and a method of manufacturing the same, which include an improved transparent electrode.

According to a first aspect of the present invention, there is provided a semiconductor device comprising: a semiconductor layer; and a transparent electrode having one surface contacted with the semiconductor layer, wherein the transparent electrode is made of a resistance change material And a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material.

According to a second aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: providing a semiconductor layer; Forming a transparent electrode on one surface of the semiconductor layer, wherein the forming of the transparent electrode includes forming a resistance change material layer so that the one surface of the resistance change material layer is in contact with the semiconductor layer, And forming a conductive filament by applying a voltage.

According to a third aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: providing a substrate; Forming a transparent electrode on the substrate; and contacting one surface of the transparent electrode with a semiconductor layer, wherein the forming of the transparent electrode comprises: forming a resistance change material layer on one surface of the substrate; And a forming step of forming a conductive filament by applying a voltage equal to or higher than a threshold voltage to the resistance change material layer.

A light emitting device according to a fourth aspect of the present invention includes a substrate, a first semiconductor layer formed on the substrate, an active layer formed on the first semiconductor layer, a second semiconductor layer formed on the active layer, And a second electrode pad formed on the upper portion of the transparent electrode, wherein the transparent electrode is made of a resistance change material, and the second electrode pad is formed on the upper portion of the transparent electrode, And has a conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance variable material.

A light emitting device according to a fifth aspect of the present invention includes a submount substrate, a reflective layer coupled with the submount substrate through a bonding layer, a transparent electrode coupled with the reflective layer, a second semiconductor layer coupled to the upper portion of the transparent electrode, A first semiconductor layer formed on the active layer, and an electrode pad formed on the first semiconductor layer, wherein the transparent electrode is made of a resistance change material, and the resistance And is conductive through the conductive filament formed by applying a voltage equal to or higher than the threshold voltage to the change material.

A light emitting device according to a sixth aspect of the present invention includes a submount substrate, a reflective layer coupled with the submount substrate through a bonding layer, a second semiconductor layer coupled with the reflective layer, A first semiconductor layer formed on the active layer, a transparent electrode formed on the first semiconductor layer, and an electrode pad formed on the transparent electrode, wherein the transparent electrode is made of a resistance change material, Through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage.

According to a seventh aspect of the present invention, there is provided a method of manufacturing a light emitting device, comprising: forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate; forming a transparent electrode on the second semiconductor layer; Exposing the first semiconductor layer by vertically etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode; And forming a first electrode pad in contact with an upper portion of the first semiconductor layer and a second electrode pad in contact with an upper portion of the transparent electrode, And a forming step of forming a conductive filament by applying a voltage equal to or higher than a threshold voltage to the resistance change material layer.

According to an eighth aspect of the present invention, there is provided a method of manufacturing a light emitting device, comprising: forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate; forming a transparent electrode on the second semiconductor layer; Forming a reflective layer on the transparent electrode; Exposing the first semiconductor layer by vertically etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode; Forming a first electrode pad in contact with an upper portion of the first semiconductor layer; providing a sub-mount substrate including a second electrode pad and a third electrode pad spaced apart from each other; Bonding the first electrode pad and the third electrode pad to each other through a bump, wherein the step of forming the transparent electrode includes forming a resistance change material layer so as to be in contact with the second semiconductor layer And a forming step of forming a conductive filament by applying a voltage equal to or higher than a threshold voltage to the resistance change material layer.

According to a ninth aspect of the present invention, there is provided a method of manufacturing a light emitting device, comprising: forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate; forming a transparent electrode on the second semiconductor layer; Forming a reflective layer on the transparent electrode; Forming a bonding layer on the reflective layer; Bonding the submount substrate to the bonding layer; Exposing the first semiconductor layer by removing the substrate; And forming an electrode pad on the first semiconductor layer, wherein the step of forming the transparent electrode includes the steps of: forming a resistance change material layer so as to be in contact with the second semiconductor layer; And a forming step of forming a conductive filament by applying a voltage equal to or higher than a threshold voltage.

According to a tenth aspect of the present invention, there is provided a method of manufacturing a light emitting device, comprising: forming a buffer layer on a substrate; Forming a resistance change material layer on one surface of the buffer layer; Forming a first semiconductor layer, an active layer, and a second semiconductor layer on the resistance change material layer; forming a reflective layer on the second semiconductor layer; Forming a bonding layer on the reflective layer; Bonding the submount substrate to the bonding layer; Exposing the resistance change material layer by removing the substrate; Forming a transparent electrode by performing a forming step on the resistance change material layer; And forming an electrode pad on the transparent electrode. The forming of the transparent electrode includes forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance change material layer.

An organic light emitting device according to an eleventh aspect of the present invention includes a substrate, a first electrode formed on the substrate, an organic material layer formed on the first electrode and including a light emitting layer, and a second electrode formed on the organic material layer, The second electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material.

According to a twelfth aspect of the present invention, there is provided an organic light emitting diode comprising a substrate, a first electrode formed on the substrate, the first electrode being a transparent electrode, an organic material layer formed on the first electrode and including a light emitting layer, Wherein the first electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material.

According to a thirteenth aspect of the present invention, there is provided a method of providing an organic light emitting diode, comprising: forming a first electrode on a substrate; forming an organic material layer including a light emitting layer on the first electrode; Wherein the step of forming the second electrode includes the steps of forming a resistance change material layer such that the resistance change material layer is in contact with the organic material layer and a voltage exceeding a threshold voltage is applied to the resistance change material layer, And a forming step of forming a film.

According to a fourteenth aspect of the present invention, there is provided a method of providing an organic light emitting diode, comprising: forming a first electrode as a transparent electrode on a substrate; forming an organic material layer including a light emitting layer on the first electrode; Wherein forming the first electrode includes forming a resistance change material layer such that the resistance change material layer is in contact with the substrate and a voltage higher than a threshold voltage is applied to the resistance change material layer, And forming a filament.

A light receiving element according to a fifteenth aspect of the present invention includes a photoelectric conversion layer, a transparent electrode which is in contact with one surface of the photoelectric conversion layer, and a counter electrode which is in contact with the other surface of the photoelectric conversion layer, And a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material.

A light receiving element according to a sixteenth aspect of the present invention includes a substrate, a first semiconductor layer formed on the substrate, an active layer formed on the first semiconductor layer, a second semiconductor layer formed on the active layer, A transparent electrode formed on the first semiconductor layer, a first electrode pad formed on the second semiconductor layer to be in contact with the first semiconductor layer, and a second electrode pad contacting the upper surface of the transparent electrode, And has a conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material.

According to a seventeenth aspect of the present invention, there is provided a method of manufacturing a light receiving element, comprising: forming a counter electrode on a substrate; A step of forming a photoelectric conversion layer on the counter electrode, and a step of forming a transparent electrode on the photoelectric conversion layer, the method comprising the steps of: forming a resistance change material layer so as to be in contact with the photoelectric conversion layer; And a forming step of forming a conductive filament by applying a voltage equal to or higher than a threshold voltage to the material layer.

According to an eighteenth aspect of the present invention, there is provided a method of manufacturing a light receiving element, including: forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate; forming a transparent electrode on the second semiconductor layer; Exposing the first semiconductor layer by vertically etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode; And forming a first electrode pad in contact with an upper portion of the first semiconductor layer and a second electrode pad in contact with an upper portion of the transparent electrode, And a forming step of forming a conductive filament by applying a voltage equal to or higher than a threshold voltage to the resistance change material layer.

A transparent electrode is formed of a transparent material whose resistance changes from a high resistance state to a low resistance state by an applied electric field. A voltage is applied to the transparent electrode to change the resistance state of the transparent electrode to a low resistance state The transparent electrode is made conductive so that the transparent electrode has a good ohmic characteristic with the semiconductor layer formed on the lower or upper side of the transparent electrode and has a high transmittance not only in the visible light region but also in the ultraviolet region of short wavelength Can be formed.

In addition, various types of semiconductor devices, light emitting devices, organic light emitting devices, and light receiving devices can be manufactured using such transparent electrodes.

1 is a diagram showing transmittance in a conventional LED structure.
2 is a view showing a structure of a semiconductor device according to an embodiment of the present invention.
3A to 3C are views for explaining the characteristics of the resistance change material.
4 is a view for explaining a method of forming a transparent electrode according to a preferred embodiment of the present invention.
5A and 5B are views showing a semiconductor device according to another embodiment of the present invention.
FIGS. 6A to 6E show the transmittance characteristics of the transparent electrode formed using the AlN material on the p-GaN semiconductor layer, the ohmic characteristics before the forming process, the contact resistance characteristics before the forming process, the ohmic characteristics after the forming process, And the contact resistance characteristics after the performance are shown, respectively.
FIGS. 7A to 7E show transmittance characteristics of a transparent electrode formed using a Ga 2 O 3 material on a p-GaN semiconductor layer, ohmic characteristics before a forming process, contact resistance characteristics before a forming process, ohmic characteristics after a forming process, And the contact resistance characteristics after the performance are shown, respectively.
FIGS. 8A to 8E are graphs showing transmittance characteristics of a transparent electrode formed using an AlN material on a p-Si semiconductor layer, ohmic characteristics before a forming process, contact resistance characteristics before a forming process, And the contact resistance characteristics after the performance
9 is a view illustrating a structure of a light emitting device having a transparent electrode according to a preferred embodiment of the present invention.
10 is a view for explaining a method of manufacturing a light emitting device according to a preferred embodiment of the present invention.
11A and 11B illustrate the structure of a light emitting device according to a preferred embodiment of the present invention for solving such a current concentration problem.
12A and 12B are diagrams showing a configuration of a light emitting device according to a preferred embodiment of the present invention.
13 is a view for explaining a method of manufacturing a light emitting device according to a preferred embodiment of the present invention.
14A and 14B are diagrams showing a structure of a light emitting device according to a preferred embodiment of the present invention.
15 is a view illustrating a method of manufacturing a light emitting device according to a preferred embodiment of the present invention.
16 is a view illustrating a structure of a vertical light emitting device having a transparent electrode according to a preferred embodiment of the present invention.
17 is a view illustrating a process of manufacturing a vertical light emitting device according to a preferred embodiment of the present invention.
18A and 18B show the structure of a light emitting device according to a preferred embodiment of the present invention.
19 is a view showing a structure of an organic light emitting diode according to a preferred embodiment of the present invention.
20 is a view for explaining a method of manufacturing an organic light emitting diode according to a preferred embodiment of the present invention.
21A and 21B are views illustrating a method of manufacturing an organic light emitting diode according to a preferred embodiment of the present invention.
22 is a view showing a structure of an organic light emitting device according to a preferred embodiment of the present invention.
23 is a view for explaining a method of manufacturing an organic light emitting diode according to a preferred embodiment of the present invention.
24A and 24B are diagrams showing a structure of an organic light emitting diode according to a preferred embodiment of the present invention.
25A to 25C are diagrams showing a configuration of a light receiving element according to a preferred embodiment of the present invention.
26 is a diagram showing an embodiment in which the light receiving element is implemented as a photodiode for ultraviolet rays according to a preferred embodiment of the present invention.
27 is a view for explaining a process of manufacturing a photodiode for ultraviolet rays according to a preferred embodiment of the present invention.
28A and 28B show a photodiode for an ultraviolet ray according to a preferred embodiment of the present invention.
29 is a diagram showing an example in which a light receiving element is implemented by a solar cell according to a preferred embodiment of the present invention.
30 is a view for explaining a process of manufacturing a solar cell having a transparent electrode 404 according to a preferred embodiment of the present invention.
31A and 31B are views showing a solar cell according to a preferred embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another part in between . Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

2 is a view showing a structure of a semiconductor device according to an embodiment of the present invention.

The illustrated semiconductor device includes a semiconductor layer 10 and a transparent electrode 20 having one surface in contact with the semiconductor layer 10. [ The transparent electrode 20 includes a conductive filament 22 formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. In addition, it includes a metal electrode pad 30 which is in contact with the other surface of the transparent electrode 20.

At this time, the semiconductor layer 10 includes not only the inorganic semiconductor layer and the organic semiconductor layer, but also all materials capable of flowing charges.

The inorganic semiconductor layer includes a single element semiconductor made of a single element such as Si and Ge. The inorganic semiconductor layer may be formed of a compound such as a nitride semiconductor compound semiconductor layer (GaN, AlGaN, InN, InGaN, AlN or the like) and an oxide semiconductor compound semiconductor layer (GaO, ZnO, CoO, IrO2, Rh2O3, Al2O3, A semiconductor layer. The inorganic semiconductor layer may typically include a material that constitutes an electron (hole) injection layer and an electron (hole) transport layer of an OLED (Organic Light Emitting Diode).

On the other hand, in order to improve the conductivity of the semiconductor layer 10, it is preferable that the surface of the semiconductor layer 10 which is in contact with the transparent electrode 20 is doped with p-type or n-type.

On the other hand, the transparent electrode 20 is made of a transparent resistance change material whose resistance state is changed by an applied electric field. The resistance change material is mainly used in the field of ReRAM (Resistive RAM). When a voltage higher than a specific threshold value is applied, electro-forming is performed so that the resistance state of the material, which is an insulator, To a low resistance state to exhibit conductivity.

3A to 3C are views for explaining the characteristics of the resistance change material.

3A, if a voltage equal to or higher than a threshold value is applied to the resistance change material, which is an insulator, electrode metal materials are inserted into the thin film by an electrical stress, Conducting filaments 22 (or metallic filaments) are formed in the resistance change material. Thereafter, when the voltage applied to the resistance-change material is removed, the conductive filament 22 is maintained, and current flows through the conductive filament 22, so that the resistance state of the material can be maintained in a low-resistance state.

Referring to FIG. 3B, it can be seen that the resistance variable material (AlN) exhibits the insulator characteristics before the forming process, and exhibits the I-V characteristics of the metal after the forming process. In addition, the conductive filament formed inside the transparent electrode may have a SET or RESET state as shown in FIG. 3B using a Joule-heating effect.

FIG. 3C is a graph showing how stable the conductive filament can be maintained after the conductive filament is formed. As shown by the red dotted line in the graph, it can be seen that a low resistance state can be maintained stably for 10 years after the conductive filament is formed .

In the preferred embodiment of the present invention, a transparent conductive oxide type material (SiO2, Ga2O3, Al2O3, ZnO, ITO, etc.), a transparent conductive nitride material (Si3N4, AlN, GaN, Transparent conductive nanomaterials such as CNT-oxide, Graphene, and Graphene-oxide were used as the transparent conductive polymer material (polyaniline (PANI), poly (ethylenedioxythiophene) -polystyrene sulfonate , It is a matter of course that the material can be used for forming the transparent electrode of the present invention as long as it is transparent and exhibits the above-described resistance change characteristics. However, the fact that the materials have conductivity means that they have conductivity by the foaming process.

4 is a view for explaining a method of forming a transparent electrode according to a preferred embodiment of the present invention.

First, a semiconductor layer 10 having the above-described characteristics is provided (step (a)), and then a transparent electrode 20 is formed on the semiconductor layer 10 (step (b)). At this time, the transparent electrode 20 can be formed by depositing the above-described resistance change material on the semiconductor layer 10.

Next, steps for forming a metal electrode for forming on the resistance change material layer constituting the transparent electrode 20 are sequentially performed (steps (c) to (f)). First, a photoresist layer (PR) 40 is formed on the resistance change material layer (step (c)), and a position for forming the electrode 32 for performing the forming using the mask 50 is exposed And a developing electrode pattern is formed on the photoresist layer 40 (step (d)). At this time, an electrode pattern is formed so that at least two electrodes are provided for applying a voltage. Next, a metal 34 is deposited on the patterned photoresist layer 40 to fill the pattern (step (e)), and a lift-off process is performed to form a pattern on the photoresist layer 40 The metal layer and the photoresist layer are removed to form the forming metal electrode 32 for performing the foaming process (step (f)). However, in this process, the metal electrode 32 for forming can be formed through various processes as an embodiment.

Next, when a voltage higher than a threshold voltage unique to the resistance change material layer is applied through the forming metal electrode 32, the conductive filament 22 is formed in the resistance change material layer, Is changed from the high resistance state to the low resistance state. At this time, the conductive filament 22 can proceed in a direction perpendicular to the resistance change material layer or in a horizontal direction.

Next, a metal electrode pad 30 is formed on the transparent electrode 20 (FIG. 4 (h)). For example, after the forming metal electrode 32 is removed, a step of forming the metal electrode pad 30 can be performed. Alternatively, the metal electrode pad 30 may be formed by further depositing a metal on the upper portion of the forming metal electrode 32. For this, the metal electrode pad 30 can be formed using the mask 52, as shown in FIG.

A semiconductor device including a transparent electrode according to a preferred embodiment of the present invention and a manufacturing method thereof have been described. The transparent electrode of the present invention is applied to all the transparent electrodes in contact with the semiconductor layer as described above, and various modifications are possible according to the semiconductor device to which the transparent electrode of the present invention is applied.

For example, in the above example, a transparent electrode is formed on a semiconductor layer. However, in the case of an OLED, a transparent electrode is formed on a glass substrate, a conductive filament is formed on the transparent electrode by performing a foaming process, Layer may be formed.

4, a transparent electrode layer is formed through a step of forming a resistance change material layer on a substrate, not a semiconductor layer, and a forming step, and then the substrate is removed to form a transparent electrode layer, The semiconductor device can be manufactured. According to this process, the process of forming the transparent electrode layer and the process of forming the semiconductor layer may be performed in separate processes, and then the semiconductor device may be manufactured in such a manner that the transparent electrode layer and the semiconductor layer are combined with each other.

On the other hand, in the embodiment described above with reference to FIGS. 2 and 4, it is possible that some of the conductive filaments 22 formed in the transparent electrode 20 are not connected to other conductive filaments 22. In this case, the current flowing into the transparent electrode 20 is locally concentrated without being diffused to the entire transparent electrode 20, so that the current is locally concentrated also in the semiconductor layer 10 contacting the transparent electrode 20 Problems may arise.

5A and 5B are views showing a semiconductor device according to another embodiment of the present invention.

5A and 5B, a configuration for improving the current spreading of the transparent electrode 20 is added to solve the current concentration problem. That is, a current diffusion layer 60 connecting the conductive filaments 22 formed on the transparent electrode 20 is formed on one surface of the transparent electrode 20. At this time, the current diffusion layer 60 may include a CNT (Carbon Nano Tube) layer or a graphene layer.

5A, the current diffusion layer 60 may be formed on the surface opposite to the surface where the transparent electrode 20 is in contact with the semiconductor layer 10. Alternatively, the current diffusion layer 60 may be formed between the transparent electrode layer 20 and the semiconductor layer 10 as shown in FIG. 5B.

 CNT or graphene is excellent in conductivity and light transmittance. In the present invention, a current diffusion layer 60 is formed on one side of the transparent electrode 20 using the above-mentioned characteristics to form the conductive filament 22 So that the current flowing into the transparent electrode 20 can be diffused to the entire region of the semiconductor layer 10.

In this case, as the current diffusion layer 60 is formed thicker, the CNTs or graphenes in the current diffusion layer 60 are mutually connected, and accordingly the conductive filaments 22 are more likely to be connected to each other, Is improved, but the transmittance is lowered. Therefore, it is preferable that the current diffusion layer 60 of the present invention is formed as thin as possible within a range that the conductive filaments 22 of the transparent electrode 20 are connected to each other, but the transmittance is not hindered.

In another preferred embodiment of the present invention shown in FIGS. 5A and 5B, a thickness of about 2 nm to about 100 nm is formed. 2 nm is the minimum thickness capable of forming CNT or graphene into a single layer, and 100 nm is the maximum thickness capable of maintaining the transmittance of light at 80% or more.

5A and 5B, except that the current diffusion layer 60 is formed immediately after the transparent electrode 20 is formed or immediately before the transparent electrode 20 is formed. 4, and thus a detailed description thereof will be omitted.

5A and 5B illustrate that the transparent electrode 10 is formed on the semiconductor layer 10, a semiconductor layer may be formed on the transparent electrode after the transparent electrode is formed. In this case, The current diffusion layer may be formed between the transparent electrode and the semiconductor layer, or may be formed on the opposite surface of the transparent electrode in contact with the semiconductor layer.

Hereinafter, light transmission characteristics and Ohmic characteristics of a transparent electrode according to a preferred embodiment of the present invention will be described with reference to FIGS. 6A to 8E. FIG.

FIGS. 6A to 6E show the transmittance characteristics of the transparent electrode formed using the AlN material on the p-GaN semiconductor layer, the ohmic characteristics before the forming process, the contact resistance characteristics before the forming process, the ohmic characteristics after the forming process, And the contact resistance characteristics after the performance are shown, respectively.

6A to 6E, a transparent electrode thin film (thickness: 80 nm) was formed of an AlN material having a large band gap of 6.1 eV on a p-GaN semiconductor layer frequently used in LEDs .

Referring to the graph shown in FIG. 6A, in the illustrated example, the transmittance is measured for light having a wavelength of 170 nm to 800 nm, the transmittance is measured only by quartz, and the result is shown as a reference line (black line) After the AlN transparent electrode was formed on the p-GaN semiconductor layer, the measurement result was shown by a red line. An AlN transparent electrode was formed on the p-GaN semiconductor layer and then heat treatment was performed at 138 degrees. Respectively.

As shown in the graph, the transparent electrode of the present invention shows a transmittance of 80% or more with respect to light in the ultraviolet region having a wavelength of 256 nm or more. It can be seen that the transmittance is remarkably improved as compared with the conventional ITO-based transparent electrode having the transmittance of 20% shown in FIG.

6B to 6E show the contact measured by the Ohmic characteristic (FIGS. 6B and 6D) and the TLM (Transfer Length Method) pattern when the distance between the measuring electrodes is 2 μm, 4 μm, 6 μm, 8 μm, Resistance characteristics (Figs. 6C and 6E).

Referring to FIG. 6B, when the distance between the measuring electrodes is 2 μm, the current value flowing through the transparent electrode is 0 to 6.0 * 10 ^-9 A , The current hardly flows, and the voltage-to-current relationship is not proportional. Also, referring to FIG. 6C, it can be seen that the ohmic contact resistance characteristic does not exhibit any linearity at all.

On the other hand, referring to Figure 6d, after the conductive filament is formed, relative to the case where the distance between the measuring electrode, 2㎛, when the 0V - 1.0V voltage applied to the transparent electrode, the transparent electrode from 0 to 5.0 * ^{10 As} the current flows about ³ A, 10 ⁶ times more current flows than before the foaming process, and the current-to-voltage relationship also shows a good ohmic characteristic proportional to each other. Referring to FIG. 6E, since the contact resistance characteristic also exhibits linearity, it can be seen that the ohmic contact resistance characteristic is significantly improved compared to before the foaming process.

The characteristics of the AlN transparent electrode formed on the p-GaN semiconductor layer of the example shown in FIGS. 6A to 6E are summarized as follows. The AlN transparent electrode exhibits a transmittance of 80% or more with respect to light in the ultraviolet region having a wavelength of 257 nm or more, Method) was measured by using the pattern, it represents the contact resistance of 24.113Ω㎝ ^-2 before performing the forming step, performed after the forming step exhibits a contact resistance of 1.33 * 10 ^-4 Ω㎝ ^-2 conductivity superior to Not only is improved, but also good ohmic characteristics are exhibited.

FIGS. 7A to 7E show transmittance characteristics of a transparent electrode formed using a Ga 2 O 3 material on a p-GaN semiconductor layer, ohmic characteristics before a forming process, contact resistance characteristics before a forming process, ohmic characteristics after a forming process, And the contact resistance characteristics after the performance are shown, respectively.

In the example shown in FIGS. 7A to 7E, a transparent electrode thin film (thickness: 80 nm) was formed of Ga 2 O 3 material on a p-GaN semiconductor layer widely used in LEDs.

Referring to the graph shown in FIG. 7A, it can be seen that the illustrated Ga 2 O 3 transparent electrode has a transmittance of 80% or more with respect to light in the ultraviolet region having a wavelength of 264 nm or more. It is also seen that the transmittance is remarkably improved as compared with the conventional ITO-based transparent electrode showing the transmittance of 20% shown in FIG.

7B to 7E are graphs showing the relationship between the distance between the measuring electrodes measured using the Ohmic characteristic (FIGS. 7B and 7D) and the TLM (Transfer Length Method) pattern when the distance between the measuring electrodes is 2 μm, 4 μm, 6 μm, 8 μm and 10 μm (Fig. 7C and Fig. 7E).

Referring to FIG. 7B, a current of about 1.0 * 10 < ^-11 > A flows through the transparent electrode irrespective of the voltage applied before the foaming process, based on the case where the distance between the measurement electrodes is 2 [ It does not show the ohmic characteristic. Also, referring to FIG. 7C, it can be seen that the ohmic contact resistance characteristic does not exhibit any linearity at all.

On the other hand, referring to FIG. 7D, when the distance between the measurement electrodes is 2 μm, the voltage applied to the transparent electrode is 0 V to 1.0 V after the forming process,

It can be seen that a current of 10 to ⁹ times more flows than before the foaming process and a current-to-voltage relationship is also proportional to each other, indicating good ohmic characteristics, since a current of about 0 to 2.0 * 10 ^-2 A flows. Also, referring to FIG. 7E, since the contact resistance characteristic also shows a linearity, it can be seen that the ohmic contact resistance characteristic is significantly improved compared to before the foaming process.

The Ga 2 O 3 transparent electrode formed on the p-GaN semiconductor layer of the example shown in FIGS. 7A to 7E is summarized as follows. The Ga 2 O 3 transparent electrode shows a transmittance of 80% or more for light in the ultraviolet region having a wavelength of 264 nm or more, As a result, the contact resistance was 51,150? Cm before the foaming process, but the contact resistance was 2.64 * 10 ^-5 ? Cm ^-2 after the foaming process, so that the conductivity was improved remarkably, Quot ;. < / RTI > FIGS. 8A to 8E show the transmittance characteristics of the transparent electrode formed on the p-Si semiconductor layer using the AlN material, the ohmic characteristics before the forming process, the contact resistance characteristics before the forming process, the ohmic characteristics after the forming process, And the contact resistance characteristics after the performance are shown, respectively.

In the example shown in Figs. 8A and 8B, a transparent electrode thin film (thickness: 80 nm) was formed of AlN material on the p-Si semiconductor layer.

Referring to the graph shown in FIG. 8A, it can be seen that the AlN transparent electrode of the present invention has a transmittance of 80% or more with respect to light in an ultraviolet ray region having a wavelength of 257 nm or more. It is also seen that the transmittance is remarkably improved as compared with the conventional ITO-based transparent electrode showing the transmittance of 20% shown in FIG.

8B to 8E illustrate the measurement of the distance between the measuring electrodes using the ohmic characteristics (FIGS. 8B and 8D) and the TLM (Transfer Length Method) pattern when the distance between the measuring electrodes is 2 μm, 4 μm, 6 μm, 8 μm, (Fig. 8C and Fig. 8E).

Referring to FIG. 8B, it can be seen that a current of about 0 to 0.5 * 10 ^-9 A flows through the transparent electrode irrespective of the voltage applied before the foaming process, based on the case where the distance between the measuring electrodes is 2 μm , And no ohmic characteristics are exhibited. Also, referring to FIG. 8C, it can be seen that the ohmic contact resistance characteristic does not exhibit any linearity at all. On the other hand, when the voltage applied to the transparent electrode is 0 V to 1.0 V, a current of about 0 to 8.0 * 10 ^-6 A flows through the transparent electrode after the foaming process is performed, 10 ³ times more current flows than before the foaming process, and the current-to-voltage relationship is not directly proportional to each other. However, it can be seen that the ohmic characteristics are better than those before the foaming process. Also, referring to FIG. 8E, the contact resistance characteristic also shows a linearity compared to that before the foaming process, and thus the ohmic contact resistance characteristic is significantly improved.

The characteristics of the AlN transparent electrode formed on the p-Si semiconductor layer of the example shown in FIGS. 8A to 8E are summarized as follows. The AlN transparent electrode shows a transmittance of 80% or more with respect to light in the ultraviolet region having a wavelength of 257 nm or more, and as a result, the forming step conducted after before performing represents the contact resistance of 20,816Ω㎝ ^-2, forming step measurement is 9.21 * ^10-4 exhibits a contact resistance of Ω㎝ ^-2 as well as improving the conductivity is superior, It can be seen that it exhibits good ohmic characteristics.

6A to 8E, the transparent electrode according to the preferred embodiment of the present invention has significantly improved transmittance and ohmic characteristics compared to the related art.

Table 1 below shows the transmittance and contact resistance characteristics of the transparent electrode used in the prior art together with ITO, and Table 2 shows the transmittance and contact resistance characteristics of the transparent electrode according to the preferred embodiment of the present invention.

As can be seen from Tables 1 and 2, the transparent electrode of the present invention exhibits significantly improved transmittance and contact resistance characteristics as compared with the transparent electrode of the related art.

9 is a view illustrating a structure of a light emitting device having a transparent electrode according to a preferred embodiment of the present invention.

9, a light emitting device includes a buffer layer 102, a first semiconductor layer 104, an active layer 106, and a second semiconductor layer 108 sequentially formed on a substrate 100, A transparent electrode 110 is formed on the layer 108 and electrode pads 114a and 114b are formed on the upper portion of the transparent electrode 110 and on the first semiconductor layer 104 where a part of the region is exposed .

The substrate 100 may be a substrate generally used for forming a light emitting device such as a sapphire substrate and a buffer layer 102 may be formed on the undoped GaN layer 104 to allow easy growth of the first semiconductor layer 104 Un-doped GaN), and may be omitted if necessary.

The first semiconductor layer 104 is an n-type doped semiconductor layer. In the preferred embodiment of the present invention, the first semiconductor layer 104 is formed of n-AlGaN to emit light in the ultraviolet region. However, Or may be formed of a general material used for manufacturing the device.

The active layer 106 (MQW) is preferably formed of Al (In) GaN / (In) GaN so that light in the ultraviolet region can be generated, but the material is not limited as long as it can emit light in the ultraviolet region .

The second semiconductor layer 108 is a p-type doped semiconductor layer. In a preferred embodiment of the present invention, a p-AlGaN single layer may be formed to emit light in the ultraviolet region, or a p-AlGaN Layer and a p-GaN thin film sequentially, but may be formed of a general material used for manufacturing a light emitting device capable of generating light in the ultraviolet ray region.

In the above-described embodiments, the first semiconductor layer 104 and the second semiconductor layer 108 are respectively doped with n-type and p-type semiconductor layers, but vice versa.

Meanwhile, the transparent electrode 110 of the present invention is formed of a transparent material (resistance change material) having a high transmittance to light including an ultraviolet ray region and a resistance state changed by an applied electric field. The resistance change material is mainly used in the field of ReRAM (Resistive RAM). When a voltage higher than a threshold value inherent to a material is applied to a material, electron-forming is performed so that the resistance state of the material, which is an insulator, Resistance state and exhibits conductivity.

Specifically, when a voltage equal to or higher than a threshold value is applied to the resistance change material, which is an insulator, an electrode metal material is inserted into the thin film by an electrical forming process, or the conductive filament 112: conducting filaments (or metallic filaments) are formed. Thereafter, when the voltage applied to the material is removed, the conductive filament 112 is maintained, and current flows through the conductive filament 112, so that the resistance state of the material is maintained in a low resistance state.

When the light emitting device is completed, currents injected through the electrode pads 114a and 114b formed on the transparent electrode layer 110 pass through the conductive filament 112 connected to each other in the transparent electrode 110, And the light generated in the active layer 106, especially light in the ultraviolet region, is emitted to the outside through the transparent electrode 110 having a large bandgap.

10 is a view for explaining a method of manufacturing a light emitting device according to a preferred embodiment of the present invention.

A buffer layer 102, a first semiconductor layer 104, an active layer 106 and a second semiconductor layer 108 are formed on a substrate 100 and a resistance change material layer 110 is formed on a second semiconductor layer 108 ).

4, a foaming step of forming a foaming electrode pattern in the resistance change material layer 110 and applying a voltage not lower than a threshold voltage is performed (b, c, d).

That is, a lithography process is performed to form a pattern for forming the forming electrode 118 in a part of the region of the photoresist 116 where the metal pad 114a is to be formed (b), and an electron beam (ebeam), a sputter The foaming electrode 118 is formed in the pattern by performing another metal deposition process and then the photoresist layer 116 excluding the foaming electrode 118 is removed through a lift-off process to form the forming electrode 118 ) (C). Next, as shown in (d), when a voltage higher than a threshold voltage that is inherent to the material is applied through the forming electrode 118 formed on the transparent electrode 110, the transparent filament 110, which is an insulating material, The resistance state of the transparent electrode 110 is changed from the high resistance state to the low resistance state.

When the conductive filament 112 is formed in the transparent electrode 110, a metal electrode pad 114a is formed on the transparent electrode 110 (e). In this case, the metal electrode pad 114a may be formed by removing the electrode 118 for forming the metal electrode pad 114a and forming a separate metal electrode pad 114a. Alternatively, as shown in (e) The metal electrode pad 114a may be formed by further depositing a metal on the forming electrode 118 by using the metal electrode pad 120. FIG.

Next, the second semiconductor layer 108 and the active layer 106 are sequentially etched from the transparent electrode 110 so that the first semiconductor layer 104 is exposed, in the same manner as in the usual horizontal-type light-emitting element fabricating process, An n-type electrode pad 114b is formed on the first semiconductor layer 104 (f).

In the embodiment described above, it is possible that some of the conductive filaments 112 formed in the transparent electrode 110 are not connected to other conductive filaments 112. In this case, the current flowing into the transparent electrode 110 is locally concentrated without being diffused over the entire transparent electrode 110, so that the second semiconductor layer 108 contacting the transparent electrode 110 also locally has current A concentrated problem may arise.

11A and 11B illustrate the structure of a light emitting device according to a preferred embodiment of the present invention for solving such a current concentration problem.

11A and 11B, in order to improve the current spreading property of the transparent electrode 110, a current diffusion layer 122 (not shown) for interconnecting the conductive filaments 112 formed on the transparent electrode 110 Is formed on the upper surface or the lower surface of the transparent electrode 110. [ At this time, the current diffusion layer 122 is made of CNT or graphene.

11A shows an example in which the current diffusion layer 122 is formed between the transparent electrode 110 and the second semiconductor layer 108. FIG. 11B shows an example in which the current diffusion layer 122 is formed on the transparent electrode 110 Respectively.

CNT or graphene is excellent in conductivity and light transmittance. In the present invention, the current diffusion layer 122 is formed of CNT or graphene so as to contact one surface of the transparent electrode 110 by using such a characteristic, The current flowing into the transparent electrode 110 is diffused to the entire region of the second semiconductor layer 108 by connecting the conductive filaments 112 of the first semiconductor layer 110 to each other.

At this time, as the current diffusion layer 122 is formed thicker, the internal CNTs or graphenes are mutually connected, thereby increasing the probability that the conductive filaments 112 are connected to each other, thereby improving the conductivity of the transparent electrode 110, . Therefore, it is preferable that the current diffusion layer 122 of the present invention is formed as thin as possible within a range that the conductive filaments 112 of the transparent electrode 110 are connected to each other, but the transmittance is not hindered. In the embodiment of the present invention, the current diffusion layer 122 is formed to a thickness of about 2 nm to about 100 nm. 2 nm is the minimum thickness capable of forming CNT and graphene in a single layer, and 100 nm is the maximum thickness capable of maintaining the transmittance of light at 80% or more.

11A and 11B, except that the current diffusion layer 122 is formed immediately after the transparent electrode 110 is formed or immediately before the transparent electrode 110 is formed with CNT or graphene , And the rest of the configuration is the same as that described with reference to Figs. 9 and 10, and a detailed description thereof will be omitted.

12A and 12B are diagrams showing a configuration of a light emitting device according to a preferred embodiment of the present invention.

Referring to FIG. 12A, a light emitting device is a flip-chip structure that emits light generated in the active layer toward a substrate. In a conventional flip chip structure light emitting device, a semiconductor layer (p-GaN) And a transparent electrode having a conductive filament formed of the resistance change material of the present invention.

The substrate 130, the buffer layer 132, the first semiconductor layer 134, the active layer 136, and the second semiconductor layer 138 are sequentially formed on the substrate 130 A transparent electrode 140 is formed on the second semiconductor layer 138 by forming the conductive filament 142 and a reflective layer 144 is formed on the transparent electrode 140. In this case, the substrate 130 to the transparent electrode 140 may be formed of the same material and method as the substrate 100 to the transparent electrode 110 shown in FIG. 9, and the material of the reflective layer 144 may be general And may be formed of Ag, Al, Pt, Au, Ni, Ti, ITO, or a combination thereof used in a flip chip structure light emitting device.

After the reflective layer 144 is formed, the reflective layer 144 is bonded to the second electrode pad 150a formed on the submount substrate 152, and the first electrode pad 146 formed on the first semiconductor layer 134 is bonded to the bump (150b) formed on the submount substrate (152) by the second electrode pad (148) to receive a current.

 The current injected through the second electrode pad 150a is applied to the transparent electrode 140 through the reflective layer 144 and the entirety of the entire second semiconductor layer 138 through the conductive filament 142 formed on the transparent electrode 140. [ .

 The light generated in the active layer 136 is directed to the upper side where the first semiconductor layer 134 is located and the second semiconductor layer 138 is positioned downward and the downwardly directed light passes through the transparent electrode 140, And is then emitted upward through the semiconductor substrate 130 toward the upper side.

Since the transparent electrode 140 according to the present invention is in a low resistance state by the conductive filament 142, it exhibits good ohmic contact characteristics with the second semiconductor layer 138 and the reflective layer 140, and has a high transmittance And exhibits a high light transmittance.

13 is a view for explaining a method of manufacturing a light emitting device according to a preferred embodiment of the present invention.

13A to 13D, the transparent electrode 140 having the conductive filament 142 is formed on the second semiconductor layer 138 (FIG. 13A) by performing the steps of FIGS. 10A to 10D (A), the forming electrode is removed, and a reflective layer 144 is formed on the transparent electrode 140 (b). The reflective layer 144 may be formed on the entire surface of the transparent electrode 140 and may be formed using a metal mask 158 so as to form the first electrode pad 146 on the first semiconductor layer 134, May be formed only in an area other than the area.

Next, in order to form the first electrode pad 146 on the first semiconductor layer 134, a predetermined period of the light emitting element is formed such that the first semiconductor layer 134 is exposed from the transparent electrode 140 (or the reflective layer 144) After the region is etched, a first electrode pad 146 is formed on the first semiconductor layer 134 (c). Next, a submount substrate 152 on which the second electrode pad 150a and the third electrode pad 150b are formed is prepared, the reflection layer 144 and the second electrode pad 150a are bonded to each other, (D), the light emitting device is inverted and connected to the submount substrate 152 so that the third electrode pad 150b and the first electrode pad 146 are connected to each other.

12B shows a modified embodiment of the preferred embodiment of the present invention in which a portion of the conductive filament 142 formed on the transparent electrode 140 is not connected to other conductive filaments 142, The current diffusion layer 152 formed of CNT or graphene is formed on the second semiconductor layer 138 and the transparent electrode 140 in order to prevent intensive injection into the second semiconductor layer 138 only through the conductive filament 142. [ Lt; / RTI > Although the current diffusion layer 152 is illustrated as being added between the second semiconductor layer 138 and the transparent electrode 140 in Figure 12B, the current diffusion layer 152 may be formed between the transparent electrode 140 and the reflective layer 144 It can be added as described above with reference to FIGS. 11A and 11B.

14A and 14B are diagrams showing a structure of a light emitting device according to a preferred embodiment of the present invention.

A light emitting device according to an embodiment of the present invention is a vertical light emitting device. In a general vertical light emitting device, a transparent electrode having a conductive filament formed between a reflective layer and a second semiconductor layer (for example, a p- Is further formed.

14A, a submount substrate 178, a bonding layer 176, a reflective layer 174, a transparent electrode 170, a second semiconductor layer 168, an active layer 166, a first semiconductor layer 164, And an electrode pad 180 are sequentially formed. The reflective layer 174 may be formed of a metal such as Ag, Al, Pt, Au, Ni, Ti, ITO or a combination thereof. 174 are formed on the metal substrate 160 and reflect light generated from the active layer 166 to be directed upward.

 As described above, the transparent electrode 170 formed on the reflective layer 174 can transmit light in the ultraviolet region. When a voltage higher than a threshold voltage unique to the material is applied, the conductive filament 172 is formed inside the transparent electrode 170, State is changed from a high-resistance state to a low-resistance state. The transparent electrode 170 is subjected to a forming process to form a conductive filament 172 therein so that a low resistance state is maintained and a current applied from the reflective layer 174 is applied to the conductive filament 172 And is injected into the second semiconductor layer 168. [0064]

The second semiconductor layer 168 is a p-type doped semiconductor layer. In a preferred embodiment of the present invention, the second semiconductor layer 168 may be formed of a p-AlGaN single layer to emit light in the ultraviolet region, or a p- the p-AlGaN layer may be formed of a general material used for manufacturing a light emitting device capable of generating light in the ultraviolet region.

The active layer 166 (MQW) is preferably formed of Al (In) GaN / (In) GaN so that light in the ultraviolet region can be generated. However, the material is not limited as long as it can emit light in the ultraviolet region . The first semiconductor layer 164 is an n-type doped semiconductor layer. In the preferred embodiment of the present invention, the first semiconductor layer 164 is formed of n-AlGaN to emit light in the ultraviolet region. However, Or may be formed of a general material used for manufacturing the device. In the above-described embodiments, the first semiconductor layer 164 and the second semiconductor layer 168 are each a semiconductor layer doped with n-type or p-type, respectively, but vice versa.

15 is a view illustrating a method of manufacturing a light emitting device according to a preferred embodiment of the present invention.

15, steps similar to those of steps (a) to (d) of FIG. 10 are performed to sequentially form a buffer layer 162, a first semiconductor layer 164, The second semiconductor layer 168 and the transparent electrode 170 are formed and the transparent filament 172 is formed by forming the transparent electrode 170 to reduce the resistance state of the transparent electrode 170 (A).

In this case, the buffer layer 162 may be formed of an undoped gallium nitride (Un-doped GaN) layer, the first semiconductor layer 164 may be formed of an n-AlGaN layer, and the active layer 166 MQW may be formed of Al (In) GaN / (In) GaN so that light in the ultraviolet region may be generated and the second semiconductor layer 168 may be formed of a p-AlGaN single layer or p- May be formed as a thin film.

As described above, the transparent filament 172 formed on the second semiconductor layer 168 has high transmittance to ultraviolet rays and a voltage exceeding a threshold voltage is formed, and the conductive filament 172 is formed therein, The conductive filaments 172 are formed in the inner portion of the substrate. Since the examples of the resistance change material have been described above, a detailed description thereof will be omitted.

Thereafter, a reflective layer 174 is formed of a metal such as Ag or Al on the transparent electrode 170, and a bonding layer 176 for bonding with the submount substrate 176 is formed thereon to complete the light emitting structure (b).

Next, the bonding layer 176 of the light emitting structure and the submount substrate 178 are bonded to each other so that the sapphire substrate 160 faces upward. In order to separate the sapphire substrate 160 from the light emitting device, A UV laser of 245 to 305 nm is irradiated. The irradiated UV laser is absorbed in the buffer layer 162, and the GaN material of the buffer layer 162 is separated into Ga and N 2, thereby separating the sapphire substrate 160 from the light emitting element (c).

Next, the remaining material of the buffer layer 162 remaining on the first semiconductor layer 164 is removed, and an n-type electrode pad is formed on the first semiconductor layer 164 to complete the light emitting element (d).

In order to prevent the conductive filaments 172 of the transparent electrode 170 from being interconnected with other conductive filaments 172 so that the current is concentrated in a certain region, the transparent electrode 170 and the second A current diffusion layer 186 formed of CNT or graphene may be further formed between the semiconductor layers 168 or a current diffusion layer 186 formed of CNT or graphene may be formed on the transparent electrode 170, 174 may be formed. A current diffusion layer 186 is formed between the second semiconductor layer 168 and the reflective layer 174, as shown in Fig. 14B. The current flowing through the reflective layer 174 is firstly diffused through the conductive filament 172 of the transparent electrode 170 and diffused into the entirety of the second semiconductor layer 168 from the current diffusion layer in contact with the transparent electrode 170 A current is uniformly injected.

On the other hand, as described above, even when the current diffusion layer 186 is formed between the transparent electrode 170 and the reflective layer 174, the above-described effects can be obtained.

The light emitting element described above also has a high light transmittance to light in the ultraviolet region, forms a conductive filament and forms a transparent electrode using a resistance change material exhibiting good ohmic contact characteristics, thereby improving the light transmittance and electrical characteristics of the entire light emitting element do.

16 is a view illustrating a structure of a vertical light emitting device having a transparent electrode according to a preferred embodiment of the present invention.

16, a vertical light emitting device includes a reflective layer 204, a second semiconductor layer 202, an active layer 200, a first semiconductor layer 198, and a transparent electrode 194 on a submount substrate 210 And an n-type electrode pad 208 is formed on the transparent electrode 194. As shown in Fig.

15, the transparent electrode 194 is formed on the first semiconductor layer 198, and the materials and characteristics of the remaining components are the same as those in the embodiment of FIG.

17 is a view illustrating a process of manufacturing a vertical light emitting device according to a preferred embodiment of the present invention.

17A, a buffer layer 192 is formed on a substrate 190 used for manufacturing a vertical type light emitting device such as a sapphire substrate, a transparent layer 192 is formed on the buffer layer 192 using a resistance change material, Electrode 194 is formed. The buffer layer 192 may be formed of GaN, AlN or the like, and the material used for the transparent electrode is as described above.

The transparent electrode 194 is formed of a plurality of layers, and the refractive index of each layer is gradually increased in the upward direction (toward the first semiconductor layer 198). When the light emitting device is completed, the refractive index It is possible to further improve the light efficiency by reducing the total reflection due to the difference.

Next, an n-type first semiconductor layer 198 (for example, n-GaN, n-AlGaN or the like) is formed on the transparent electrode 194 and an active layer Type second semiconductor layer 202 (for example, p-GaN, p-AlGaN or the like) is formed on the active layer 210 and the reflective layer 210 is formed on the second semiconductor layer 202, (204). The reflective layer 204 may be made of a material generally used for forming a reflective film in an LED process, such as Ag, Al, Pt, Au, Ni, Ti, ITO or a combination thereof.

17B, an adhesive layer 206 for bonding with the submount substrate 210 is formed on the reflective layer 204, and a sapphire substrate 190 is formed on the upper surface of the sapphire substrate 190. In this case, The adhesive layer 206 and the submount substrate 210 are bonded to each other so that the sapphire substrate 190 is separated therefrom so that a UV laser of 245 to 305 nm is irradiated through the sapphire substrate 190.

The irradiated laser is transmitted through the substrate 190 and absorbed at the interface between the substrate 190 and the buffer layer 192 to separate the buffer layer 192 and the substrate 190. When the buffer layer 192 is formed of GaN, the GaN of the buffer layer 192 absorbing the UV laser is separated into Ga and N2. At this time, N 2 formed is released to the outside and only Ga remains at the interface. Ga having a melting point of about 30 캜 is melted by the applied heat, and thus the substrate 190 is separated.

Next, as shown in FIG. 17C, the remaining buffer layer 192 is removed by an etching process so that the transparent electrode 194 is exposed after the substrate 190 is separated, and the transparent electrode 194 (Not shown) is formed on the photoresist layer 194 and a photolithography process is performed to form a pattern for forming the forming electrode 212 in a part of the region where the n-type metal pad 208 is to be formed in the photoresist layer Forming electrode 212 is formed in the pattern by performing an e-beam, a sputtering or other metal deposition process, and then a lift-off process is performed to remove the forming electrode 212 The photoresist layer is removed to complete the forming electrode 212.

17 (d), when a voltage equal to or higher than a threshold voltage inherent to the material is applied to the forming electrode 212 formed on the transparent electrode 194, a foaming process due to electrical breakdown A conductive filament 196 is formed inside the transparent electrode 194 which is an insulating material and the resistance state of the transparent electrode 194 changes from a high resistance state to a low resistance state.

At this time, before performing the forming process, a concave-convex pattern may be additionally formed on the surface of the transparent electrode 194 to further improve the light efficiency. A known method can be applied to the method of forming the concave-convex pattern on the transparent electrode 194, so a detailed description thereof will be omitted.

When the conductive filament 196 is formed in the transparent electrode 194, an n-type metal electrode pad 208 is formed on the transparent electrode 194 as shown in (e). In this case, the metal electrode pad 208 may be formed by removing the electrode 212 for forming the metal electrode pad 208, forming a separate metal electrode pad, or by using a mask (not shown) The n-type metal electrode pad 208 may be formed by depositing a metal on the n-type metal electrode pad 208.

On the other hand, some of the conductive filaments 196 formed in the transparent electrode 194 may not be connected to other conductive filaments 196. In this case, the current flowing into the transparent electrode 194 is locally concentrated without being diffused over the entire transparent electrode 194, so that even in the first semiconductor layer 198 contacting the transparent electrode 194, There is a possibility that a concentrated problem may occur.

18A and 18B show the structure of a light emitting device according to a preferred embodiment of the present invention.

18A and 18B, in order to improve the current spreading property of the transparent electrode 194, a CNT (Carbon Nano (CNT)) interconnecting the conductive filaments 196 formed on the transparent electrode 194 Tube or graphene is formed on the upper surface or the lower surface of the transparent electrode 194. The current diffusion layers 214,

18A shows an example in which a current diffusion layer 214 implemented with CNT or graphene is formed between the transparent electrode 194 and the first semiconductor layer 198. In FIG. 18B, a current diffusion layer (216) is formed on the transparent electrode (194).

CNT or graphene is excellent in conductivity and light transmittance. In the present invention, current diffusion layers 214 and 216 are formed of CNT or graphene so as to contact one surface of the transparent electrode 194, The current flowing into the transparent electrode 194 is diffused to the entire region of the first semiconductor layer 198. In addition, The degree of change in transmittance and conductivity of the current diffusion layers 214 and 216 and the optimal thickness are as described in the above-described embodiments.

19 is a view showing a structure of an organic light emitting diode according to a preferred embodiment of the present invention.

Referring to FIG. 19, the organic light emitting device according to the present invention includes a first electrode 222, an organic material layer 230, and a transparent electrode 230 formed on a substrate 220, Two electrodes 224 are formed.

The organic material layer 230 may be formed in a structure in which a hole injecting layer 231, a hole transporting layer 233, a light emitting layer 235, an electron transporting layer 237, and an electron injecting layer 239 are sequentially formed. 230) includes a hole injection layer 231 to an electron injection layer 239. [ The structure from the substrate 220 to the electron injection layer 239 can be applied to all currently known organic light emitting devices.

On the other hand, a second electrode 224 of a transparent material of the present invention is formed on the electron injection layer 239. The second electrode 224 is formed of a transparent insulating material (resistance change material) having a high transmittance to light including an ultraviolet ray region and a resistance state changed by an applied electric field. The production process of the resistance variable material and the conductive filament used in the present invention is as described in the above-described embodiment.

The current injected into the second electrode 224 as the transparent electrode is diffused into the entire region through the conductive filament 226 connected to each other in the second electrode 224 so that the whole of the electron injection layer 239 And all the light generated in the light emitting layer 235 including light in the ultraviolet region flows out through the transparent electrode 224 having a large bandgap.

20 is a view for explaining a method of manufacturing an organic light emitting diode according to a preferred embodiment of the present invention.

First, an organic layer 230 including a first electrode 222 and a light emitting layer 235 is formed on a substrate 220 (a). The organic material layer 230 may be formed in a structure in which the hole injecting layer 231, the hole transporting layer 233, the light emitting layer 235, the electron transporting layer 237, and the electron injecting layer 239 are sequentially formed .

Next, a second electrode 224 which is a transparent electrode is formed on the organic material layer 230 (particularly, the electron injection layer 239) (b, c, d). More specifically, a step of forming a resistance change material layer, forming a forming electrode, and applying a voltage of a voltage equal to or higher than a threshold voltage to form a conductive filament is performed. The specific steps are as described in the above embodiment.

When the conductive filament 226 is formed in the second electrode 224, a metal electrode pad 228 is formed on the second electrode 224 (see (e)). At this time, the method of forming the metal electrode pad 228 may be performed by removing the electrode 227 for forming the metal electrode pad 228 and forming a separate metal electrode pad 228, The metal electrode pad 228 may be formed by further depositing a metal on the forming electrode 227 using the metal electrode pad 229.

In order to improve the current spreading, the second electrode 224, which is a transparent electrode, is formed of a carbon nanotube (CNT) or a graphene interconnecting the conductive filaments 226 The diffusion layer 240 can be formed.

21A and 21B are views illustrating a method of manufacturing an organic light emitting diode according to a preferred embodiment of the present invention.

21A shows an example in which a current diffusion layer 240 formed of CNT or graphene is formed on the second electrode 224. In FIG. 21B, a current diffusion layer 240 formed of CNT or graphene is formed on the second electrode 224 224 and the electron injection layer 239 are formed.

CNT or graphene is excellent in conductivity and light transmittance. In the present invention, the current diffusion layer 240 is formed of CNT or graphene so as to contact one surface of the transparent electrode 224 using the above- The current flowing into the transparent electrode 224 is diffused to the entire region of the electron injection layer 239 by connecting the conductive filaments 226 of the electron injection layer 234 to the transparent electrode 224. On the other hand, the degree of change in transmittance, conductivity, and optimum thickness according to the thickness of the current diffusion layer 240 are as described in the embodiment described above.

22 is a view showing a structure of an organic light emitting device according to a preferred embodiment of the present invention.

Referring to FIG. 22, the organic light emitting device according to the present invention is a bottom emission organic light emitting device. A first electrode 254, which is a transparent electrode, is formed on a transparent glass or plastic substrate 250 And an organic material layer 260 including a light emitting layer 265 and a second electrode 252 are sequentially formed on the transparent electrode 254. The organic material layer 260 may be formed in a structure in which a hole injection layer 261, a hole transport layer 263, a light emitting layer 265, an electron transport layer 267, and an electron injection layer 269 are sequentially formed.

The first electrode 254 formed on the transparent substrate 250 is formed of a resistance change material in the same manner as the second electrode 224 of the first embodiment described above and the forming process is performed to form the conductive filament 256 therein. And the conductive filaments 256 are connected to each other to maintain a low resistance state in which current flows well. Accordingly, the first electrode 254 not only has a very high transmittance to the light of the UV region as well as the light of the visible region, but also forms an ohmic contact with the hole injection layer 261, thereby reducing the driving power of the organic light emitting element .

23 is a view for explaining a method of manufacturing an organic light emitting diode according to a preferred embodiment of the present invention.

First, a first electrode 254 is formed of a resistance change material on a transparent glass substrate 250 or a transparent plastic substrate 250 (a).

Next, a first electrode 254 which is a transparent electrode is formed (b, c, d). More specifically, a step of forming a resistance change material layer, forming a forming electrode, and applying a voltage of a voltage equal to or higher than a threshold voltage to form a conductive filament is performed. The specific steps are as described in the above embodiment.

A hole injection layer 261, a hole transport layer 263, a light emitting layer 265, an electron transport layer 267, an electron injection layer 263, and a hole injection layer 263 are formed on the first electrode 254 after the forming process of the first electrode 254, A layer 269, and a second electrode 252 are sequentially formed (e). In the process of forming the hole injection layer 261 to the second electrode 252, a manufacturing process of a conventional bottom emission organic light emitting device can be applied as it is.

24A and 24B are diagrams showing a structure of an organic light emitting diode according to a preferred embodiment of the present invention. 24A and 24B, in order to improve the current diffusion efficiency, the current diffusion layer 270 is formed of CNT or the like so as to be in contact with the upper surface or the lower surface of the transparent electrode, similarly to the embodiment shown in FIGS. 21A and 21B It is formed by graphene. 24A shows an example in which a current diffusion layer 270 is formed on a first electrode 254 which is a transparent electrode, FIG. 24B shows an example in which a current diffusion layer 270 is formed on a transparent substrate 250, One electrode 254 is formed.

In the example shown in FIG. 24A, the holes are first diffused into the entire region of the organic light emitting element by the current diffusion layer 270, injected into the first electrode 254 which is a transparent electrode, The holes are uniformly injected into the hole injecting layer 261. [0251] As shown in FIG. In the example shown in FIG. 24B, the holes are primarily diffused to the entire region of the organic light emitting device by the transparent electrode 254 and injected into the current diffusion layer 270, and secondarily, The holes are uniformly injected into the hole injection layer 261 by diffusing into the entire device region.

25A to 25C are diagrams showing a configuration of a light receiving element according to a preferred embodiment of the present invention.

25A, the light receiving element includes a transparent electrode 304 and a counter electrode 302 on each side of the photoelectric conversion layer 300 with a photoelectric conversion layer 300 for absorbing light and converting the light into electrical energy, Respectively.

The photoelectric conversion layer 300 may be formed in a PN junction structure in accordance with an example in which a light receiving element is implemented. The photoelectric conversion layer 300 may be formed in a structure in which light energy is converted into electric energy by absorbing light and generating electron- And may be formed in a PIN layer structure (a structure in which a p-type semiconductor layer and an n-type semiconductor layer are bonded to both sides of an i-type semiconductor layer which is an intrinsic semiconductor layer).

The counter electrode 302 is formed to correspond to the transparent electrode 304 to be described later, and can be implemented in the same manner as an electrode generally used in a solar cell, a photodiode, or the like. The light receiving element needs two electrodes, one of which is a transparent electrode and the other of which is a counter electrode 302. Therefore, it should be noted that the counter electrode 302 in the preferred embodiment of the present invention is not related to the physical arrangement relationship with the transparent electrode 304. [

The transparent electrode 304 transmits external light to provide light to the photoelectric conversion layer 300. The transparent electrode 304 is formed of a transparent material (resistance change material) in which the resistance state is changed by an applied electric field while the transmittance to light including the ultraviolet ray region is high.

(Resistance change material) that has a high transmittance to light including an ultraviolet ray region and changes its resistance state by an applied electric field. The production process of the resistance variable material and the conductive filament used in the present invention is as described in the above-described embodiment.

A method of manufacturing the above-described light receiving element will be briefly described. A counter electrode 302 is formed on a substrate (not shown), and a photoelectric conversion layer 300 is formed thereon. The photoelectric conversion layer 300 may be formed of a PN junction structure or a PIN structure (a structure in which a p-type semiconductor layer and an n-type semiconductor layer are bonded to both sides of an i-type semiconductor layer which is an intrinsic semiconductor layer).

Next, a transparent electrode 304 is formed as a resistance change material on the photoelectric conversion layer 300, and a voltage exceeding a threshold voltage unique to the resistance change material is applied to cause an electrical break down phenomenon, thereby forming a forming process. The conductive filament 306 is formed in the transparent electrode 304. [ In addition, an electrode pad may be formed on one side of the transparent electrode 304.

Meanwhile, in the above-described light-receiving device manufacturing method, the counter electrode 302 is formed on a substrate. However, the transparent electrode 304 may be formed of a resistance-changing material on a transparent substrate made of glass, A forming process may be performed to form the conductive filament 306, and the photoelectric conversion layer 300 and the counter electrode 302 may be sequentially formed thereon.

In order to improve the current diffusion characteristics of the transparent electrode 304, a current diffusion layer formed of a carbon nanotube (CNT) or graphene interconnecting the conductive filaments 306 formed on the transparent electrode 304 May be further formed on the upper surface or the lower surface of the transparent electrode 304.

25B shows an example in which a current diffusion layer 308 implemented with CNT or graphene is formed between the transparent electrode 304 and the photoelectric conversion layer 300, and FIG. 25C shows an example in which a current diffusion layer 308 are formed on the opposite side of the surface of the transparent electrode 304 which is in contact with the photoelectric conversion layer 300.

CNT or graphene is excellent in conductivity and light transmittance. In the present invention, the current diffusion layer 308 is formed of CNT or graphene to contact one surface of the transparent electrode 304 by using such a characteristic, 304 are connected to each other, the current flowing in the light receiving element can be uniformly spread over the entire region. On the other hand, the degree of change in transmittance and conductivity and optimum thickness according to the thickness of the current diffusion layer 308 are as described in the above-described embodiment.

25A to 25C, a light-receiving element having a transparent electrode according to a preferred embodiment of the present invention and a manufacturing method thereof have been described. Hereinafter, embodiments in which the light receiving element is implemented as a photodiode for ultraviolet ray and a solar battery, respectively, will be described. It should be noted, however, that the structure of a photodiode for ultraviolet light and a solar cell to be described later are basically included in the structure of the light receiving element described with reference to Fig. 25A.

26 is a diagram showing an embodiment in which the light receiving element is implemented as a photodiode for ultraviolet rays according to a preferred embodiment of the present invention.

The buffer layer 312, the n-type semiconductor layer 322, the active layer 324 (intrinsic semiconductor layer), and the p-type semiconductor layer 326 are sequentially formed on the sapphire substrate 310, A transparent electrode 314 is formed on the p-type semiconductor layer 326 and a p-type electrode pad 330 is formed on the transparent electrode 314. In addition, an n-type electrode pad 332 is formed on the n-type semiconductor layer 322 so that one side of the n-type semiconductor layer 322 is exposed.

In a preferred embodiment of the invention, the buffer layer 312 was formed in the GaN layer, n-type semiconductor layer 322 is a n-Al _x Ga _{1 -} was formed by _x N layer, an active layer 324 has i-Al _x Ga _{1 - x} N layer, and the p-type semiconductor layer 326 was formed of a p-Al _x Ga _{1 - x} N layer.

The transparent electrode 314 is formed of the resistance change material as described above and exhibits good light transmittance not only in the visible light region but also in the ultraviolet ray region and the voltage exceeding the threshold voltage unique to the transparent electrode 314 material is applied, The conductive filament 316 is formed therein to exhibit a high conduction characteristic, so that a good ohmic contact is established with the p-type semiconductor layer 326 in contact therewith.

In the case of the conventional photodiode for ultraviolet rays, a metal electrode pad is directly formed on the p-type semiconductor layer without a transparent electrode. However, since the band gap difference between the metal electrode pad and the p-type semiconductor layer is very large, Problems existed. In order to solve the problem of lowering the ohmic characteristic, a method of forming a metal electrode in a large area has been proposed. However, in this case, the area of the light introduced into the semiconductor layer is greatly reduced, thereby deteriorating the performance of the entire photodiode Respectively.

However, as described above, the transparent electrode 314 of the present invention can improve the electrical conductivity of the transparent electrode 314 by forming the conductive filament 316 therein, thus exhibiting good light transmission characteristics At the same time, good ohmic contact characteristics with the p-type semiconductor layer 326 can be achieved.

27 is a view for explaining a process of manufacturing a photodiode for ultraviolet rays according to a preferred embodiment of the present invention.

First, the sapphire substrate 310 sequentially to the buffer layer 312 on a (GaN layer), n type semiconductor layer _{(322) (n-Al x} Ga 1 - x N layer), an active layer (324) (intrinsic semiconductor layer: i- Al _x Ga _{1 - x} N layer) and a p-type semiconductor layer 326 (p-Al _x Ga _1-x N layer) are formed. The process of forming the p-type semiconductor layer 326 from the sapphire substrate 310 is the same as the general photodiode fabrication process for ultraviolet rays, and thus a detailed description thereof will be omitted.

Next, a transparent electrode 314 is formed on the p-type semiconductor layer 326 by using a resistance change material (b, c, d). More specifically, a step of forming a resistance change material layer, forming a forming electrode, and applying a voltage of a voltage equal to or higher than a threshold voltage to form a conductive filament is performed. The specific steps are as described in the above embodiment.

When the conductive filament 316 is formed in the transparent electrode 314, a p-type metal electrode pad 330 is formed on the transparent electrode 314 (d). At this time, the method of forming the p-type electrode pad 330 may be performed by removing the electrode 317 for forming and forming a separate metal electrode pad, or by using the mask 318 to form the forming electrode 317, The p-type metal electrode pad 330 may be formed.

Next, the p-type semiconductor layer 326 and the active layer 324 are sequentially etched from the transparent electrode 314 so that the n-type semiconductor layer 322 is exposed, and an n-type electrode pad is formed on the n-type semiconductor layer 322 Thereby completing the photodiode for ultraviolet rays (e).

Although the photoelectric conversion layer 320 is formed of the n-type semiconductor layer 322, the active layer 324 (intrinsic semiconductor layer), and the p-type semiconductor layer 326 in the above embodiment, (320) may be implemented by only a PN junction.

Up to now, a photodiode for ultraviolet ray according to a preferred embodiment of the present invention and a manufacturing method thereof have been described. On the other hand, some of the conductive filaments 316 formed in the transparent electrode 314 may not be connected to other conductive filaments 316.

28A and 28B show a photodiode for an ultraviolet ray according to a preferred embodiment of the present invention.

(Carbon Nano Tube) or graphene interconnecting the conductive filaments 316 formed on the transparent electrode 314 in order to improve current spreading of the transparent electrode 314 The current diffusion layers 334 and 336 are formed on the upper surface or the lower surface of the transparent electrode 314.

28A shows an example in which a current diffusion layer 334 formed of CNT or graphene is formed on the transparent electrode 314 and in FIG. 28B, a current diffusion layer 336 formed of CNT or graphene is formed on the transparent electrode 314 ) And the p-type semiconductor layer 326 are shown.

CNT or graphene is excellent in conductivity and light transmittance. In the present invention, current diffusion layers 334 and 336 are formed of CNT or graphene to contact one surface of the transparent electrode 314 to form a transparent electrode The current flowing into the transparent electrode 314 is diffused to the entire region of the photoelectric conversion layer 320. In addition, On the other hand, the degree of change in transmittance and conductivity of the current diffusion layers 334 and 336 and the optimal thickness are as described in the above-described embodiments.

An example in which the light receiving element according to the preferred embodiment of the present invention is applied to a photodiode for ultraviolet rays has been described. The photodiode used in the conventional visible light region has the same structure as that of a solar cell to be described later with reference to FIGS. 29 to 31B, and a detailed description thereof will be omitted.

29 is a diagram showing an example in which a light receiving element is implemented by a solar cell according to a preferred embodiment of the present invention.

A solar cell according to one preferred embodiment of the present invention has a structure in which a transparent electrode 404 and a counter electrode 402 are bonded to both sides of a photoelectric conversion layer 410. At this time, the supporting substrate 400, such as a glass substrate, may be formed to contact the transparent electrode 404 or to be in contact with the counter electrode 402.

29, the photoelectric conversion layer 410 may be formed in a PN junction structure or a PIN junction layer in which n-type, i-type, and p-type semiconductor layers are bonded. Although the transparent electrode 404 is in contact with the p-type semiconductor layer 414 and the counter electrode 402 is in contact with the n-type semiconductor layer 412 in the illustrated example, And the counter electrode 402 may be configured to contact the p-type semiconductor layer.

The external light incident through the transparent electrode 404 passes through the transparent electrode 404 and flows into the photoelectric conversion layer 410, Holes and electrons are generated in the photoelectric conversion layer 410 due to the energy. At this time, the holes (+) move to the P-type semiconductor layer due to the electric field generated at the PN junction, The electrons are moved to the N-type semiconductor layer and a potential is generated.

The transparent electrode 404 may be formed of the same resistance change material as that of the transparent electrode 404 shown in FIGS. 25A and 26, and a voltage exceeding a threshold value unique to the resistance change material may be applied to cause the insulation breakdown phenomenon, The conductive filament 406 is formed. Therefore, the transparent electrode 404 exhibits high transmittance not only in the visible light region but also in the ultraviolet region, and exhibits a high electrical conductivity property by the conductive filament 406.

30 is a view for explaining a process of manufacturing a solar cell having a transparent electrode 404 according to a preferred embodiment of the present invention.

First, the counter electrode 402 and the photoelectric conversion layer 410 are formed on a substrate in the same manner as a general solar cell manufacturing process, and the transparent electrode 404 is formed of a resistance-changing material so as to be in contact with the photoelectric conversion layer 410 (b, c). More specifically, a step of forming a resistance change material layer, forming a forming electrode, and applying a voltage of a voltage equal to or higher than a threshold voltage to form a conductive filament is performed. The specific steps are as described in the above embodiment.

When the conductive filament 406 is formed in the transparent electrode 404, an electrode pad 408 is formed on the transparent electrode 404 (FIG. At this time, the electrode 407 for performing the forming may be removed and another metal electrode pad may be formed, or a metal may be deposited on the forming electrode 407 by using a mask (not shown) .

31A and 31B are views showing a solar cell according to a preferred embodiment of the present invention.

In the illustrated example, a carbon nanotube (CNT) or a graphene (CNT) interconnecting the conductive filaments 406 formed on the transparent electrode 404 is formed in order to improve current spreading of the transparent electrode 404 the current diffusion layers 420 and 422 are formed on the upper surface or the lower surface of the transparent electrode 404.

31A shows an example in which a current diffusion layer 420 formed of CNT or graphene is formed on the transparent electrode 404 and a current diffusion layer 422 formed of CNT or graphene is formed on the transparent electrode 404 in FIG. And the photoelectric conversion layer 410 are formed.

31A, a current diffusion layer 420 is formed of CNT or graphene immediately after the formation of the conductive filament 406 by performing a forming process on the transparent electrode 404.

31B, after the photoelectric conversion layer 410 is formed, a current diffusion layer 422 is formed of CNT or graphene on the photoelectric conversion layer 410, and a transparent electrode 404 is formed thereon .

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

10: semiconductor layer 20: transparent electrode
22: conductive filament 30: metal electrode pad
40: photoresist layer 50: mask
60: CNT layer or graphene layer
100, 130: substrate 102, 132: buffer layer
104, 134: first semiconductor layer 106, 136: active layer
108, 138: second semiconductor layer 110, 140: transparent electrode
112, 142: Conductive filament
114a, 114b, 146, 180: electrode pads
116: photoresist 118, 156, 182: forming electrode
144, 174: reflective layer 148: bump
150a: second electrode pad 150b: third electrode pad
152, 178: Submount substrate 110, 154, 186: Current diffusion layer
190: substrate 192: buffer layer
194: Transparent electrode 196: Conductive filament
214, 216: current diffusion layer
198: first semiconductor layer 200: active layer
202: second semiconductor layer 204: reflective layer
206: adhesive layer 208: n-type electrode pad
210: Sub-mount substrate 212: Forming electrode
220, 250: substrate 222, 252: second electrode
230, 260: organic layer 231, 261: hole injection layer
233, 263: a hole transporting layer 235, 265: a light emitting layer
237, 267: electron transport layer 239, 269: electron injection layer
224, 254: transparent electrode (first electrode) 226, 256: conductive filament
240, and 270: current diffusion layer
300: photoelectric conversion layer 302: opposing electrode
304: transparent electrode 306: conductive filament
308: current diffusion layer
310: substrate 312: buffer layer
320: photoelectric conversion layer 322: n-type semiconductor layer
324: active layer 326: p-type semiconductor layer
314: Transparent electrode 316: Conductive filament
334: Current diffusion layer
400: substrate 402: opposing electrode
410: photoelectric conversion layer 412: n-type semiconductor layer
414: p-type semiconductor layer 404: transparent electrode
406: Conductive filament

Claims (52)

In a semiconductor device,
The semiconductor layer and /
And a transparent electrode having one side in contact with the semiconductor layer,
Wherein the transparent electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. The method according to claim 1,
And a metal electrode pad or a metal electrode for forming contact with the other surface of the transparent electrode. The method according to claim 1,
Wherein the conductive filament is formed by a voltage equal to or higher than a threshold voltage applied through a metal electrode for forming contact with the other surface of the transparent electrode. The method according to claim 1,
And the transparent electrode is in ohmic contact with the semiconductor layer. The method according to claim 1,
Wherein the semiconductor layer is doped with n-type or p-type. The method according to claim 1,
Wherein the transparent electrode is formed of at least one of a transparent oxide-based material, a transparent nitride-based material, a transparent poly-based material, and a transparent nanomaterial. The method according to claim 1,
And a current diffusion layer formed between the transparent electrode and the semiconductor layer,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer. 3. The method of claim 2,
And a current diffusion layer formed between the metal electrode pad and the transparent electrode,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer. A method of manufacturing a semiconductor device,
Providing a semiconductor layer;
And forming a transparent electrode on one surface of the semiconductor layer,
The step of forming the transparent electrode
Forming a resistance-change material layer on one surface of the semiconductor layer, and
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance change material layer. 10. The method of claim 9,
The step of forming the transparent electrode
Forming a metal electrode for forming on the resistance change material layer,
Wherein the forming step applies a voltage equal to or higher than the threshold voltage through the metal electrode for forming. 11. The method of claim 10,
The forming of the metal electrode for forming
Depositing a photoresist on top of the resistance change material layer;
Forming an electrode pattern on the photoresist;
Depositing a metal on the electrode pattern; and
And removing the photoresist. 11. The method of claim 10,
Removing the foaming metal electrode after performing the foaming step;
Forming a current diffusion layer on the resistance change material layer; And
And forming a metal electrode pad on the current diffusion layer, wherein the current diffusion layer includes a CNT layer or a graphene layer. 11. The method of claim 10,
Forming a current diffusion layer on one surface of the semiconductor layer before forming a resistance change material layer on one surface of the semiconductor layer,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer. A method of manufacturing a semiconductor device,
Providing a substrate;
Forming a transparent electrode on the substrate; and
And contacting the one surface of the transparent electrode with the semiconductor layer,
The step of forming the transparent electrode
Forming a resistance change material layer so as to be in contact with the substrate;
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance change material layer. 15. The method of claim 14,
The step of contacting one side of the transparent electrode with the semiconductor layer
Removing the substrate from the transparent electrode, and
And contacting one surface of the transparent electrode from which the substrate is removed with the semiconductor layer. 15. The method of claim 14,
The step of contacting one side of the transparent electrode with the semiconductor layer
Contacting the semiconductor layer to the other surface of the transparent electrode in contact with the substrate, and
And removing the substrate from the transparent electrode. 15. The method of claim 14,
The step of forming the transparent electrode
Forming a metal electrode for forming on the resistance change material layer,
Wherein the forming step applies a voltage equal to or higher than the threshold voltage through the metal electrode for forming. 18. The method of claim 17,
The forming of the metal electrode for forming
Depositing a photoresist on top of the resistance change material layer;
Forming an electrode pattern on the photoresist;
Depositing a metal on the electrode pattern; and
And removing the photoresist. 18. The method of claim 17,
Removing the foaming metal electrode after performing the foaming step;
Forming a current diffusion layer on the resistance change material layer; And
And forming a metal electrode pad on the current diffusion layer,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer. The method according to claim 9 or 14,
Wherein the transparent electrode is in ohmic contact with the semiconductor layer. The method according to claim 9 or 14,
Wherein the semiconductor layer is doped with n-type or p-type. The method according to claim 9 or 14,
Wherein the transparent electrode is formed of at least one of a transparent oxide-based material, a transparent nitride-based material, a transparent poly-based material, and a transparent nanomaterial. In the light emitting device,
Board,
A first semiconductor layer formed on the substrate,
An active layer formed on the first semiconductor layer,
A second semiconductor layer formed on the active layer,
A transparent electrode formed on the second semiconductor layer,
A first electrode pad formed to be in contact with the first semiconductor layer,
And a second electrode pad contacting the upper portion of the transparent electrode,
Wherein the transparent electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. 24. The method of claim 23,
A reflective layer coupled between the transparent electrode and the second electrode pad,
A submount substrate coupled to the second electrode pad and coupled to a third electrode pad spaced apart from the second electrode pad,
And a bump coupled between the third electrode pad and the first electrode pad. 25. The method of claim 24,
Wherein the first electrode pad is formed to be in contact with a predetermined region of the exposed first semiconductor layer by etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode in a direction perpendicular to the first semiconductor layer. 24. The method of claim 23,
And a buffer layer coupled between the substrate and the first semiconductor layer. In the light emitting device,
Submount substrate,
A reflective layer combined with the submount substrate through a bonding layer,
A transparent electrode coupled to the reflective layer,
A second semiconductor layer coupled to the upper portion of the transparent electrode,
An active layer formed on the second semiconductor layer,
A first semiconductor layer formed on the active layer,
And an electrode pad formed on the first semiconductor layer,
Wherein the transparent electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. In the light emitting device,
Submount substrate,
A reflective layer combined with the submount substrate through a bonding layer,
A second semiconductor layer coupled with the reflective layer,
An active layer formed on the second semiconductor layer,
A first semiconductor layer formed on the active layer,
A transparent electrode formed on the first semiconductor layer,
And an electrode pad formed on the transparent electrode,
Wherein the transparent electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. 29. The method according to any one of claims 23 to 28,
And a current diffusion layer coupled to one surface or the other surface of the transparent electrode,
Wherein the current diffusion layer includes a CNT layer or a graphene layer combined with the transparent electrode. 28. The method according to any one of claims 23 to 27,
And the transparent electrode is in ohmic contact with the second semiconductor layer. 29. The method of claim 28,
Wherein the transparent electrode is in ohmic contact with the first semiconductor layer. A method of manufacturing a light emitting device,
Forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate,
Forming a transparent electrode on the second semiconductor layer;
Exposing the first semiconductor layer by vertically etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode; And
Forming a first electrode pad in contact with an upper portion of the first semiconductor layer and a second electrode pad in contact with an upper portion of the transparent electrode,
The step of forming the transparent electrode
Forming a resistance change material layer on one surface of the second semiconductor layer;
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance-change material layer. A method of manufacturing a light emitting device,
Forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate,
Forming a transparent electrode on the second semiconductor layer;
Forming a reflective layer on the transparent electrode;
Exposing the first semiconductor layer by vertically etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode;
Forming a first electrode pad in contact with an upper portion of the first semiconductor layer
Providing a submount substrate including a second electrode pad and a third electrode pad spaced apart from each other;
Coupling the reflective layer and the second electrode pad and coupling the first electrode pad and the third electrode pad through a bump,
The step of forming the transparent electrode
Forming a resistance change material layer on one surface of the second semiconductor layer;
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance-change material layer. A method of manufacturing a light emitting device,
Forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate,
Forming a transparent electrode on the second semiconductor layer;
Forming a reflective layer on the transparent electrode;
Forming a bonding layer on the reflective layer;
Bonding the submount substrate to the bonding layer;
Exposing the first semiconductor layer by removing the substrate;
Forming an electrode pad on the first semiconductor layer,
The step of forming the transparent electrode
Forming a resistance change material layer on one surface of the second semiconductor layer;
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance-change material layer. A method of manufacturing a light emitting device,
Forming a buffer layer on the substrate;
Forming a resistance change material layer on one surface of the buffer layer;
Forming a first semiconductor layer, an active layer and a second semiconductor layer on the resistance change material layer,
Forming a reflective layer on the second semiconductor layer;
Forming a bonding layer on the reflective layer;
Bonding the submount substrate to the bonding layer;
Exposing the resistance change material layer by removing the substrate;
Forming a transparent electrode by performing a forming step on the resistance change material layer;
And forming an electrode pad on the transparent electrode,
The step of forming the transparent electrode
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance-change material layer. 35. The method according to claim 34 or 35,
Forming a current diffusion layer coupled to one surface or the other surface of the transparent electrode,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer. In the organic light emitting device,
Board,
A first electrode formed on the substrate,
An organic layer formed on the first electrode and including a light emitting layer,
A second electrode formed on the organic material layer and being a transparent electrode,
Wherein the second electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. In the organic light emitting device,
Board,
A first electrode formed on the substrate and being a transparent electrode,
An organic layer formed on the first electrode and including a light emitting layer,
And a second electrode formed on the organic material layer,
Wherein the first electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. 39. The method of claim 37 or 38,
And a current diffusion layer coupled to one surface or the other surface of the first electrode which is the transparent electrode or the second electrode which is the transparent electrode,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer. 39. The method of claim 37 or 38,
The organic layer
A hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. 39. The method of claim 37 or 38,
Wherein the first electrode as the transparent electrode or the second electrode as the transparent electrode is in ohmic contact with the organic material layer. A method of manufacturing an organic light emitting device,
Forming a first electrode on the substrate,
Forming an organic material layer including a light emitting layer on the first electrode,
And forming a second electrode that is a transparent electrode on the organic material layer,
The step of forming the second electrode
Forming a resistance-change material layer on one surface of the organic material layer;
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance-change material layer. A method of manufacturing an organic light emitting device,
Forming a first electrode which is a transparent electrode on a substrate,
Forming an organic material layer including a light emitting layer on the first electrode,
And forming a second electrode on the organic material layer,
The step of forming the first electrode
Forming a resistance change material layer so as to be in contact with the substrate;
And forming a conductive filament by applying a voltage equal to or greater than a threshold voltage to the resistance-change material layer. 44. The method of claim 42 or 43,
The organic layer
A hole injecting layer, a hole transporting layer, a light emitting layer, an electron transporting layer, and an electron injecting layer. 44. The method of claim 42 or 43,
Forming a current diffusion layer coupled to one surface or the other surface of the first electrode as the transparent electrode or the second electrode as the transparent electrode,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer. In the light receiving element,
Photoelectric conversion layer,
A transparent electrode in contact with one surface of the photoelectric conversion layer and
And an opposite electrode contacting the other surface of the photoelectric layer,
Wherein the transparent electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. In the light receiving element,
Board,
A first semiconductor layer formed on the substrate,
An active layer formed on the first semiconductor layer,
A second semiconductor layer formed on the active layer,
A transparent electrode formed on the second semiconductor layer,
A first electrode pad formed to be in contact with the first semiconductor layer,
And a second electrode pad contacting the upper portion of the transparent electrode,
Wherein the transparent electrode is made of a resistance change material and has conductivity through a conductive filament formed by applying a voltage equal to or higher than a threshold voltage to the resistance change material. 49. The method of claim 47,
Wherein the first electrode pad is formed to contact a predetermined region of the exposed first semiconductor layer by etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode in a direction perpendicular to the first electrode pad. 49. The method according to any one of claims 46 to 48,
Wherein the current diffusion layer comprises a CNT layer or a graphene layer, wherein the current diffusion layer is formed on one surface or the other surface of the transparent electrode. In the method of manufacturing a light receiving element,
Forming an opposing electrode on the substrate;
Forming a photoelectric conversion layer on the counter electrode, and
And forming a transparent electrode on the photoelectric conversion layer,
Forming a resistance change material layer such that the one surface of the resistance change material layer is in contact with the photoelectric conversion layer;
And forming a conductive filament by applying a voltage equal to or higher than a threshold voltage to the resistance change material layer. In the light receiving element manufacturing method,
Forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate,
Forming a transparent electrode on the second semiconductor layer;
Exposing the first semiconductor layer by vertically etching the first semiconductor layer, the active layer, the second semiconductor layer, and the transparent electrode; And
Forming a first electrode pad in contact with an upper portion of the first semiconductor layer and a second electrode pad in contact with an upper portion of the transparent electrode,
The step of forming the transparent electrode
Forming a resistance change material layer on one surface of the second semiconductor layer;
And forming a conductive filament by applying a voltage equal to or higher than a threshold voltage to the resistance change material layer. 52. The method of claim 51,
Forming a current diffusion layer coupled to one surface or the other surface of the transparent electrode, wherein the current diffusion layer includes a CNT layer or a graphene layer.

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