Ac-driven LED device and preparation method therefor

Abstract

The present application relates to an AC-driven LED device and a preparation method therefor. The AC-driven LED device comprises: a substrate layer; a first semiconductor layer located on a surface of the substrate layer, wherein the first semiconductor layer comprises a planar portion and a protruding portion, and the protruding portion is located on a surface of the planar portion facing away from the substrate layer; an active layer located on a surface of the protruding portion of the first semiconductor layer facing away from the substrate layer; a second semiconductor layer located on a surface of the active layer facing away from the first semiconductor layer, wherein the second semiconductor layer has a conductivity type opposite to that of the first semiconductor layer, and the protruding portion of the first semiconductor layer, the active layer, and the second semiconductor layer constitute an epitaxial layer of the LED device; a passivation layer located on a surface of the second semiconductor layer facing away from the active layer and covering a side portion of the epitaxial layer; and a side electrode located on a surface of the passivation layer facing away from the side portion of the epitaxial layer. The AC-driven LED device provided by the present application can effectively reduce the turn-on voltage of the device under AC driving, while increasing the injection current and improving the luminous brightness of the device.

Description

AC driven LED device and method of manufacturing the same

[0001] The present application claims priority to the Chinese patent application No. 202411259249.4, filed on September 9, 2024, and entitled “AC driven LED device and method of manufacturing the same”, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of AC driven LED device, in particular to an AC driven LED device and a method of manufacturing the same. BACKGROUND

[0003] Traditional light emitting diodes (LEDs) work under direct current, which has its own limitations: as the pixel size decreases, it is difficult to integrate metal electrodes on the LED device. Therefore, many researchers have proposed AC driven LED devices, which are vertical structures and have insulating layers on the top and bottom for isolation, and the light emission under AC voltage is achieved through the capacitive effect inside the device during the driving process. AC driven LEDs have feasibility and great potential in non-destructive testing and display. However, in existing AC driven LED devices, due to the presence of insulating layers at both ends of the device, a high driving voltage needs to be applied to achieve device light emission, resulting in a high turn-on voltage of the device. At the same time, due to the presence of the insulating layer of the device, the equivalent capacitance of the device under AC signal leads to small injection current of the device, resulting in low light emission intensity and poor light emission effect of the device. Therefore, a solution is needed to reduce the turn-on voltage of the AC signal driven LED device, improve the injection current, increase the light emission intensity of the device, and thus enhance the light emission effect. SUMMARY

[0004] Therefore, the present application provides an AC driven LED device and a method of manufacturing the same to solve the problem of high turn-on voltage of the AC driven LED device, small injection current of the device under AC signal, and low light emission intensity and poor light emission effect of the device.

[0005] The application provides an alternating current driven LED device, comprising: a substrate layer; a first semiconductor layer located on the surface of the substrate layer, the first semiconductor layer comprising a planar portion and a convex portion located on the surface of the planar portion away from the substrate layer; an active layer located on the surface of the convex portion of the first semiconductor layer away from the substrate layer; a second semiconductor layer located on the surface of the active layer away from the first semiconductor layer, the second semiconductor layer being opposite in conductive type to the first semiconductor layer, wherein the top second semiconductor layer and the bottom substrate layer are adapted to be connected to alternating current electrodes respectively, the convex portion of the first semiconductor layer, the active layer and the second semiconductor layer constituting an epitaxial layer of the LED device; a passivation layer located on the surface of the second semiconductor layer away from the active layer and covering the side of the epitaxial layer; and a side electrode located on the surface of the passivation layer away from the side of the epitaxial layer.

[0006] Optionally, the passivation layer is provided with a first opening on the portion of the surface of the second semiconductor layer away from the active layer, and the LED device is further provided with an upper electrode in communication with the second semiconductor layer through the first opening.

[0007] Optionally, a conductive layer is further provided between the second semiconductor layer and the passivation layer, the passivation layer is provided with a second opening on the portion of the surface of the conductive layer away from the second semiconductor layer, and the LED device is further provided with an upper electrode in communication with the conductive layer through the second opening.

[0008] Optionally, the conductive layer is an ITO conductive layer, and the passivation layer is a silicon dioxide passivation layer.

[0009] Optionally, the thickness of the passivation layer is less than the thickness of the substrate layer.

[0010] Optionally, the side electrode fully covers the surface of the passivation layer away from the side of the epitaxial layer.

[0011] Optionally, the side electrode covers the surfaces of opposite two sides of the passivation layer away from the side of the epitaxial layer.

[0012] Optionally, the passivation layer further covers the portion of the surface of the planar portion of the first semiconductor layer away from the substrate layer which is not covered by the epitaxial layer.

[0013] Optionally, the side electrode further extends and partially covers the surface of the passivation layer away from the second semiconductor layer, and extends and covers the surface of the passivation layer away from the planar portion of the first semiconductor layer.

[0014] The application further provides a manufacturing method of an AC-driven LED device, comprising the following steps: providing a substrate layer; forming a first semiconductor layer on the surface of the substrate layer, wherein the first semiconductor layer comprises a planar part and a convex part on the surface of the side of the planar part away from the substrate layer; forming an active layer on the surface of the convex part of the first semiconductor layer away from the substrate layer; forming a second semiconductor layer on the surface of the active layer away from the first semiconductor layer, wherein the second semiconductor layer is opposite to the conductive type of the first semiconductor layer; forming a passivation layer on the surface of the second semiconductor layer away from the active layer, and covering the side of an epitaxial layer, wherein the epitaxial layer is the convex part of the first semiconductor layer, the active layer and the second semiconductor layer; and forming a side electrode on the surface of the passivation layer away from the side of the epitaxial layer.

[0015] The technical scheme of the application has the following advantages:

[0016] The alternating current driven LED device provided by the application comprises a substrate layer; a first semiconductor layer located on the surface of the substrate layer, wherein the first semiconductor layer comprises a planar part and a convex part located on the surface of the side of the planar part away from the substrate layer; an active layer located on the surface of the side of the convex part of the first semiconductor layer away from the substrate layer; a second semiconductor layer located on the surface of the side of the active layer away from the first semiconductor layer, wherein the second semiconductor layer is opposite to the first semiconductor layer in the type of conduction; the convex part of the first semiconductor layer, the active layer and the second semiconductor layer constitute an epitaxial layer of the LED device; a passivation layer located on the surface of the side of the second semiconductor layer away from the active layer and covering the side of the epitaxial layer; and a side electrode located on the surface of the side of the passivation layer away from the epitaxial layer. Compared with the existing alternating current driven LED device, the passivation layer and the side electrode are arranged on the side of the epitaxial layer. In actual use, the second semiconductor layer on the top and the substrate layer on the bottom are usually connected to alternating current electrodes, the electrode on the top is connected to a high potential, and the electrode on the bottom is connected to a low potential (for example, ground), thereby forming a "top-bottom" path and realizing light emission under alternating current driving. The scheme of the application adds a side electrode. When the side electrode is also connected to a low potential (for example, ground), a "top-side" path is formed. Since the substrate layer is absent, the capacitance on the "top-side" path is larger than the capacitance on the "top-bottom" path, so that the capacitive reactance under high-frequency driving is smaller, the current on the path is increased, and more carriers are injected to realize light emission, thereby reducing the turn-on voltage. At the same time, the low potential of the side electrode deflects the carriers during the transmission process (compared with a pure vertical electric field), so that the transport distance of the carriers in the active layer is lengthened, the recombination probability is increased, the light emission intensity of the device is improved, and the light emission effect of the device is enhanced. In addition, under the influence of high-frequency electromagnetic waves, the electrical conductivity of the semiconductor material is also affected, so that the overall impedance of the device is affected. The application can improve the current injection, the light emission intensity of the device and the light emission effect of the device by adjusting the frequency and amplitude of the electromagnetic field introduced into the device under constant voltage working conditions. Therefore, the alternating current driven LED device provided by the application can effectively reduce the turn-on voltage of the LED device under alternating current driving, increase the injected current, improve the light emission intensity of the device, and further enhance the light emission effect of the device.

[0017] The AC-driven LED device preparation method provided by the application can prepare the AC-driven LED device provided by the application. The LED device produces a certain inclination angle in the etching process. The inclination angle naturally formed in the deposition and etching process of the epitaxial layer is utilized to further deposit a passivation layer and a side electrode. When the side electrode is also connected to a low potential (for example, ground), a "top-side" path is formed. Since the substrate layer is missing, the capacitance on the "top-side" path is larger than the capacitance on the "top-bottom" path. Therefore, the capacitive reactance under high-frequency driving is smaller, the current on the path is increased, more carriers are injected to realize light emission, and the turn-on voltage is reduced. At the same time, the low potential of the side electrode deflects the carrier transmission process (compared to a pure vertical electric field), the carrier transport distance in the active layer is lengthened, the recombination probability is increased, and the light emission effect of the device is improved. In addition, under the influence of high-frequency electromagnetic waves, the electrical conductivity of the semiconductor material is also affected, which affects the overall impedance of the device. The application can adjust the frequency and amplitude of the electromagnetic field introduced into the device to improve the current injection under constant voltage conditions, improve the light emission intensity of the device, enhance the light emission effect of the device. Therefore, the AC-driven LED device prepared by the AC-driven LED device preparation method provided by the application can effectively reduce the turn-on voltage of the LED device under AC driving, increase the injected current, improve the light emission intensity of the device, and further enhance the light emission effect of the device. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the specific embodiments of the application or the prior art, the drawings needed in the specific embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] FIG. 1 is a structural schematic diagram of an AC-driven LED device according to an embodiment of the application;

[0020] FIG. 2 is a structural schematic diagram of another AC-driven LED device according to an embodiment of the application;

[0021] FIG. 3 is a top view of an AC-driven LED device according to an embodiment of the application;

[0022] FIG. 4 is a top view of another AC-driven LED device according to an embodiment of the application;

[0023] FIG. 5 is a flowchart of a preparation method of an AC-driven LED device according to an embodiment of the application;

[0024] Reference numerals: 100 - substrate layer; 200 - first semiconductor layer; 300 - active layer; 400 - second semiconductor layer; 500 - passivation layer; 600 - side electrode; 700 - upper electrode; 800 - conductive layer. DETAILED DESCRIPTION

[0025] To solve the problem of high turn-on voltage of the AC-driven LED device, small injection current of the device under AC signal, low light intensity and poor light effect of the device, the application provides an AC-driven LED device, comprising: a substrate layer; a first semiconductor layer located on the surface of the substrate layer, the first semiconductor layer comprising a planar portion and a raised portion, the raised portion being located on the surface of the side of the planar portion away from the substrate layer; an active layer located on the surface of the side of the raised portion of the first semiconductor layer away from the substrate layer; a second semiconductor layer located on the surface of the side of the active layer away from the first semiconductor layer, the second semiconductor layer being opposite in conductivity type to the first semiconductor layer, wherein the top second semiconductor layer and the bottom substrate layer are adapted to be connected to AC electrodes respectively; the raised portion of the first semiconductor layer, the active layer and the second semiconductor layer constitute an epitaxial layer of the LED device; a passivation layer located on the surface of the side of the second semiconductor layer away from the active layer and covering the side of the epitaxial layer; a side electrode located on the surface of the side of the passivation layer away from the epitaxial layer.

[0026] The application also provides a manufacturing method of an AC-driven LED device, comprising the following steps: providing a substrate layer; forming a first semiconductor layer located on the surface of the substrate layer, the first semiconductor layer comprising a planar portion and a raised portion, the raised portion being located on the surface of the side of the planar portion away from the substrate layer; forming an active layer located on the surface of the side of the raised portion of the first semiconductor layer away from the substrate layer; forming a second semiconductor layer located on the surface of the side of the active layer away from the first semiconductor layer, the second semiconductor layer being opposite in conductivity type to the first semiconductor layer; forming a passivation layer located on the surface of the side of the second semiconductor layer away from the active layer and covering the side of the epitaxial layer, the epitaxial layer being the raised portion of the first semiconductor layer, the active layer and the second semiconductor layer; forming a side electrode located on the surface of the side of the passivation layer away from the epitaxial layer.

[0027] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application. In the description of the present application, it should be noted that the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0028] Embodiment 1

[0029] Referring to FIG. 1, the present embodiment provides an AC driven LED device, comprising:

[0030] a substrate layer 100;

[0031] a first semiconductor layer 200 located on the surface of the substrate layer 100, the first semiconductor layer 200 comprising a planar portion and a convex portion located on the surface of the planar portion away from the substrate layer 100;

[0032] an active layer 300 located on the surface of the convex portion of the first semiconductor layer 200 away from the substrate layer 100;

[0033] a second semiconductor layer 400 located on the surface of the active layer 300 away from the first semiconductor layer 200, the second semiconductor layer 400 being opposite in conductive type to the first semiconductor layer 200, wherein the top second semiconductor layer and the bottom substrate layer 100 are adapted to be connected to AC electrodes respectively;

[0034] the convex portion of the first semiconductor layer 200, the active layer 300 and the second semiconductor layer 400 constitute an epitaxial layer of the LED device;

[0035] a passivation layer 500 located on the surface of the second semiconductor layer 400 away from the active layer 300, and covering the side of the epitaxial layer;

[0036] a side electrode 600 located on the surface of the passivation layer 500 away from the side of the epitaxial layer.

[0037] In actual use, the top second semiconductor layer 400 and the bottom substrate layer 100 are usually connected to AC electrodes respectively, the top electrode is connected to high potential, and the bottom electrode is connected to low potential (such as ground), forming a "top-bottom" path, and realizing light emission under AC driving.

[0038] The alternating current driven LED device provided in the application adds a side electrode on the basis of the prior art. When the low potential (for example, ground) is also connected to the side electrode, a "top-side" path is formed. Since the substrate layer is absent, the capacitance on the "top-side" path is larger than the capacitance on the "top-bottom" path. Therefore, the capacitive reactance under high frequency driving is smaller, the current on the path is increased, more carriers are injected to realize light emission, and the turn-on voltage is reduced. Meanwhile, the low potential of the side electrode deflects the carriers during the carrier transport (compared to the pure vertical electric field), the transport distance of the carriers in the active layer is lengthened, the recombination probability is increased, and the light emission intensity of the device is improved. In addition, under the influence of high frequency electromagnetic waves, the conductivity of the semiconductor material is also affected, and the overall impedance of the device is affected. The application can adjust the frequency and amplitude of the electromagnetic field introduced into the device to improve the current injection under constant voltage working conditions, improve the light emission intensity of the device, and enhance the light emission effect of the device. Therefore, the alternating current driven LED device provided in the application can effectively reduce the turn-on voltage of the LED device under alternating current driving, increase the injected current, improve the light emission intensity of the device, and further enhance the light emission effect of the device.

[0039] Optionally, in the embodiment, as shown in FIG. 1, the passivation layer 500 is provided with a first opening at a portion of the passivation layer 500 located on the side surface of the second semiconductor layer 400 away from the active layer. The LED device is further provided with an upper electrode 700, and the upper electrode 700 is in communication with the second semiconductor layer 400 through the first opening.

[0040] In different embodiments, the first opening exposes the side surface of the second semiconductor layer 400 away from the active layer 300. The first opening can be located in the middle of the second semiconductor layer 400, or on the left side or the right side. The specific position is set according to the actual situation, and the application does not limit this. The width of the portion of the upper electrode 700 exceeding the passivation layer 500 is greater than the width of the opening, forming a "T" shaped structure.

[0041] Optionally, in the embodiment, as shown in FIG. 2, a conductive layer 800 is further arranged between the second semiconductor layer 400 and the passivation layer 500. The passivation layer 500 is provided with a second opening at a portion of the passivation layer 500 located on the side surface of the conductive layer 800 away from the second semiconductor layer 400. The LED device is further provided with an upper electrode, and the upper electrode 700 is in communication with the conductive layer 800 through the second opening. The second opening exposes the side surface of the second semiconductor layer 400 away from the active layer 300. The conductive layer 800 at least covers the surface of the second semiconductor layer 400 exposed by the first opening.

[0042] The conductive layer 800 is generally a transparent conductive film, which has the advantages of high transparency, low resistance, high corrosion resistance, etc., can improve current expansion, avoid the situation of current congestion under the condition of large current injection, and realize ohmic contact with the second semiconductor while ensuring high light transmittance, thereby improving the conductive performance.

[0043] In different embodiments, the second opening can be in the middle of the conductive layer 800, or on the left side or the right side. The width of the part of the upper electrode 700 beyond the passivation layer 500 is greater than the width of the opening, forming a "T" shaped structure.

[0044] Optionally, in some embodiments, the conductive layer is an ITO conductive layer. The conductive layer is selected as an ITO conductive layer. Since ITO is a kind of metal compound with good transparent conductive performance, it has the characteristics of wide band gap, high visible light transmittance and low resistivity, so it can realize the effects of light transmission, current expansion and ohmic contact with the second semiconductor.

[0045] Optionally, in some embodiments, the passivation layer 500 is a silicon dioxide passivation layer. The passivation layer 500 is selected as a silicon dioxide passivation layer, which can slow down thermal stress, prevent surface crack propagation, etc.; can protect the LED chip, prevent other impurity atoms from being adsorbed on the surface of the chip, thereby reducing the leakage current on the LED surface; can insulate the N-P electrode to avoid short circuit during operation.

[0046] Optionally, in some embodiments, the thickness of the passivation layer is less than the thickness of the substrate layer. By reducing the "top-side" distance, the capacitance of the device on the "top-side" path is further increased, so that it is larger than the capacitance on the "top-bottom" path, thereby reducing the capacitive reactance under high frequency driving, so that the current on the path is increased, thereby more carriers are injected to realize light emission, and the turn-on voltage of the device is reduced.

[0047] Optionally, in some embodiments, the side electrode 600 covers the surface of the passivation layer 500 away from the epitaxial layer side in a full-enclosing manner. At this time, a side electrode is formed. When the side electrode is connected to a low potential (such as ground), a "top-side" path is formed. Under the action of the electromagnetic field, the carrier transmission process may be deflected (compared with a purely vertical electric field), so that the transport distance of the carrier in the active layer is lengthened, the recombination efficiency is improved, thereby improving the light emission intensity of the device and enhancing the light emission effect of the device.

[0048] Optionally, in some embodiments, the side electrode 600 covers the surface of the opposite two sides of the passivation layer 500 away from the epitaxial layer side. At this time, two side electrodes are formed. When the two side electrodes are connected to a low potential (for example, ground), two "top-side" paths are formed. Under the action of the electromagnetic field, the carrier transmission process may be deflected (compared to a pure vertical electric field), so that the carrier transport distance in the active layer is longer than in the case of a single side electrode, and the recombination efficiency is higher, thereby better improving the device light intensity and enhancing the device light effect.

[0049] Optionally, in some embodiments, the passivation layer 500 also covers the surface of the planar part of the first semiconductor layer 200 away from the substrate layer 100 side that is not covered by the epitaxial layer.

[0050] Optionally, in some embodiments, the side electrode 600 also extends and partially covers the surface of the passivation layer 500 away from the second semiconductor layer 400 side, and extends and covers the surface of the passivation layer 500 away from the planar part of the first semiconductor layer 200 side.

[0051] By extending and partially covering the surface of the passivation layer 500 away from the second semiconductor layer 400 side and extending and covering the surface of the passivation layer 500 away from the planar part of the first semiconductor layer 200 side through the side electrode 600, the process flow can be simplified, and the probe needle can be easily poked to apply an alternating signal for testing. At the same time, the side electrode 600 can be externally connected to the outside of the device through a wire or other conductive structure, so as to facilitate the side electrode 600 to be connected to a low potential (for example, ground).

[0052] In one embodiment, as shown in FIG. 3, the side electrode 600 fully surrounds the surface of the passivation layer 500 away from the epitaxial layer side. The side electrode 600 extends and partially covers the entire surface of the passivation layer 500 away from the second semiconductor layer 400 side, and externally connects a side electrode piece to the outside of the device. Through the externally connected side electrode piece, the carrier input may be deflected under the action of the electromagnetic field, thereby improving the recombination efficiency and thus improving the device light intensity and enhancing the device light effect.

[0053] In another embodiment, as shown in FIG. 4, the side electrode 600 covers the surfaces of the opposite two sides of the passivation layer 500 facing away from the side of the epitaxial layer, the side electrode 600 extends and partially covers the opposite two sides of the passivation layer 500 facing away from the side of the second semiconductor layer 400, and two side electrode pieces are externally connected to the device. By separating the two side electrodes into two sides, an alternating signal (single-ended or differential) can be introduced. Under the action of the electromagnetic field, the conductivity of the device material changes, improving current injection. At the same time, under the action of the electromagnetic field, the probability of carrier input deflection is higher, further improving the recombination efficiency, thereby better improving the luminous intensity of the device and enhancing the light-emitting effect of the device.

[0054] Optionally, in some embodiments, the first semiconductor layer 200 is n-type GaN, and the second semiconductor layer 400 is P-type GaN. In addition, the first semiconductor layer 200 can also be p-type GaN, and the second semiconductor layer 400 is n-type GaN.

[0055] In the present embodiment, the materials of the side electrode 600 and the upper electrode 700 are metals, which can be gold (Au), silver (Ag), copper (Cu), titanium (Ti), nickel (Ni), tungsten (W), platinum (Pt), etc. The present embodiment does not limit the materials. The passivation layer 500 can be one or a combination of several of aluminum oxide (Al2O3), hafnium oxide (HfO2), silicon dioxide (SiO2), silicon nitride (Si3N4), or aluminum nitride (AlN). Preferably, the passivation layer 500 is a silicon dioxide passivation layer.

[0056] Embodiment 2

[0057] Referring to FIG. 5, the present application also provides a manufacturing method of an AC-driven LED device for manufacturing the LED device of Embodiment 1. The method comprises the following steps:

[0058] S201, providing a substrate layer;

[0059] S202, forming a first semiconductor layer on the surface of the substrate layer, the first semiconductor layer comprising a planar portion and a raised portion on the surface of the planar portion facing away from the substrate layer;

[0060] S203, forming an active layer on the surface of the raised portion of the first semiconductor layer facing away from the substrate layer;

[0061] S204, forming a second semiconductor layer on the surface of the active layer facing away from the first semiconductor layer, the second semiconductor layer being opposite in conductivity type to the first semiconductor layer;

[0062] S205, forming a passivation layer on the surface of the second semiconductor layer away from the active layer and covering the side of the epitaxial layer, the epitaxial layer being the protruding part of the first semiconductor layer, the active layer and the second semiconductor layer;

[0063] S206, forming a side electrode on the surface of the passivation layer away from the side of the epitaxial layer.

[0064] Optionally, in some embodiments, the manufacturing method of the alternating current driven LED device comprises the following steps: providing a substrate layer; epitaxially growing a first semiconductor layer, an active layer and a second semiconductor layer on the surface of the substrate layer in sequence, the first semiconductor layer comprising a planar part and a protruding part on the surface of the planar part away from the substrate layer; depositing a substrate layer on the surface of the second semiconductor layer away from the active layer, extending and covering the side of the epitaxial layer, the epitaxial layer being the protruding part of the first semiconductor layer, the active layer and the second semiconductor layer; then etching the part of the passivation layer on the surface of the second semiconductor layer away from the active layer to form a first opening, forming an upper electrode in the first opening, the upper electrode being in communication with the second semiconductor layer through the first opening; and finally forming a side electrode on the surface of the passivation layer away from the side of the epitaxial layer.

[0065] The alternating current driven LED device provided by the present application can be prepared by the preparation method of the alternating current driven LED device provided by the present application. The LED device will generate a certain inclination angle in the etching process. The inclination angle naturally formed on the side of the epitaxial layer in the deposition and etching process is utilized to further deposit the passivation layer and the side electrode. By adding the side electrode, when the side electrode is connected to a low potential (for example, ground), a "top-side" path is formed. Since the substrate layer is missing, the capacitance on the "top-side" path is larger than that on the "top-bottom" path. Therefore, the capacitive reactance under high-frequency driving is smaller, so that the current on the path is increased, thereby causing more carriers to be injected to realize light emission and reduce the turn-on voltage. At the same time, the low potential of the side electrode will cause the carriers to be deflected during the transmission process (compared to a pure vertical electric field), so that the transportation distance of the carriers in the active layer is lengthened and the recombination probability is increased, thereby improving the light emission intensity of the device. In addition, under the influence of high-frequency electromagnetic waves, the electrical conductivity of the semiconductor material will also be affected, which will affect the overall impedance of the device. By adjusting the frequency and amplitude of the electromagnetic field introduced into the device, the current injection under constant voltage conditions can be improved, the light emission intensity of the device can be improved, and the light emission effect of the device can be enhanced. Therefore, the alternating current driven LED device provided by the present application can effectively reduce the turn-on voltage of the LED device under alternating current driving, while improving the injected current, improving the light emission intensity of the device, and further enhancing the light emission effect of the device.

[0066] Obviously, the above-mentioned embodiments are only examples for clearly illustrating the present application, but not limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and also impossible to enumerate all the embodiments. The obvious changes or variations derived from the above description are still within the protection scope of the present application.

Claims

1. An AC driven LED device, characterized in that, comprising: a substrate layer; a first semiconductor layer on a surface of the substrate layer, the first semiconductor layer comprising a planar portion and a raised portion on a surface of the planar portion away from the substrate layer; an active layer on a surface of the raised portion of the first semiconductor layer away from the substrate layer; a second semiconductor layer on a surface of the active layer away from the first semiconductor layer, the second semiconductor layer being opposite in conductivity type to the first semiconductor layer, wherein the top second semiconductor layer and the bottom substrate layer are adapted to be connected to an alternating current electrode respectively, the raised portion of the first semiconductor layer, the active layer and the second semiconductor layer constituting an epitaxial layer of the LED device; a passivation layer on a surface of the second semiconductor layer away from the active layer and covering side portions of the epitaxial layer; a side electrode on a surface of the passivation layer away from the side portions of the epitaxial layer.

2. The alternating current driven LED device of claim 1, wherein: a portion of the passivation layer on the surface of the second semiconductor layer away from the active layer is provided with a first opening, and the LED device is further provided with an upper electrode, the upper electrode being in communication with the second semiconductor layer through the first opening.

3. The alternating current driven LED device of claim 1, wherein: a conductive layer is further provided between the second semiconductor layer and the passivation layer, a portion of the passivation layer on a surface of the conductive layer away from the second semiconductor layer is provided with a second opening, and the LED device is further provided with an upper electrode, the upper electrode being in communication with the conductive layer through the second opening.

4. The alternating current driven LED device of claim 3, wherein: the conductive layer is an ITO conductive layer, and the passivation layer is a silicon dioxide passivation layer.

5. The AC-driven LED device of claim 1, wherein the thickness of the passivation layer is less than the thickness of the substrate layer.

6. The alternating current driven LED device of claim 1, wherein: the side electrode fully covers the surface of the passivation layer away from the side portions of the epitaxial layer.

7. The alternating current driven LED device of claim 1, wherein: the side electrode covers the surfaces of opposite two sides of the passivation layer away from the side portions of the epitaxial layer.

8. The alternating current driven LED device of claim 6 or 7, wherein: the passivation layer further covers a portion of the planar portion of the first semiconductor layer away from the substrate layer which is not covered by the epitaxial layer.

9. The alternating current driven LED device of claim 8, wherein: the side electrode further extends and partially covers the surface of the passivation layer away from the second semiconductor layer, and extends and covers the surface of the passivation layer away from the planar portion of the first semiconductor layer.

10. A method of manufacturing an AC driven LED device, characterized by comprising the steps of: providing a substrate layer; forming a first semiconductor layer on a surface of the substrate layer, the first semiconductor layer comprising a planar portion and a raised portion on a surface of the planar portion away from the substrate layer; forming an active layer on a surface of the convex portion of the first semiconductor layer on a side opposite to the substrate layer; forming a second semiconductor layer on a surface of the active layer on a side opposite to the first semiconductor layer, the second semiconductor layer having a conductivity type opposite to that of the first semiconductor layer; forming a passivation layer on a surface of the second semiconductor layer on a side opposite to the active layer, and covering side portions of an epitaxial layer, the epitaxial layer being the convex portion of the first semiconductor layer, the active layer, and the second semiconductor layer; forming a side electrode on a surface of the passivation layer on a side opposite to the side portions of the epitaxial layer.

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