Electrode structure and light-emitting chip
By employing an electrode structure with contact layers and composite layers in Micro LED chips, the problems of poor conductivity and stability are solved, achieving higher conductivity and stability, extending the lifespan of the light-emitting chip, and reducing maintenance costs.
Patent Information
- Application Number
- CN202422192352.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2025-11-18
- Estimated Expiration
- 2034-09-06
AI Technical Summary
The conductive electrodes in Micro LED chips have poor conductivity and low stability.
An electrode structure including a contact layer and a composite layer is adopted. The composite layer consists of at least two sub-composite layers stacked together. The sub-composite layer includes a first metal layer and a second metal layer. The conductivity of the first metal layer is stronger than that of the second metal layer, and the hardness of the second metal layer is stronger than that of the first metal layer. The structure of each layer is prepared by electron beam evaporation.
This improved the conductivity and stability of the electrode structure, extended the lifespan of the light-emitting chip, and reduced maintenance costs.
Smart Images
Figure CN223568007U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of semiconductor devices, and in particular to an electrode structure and a light emitting chip. BACKGROUND
[0002] Micro-Light Emitting Diode (Micro-LED) chips have advantages of low functional loss, long service life, good reliability, high brightness, and high pixels. In the manufacturing process of the Micro-LED chip, a conductive electrode is prepared as a power supply device and a conductor of the Micro-LED chip.
[0003] However, the conductive electrode in the related Micro-LED chip has poor conductivity and low stability. CONTENT OF THE UTILITY MODEL
[0004] The present application provides an electrode structure and a light emitting chip to improve the stability and conductivity of the electrode structure.
[0005] The present application provides an electrode structure, which comprises a contact layer and a composite layer, the composite layer is arranged on the contact layer, and the composite layer comprises at least two sub-composite layers arranged in layers.
[0006] The sub-composite layer comprises a first metal layer and a second metal layer, the first metal layer is located on the side of the second metal layer close to the contact layer, the conductivity of the first metal layer is greater than that of the second metal layer, and the hardness of the second metal layer is greater than that of the first metal layer.
[0007] Based on the above technical solution, the electrode structure provided by the present application is provided with a composite layer, which can make the electrode structure have better conductivity and higher stability and reliability, thereby prolonging the service life of the corresponding light emitting chip and reducing the maintenance cost.
[0008] In some possible implementation manners, the composite layer comprises three groups of the sub-composite layers, and the three groups of the sub-composite layers are arranged in layers on the contact layer in sequence.
[0009] In some possible implementation manners, the first metal layer comprises a copper-aluminum alloy layer, and the content of aluminum is 90% to 98%.
[0010] In some possible implementation manners, the thickness h1 of the first metal layer is 0.1 to 0.5 microns.
[0011] In some possible implementation manners, the second metal layer comprises a titanium metal layer, and the thickness h2 of the second metal layer is 0.1 to 0.5 microns.
[0012] In some possible implementation manners, the contact layer comprises a chromium metal layer, a thickness h3 of the contact layer is,
[0013] In some possible implementation manners, the electrode structure further comprises a third metal layer, the third metal layer is arranged on a side of the composite layer away from the contact layer, a thickness h4 of the third metal layer is,
[0014] In some possible implementation manners, the electrode structure further comprises a cladding layer, the cladding layer is arranged on a side of the third metal layer away from the composite layer, a stability of the cladding layer is superior to that of the third metal layer, and an electrical conductivity of the cladding layer is greater than that of the third metal layer.
[0015] In some possible implementation manners, the cladding layer comprises a gold metal layer, a thickness h5 of the cladding layer is,
[0016] In addition, the present application further provides a light-emitting chip comprising the electrode structure provided in each of the above embodiments. BRIEF DESCRIPTION OF DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced below, and it should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.
[0018] Figure 1 A structural schematic diagram of a light-emitting chip in some embodiments is shown;
[0019] Figure 2 A structural schematic diagram of an electrode structure in some embodiments is shown;
[0020] Figure 3 A size labeling schematic diagram of an electrode structure in some embodiments is shown.
[0021] Main element symbol explanation:
[0022] 1000-electrode structure;
[0023] 100-contact layer;
[0024] 200-composite layer; 210-sub-composite layer; 211-first metal layer; 212-second metal layer;
[0025] 300-third metal layer;
[0026] 400-cladding layer;
[0027] 2000 - Light chip body. DETAILED DESCRIPTION
[0028] Embodiments of the present application are described below in detail with reference to examples illustrated in the accompanying drawings, in which like or similar elements or components are denoted throughout by the same or similar reference numerals, and the embodiments described below are examples only for explaining the present application, and are not to be understood as limiting the present application.
[0029] In the description of the present application, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like indicate the orientation or positional relationship shown in the drawings, and are used only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0030] In addition, the terms "first", "second", etc. are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.
[0031] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or integrated; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0032] In the present application, unless specifically defined and limited otherwise, a first feature is "on", "above", or "under" a second feature can mean that the first and second features are directly in contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature can be "above", "over", and "on" the second feature, which means that the first feature is directly above or obliquely above the second feature, or only means that the first feature is horizontally higher than the second feature. The first feature can be "under", "below", and "under" the second feature, which means that the first feature is directly below or obliquely below the second feature, or only means that the first feature is horizontally lower than the second feature.
[0033] As shown in Figure 1 An electrode structure 1000 is provided in the embodiment, which can be applied to a light emitting chip. The light emitting chip can include, but is not limited to, a Light Emitting Diode (LED), a Mini-Light Emitting Diode (Mini-LED), or a Micro-LED product.
[0034] As shown in Figure 2 The electrode structure 1000 can include a contact layer 100 and a composite layer 200. The contact layer 100 can be used to realize the connection between the electrode structure 1000 and the main body 2000 of the light emitting chip. The composite layer 200 can be arranged on the contact layer 100, specifically, the composite layer 200 can be arranged on the side of the contact layer 100 away from the main body 2000 of the light emitting chip.
[0035] In the embodiment, the composite layer 200 can include at least two sub-composite layers 210 arranged in a stack. The sub-composite layer 210 can include a first metal layer 211 and a second metal layer 212. The first metal layer 211 can be located on the side of the second metal layer 212 close to the contact layer 100. In some embodiments, the electrical conductivity of the first metal layer 211 can be greater than that of the second metal layer 212, and the hardness of the second metal layer 212 can be greater than that of the first metal layer 211. The first metal layer 211 has strong electrical conductivity, which can make the electrode structure 1000 have strong electrical conductivity. In addition, the second metal layer 212 is arranged on the side of the first metal layer 211 away from the contact layer 100, that is, the second metal layer 212 covers the first metal layer 211, which can provide a corresponding protection function for the first metal layer 211, reduce the interference of air or water vapor on the first metal layer 211, prolong the service life of the first metal layer 211, and further prolong the service life of the electrode structure 1000.
[0036] In the embodiments, by arranging the composite layer 200, on one hand, the electrode structure 1000 can have strong conductivity, and on the other hand, the electrode structure 1000 can have strong structural strength, higher stability and reliability, and longer service life, thereby prolonging the service life of the corresponding light-emitting chip and reducing maintenance costs.
[0037] In some embodiments, each layer structure of the electrode structure 1000 can be made by a physical vapor deposition process such as an electron beam evaporation process. For example, the light-emitting chip body 2000 can be placed in an electron beam evaporation machine to sequentially deposit each layer structure of the electrode structure 1000 at the corresponding position of the light-emitting chip body 2000.
[0038] In some embodiments, the contact layer 100 can include a chromium (Cr) metal layer, that is, the contact layer 100 can be made of metal chromium, which can have higher adhesion than contact layers 100 made of other materials, thereby improving the connection stability between the electrode structure 1000 and the light-emitting chip body 2000. At the same time, chromium has high hardness, as well as good stability and corrosion resistance. Thus, a stable and reliable connection relationship between the electrode structure 1000 and the light-emitting chip body 2000 can be ensured, and the smooth transmission of electrical signals can be ensured.
[0039] Specifically, when preparing the contact layer 100, the power of the electron beam evaporation machine can be increased to 1% for 30S and maintained for 20S. Then, the power of the electron beam evaporation machine can be increased to 1.5% for 10S and maintained for 20S. Finally, the power of the electron beam evaporation machine can be decreased to 0.8% for 10S, and at the same time, the shutter in the electron beam evaporation machine is opened and evaporation starts. The evaporation rate can be set to 0.2A. and continues until the film coating of the contact layer 100 is completed.
[0040] In the embodiments, the contact layer 100 is arranged to have a lower evaporation rate when preparing the contact layer 100, which can form a relatively dense film layer of the contact layer 100, thereby achieving good connection between the electrode structure 1000 and the light-emitting chip body 2000 and improving the connection stability of the electrode structure 1000 and the light-emitting chip body 2000.
[0041] In addition, in combination with Figure 3 In the embodiments, the thickness h3 of the contact layer 100 can be set to 0.1-0.5pm. On one hand, the contact layer 100 can have sufficient adhesion to ensure that the electrode structure 1000 is stably connected to the light-emitting chip body 2000. On the other hand, the contact layer 100 can reduce light absorption.
[0042] For example, in some embodiments, the thickness h3 of the contact layer 100 can be set to 0.1-0.5pm. or to any other thickness in
[0043] In some other embodiments, the contact layer 100 can also be selected as a titanium (Ti) metal layer.
[0044] As shown in Figure 2 some embodiments, the composite layer 200 can include three groups of sub-composite layers 210. The three groups of sub-composite layers 210 can be sequentially stacked on the same side of the contact layer 100, i.e., the side of the contact layer 100 away from the light-emitting chip body 2000.
[0045] In some other embodiments, the composite layer 200 can also include one group, two groups, or five groups of sub-composite layers 210.
[0046] In some embodiments, the first metal layer 211 can be selected as an aluminum-copper alloy (AlCu) layer, i.e., the first metal layer 211 can be made of aluminum-copper alloy. Specifically, when preparing the first metal layer 211, the power of the electron beam evaporation machine can be increased to 30% for 30S and maintained for 20S. Then, the power of the electron beam evaporation machine can be increased to 45% for 10S and maintained for 20S. After that, the power of the electron beam evaporation machine can be reduced to 25% for 10S, while the internal shutter of the electron beam evaporation machine is opened and the evaporation starts, and the evaporation rate can be set to and continue until the first metal layer 211 is plated.
[0047] In combination with Figure 3 some embodiments, the thickness h1 of the first metal layer 211 can be set to On the one hand, it can ensure good electrical conductivity. On the other hand, it can ensure that the second metal layer 212 can completely cover the first metal layer 211, so as to provide protection for the first metal layer 211, improve the overall stability and reliability of the electrode structure 1000, and prolong the service life of the electrode structure 1000. Exemplarily, the thickness h1 of the first metal layer 211 can be set to
[0048] or any other thickness in 1500 to
[0049] In addition, the proportion of aluminum in the first metal layer 211 can be set to 90% to 98%. On the one hand, the first metal layer 211 can have a softer texture, reducing the probability of breaking. On the other hand, the first metal layer 211 can have stronger electrical conductivity, improving the electrical conductivity of the electrode structure 1000. At the same time, the first metal layer 211 can be used as a reflection layer, so that the light generated by the light-emitting chip body 2000 is directed to its light-emitting side as much as possible, improving the display effect of the light-emitting chip. For example, in some embodiments, the proportion of aluminum in the first metal layer 211 can be set to 90%, 92%, 95%, 98%, or any other proportion in the range of 90% to 98%.
[0050] In the embodiment, the first metal layer 211 is made of a copper-aluminum alloy layer, which has good thermal conductivity and low cost, thereby reducing the cost of the electrode structure 1000.
[0051] In some embodiments, the second metal layer 212 can include a titanium (Ti) metal layer, that is, the second metal layer 212 can be made of titanium metal, which has strong hardness to provide protection for the first metal layer 211. Specifically, when preparing the second metal layer 212, the power of the electron beam evaporation machine can first be increased to 15% for 30S and maintained for 20S. Then, the power of the electron beam evaporation machine is increased to 20% for 10S and maintained for 20S. Finally, the power of the electron beam evaporation machine is reduced to 18% for 10S, and the shutter inside the electron beam evaporation machine is opened to start evaporation, and the evaporation rate is set to 0.5A. until the second metal layer 212 is plated.
[0052] In the embodiment, titanium has high hardness, that is, the second metal layer 212 has higher hardness and corrosion resistance than the first metal layer 211, so that the second metal layer 212 can provide corresponding protection for the first metal layer 211, reducing the possibility of oxidation of the first metal layer 211. In addition, the second metal layer 212 will have a large stress under long-term high temperature, and the first metal layer 211 has a soft texture, which can absorb the stress of the second metal layer 212, thereby reducing the stress in the electrode structure 1000 and reducing the occurrence of stress concentration in the electrode structure 1000. It can be understood that the first metal layer 211 and the second metal layer 212 can complement each other to improve the overall electrical conductivity, stability, and reliability of the electrode structure 1000.
[0053] In some embodiments, the thickness h2 of the second metal layer 212 can be set to On one hand, the first metal layer 211 can be provided with more comprehensive coating, providing the first metal layer 211 with better protection function and reducing the possibility of oxidation and corrosion of the first metal layer 211. On the other hand, the stress release of the second metal layer 212 can be reduced, reducing the probability of the lower second metal layer 212 cracking the upper first metal layer 211, and thus, the service life of the electrode structure 1000 can also be prolonged. Exemplarily, the thickness h2 of the second metal layer 212 can be set to, or to any other thickness.
[0054] In the embodiment, the three groups of sub-composite layers 210 can be prepared in the same way, and the structure of each sub-composite layer 210 can be set to be the same.
[0055] As shown in Figure 2 , the electrode structure 1000 further includes a third metal layer 300, which is disposed on the side of the composite layer 200 away from the contact layer 100.
[0056] In some embodiments, the third metal layer 300 can include a nickel (Ni) metal layer, i.e., the third metal layer 300 can be made of nickel, which can have strong ductility and provide protection for the composite layer 200. When preparing the third metal layer 300, the power of the electron beam evaporation machine can first be increased to 15% for 30S and maintained for 20S. Then, the power of the electron beam evaporation machine is increased to 20% for 10S and maintained for 20S. Finally, the power of the electron beam evaporation machine is reduced to 15% for 10S, and the baffle inside the electron beam evaporation machine is turned on to start evaporation, and the evaporation rate is set to until the third metal layer 300 is plated.
[0057] Further combined with Figure 3 , in some embodiments, the thickness h4 of the third metal layer 300 can be set to, On one hand, the composite layer 200 can be provided with good protection function and reduced influence of external factors. On the other hand, the absorption of light can be reduced to ensure that as much light as possible generated by the light-emitting chip body 2000 is transmitted to the light-emitting side thereof. Exemplarily, in some embodiments, the thickness h4 of the third metal layer 300 can be set to, or to any other thickness.
[0058] As shown in Figure 2As shown, the electrode structure 1000 further comprises a cladding layer 400, which can be arranged on the side of the third metal layer 300 away from the composite layer 200. In some embodiments, the cladding layer 400 can have both electrical conductivity and stability greater than the third metal layer 300. On the one hand, the cladding layer 400 can provide corresponding protection for the electrode structure 1000. On the other hand, the electrode structure 1000 can be well connected with other electrical elements, so that the electrical signal can be quickly and smoothly transmitted, and the current injection can be facilitated.
[0059] In some embodiments, the cladding layer 400 can be made of a gold (Au) metal layer, i.e., the cladding layer 400 can be made of gold, which can have good electrical conductivity, ductility and stability. In the preparation of the cladding layer 400, the power of the electron beam evaporation machine can first be increased to 15% for 30S and maintained for 20S. Then the power of the electron beam evaporation machine is increased to 20% for 10S and maintained for 20S. Finally, the power of the electron beam evaporation machine is reduced to 12% for 10S, and the shutter inside the electron beam evaporation machine is opened to start evaporation, and the evaporation rate is set to 0.5A. until the cladding layer 400 is plated.
[0060] In addition, in combination with Figure 3 In some embodiments, the thickness h5 of the cladding layer 400 can be set to 0.1-1.0pm, 0.1-0.5pm, 0.5-1.0pm, 0.1-0.2pm, 0.2-0.3pm, 0.3-0.4pm, 0.4-0.5pm, 0.5-0.6pm, 0.6-0.7pm, 0.7-0.8pm, 0.8-0.9pm, 0.9-1.0pm, 0.1pm, 0.2pm, 0.3pm, 0.4pm, 0.5pm, 0.6pm, 0.7pm, 0.8pm, 0.9pm, or 1.0pm. In some embodiments, the thickness h5 of the cladding layer 400 can be set to 0.1-1.0pm, 0.1-0.5pm, 0.5-1.0pm, 0.1-0.2pm, 0.2-0.3pm, 0.3-0.4pm, 0.4-0.5pm, 0.5-0.6pm, 0.6-0.7pm, 0.7-0.8pm, 0.8-0.9pm, 0.9-1.0pm, 0.1pm, 0.2pm, 0.3pm, 0.4pm, 0.5pm, 0.6pm, 0.7pm, 0.8pm, 0.9pm, or 1.0pm.
[0061] or to any other thickness.
[0062] In some embodiments, the electrode structure 1000 can be used in a light-emitting chip. In some embodiments, the light-emitting chip can comprise a light-emitting chip body 2000 and the electrode structure 1000 provided in the embodiments. The light-emitting chip can include, but is not limited to, LED, Mini-LED or Micro-LED products, etc.
[0063] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.
[0064] Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and are not to be construed as limiting the present application, and the person skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.
Claims
1. An electrode structure, characterized in that, It includes a contact layer and a composite layer, wherein the composite layer is disposed on the contact layer, and the composite layer includes at least two sub-composite layers stacked together. The sub-composite layer includes a first metal layer and a second metal layer. The first metal layer is located on the side of the second metal layer that is close to the contact layer. The conductivity of the first metal layer is greater than that of the second metal layer, and the hardness of the second metal layer is greater than that of the first metal layer.
2. The electrode structure according to claim 1, characterized in that, The composite layer includes three sets of sub-composite layers, which are sequentially stacked on the contact layer.
3. The electrode structure according to claim 1, characterized in that, The thickness h1 of the first metal layer is 1500Å≤h1≤4500Å.
4. The electrode structure according to any one of claims 1 to 3, characterized in that, The second metal layer includes a titanium metal layer, and the thickness h2 of the second metal layer is 500 Å ≤ h2 ≤ 1500 Å.
5. The electrode structure according to claim 1, characterized in that, The contact layer includes a chromium metal layer, and the thickness h3 of the contact layer is 25Å≤h3≤35Å.
6. The electrode structure according to claim 1, characterized in that, The electrode structure further includes a third metal layer, which is disposed on the side of the composite layer away from the contact layer, and the thickness h4 of the third metal layer is 200Å≤h4≤600Å.
7. The electrode structure according to claim 6, characterized in that, The electrode structure further includes a coating layer, which is disposed on the side of the third metal layer away from the composite layer. The stability of the coating layer is better than that of the third metal layer, and the conductivity of the coating layer is greater than that of the third metal layer.
8. The electrode structure according to claim 7, characterized in that, The cladding layer includes a gold metal layer, and the thickness h5 of the cladding layer is 4000Å≤h5≤8000Å.
9. A light-emitting chip, characterized in that, Includes the electrode structure as described in any one of claims 1 to 8.