Micro-LED display panel

Abstract

The invention discloses a Micro-LED display panel. The Micro-LED display panel comprises a semiconductor layer; the first gate insulating layer covers the semiconductor layer; the first gate metal layer is arranged on the first gate insulating layer; the interlayer dielectric layer is arranged above the first gate insulating layer and covers the first gate metal layer; wherein the interlayer dielectric layer comprises a first sub-layer, a second sub-layer and a third sub-layer which are sequentially stacked in the direction away from the first gate insulating layer to close to the first gate insulating layer, the first sub-layer and the third sub-layer are made of the same material and contain hydrogen elements, the material of the first sub-layer is different from the material of the second sub-layer, and the material of the third sub-layer is different from the material of the second sub-layer. The first thickness of the first sub-layer and the second thickness of the second sub-layer are both larger than the third thickness of the third sub-layer. According to the invention, the hydrogen diffused to the semiconductor layer is increased, so that the electrical performance and long-term stability of the panel are improved.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and particularly to a Micro-LED display panel. Background Art

[0002] Micro-LED display devices are one of the common types of display devices currently. Micro-LED display devices have a wide range of applications and can be used in televisions, panels, wearable devices, augmented reality (AR) devices, virtual reality (VR) devices, in-vehicle displays, etc. A Micro-LED display panel includes a driving substrate and a plurality of micro light-emitting diodes arranged in an array and electrically connected to the driving substrate, thus forming a plurality of pixel units arranged in an array. The driving substrate provides driving current for the plurality of micro light-emitting diodes. The thin film transistors in the driving substrate of the Micro-LED display panel need to undergo a hydrogenation treatment during production. For example, low-temperature polysilicon thin film transistors undergo a hydrogenation treatment during production, which improves the electron mobility, reduces the defects of the transistors, and enhances the characteristics of the components.

[0003] Currently, the ability to supply hydrogen to the semiconductor layer in the display panel is insufficient, resulting in dark spots in the Micro-LED, which in turn affects the stability and display effect of the display panel. Summary of the Invention

[0004] In view of the above technical problems, the present invention provides a Micro-LED display panel, including:

[0005] A semiconductor layer;

[0006] A first gate insulating layer, covering above the semiconductor layer;

[0007] A first gate metal layer, disposed on the first gate insulating layer; and

[0008] An interlayer dielectric layer, disposed above the first gate insulating layer and covering the first gate metal layer;

[0009] Wherein, the interlayer dielectric layer includes a first sub-layer, a second sub-layer, and a third sub-layer sequentially stacked from a direction away from the first gate insulating layer to a direction close to the first gate insulating layer. The first sub-layer and the third sub-layer have the same material and contain hydrogen elements. The material of the first sub-layer is different from the material of the second sub-layer, and a first thickness of the first sub-layer and a second thickness of the second sub-layer are both greater than a third thickness of the third sub-layer.

[0010] In some embodiments, the material of the first sub-layer includes silicon nitride, the material of the second sub-layer includes silicon oxide, and the material of the third sub-layer includes silicon nitride.

[0011] In some embodiments, the ratio of the third thickness to the first thickness is between 0.2 and 0.55.

[0012] In some embodiments, the thickness of the third sub-layer is 900 - 2000 Å.

[0013] In some embodiments, the ratio of the third thickness to the second thickness is between 0.2 and 0.55.

[0014] In some embodiments, the hydrogen content of the first sub-layer and / or the third sub-layer is greater than the hydrogen content of the first gate insulating layer.

[0015] In some embodiments, the first gate insulating layer includes a first sub-gate insulating layer and a second sub-gate insulating layer stacked in sequence from near the interlayer dielectric layer to far from the interlayer dielectric layer. The material of the first sub-gate insulating layer includes silicon nitride, the material of the second sub-gate insulating layer includes silicon oxide, and the hydrogen content of the first sub-layer and the third sub-layer is greater than the hydrogen content of the first sub-gate insulating layer.

[0016] In some embodiments, the thickness of the first sub-gate insulating layer is much smaller than the thickness of the second sub-gate insulating layer.

[0017] In some embodiments, the ratio of the thickness of the first sub-gate insulating layer to the third thickness is between 0.1 and 0.22.

[0018] In some embodiments, the Micro-LED display panel further includes: a second gate insulating layer disposed between the interlayer dielectric layer and the first gate insulating layer; the material of the second gate insulating layer includes silicon nitride, and the thickness of the second gate insulating layer is between the first thickness and the third thickness; or the thickness of the second gate insulating layer is much smaller than the first thickness.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] In the solution provided by the present invention, by setting the interlayer dielectric layer as a three-layer structure and adding a third sub-layer structure containing hydrogen elements, the hydrogen diffused into the semiconductor layer is increased, ensuring the characteristics of the semiconductor layer. In other embodiments, even for the structure with the addition of the second gate insulating layer, the hydrogen diffused into the semiconductor layer can also be increased, realizing hydrogen activation, thereby improving the panel electrical performance and long-term stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0022] Figure 1 Structural schematic diagram of a Micro-LED display panel provided by an embodiment of the present invention;

[0023] Figure 2 Structural schematic diagram of a Micro-LED display panel provided by another embodiment of the present invention;

[0024] Wherein:

[0025] 1 - Semiconductor layer;

[0026] 2 - First gate insulating layer;

[0027] 21 - First sub-gate insulating layer;

[0028] 22 - Second sub-gate insulating layer;

[0029] 3 - First gate metal layer;

[0030] 31 - First metal electrode;

[0031] 4 - Interlayer dielectric layer;

[0032] 41 - First sub-layer;

[0033] 42 - Second sub-layer;

[0034] 43 - Third sub-layer;

[0035] 5 - Source electrode;

[0036] 6 - Drain electrode;

[0037] 7 - Buffer layer;

[0038] 8 - Glass substrate;

[0039] 9 - Second gate insulating layer;

[0040] 10 - Second gate metal layer;

[0041] 11 - Second metal electrode. Specific embodiments

[0042] The following will describe in detail the technical solutions of the present invention in combination with the accompanying drawings and specific embodiments to further understand the purpose, solutions and effects of the present invention, but it is not intended to limit the scope of protection of the appended claims of the present invention.

[0043] In the specification and the subsequent claims, certain terms are used to refer to specific components or parts. Those of ordinary skill in the art should understand that technology users or manufacturers may use different nouns or terms to refer to the same component or part. The specification and the subsequent claims do not use the difference in names as a way to distinguish components or parts, but use the difference in the functions of components or parts as the criterion for distinction. The terms "comprising" and "including" mentioned throughout the specification and the subsequent claims are open-ended terms and should be construed as "including but not limited to". In addition, the term "connected" herein includes any direct and indirect electrical connection means. Indirect electrical connection means include connection through other devices.

[0044] It should be noted that in the description of the present invention, the orientation or positional relationship or parameters indicated by terms such as "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "about", or "approximately", "substantially", "around", etc. are all based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description content, and does not indicate or imply that the device or element referred to must have a specific orientation, a specific size, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0045] Refer to Figure 1 , Figure 1 which is a schematic structural diagram of a Micro-LED display panel provided by an embodiment of the present invention. An embodiment of the present invention provides a Micro-LED display panel, including: a semiconductor layer 1, a first gate insulating layer 2, a first gate metal layer 3, and an interlayer dielectric layer 4; the first gate insulating layer 2 covers the semiconductor layer 1; the first gate metal layer 3 is disposed on the first gate insulating layer 2; the interlayer dielectric layer 4 is disposed above the first gate insulating layer 2 and covers the first gate metal layer 3; wherein, the interlayer dielectric layer 4 includes a first sub-layer 41, a second sub-layer 42, and a third sub-layer 43 sequentially stacked from a direction away from the first gate insulating layer 2 to a direction close to the first gate insulating layer 2. The first sub-layer 41 and the third sub-layer 43 have the same material and contain hydrogen elements. The material of the first sub-layer 41 is different from the material of the second sub-layer 42, and the first thickness of the first sub-layer 41 and the second thickness of the second sub-layer 42 are both greater than the third thickness of the third sub-layer 43.

[0046] In the Micro-LED display panel of the present invention, when hydrogen in the first sublayer 41 of the interlayer dielectric layer 4 diffuses into the semiconductor layer 1, the hydrogen in the first sublayer 41 needs to pass through the second sublayer 42 and part of the first gate insulating layer 2 to reach the semiconductor layer 1. Due to the combined thickness of the second sublayer 42, the first gate insulating layer 2, etc., the effect of hydrogen in the first sublayer 41 diffusing into the semiconductor layer 1 is limited. Based on this, the interlayer dielectric layer 4 is provided with a third sublayer 43 adjacent to the semiconductor layer 1. When hydrogen in the third sublayer 43 diffuses into the semiconductor layer 1, it only needs to pass through part of the first gate insulating layer 2. By the cooperation of the third sublayer 43 and the first sublayer 41, the effect of hydrogen diffusing into the semiconductor layer 1 is ensured.

[0047] In one embodiment, the Micro-LED display panel includes a plurality of pixel units arranged in an array, each pixel unit contains at least one Micro-LED and each pixel unit includes a driving thin film transistor, each driving thin film transistor includes the aforementioned semiconductor layer 1, the first gate metal layer 3, the source 5 (described later) and the drain 6 (described later), etc., and each driving thin film transistor is used to provide a driving current to the corresponding Micro-LED. By cooperating with the first sublayer 41 and the third sublayer 43, the characteristics of the driving thin film transistor of each pixel unit can be effectively improved, and the uniformity of the current provided to the corresponding Micro-LED can be ensured, which can significantly improve the dark spot problem of the Micro-LED display panel, such as increasing the yield by 10%, and improving the stability and display effect of the Micro-LED display panel. In addition, in the thickness direction of the Micro-LED, the third sublayer 43 is closer to the semiconductor layer 1, and can have a thinner thickness than the first sublayer 41 and the second sublayer 42, so as to avoid a significant impact on the overall thickness of the Micro-LED display panel, and cater to the trend of thinness.

[0048] In one embodiment, the material of the first sublayer 41 includes silicon nitride, the material of the second sublayer 42 includes silicon oxide, the material of the third sublayer 43 includes silicon nitride, and the semiconductor layer 1 can be low-temperature polysilicon. In this embodiment, the first sublayer 41 can diffuse hydrogen therein to the semiconductor layer 1, and can also play a role in blocking water vapor, the second sublayer 42 can play a role in taking into account the light transmission of the display panel, and the third sublayer 43 can play a role in enhancing hydrogen activation.

[0049] In one embodiment, the ratio of the third thickness of the third sub-layer 43 to the first thickness of the first sub-layer 41 is between 0.2 and 0.55, preferably between 0.2 and 0.3. Since the third sub-layer 43 is adjacent to the semiconductor layer 1, the efficiency of hydrogen diffusion from it into the semiconductor layer 1 is much greater than that of the first sub-layer 41. By setting the first thickness to be much greater than the third thickness, that is, the third sub-layer 43 has a thickness much smaller than that of the first sub-layer 41, while increasing hydrogen diffusion, it does not significantly affect the thickness of the Micro-LED display panel, taking into account both thinning and panel light transmission.

[0050] In one embodiment, the thickness of the third sub-layer 43 is 900 - 2000 Å, which takes into account the hydrogen activation function and can also avoid peeling off from other layers due to stress, etc.; the ratio of the third thickness to the second thickness is between 0.2 and 0.55, that is, the second thickness of the second sub-layer 42 can be comparable to the first thickness of the first sub-layer 41, so as to ensure the insulation performance of the interlayer dielectric layer 4 while taking into account panel light transmission. Specifically, in one embodiment, for example, the first thickness of the first sub-layer 41 can be 3850 Å, the second thickness of the second sub-layer 42 can be 3850 Å, and the third thickness of the third sub-layer 43 is 1000 Å. At this time, the first sub-layer 41 has a sufficient thickness, which can not only provide a certain function of hydrogen diffusion but also effectively block the erosion of water vapor to the components below it. The third sub-layer 43 uses its limited thickness to assist in hydrogen diffusion. In one embodiment, the cooperation of the first sub-layer 41 and the third sub-layer 43 improves the threshold voltage of the thin-film transistor for driving corresponding to the semiconductor layer 1 by 5%, for example, shifting to a positive bias of +0.2 V, etc. It can be seen from the current-voltage curve (IV curve) that the leakage current and the threshold voltage are shifted positively, which can prove that the cooperation of the first sub-layer 41 and the third sub-layer 43 can significantly improve the characteristics of the semiconductor layer 1.

[0051] In one embodiment, at least part of the material of the first gate insulating layer 2 can be the same as that of the first sub-layer 41 and / or the third sub-layer 43 and contains hydrogen. Further, the hydrogen content of the first sub-layer 41 and / or the third sub-layer 43 is greater than the hydrogen content of the first gate insulating layer 2. While ensuring that the hydrogen in the first sub-layer 41 and / or the third sub-layer 43 can diffuse into the semiconductor layer 1 to improve the characteristics of the semiconductor layer 1, the hydrogen content of the first gate insulating layer 2 is reasonably set to be lower than that of the first sub-layer 41 and / or the second sub-layer 43, so as to control the hydrogen content of the first gate insulating layer 2 within a preset range, block water vapor while ensuring the insulation performance of the first gate insulating layer 2, and avoid damage to the semiconductor layer 1 under high voltage.

[0052] In one embodiment, the first gate insulating layer 2 includes a first sub-gate insulating layer 21 and a second sub-gate insulating layer 22 stacked in sequence from being close to the interlayer dielectric layer 4 to being far from the interlayer dielectric layer 4. The material of the first sub-gate insulating layer 21 includes silicon nitride, and the material of the second sub-gate insulating layer 22 includes silicon oxide. The hydrogen content of the first sub-layer 41 and the third sub-layer 43 is greater than the hydrogen content of the first sub-gate insulating layer 21. Among them, the first sub-gate insulating layer 21 plays a role in blocking water vapor and can ensure its own insulation performance, and the second sub-gate insulating layer 22 plays a role in taking into account the light transmission of the display panel.

[0053] In one embodiment, the thickness of the first sub-gate insulating layer 21 is much smaller than the thickness of the second sub-gate insulating layer 22. Specifically, the ratio of the thickness of the first sub-gate insulating layer 21 to the third thickness is between 0.1 and 0.22. For example, the thickness of the first sub-gate insulating layer can be 200 Å, and the thickness of the second sub-gate insulating layer can be 950 Å.

[0054] In one embodiment, a source electrode 5 and a drain electrode 6 are further provided on the interlayer dielectric layer 4 of the Micro-LED display panel. The source electrode 5 and the drain electrode 6 sequentially pass through the interlayer dielectric layer 4 and the first gate insulating layer 2 to be connected to the semiconductor layer 1. The semiconductor layer 1, the first gate metal layer 3, the source electrode 5, and the drain electrode 6 form a driving thin-film transistor corresponding to each pixel unit.

[0055] In one embodiment, the Micro-LED display panel further includes a buffer layer 7 and a substrate 8. The buffer layer 7 is disposed below the first gate insulating layer 2, and the substrate 8 is disposed below the buffer layer 7. The substrate 8 can be a rigid substrate or a flexible substrate, such as a glass substrate, a PI substrate, etc.

[0056] See Figure 2 , Figure 2 FIG. is a schematic structural diagram of a Micro-LED display panel provided in another embodiment of the present invention. Another embodiment of the present invention provides a Micro-LED display panel. The structure of the display panel in this embodiment is similar to the display panel structure disclosed in the foregoing embodiment. In contrast, further, the Micro-LED display panel provided in this embodiment further includes a second gate insulating layer 9. The second gate insulating layer 9 is disposed between the interlayer dielectric layer 4 and the first gate insulating layer 2; the material of the second gate insulating layer 9 includes silicon nitride, and the thickness of the second gate insulating layer 9 is between the first thickness of the first sub-layer 41 and the third thickness of the third sub-layer 42, or the thickness of the second gate insulating layer 9 is much smaller than the first thickness of the first sub-layer 41. For example, the thickness of the second gate insulating layer 9 can be 1200 Å.

[0057] In one embodiment, the hydrogen content of the first sub-layer 41 and / or the third sub-layer 43 is greater than that of the second gate insulating layer 9. Since the thickness of the second gate insulating layer 9 is much smaller than that of the first sub-layer 41, the hydrogen diffusion paths in the first sub-layer 41 and the third sub-layer 43 will not be significantly increased due to the setting of the second gate insulating layer 9, and can still reach the semiconductor layer 1 smoothly.

[0058] In one embodiment, the second gate insulating layer 9 covers the first gate metal layer 3. The Micro-LED display panel further includes a second metal layer 10 disposed on the second gate insulating layer 9; the interlayer dielectric layer 4 covers the second metal layer 10. At this time, a source electrode 5 and a drain electrode 6 are further provided on the interlayer dielectric layer 4. The source electrode 5 and the drain electrode 6 sequentially pass through the interlayer dielectric layer 4, the second gate insulating layer 9, and the first gate insulating layer 2 to be further connected to the semiconductor layer 1. In one embodiment, the first gate metal layer 3 is located in the first metal layer. The first metal layer further includes a first metal electrode 31 adjacent to the first gate metal layer 3. The second metal layer 10 includes a second metal electrode 11. The first metal electrode 31 and the second metal electrode 11 are disposed opposite to each other and are insulated from each other due to the setting of the second gate insulating layer 9. Thus, the first metal electrode 31, the second metal electrode 11, and the second gate insulating layer 9 therebetween form a capacitive structure. In one embodiment, the first metal electrode 31 can be connected to the first gate metal layer 3, and the second metal electrode is connected to another potential (such as a corresponding data line) to stabilize the gate voltage of the corresponding driving thin-film transistor and assist in stable current output.

[0059] In one embodiment, the first metal layer further includes a plurality of gate lines arranged at uniform intervals in a row. The Micro-LED display panel further includes a third metal layer. The third metal layer includes a plurality of data lines arranged at uniform intervals in a column. The plurality of gate lines and the plurality of data lines cooperate to form a plurality of pixel unit regions arranged in an array. Each pixel unit region corresponds to a pixel unit. The second metal layer 10 and the third metal layer are provided on different layers. In addition to the aforementioned driving thin-film transistor, each pixel unit region is further provided with a switching thin-film transistor electrically connected to the driving thin-film transistor. Each gate line and each data line are connected to the corresponding switching thin-film transistor to provide corresponding electrical signals for each pixel unit.

[0060] As above, in the Micro-LED display panel of the present invention, by setting the interlayer dielectric layer as a three-layer structure and adding a third sub-layer structure containing hydrogen elements, the hydrogen diffused into the semiconductor layer is increased, ensuring the characteristics of the semiconductor layer. In other embodiments, even for the structure with an increased second gate insulating layer, the hydrogen diffused into the semiconductor layer can also be increased, realizing hydrogen activation, thereby improving the electrical performance and long-term stability of the panel.

[0061] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A Micro-LED display panel, characterized in that, Comprising: A semiconductor layer; A first gate insulating layer, covering the semiconductor layer; A first gate metal layer, disposed on the first gate insulating layer; And An interlayer dielectric layer, disposed above the first gate insulating layer and covering the first gate metal layer; Wherein, the interlayer dielectric layer includes a first sub-layer, a second sub-layer, and a third sub-layer stacked in sequence from a direction away from the first gate insulating layer to a direction close to the first gate insulating layer. The first sub-layer and the third sub-layer have the same material and contain hydrogen elements. The material of the first sub-layer is different from the material of the second sub-layer, and the first thickness of the first sub-layer and the second thickness of the second sub-layer are both greater than the third thickness of the third sub-layer.

2. The Micro-LED display panel according to claim 1, wherein, The material of the first sub-layer includes silicon nitride, the material of the second sub-layer includes silicon oxide, and the material of the third sub-layer includes silicon nitride.

3. The Micro-LED display panel according to claim 1 or 2, characterized in that, The ratio of the third thickness to the first thickness is between 0.2 and 0.

55.

4. The Micro-LED display panel according to claim 3, wherein: The thickness of the third sub-layer is 900 - 2000 Å.

5. The Micro-LED display panel according to claim 3, wherein, The ratio of the third thickness to the second thickness is between 0.2 and 0.

55.

6. The Micro-LED display panel according to claim 2, wherein The hydrogen content of the first sub-layer and / or the third sub-layer is greater than the hydrogen content of the first gate insulating layer.

7. The Micro-LED display panel according to claim 6, wherein, The first gate insulating layer includes a first sub-gate insulating layer and a second sub-gate insulating layer stacked in sequence from a direction close to the interlayer dielectric layer to a direction away from the interlayer dielectric layer. The material of the first sub-gate insulating layer includes silicon nitride, the material of the second sub-gate insulating layer includes silicon oxide, and the hydrogen content of the first sub-layer and the third sub-layer is greater than the hydrogen content of the first sub-gate insulating layer.

8. The Micro-LED display panel according to claim 7, wherein, The thickness of the first sub-gate insulating layer is much smaller than the thickness of the second sub-gate insulating layer.

9. The Micro-LED display panel according to claim 7, wherein The ratio of the thickness of the first sub-gate insulating layer to the third thickness is between 0.1 and 0.

22.

10. The Micro-LED display panel according to claim 1, wherein, Further comprising: A second gate insulating layer, disposed between the interlayer dielectric layer and the first gate insulating layer; the material of the second gate insulating layer includes silicon nitride, and the thickness of the second gate insulating layer is between the first thickness and the third thickness; or the thickness of the second gate insulating layer is much smaller than the first thickness.

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