A display device using a flexible transparent substrate and its fabrication method

Abstract

This invention discloses a display device using a flexible transparent substrate and its fabrication method. The display device includes a flexible transparent substrate, a first metal circuit layer disposed on the top surface of the flexible transparent substrate, and a second metal circuit layer disposed on the bottom surface of the flexible transparent substrate. A connecting post penetrating the flexible transparent substrate is disposed within the flexible transparent substrate, and the first and second metal circuit layers are electrically connected based on the connecting post. A driver IC chip and an LED chip are mounted on the first metal circuit layer. The flexible transparent substrate is made of colorless transparent polyimide. The display device of this invention uses a flexible transparent substrate made of colorless transparent polyimide, resulting in higher overall transparency, better reliability, better appearance consistency, and superior display effect.

Description

Technical Field

[0001] This invention relates to the field of transparent display device technology, and in particular to a display device using a flexible transparent substrate and its fabrication method. Background Technology

[0002] In the field of transparent display device applications, in order to achieve higher transparency, more transparent display effects, and better control, it is necessary to minimize the number of connecting lines. Therefore, a solution with an integrated driver IC chip is usually adopted. However, display devices using an integrated driver IC chip are larger in size, and the driver IC chip itself is not transparent, which affects the overall transparency of the display device. At the same time, the driver IC chip is a rigid chip. If it is used in a flexible display device, it will form obvious bumps and is prone to falling off the flexible substrate, resulting in poor appearance consistency and reliability, which affects the display effect of the display device. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art. This invention provides a display device using a flexible transparent substrate and its preparation method. The flexible transparent substrate is made of colorless transparent polyimide, which has higher overall transparency, better reliability, better appearance consistency, and better display effect.

[0004] The present invention provides a display device using a flexible transparent substrate. The display device includes a flexible transparent substrate, a first metal circuit layer is disposed on the top surface of the flexible transparent substrate, a second metal circuit layer is disposed on the bottom surface of the flexible transparent substrate, and a connecting post penetrating the flexible transparent substrate is disposed inside the flexible transparent substrate. The first metal circuit layer and the second metal circuit layer are electrically connected based on the connecting post.

[0005] A driver IC chip and an LED chip are mounted on the first metal circuit layer. The driver IC chip is a flip chip, and the LED chip is a flip chip. The flexible transparent substrate is made of colorless transparent polyimide.

[0006] Furthermore, the thickness d1 of the flexible transparent substrate has a range of values ​​of 20μm≤d1≤80μm.

[0007] Furthermore, a third metal circuit layer is also provided on the top surface of the flexible transparent substrate, and the third metal circuit layer is disposed between the top surface of the flexible transparent substrate and the first metal circuit layer. A fourth metal circuit layer is also provided on the bottom surface of the flexible transparent substrate, and the fourth metal circuit layer is disposed between the bottom surface of the flexible transparent substrate and the second metal circuit layer.

[0008] Furthermore, the third metal circuit layer is a titanium metal layer, or the third metal circuit layer is a nickel metal layer; The fourth metal circuit layer is a titanium metal layer, or the fourth metal circuit layer is a nickel metal layer.

[0009] Furthermore, a fifth metal circuit layer is disposed on the surface of the first metal circuit layer; A sixth metal circuit layer is disposed on the surface of the second metal circuit layer.

[0010] Furthermore, the fifth metal circuit layer is a nickel-silver metal layer, or the fifth metal circuit layer is a tin metal layer; The sixth metal circuit layer is a nickel-silver metal layer, or the sixth metal circuit layer is a tin metal layer.

[0011] Furthermore, a molding layer is also provided on the top surface of the flexible transparent substrate, which covers the first metal circuit layer, the driver IC chip, and the LED chip.

[0012] Furthermore, the molding compound is made of epoxy resin or silicone.

[0013] Furthermore, the encapsulation layer is doped with scattering powder.

[0014] Furthermore, the driver IC chip is a flip chip, and / or the LED chip is a flip chip.

[0015] Furthermore, the thickness of the first metal circuit layer ranges from 2um to 35um.

[0016] Furthermore, the thickness of the second metal circuit layer ranges from 2um to 35um.

[0017] Furthermore, the connecting post penetrating the flexible transparent substrate is a through-hole structure with a copper metal layer plated on its inner wall, and the thickness of the copper metal layer plated on the connecting post ranges from 5μm to 18μm.

[0018] Furthermore, the thickness of the third metal circuit layer ranges from 0.2 μm to 1 μm; The thickness of the fourth metal circuit layer ranges from 0.2 μm to 1 μm.

[0019] Furthermore, when the fifth metal circuit layer is a nickel-silver metal layer, the thickness of the fifth metal circuit layer ranges from 3.5μm to 8μm, wherein the thickness of the nickel metal layer is 3μm to 6μm and the thickness of the silver metal layer is 0.5μm to 2μm. When the fifth metal circuit layer is a tin metal layer, the thickness of the fifth metal circuit layer ranges from 1μm to 15μm. When the sixth metal circuit layer is a nickel-silver metal layer, the thickness of the sixth metal circuit layer ranges from 3.5μm to 8μm, wherein the thickness of the nickel metal layer is 3μm to 6μm and the thickness of the silver metal layer is 0.5μm to 2μm. When the sixth metal circuit layer is a tin metal layer, the thickness of the sixth metal circuit layer ranges from 1μm to 15μm.

[0020] Furthermore, the thickness of the molding layer ranges from 100μm to 250μm.

[0021] Furthermore, the distance between the driver IC chip and the LED chip ranges from 40μm to 100μm.

[0022] Furthermore, red LED chips, green LED chips, and blue LED chips are mounted on the first metal circuit layer, and the center-to-center distance between any two LED chips ranges from 100μm to 180μm.

[0023] This invention also provides a method for fabricating a display device using a flexible transparent substrate. The method is used to fabricate the aforementioned display device using a flexible transparent substrate, and the method includes: A flexible transparent substrate made of colorless transparent polyimide is obtained, and a first metal circuit layer and a second metal circuit layer are deposited on the flexible transparent substrate to form connecting pillars. The driver IC chip and LED chip are die-bonded onto the first metal circuit layer; A molding layer is formed on the top surface of a flexible transparent substrate.

[0024] This invention provides a display device using a flexible transparent substrate and its fabrication method. The flexible transparent substrate, made of colorless transparent polyimide, significantly improves the overall transparency and clarity of the display device, optimizing the transmittance of the transparent display module. The colorless transparent polyimide flexible transparent substrate exhibits excellent temperature resistance and strong adhesion to the molding layer, effectively improving the device's airtightness and interlayer bonding, significantly reducing the risk of failure under high temperature and humidity conditions, resulting in superior reliability. The substrate's flexible material minimizes stress during bending and rolling, avoiding delamination and detachment issues caused by poor compatibility between rigid driver ICs and flexible substrates, thus adapting to flexible display scenarios. The substrate is thin and lightweight, resulting in a flat overall device with no obvious protrusions on the sides, leading to better appearance consistency and visual effects. Combined with flip-chip technology and an optimized metal circuit layer structure, the conductivity is stable and the light mixing effect is better, significantly improving the overall display effect and performance. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of a display device using a flexible transparent substrate in Embodiment 1 of the present invention; Figure 2 yes Figure 1 Enlarged view of point a in the middle; Figure 3 yes Figure 1 Enlarged view of point b in the middle; Figure 4 yes Figure 1 Enlarged view of point c in the middle; Figure 5 This is a front view of the display device using a flexible transparent substrate in Embodiment 1 of the present invention. Figure 6 This is a flowchart of the method for fabricating a display device using a flexible transparent substrate in Embodiment 2 of the present invention; Figure 7 This is a schematic diagram of the semi-finished structure of a display device using a flexible transparent substrate in Embodiment 2 of the present invention; Figure 8 This is a schematic diagram of the finished structure of a display device using a flexible transparent substrate in Embodiment 2 of the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In this invention, it should be understood that terms such as “comprising” or “having” are intended to indicate the presence of features, figures, steps, behaviors, components, portions or combinations thereof disclosed in this specification, and are not intended to exclude the possibility that one or more other features, figures, steps, behaviors, components, portions or combinations thereof are present or added.

[0029] It should also be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] Example 1 Embodiment 1 of the present invention provides a display device using a flexible transparent substrate. The display device includes a flexible transparent substrate, a first metal circuit layer is disposed on the top surface of the flexible transparent substrate, a second metal circuit layer is disposed on the bottom surface of the flexible transparent substrate, and a connecting post penetrating the flexible transparent substrate is disposed inside the flexible transparent substrate. The first metal circuit layer and the second metal circuit layer are electrically connected based on the connecting post. A driver IC chip and an LED chip are mounted on the first metal circuit layer. The driver IC chip is a flip chip, and the LED chip is a flip chip. The flexible transparent substrate is made of colorless transparent polyimide.

[0031] In one optional implementation of this embodiment, such as Figure 1 As shown, Figure 1 A schematic diagram of a display device using a flexible transparent substrate is shown in Embodiment 1 of the present invention. The display device includes a flexible transparent substrate 1, which is made of colorless transparent polyimide.

[0032] Specifically, colorless transparent polyimide (CPI) is a flexible polymer material with high light transmittance and low yellowing. It features high visible light transmittance, good heat resistance, dimensional stability, and excellent flexibility. It exhibits strong adhesion to metal circuit layers and encapsulating colloids, and excellent interfacial adhesion, simultaneously meeting the requirements of transparent display devices for high light transmittance, flexible adaptability, and high reliability. In this embodiment, the substrate made of colorless transparent polyimide is a flexible substrate, applicable to flexible display devices.

[0033] Furthermore, the thickness d1 of the flexible transparent substrate 1 has a range of values: 20μm≤d1≤80μm, and can be any value among 20μm, 40μm, 50μm, 60μm, and 80μm, determined according to actual design requirements.

[0034] Preferably, the thickness d1 of the flexible transparent substrate 1 is 50 μm. At this thickness, the manufacturing cost is lower and the preparation process is easier to implement.

[0035] In an optional implementation of this embodiment, a first metal circuit layer 2 is provided on the top surface of the flexible transparent substrate 1.

[0036] Specifically, such as Figure 1 and Figure 2 As shown, Figure 2 yes Figure 1The enlarged schematic diagram at point a shows that the first metal circuit layer 2 is disposed on the top surface of the flexible transparent substrate 1, and the first metal circuit layer 2 is formed by electroplating or chemical plating.

[0037] Furthermore, the first metal circuit layer 2 is a copper metal layer.

[0038] Furthermore, the thickness of the first metal circuit layer 2 is in the range of 2um-35um, preferably 10μm-18μm.

[0039] In an optional implementation of this embodiment, a second metal circuit layer 3 is provided on the bottom surface of the flexible transparent substrate 1.

[0040] Specifically, such as Figure 1 and Figure 3 As shown, Figure 3 yes Figure 1 The enlarged schematic diagram at point b shows that the second metal circuit layer 3 is disposed on the bottom surface of the flexible transparent substrate 1, and the second metal circuit layer 3 is formed by electroplating or chemical plating.

[0041] Furthermore, the second metal circuit layer 3 is a copper metal layer.

[0042] Furthermore, the thickness of the second metal circuit layer 3 ranges from 2µm to 35µm, preferably from 10µm to 18µm.

[0043] In an optional implementation of this embodiment, a connecting post 4 penetrating the flexible transparent substrate 1 is provided inside the flexible transparent substrate 1, and the first metal circuit layer 2 and the second metal circuit layer 3 are electrically connected based on the connecting post 4.

[0044] Specifically, such as Figure 1 and Figure 4 As shown, Figure 4 yes Figure 1 The enlarged schematic diagram at point c shows that the connecting post 4 is a through-hole structure with a copper metal layer plated on its inner wall. The connecting post 4 connects the first metal circuit layer 2 and the second metal circuit layer 3, and is used to electrically connect the first metal circuit layer 2 and the second metal circuit layer 3.

[0045] Furthermore, the thickness of the copper metal layer plated on the connecting post 4 ranges from 5μm to 18μm.

[0046] In an optional implementation of this embodiment, a driver IC chip 51 and an LED chip 52 are mounted on the first metal circuit layer 2, wherein the driver IC chip 51 is a flip chip and / or the LED chip 52 is a flip chip.

[0047] Specifically, in this embodiment, both the driver IC chip 51 and the LED chip 52 are flip chips.

[0048] Specifically, such as Figure 1 As shown, the driver IC chip 51 and the LED chip 52 are both mounted on the first metal circuit layer 2.

[0049] Furthermore, such as Figure 5 As shown, Figure 5 The diagram shows a front view of a display device using a flexible transparent substrate according to Embodiment 1 of the present invention. Red LED chips, green LED chips, and blue LED chips are mounted on the first metal circuit layer. That is, there are three LED chips 52, namely red LED chips, green LED chips, and blue LED chips.

[0050] Furthermore, the center-to-center distance between any two LED chips 52 can range from 100μm to 180μm.

[0051] Specifically, if the center-to-center spacing between LED chips is too small, it will affect die bonding; if it is too large, it will result in poor light mixing.

[0052] Furthermore, the red LED chip, green LED chip, and blue LED chip are arranged horizontally, with the short side of any LED chip close to the driver IC chip 51. This arrangement makes circuit layout more convenient and allows for flexible selection of common cathode or common anode solutions.

[0053] Furthermore, the arrangement order of the red LED chip, green LED chip, and blue LED chip can be set in a left-center-right position scheme as follows: red LED chip on the left, green LED chip in the center, and blue LED chip on the right, or green LED chip on the left, red LED chip in the center, and blue LED chip on the right.

[0054] Preferably, the optimal arrangement of green LED chips on the left, red LED chips in the middle, and blue LED chips on the right results in the best light mixing effect for the display device.

[0055] Furthermore, the distance between the driver IC chip 51 and the LED chip 52 is in the range of 40μm-100μm, preferably 60μm.

[0056] Specifically, the spacing between any LED chip 52 and the driver IC chip 51 ranges from 40μm to 100μm.

[0057] Furthermore, the thickness of any one of the LED chips 52 can be in the range of 40μm-80μm.

[0058] Furthermore, the thickness of any one of the driving IC chips 51 can range from 80μm to 200μm.

[0059] In one optional implementation of this embodiment, such as Figure 2 As shown, a third metal circuit layer 61 is also provided on the top surface of the flexible transparent substrate 1, and the third metal circuit layer 61 is disposed between the top surface of the flexible transparent substrate 1 and the first metal circuit layer 2.

[0060] Specifically, the third metal circuit layer 61 is a titanium metal layer or a nickel metal layer.

[0061] Furthermore, the thickness of the third metal circuit layer 61 ranges from 0.2 μm to 1 μm.

[0062] In one optional implementation of this embodiment, such as Figure 3 As shown, a fourth metal circuit layer 62 is also provided on the bottom surface of the flexible transparent substrate 1, and the fourth metal circuit layer 62 is disposed between the bottom surface of the flexible transparent substrate 1 and the second metal circuit layer 3.

[0063] Specifically, the fourth metal circuit layer 62 is a titanium metal layer or a nickel metal layer.

[0064] Furthermore, the thickness of the fourth metal circuit layer 62 ranges from 0.2 μm to 1 μm.

[0065] It should be noted that the third metal circuit layer 61 and the fourth metal circuit layer 62 are provided as bottom attachment layers and are directly bonded to the flexible transparent substrate 1. The titanium metal layer or nickel metal layer is used, which has a better bonding force with the colorless transparent polyimide flexible transparent substrate 1 than the copper metal layer, which is beneficial to improving the reliability of the display device.

[0066] In one optional implementation of this embodiment, such as Figure 2 As shown, a fifth metal circuit layer 71 is disposed on the surface of the first metal circuit layer 2.

[0067] Specifically, the fifth metal circuit layer 71 is a nickel-silver metal layer, or the fifth metal circuit layer 71 is a tin metal layer.

[0068] Furthermore, when the fifth metal circuit layer 71 is a nickel-silver metal layer, one side of the nickel metal layer is attached to the first metal circuit layer 2, while the silver metal layer is attached to the other side of the nickel metal layer that is not attached to the first metal circuit layer 2.

[0069] Furthermore, when the fifth metal circuit layer 71 is a nickel-silver metal layer, the thickness of the fifth metal circuit layer 71 ranges from 3.5μm to 8μm, wherein the thickness of the nickel metal layer is 3μm to 6μm and the thickness of the silver metal layer is 0.5μm to 2μm; when the fifth metal circuit layer 71 is a tin metal layer, the thickness of the fifth metal circuit layer 71 ranges from 1μm to 15μm.

[0070] In one optional implementation of this embodiment, such as Figure 3 As shown, a sixth metal circuit layer 72 is disposed on the surface of the second metal circuit layer 3.

[0071] Specifically, the sixth metal circuit layer 72 is a nickel-silver metal layer, or the sixth metal circuit layer 72 is a tin metal layer.

[0072] Furthermore, when the sixth metal circuit layer 72 is a nickel-silver metal layer, one side of the nickel metal layer is attached to the second metal circuit layer 3, while the silver metal layer is attached to the other side of the nickel metal layer that is not attached to the second metal circuit layer 3.

[0073] Furthermore, when the sixth metal circuit layer 72 is a nickel-silver metal layer, the thickness of the sixth metal circuit layer 72 ranges from 3.5μm to 8μm, wherein the thickness of the nickel metal layer is 3μm to 6μm and the thickness of the silver metal layer is 0.5μm to 2μm; when the sixth metal circuit layer 72 is a tin metal layer, the thickness of the sixth metal circuit layer 72 ranges from 1μm to 15μm.

[0074] It should be noted that a fifth metal circuit layer 71 and a sixth metal circuit layer 72 are provided here for die bonding of the driver IC chip 51 and the LED chip 52.

[0075] Specifically, after forming the first metal line layer 2 and the second metal line layer 3, the circuits are etched on the surfaces of the first metal line layer 2 and the second metal line layer 3 to form pads, and a fifth metal line layer 71 is plated on the surface of the pads formed on the first metal line layer 2, and a sixth metal line layer 72 is plated on the surface of the pads formed on the second metal line layer 3, for die bonding with the driver IC chip 51 and the LED chip 52.

[0076] In one optional implementation of this embodiment, such as Figure 1 As shown, a molding layer 8 is also provided on the top surface of the flexible transparent substrate 1, which covers the first metal circuit layer 2, the driver IC chip 51 and the LED chip 52.

[0077] Specifically, the molding layer 8 is made of epoxy resin or silicone.

[0078] Furthermore, the bonding force between the flexible transparent substrate 1 and the molding layer 8 is stronger than that between the traditional BT substrate and the molding layer 8, effectively improving the airtightness of the display device and enhancing its reliability.

[0079] Furthermore, the molding layer 8 is also filled in the connecting post 4 to further improve the bonding strength and airtightness.

[0080] In an optional implementation of this embodiment, the encapsulation layer 8 is doped with scattering powder.

[0081] Specifically, the molding layer 8 is doped with 1%-5% scattering powder, which effectively improves the light mixing effect.

[0082] Furthermore, the thickness of the molding layer 8 ranges from 100μm to 250μm.

[0083] Furthermore, the surface of the molding layer 8 is a frosted surface, and the roughness Ra ranges from 0.5μm to Ra to 2μm.

[0084] Furthermore, the edge of the molding layer 8 is flush with the edge of the flexible transparent substrate 1.

[0085] In summary, Embodiment 1 of this invention provides a display device using a flexible transparent substrate. The flexible transparent substrate, made of colorless transparent polyimide, significantly improves the overall transparency and clarity of the display device, optimizing the transmittance of the transparent display module. The colorless transparent polyimide flexible transparent substrate exhibits excellent temperature resistance and strong adhesion to the molding layer, effectively improving the device's airtightness and interlayer bonding, greatly reducing the risk of failure under high temperature and humidity conditions, resulting in superior reliability. The substrate is made of a flexible material, resulting in low stress during bending and rolling, avoiding delamination and detachment problems caused by poor compatibility between the rigid driver IC and the flexible substrate, thus adapting to flexible display scenarios. The substrate is thin and lightweight, resulting in a flat overall device with no obvious protrusions on the sides, leading to better appearance consistency and visual effect. Combined with flip-chip technology and an optimized metal circuit layer structure, the conductivity is stable and the light mixing effect is better, significantly improving the overall display effect and performance.

[0086] Example 2 Embodiment 2 of the present invention provides a method for fabricating a display device using a flexible transparent substrate. This method is used to fabricate the display device using a flexible transparent substrate described in Embodiment 1. The fabrication method includes: A flexible transparent substrate made of colorless transparent polyimide is obtained, and a first metal circuit layer and a second metal circuit layer are deposited on the flexible transparent substrate. Through holes are formed on a flexible transparent substrate, and copper is plated on the inner wall of the through holes to form connecting pillars; The driver IC chip and LED chip are die-bonded onto the first metal circuit layer; A molding layer is formed on the top surface of a flexible transparent substrate.

[0087] In one optional implementation of this embodiment, such as Figure 5 As shown, Figure 5 A flowchart illustrating the fabrication method of a display device using a flexible transparent substrate according to Embodiment 2 of the present invention is shown, including the following steps: S101. Obtain a flexible transparent substrate made of colorless transparent polyimide, deposit a first metal circuit layer and a second metal circuit layer on the flexible transparent substrate, and form connecting pillars. In one optional implementation of this embodiment, a flexible transparent substrate made of colorless transparent polyimide is obtained, and a first metal circuit layer is deposited on the top surface of the flexible transparent substrate by electroplating or chemical plating, and a second metal circuit layer is deposited on the bottom surface of the flexible transparent substrate.

[0088] Specifically, a full layer of metal circuitry is first deposited on the top surface of the flexible transparent substrate, and a full layer of metal circuitry is deposited on the bottom surface of the flexible transparent substrate. The first metal circuitry layer and the second metal circuitry layer are then formed by etching the circuitry.

[0089] In one optional implementation of this embodiment, before depositing the first metal circuit layer and the second metal circuit layer on the flexible transparent substrate, a third metal circuit layer needs to be deposited on the top surface of the flexible transparent substrate, and a fourth metal circuit layer needs to be deposited on the bottom surface of the flexible transparent substrate. Then, the first metal circuit layer is deposited on the third metal circuit layer, and the second metal circuit layer is deposited on the fourth metal circuit layer.

[0090] In an optional implementation of this embodiment, after forming the first metal circuit layer and the second metal circuit layer, through holes are formed in the flexible transparent substrate by drilling, and copper metal layers are plated on the inner walls of these through holes to form connecting pillars.

[0091] In an optional implementation of this embodiment, after forming the connecting post, a fifth metal circuit layer is plated on the corresponding line of the first metal circuit layer, and a sixth metal circuit layer is plated on the corresponding line of the second metal circuit layer.

[0092] Furthermore, when the fifth metal circuit layer is a nickel-silver metal layer, a nickel metal layer is first formed on the surface of the first metal circuit layer, and then a silver metal layer is formed on the surface of the nickel metal layer, thus forming the fifth metal circuit layer. Similarly, when the sixth metal circuit layer is a nickel-silver metal layer, a nickel metal layer is first formed on the surface of the second metal circuit layer, and then a silver metal layer is formed on the surface of the nickel metal layer, thus forming the sixth metal circuit layer.

[0093] like Figure 6 As shown, Figure 6 This diagram illustrates a semi-finished structure of a display device using a flexible transparent substrate according to Embodiment 2 of the present invention. After completing step S101, the device is manufactured as shown in the diagram. Figure 6 The semi-finished product shown is the basic structure of a transparent substrate excluding the driver IC chip, LED chip, and molding layer.

[0094] S102. Die-bond the driver IC chip and LED chip onto the first metal circuit layer; In an optional implementation of this embodiment, the driver IC chip and the LED chip are die-bonded onto the fifth metal line layer on the first metal line layer and electrically connected.

[0095] S103. A molding layer is formed on the top surface of the flexible transparent substrate.

[0096] In one optional implementation of this embodiment, a molding layer is formed on the top surface of the flexible transparent substrate using a molding process.

[0097] Furthermore, the through-hole penetrating the flexible transparent substrate 1 is filled with encapsulating adhesive.

[0098] like Figure 7 As shown, Figure 7 This diagram illustrates the finished structure of a display device using a flexible transparent substrate in Embodiment 2 of the present invention. After completing steps S101-S103, the device is manufactured as shown in the diagram. Figure 7 The finished product shown.

[0099] Furthermore, if a large-area flexible transparent substrate is used, and several display devices are simultaneously formed on this large-area flexible transparent substrate, then the entire display device needs to be cut into pieces. In summary, Embodiment 2 of this invention provides a display device using a flexible transparent substrate and its fabrication method. The flexible transparent substrate, made of colorless transparent polyimide, significantly improves the overall transparency and clarity of the display device, optimizing the transmittance of the transparent display module. The colorless transparent polyimide flexible transparent substrate exhibits excellent temperature resistance and strong adhesion to the molding layer, effectively improving the device's airtightness and interlayer bonding, significantly reducing the risk of failure under high temperature and humidity conditions, resulting in superior reliability. The substrate is made of a flexible material, resulting in low stress during bending and rolling, avoiding delamination and detachment problems caused by poor compatibility between the rigid driver IC and the flexible substrate, thus adapting to flexible display scenarios. The substrate is thin and lightweight, resulting in a flat overall device with no obvious protrusions on the sides, leading to better appearance consistency and visual effects. Combined with flip-chip technology and an optimized metal circuit layer structure, the conductivity is stable and the light mixing effect is better, significantly improving the overall display effect and performance.

[0100] The above provides a detailed description of a display device using a flexible transparent substrate and its fabrication method provided by the present invention. Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, which may include: read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, etc.

[0101] Furthermore, the embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A display device using a flexible transparent substrate, characterized in that, The display device includes a flexible transparent substrate, a first metal circuit layer is disposed on the top surface of the flexible transparent substrate, a second metal circuit layer is disposed on the bottom surface of the flexible transparent substrate, and a connecting post penetrating the flexible transparent substrate is disposed inside the flexible transparent substrate, and the first metal circuit layer and the second metal circuit layer are electrically connected based on the connecting post. The first metal circuit layer is on which a driver IC chip and an LED chip are mounted; The flexible transparent substrate is made of colorless transparent polyimide.

2. The display device using a flexible transparent substrate as described in claim 1, characterized in that, The thickness d1 of the flexible transparent substrate is in the range of 20μm≤d1≤80μm.

3. The display device using a flexible transparent substrate as described in claim 1, characterized in that, A third metal circuit layer is also provided on the top surface of the flexible transparent substrate, and the third metal circuit layer is disposed between the top surface of the flexible transparent substrate and the first metal circuit layer. A fourth metal circuit layer is also provided on the bottom surface of the flexible transparent substrate, and the fourth metal circuit layer is disposed between the bottom surface of the flexible transparent substrate and the second metal circuit layer.

4. The display device using a flexible transparent substrate as described in claim 3, characterized in that, The third metal circuit layer is a titanium metal layer, or the third metal circuit layer is a nickel metal layer; The fourth metal circuit layer is a titanium metal layer, or the fourth metal circuit layer is a nickel metal layer.

5. The display device using a flexible transparent substrate as described in claim 1, characterized in that, A fifth metal circuit layer is disposed on the surface of the first metal circuit layer; A sixth metal circuit layer is disposed on the surface of the second metal circuit layer.

6. The display device using a flexible transparent substrate as described in claim 5, characterized in that, The fifth metal circuit layer is a nickel-silver metal layer, or the fifth metal circuit layer is a tin metal layer; The sixth metal circuit layer is a nickel-silver metal layer, or the sixth metal circuit layer is a tin metal layer.

7. The display device using a flexible transparent substrate as described in claim 1, characterized in that, A molding layer is also provided on the top surface of the flexible transparent substrate, which covers the first metal circuit layer, the driver IC chip, and the LED chip.

8. The display device using a flexible transparent substrate as described in claim 7, characterized in that, The molding layer is made of epoxy resin or silicone.

9. The display device using a flexible transparent substrate as described in claim 7, characterized in that, The encapsulation layer contains scattering powder.

10. The display device using a flexible transparent substrate as described in claim 1, characterized in that, The driver IC chip is a flip chip, and / or the LED chip is a flip chip.

11. The display device using a flexible transparent substrate as described in claim 1, characterized in that, The thickness of the first metal circuit layer ranges from 2um to 35um.

12. The display device using a flexible transparent substrate as described in claim 1, characterized in that, The thickness of the second metal circuit layer ranges from 2um to 35um.

13. The display device using a flexible transparent substrate as described in claim 1, characterized in that, The connecting post penetrating the flexible transparent substrate is a through-hole structure with a copper metal layer plated on the inner wall. The thickness of the copper metal layer plated on the connecting post ranges from 5μm to 18μm.

14. The display device using a flexible transparent substrate as described in claim 3, characterized in that, The thickness of the third metal circuit layer ranges from 0.2 μm to 1 μm. The thickness of the fourth metal circuit layer ranges from 0.2 μm to 1 μm.

15. The display device using a flexible transparent substrate as described in claim 5, characterized in that, When the fifth metal circuit layer is a nickel-silver metal layer, the thickness of the fifth metal circuit layer ranges from 3.5μm to 8μm, wherein the thickness of the nickel metal layer is 3μm to 6μm and the thickness of the silver metal layer is 0.5μm to 2μm. When the fifth metal circuit layer is a tin metal layer, the thickness of the fifth metal circuit layer ranges from 1μm to 15μm. When the sixth metal circuit layer is a nickel-silver metal layer, the thickness of the sixth metal circuit layer ranges from 3.5μm to 8μm, wherein the thickness of the nickel metal layer is 3μm to 6μm and the thickness of the silver metal layer is 0.5μm to 2μm. When the sixth metal circuit layer is a tin metal layer, the thickness of the sixth metal circuit layer ranges from 1μm to 15μm.

16. The display device using a flexible transparent substrate as described in claim 7, characterized in that, The thickness of the molding layer ranges from 100μm to 250μm.

17. The display device using a flexible transparent substrate as described in claim 1, characterized in that, The distance between the driver IC chip and the LED chip ranges from 40μm to 100μm.

18. The display device using a flexible transparent substrate as described in claim 1, characterized in that, Red LED chips, green LED chips, and blue LED chips are mounted on the first metal circuit layer. The center-to-center distance between any two LED chips ranges from 100μm to 180μm.

19. A method for fabricating a display device using a flexible transparent substrate, characterized in that, The method for fabricating a display device using a flexible transparent substrate is used to fabricate a display device using a flexible transparent substrate as described in any one of claims 1-18, the fabrication method comprising: A flexible transparent substrate made of colorless transparent polyimide is obtained, and a first metal circuit layer and a second metal circuit layer are deposited on the flexible transparent substrate to form connecting pillars. The driver IC chip and LED chip are die-bonded onto the first metal circuit layer; A molding layer is formed on the top surface of a flexible transparent substrate.

Images