CN115911218A - Micro light emitting diode display device and method of manufacturing the same - Google Patents

Abstract

The invention discloses a micro light emitting diode display device and a manufacturing method thereof. The micro light emitting diode display device comprises a circuit substrate, a pixel structure layer, a support structure, a connecting layer and a protective layer. The circuit substrate has an upper surface. The pixel structure layer is arranged on the upper surface of the circuit substrate and provided with a plurality of miniature light-emitting diode units which are arranged at intervals, the miniature light-emitting diode units face the upper surface and are respectively electrically connected with the circuit substrate, and the pixel structure layer is also provided with a side surface. The supporting structure is arranged on the upper surface of the circuit substrate, extends from the upper surface to the pixel structure layer and is connected with the side surface, protrudes out of the surface of the pixel structure layer far away from the circuit substrate, and forms an accommodating space with the surface of the pixel structure layer. The connecting layer is arranged in the accommodating space. The protective layer is arranged on the connecting layer.

Description

Micro light emitting diode display device and method of manufacturing the same

Technical Field

The present invention relates to a display device, and more particularly, to a micro light emitting diode display device and a method for manufacturing the same.

Background

Micro light emitting diodes (Micro LEDs) are one of the best technologies seen when the world is focusing on future display technologies. In brief, a micro Light Emitting Diode (LED) is a technology for miniaturizing and matrixing LEDs, and millions or tens of millions of grains smaller than 100 micrometers (μm) and thinner than one hair are arranged and placed on a substrate. Compared with the existing OLED display technology, the micro-LED is also self-luminous, but can solve the most fatal branding problem of the OLED due to different used materials, and has the advantages of low power consumption, high contrast, wide color gamut, high brightness, small volume, thinness, energy conservation and the like. Therefore, various global manufacturers strive to invest in the research and development of the micro-led display technology.

In the micro led display device, since the light emitting layer of the micro led is easily damaged by moisture or foreign matter, in order to prevent the light emitting layer from being damaged by the moisture or foreign matter, a protection member having a buffering or waterproof function is generally provided to protect the micro led display device from moisture or foreign matter, thereby improving the life of the micro led display device.

It is one of the issues that has been regarded in the industry to provide a micro led display device that can prevent the invasion of moisture or foreign matter to destroy its characteristics, and further improve the service life of the micro led display device.

Disclosure of Invention

In view of the above-mentioned problems, it is an object of the present invention to provide a micro light emitting diode display device and a method for manufacturing the same, which can prevent the characteristics of the micro light emitting diode display device from being damaged by the intrusion of moisture or foreign substances, and further improve the service life of the micro light emitting diode display device.

To achieve the above objective, a micro led display device according to the present invention includes a circuit substrate, a pixel structure layer, a supporting structure, a connecting layer, and a passivation layer. The circuit substrate has an upper surface. The pixel structure layer is arranged on the upper surface of the circuit substrate, the pixel structure layer is provided with a plurality of micro light-emitting diode units which are arranged at intervals, the micro light-emitting diode units face the upper surface and are respectively and electrically connected with the circuit substrate, and the pixel structure layer is also provided with a side surface. The supporting structure is arranged on the upper surface of the circuit substrate, extends from the upper surface to the pixel structure layer and is connected with the side surface, protrudes out of the surface of the pixel structure layer far away from the circuit substrate and forms an accommodating space with the surface of the pixel structure layer. The connecting layer is arranged in the accommodating space. The protective layer is arranged on the connecting layer.

To achieve the above object, a method for manufacturing a micro light emitting diode display device according to the present invention comprises: providing a circuit substrate and a temporary substrate, wherein the circuit substrate is provided with an upper surface, the temporary substrate comprises a carrier plate, a bonding layer and a pixel structure layer, the pixel structure layer is arranged on the carrier plate through the bonding layer, and the pixel structure layer is provided with a plurality of micro light-emitting diode units which are arranged at intervals; making the micro light-emitting diode units of the pixel structure layer face the upper surface and electrically connected with the circuit substrate respectively; forming a supporting structure on the upper surface of the circuit substrate, extending from the upper surface to the side surface of the pixel structure layer, and connecting the supporting structure with the pixel structure layer, the bonding layer and the carrier plate; removing the carrier plate and the junction layer to expose the surface of the pixel structure layer, wherein the support structure protrudes out of the surface of the pixel structure layer far away from the circuit substrate and forms an accommodating space with the surface of the pixel structure layer; forming a connecting layer in the accommodating space; and arranging the protective layer on the connecting layer to connect the protective layer with the pixel structure layer through the connecting layer.

As mentioned above, in the micro led display device and the method for manufacturing the same of the present invention, the pixel structure layer is disposed on the upper surface of the circuit substrate, and has a plurality of micro led units disposed at intervals, and the micro led units face the upper surface and are electrically connected to the circuit substrate respectively; the supporting structure is arranged on the upper surface of the circuit substrate, extends from the upper surface to the pixel structure layer and is connected with the side surface of the pixel structure layer, protrudes out of the surface of the pixel structure layer far away from the circuit substrate and forms an accommodating space with the surface of the pixel structure layer; the connecting layer is arranged in the accommodating space; and the protective layer is arranged on the connecting layer, so that the micro light-emitting diode display equipment can prevent the characteristics of the micro light-emitting diode display equipment from being damaged by the invasion of water vapor or foreign matters, and the service life of the micro light-emitting diode display equipment is further prolonged.

Drawings

Fig. 1A is a schematic diagram of a micro led display device according to an embodiment of the invention.

Fig. 1B is a schematic cross-sectional view of a micro led display device according to an embodiment of the invention.

Fig. 2A to fig. 2E are schematic diagrams of a micro led display device according to different embodiments of the present invention.

Fig. 3A to fig. 3E are schematic diagrams illustrating a manufacturing process of a micro light emitting diode display device according to an embodiment of the invention.

Detailed Description

A micro light emitting diode display device and a method of fabricating the same according to some embodiments of the present invention will be described with reference to the accompanying drawings, in which like elements are described with like reference numerals. The drawings in the following embodiments are for illustrative purposes only of the relative relationships between elements or units, and do not represent actual dimensions or proportions of the elements or units.

Fig. 1A is a schematic diagram of a micro led display device according to an embodiment of the invention, and fig. 1B is a schematic cross-sectional diagram of the micro led display device according to the embodiment of the invention.

Referring to fig. 1A and 1B, the micro led display device 1 may be an Active Matrix (Active Matrix) or Passive Matrix (Passive Matrix) micro led display, and may include a circuit substrate 11, a pixel structure layer 12, a supporting structure 13, a connection layer 14, and a protection layer 15.

The micro led display device 1 may include a plurality of pixels P arranged in a matrix of rows and columns. Wherein each pixel P comprises three Sub-pixels (Sub-pixels) arranged side by side, each Sub-pixel comprising one micro-led unit 121 (i.e. each pixel P comprises three micro-led units 121 arranged side by side). In different embodiments, the arrangement of the three sub-pixels of each pixel P may also be different; for example, two of the three sub-pixels are arranged above and below one another and are arranged side by side with one another, or in other arrangements. In different embodiments, each pixel P may also include, for example, four or more sub-pixels. Taking four sub-pixels as an example, the four sub-pixels may be arranged side by side, or arranged in a2 × 2 matrix, or other arrangement, and are not limited.

The circuit substrate 11 has a display area A1 and a non-display area A2, the display area A1 is an area for displaying images in the micro light emitting diode display device 1, i.e. an area where the pixels P (micro light emitting diode units 121) are disposed, and the non-display area A2 is located at the periphery (which may be surrounded or not surrounded) of the display area A1, and is an area where driving components (e.g. ICs) or circuits are disposed. The wiring substrate 11 also has an upper surface S1. The circuit substrate 11 is a driving substrate for driving the micro light emitting diode units 121 to emit light, and may be, for example, a complementary metal oxide semiconductor CMOS substrate, a liquid crystal on silicon LCOS substrate, a thin film transistor TFT substrate, or other circuit substrates with an operating circuit, but is not limited thereto. Note that the "thickness" or "height" mentioned below refers to the thickness or height of the upper surface S1 of the vertical wiring substrate 11; and "width" or "size" refers to the width or size of the upper surface S1 of the parallel wiring substrate 11.

The pixel structure layer 12 is disposed on the upper surface S1 of the circuit substrate 11. The pixel structure layer 12 has a plurality of micro led units 121 disposed at intervals, and the micro led units 121 face the upper surface S1 of the circuit substrate 11 and are electrically connected to the circuit substrate 11, so that the micro led units 121 are controlled (driven) to emit light through the circuit substrate 11. In the present embodiment, a plurality of concave portions U are formed on the surface of the pixel structure layer 12 facing the circuit substrate 11 to separate the micro led units 121 arranged in an array, and each micro led unit 121 can independently control light emission. In addition, the pixel structure layer 12 further has a side surface S2.

Each of the micro led units 121 of the present embodiment can provide a light source for one sub-pixel, and includes a first type semiconductor layer 121a, a light emitting layer 121b, and a second type semiconductor layer 121c, which are overlapped, wherein the light emitting layer 121b is sandwiched between the first type semiconductor layer 121a and the second type semiconductor layer 121 c. The first type semiconductor layer 121a is, for example, an N-type semiconductor, and in detail, the pixel structure layer 12 of the present embodiment includes a continuous first type semiconductor layer 121a (sharing an N-type structure), and the micro light emitting diode units 121 share the first type semiconductor layer 121a, but not limited thereto. The second-type semiconductor layer 121c is, for example, a P-type semiconductor, and the light-emitting layer 121b is, for example, a multiple quantum well MQW layer, but the invention is not limited thereto. In various embodiments, the first type semiconductor layer 121a may be a P-type semiconductor (in which case, a common P-type structure may be formed), and the second type semiconductor layer 121c may be an N-type semiconductor.

In addition, the circuit substrate 11 of the present embodiment may further include a plurality of conductive electrodes (111, 112), and the conductive electrodes are respectively disposed corresponding to the micro led units 121 of the pixel structure layer 12 (e.g., one-to-one correspondence). Here, each conductive electrode may be electrically connected to a circuit layer (not shown) of the corresponding circuit substrate 11. Therefore, the circuit substrate 11 can transmit the independently controlled electrical signals to the corresponding conductive electrodes through the circuit layer, thereby driving the corresponding micro led units 121 to emit light.

The conductive electrode of the present embodiment may include a plurality of first electrodes 111 and second electrodes 112 surrounding the micro led units 121, each of the first electrodes 111 is electrically connected to the second type semiconductor layer 121C of the corresponding micro led unit 121 through a conductive member C1, and the second electrodes 112 serve as a common electrode of the pixel structure layer 12 and are also electrically connected to the first type semiconductor layer 121a of the micro led unit 121 through a conductive member C2. It should be noted that, as can be understood by those skilled in the art, the conductive element C2 (and the second electrode 112) in fig. 1B need not be disposed around the upper surface S1 of the circuit substrate 11. The conductive members C1 and C2 may be made of, for example, but not limited to, indium, tin, copper, silver, gold, or an Alloy (e.g., a metal other than tin plus copper) of any combination of the foregoing materials, and the invention is not limited thereto. In addition, in the micro light emitting diode units 121, except for the regions contacting with the conductive members C1 and C2, the insulating layer 16 is disposed on the surface of the micro light emitting diode unit 121 facing the circuit substrate 11, and the insulating layer 16 is used to protect the structure of the micro light emitting diode unit 121. In other words, the region of the lower surface of the pixel structure layer 12 not in contact with the conductive members C1 and C2 is provided with the insulating layer 16.

The supporting structure 13 is disposed on the upper surface S1 of the circuit substrate 11, extends from the upper surface S1 to the pixel structure layer 12, and is connected to the side surface S2 of the pixel structure layer 12. Here, the supporting structure 13 protrudes from the surface S3 of the pixel structure layer 12 away from the circuit substrate 11, and forms an accommodating space S with the surface S3 of the pixel structure layer 12. The supporting structure 13 of the present embodiment is disposed in the non-display area A2 and surrounds the display area A1. Here, the supporting structure 13 protrudes from the surface S3 of the pixel structure layer 12 to form a retaining wall 131, and the retaining wall 131 and the (upper) surface S3 of the pixel structure layer 12 away from the circuit substrate 11 form an accommodating space S. In some embodiments, the support structure 13 may be made of a transparent curable insulating material, or a curable insulating material with other colors, for example, a black support structure 13 may prevent crosstalk, and if a white support structure 13 has a mirror effect, the light-emitting rate may be increased. In some embodiments, the supporting structure 13 may be an insulating glue, for example, a material including silicon gel or/and epoxy. In some embodiments, the height of the retaining wall 131 may be greater than 1300 μm (if the height is too low, the subsequently disposed connection layer 14 may be too thin to firmly connect with the protection layer 15, and the yield is reduced). In some embodiments, the width of the retaining wall 131 is larger than 10 μm (if the width is too small, it may be easy to break, and the yield may be reduced).

In addition, the micro led display device 1 of the embodiment may further include a filling layer 13a, where the filling layer 13a is an insulating layer disposed between the pixel structure layer 12 and the upper surface S1 of the circuit substrate 11, and not only provides a buffer during pressing to avoid the pixel structure layer 12 from being broken and fix the position of the micro led unit 121, but also further prevents a short circuit between the first electrode 111 and the second electrode 112. However, due to the manufacturing process, the gap between the pixel structure layer 12 and the upper surface S1 of the circuit substrate 11 may not be filled with the filling layer 13a, and therefore, in some embodiments, the filling layer 13a may have a gap (air bubble). In some embodiments, the material of the filling layer 13a may include an organic polymer material such as photoresist and ink. In some embodiments, the filling layer 13a may be an insulating glue, for example, a material including silicon gel or/and epoxy resin.

In some embodiments, the support structure 13 and the filling layer 13a may be integrally formed. In other words, an integrated structure including the supporting structure 13 and the filling layer 13a can be formed in the same process and by using the same material, such that the filling layer 13a is filled between the pixel structure layer 12 and the upper surface S1 of the circuit substrate 11, and the supporting structure 13 is disposed around the periphery of the pixel structure layer 12, contacts the side surface S2, and protrudes from the side surface S2 to form the retaining wall 131, so as to form the accommodating space S for disposing the connection layer 14.

The connection layer 14 is disposed in the accommodating space S. The material of the connection layer 14 of the present embodiment is transparent insulation, and the accommodation space S is filled with the material. In other words, the connection layer 14 is located in the accommodating space S and tightly connected to the supporting structure 13 (the retaining wall 131). Here, the supporting structure 13 (the wall 131) can define the shape and thickness of the connecting layer 14, and the height of the wall 131 is equal to the thickness of the connecting layer 14. In some embodiments, the thickness of the connection layer 14 is less than 1300 μm (if it is too thick, the excess material may overflow the retaining wall 131 to form residual glue when connecting with the protection layer 15). In addition, the smaller thickness of the connection layer 14 helps to reduce the occurrence of cross talk (crosstalk).

The protective layer 15 is disposed on the connection layer 14. Here, the top surface S5 of the connection layer 14 is flush with the top surface S4 of the support structure 13, and the connection layer 14 is located between the protection layer 15 and the pixel structure layer 12, so that the protection layer 15 can be connected to the pixel structure layer 12 through the connection layer 14. The protection layer 15 of the present embodiment is disposed (covered) on the top surface S4 of the retaining wall 131 and the top surface S5 of the connection layer 14, and the bottom surface of the protection layer 15 is directly contacted and connected with the top surface S4 of the retaining wall 131 and the top surface S5 of the connection layer 14. In addition, the size of the protection layer 15 in this embodiment is larger than the size of the connection layer 14 (i.e. the projected area of the protection layer 15 on the circuit substrate 11 is larger than the projected area of the connection layer 14 on the circuit substrate 11), and the projection of the protection layer 15 on the circuit substrate 11 is located in the projection of the connection layer 14 and the support structure 13 on the circuit substrate 11 (i.e. the projected area of the protection layer 15 on the circuit substrate 11 is equal to the projected area of the connection layer 14 and the support structure 13 on the circuit substrate 11, and the projections are completely overlapped); in other embodiments, the projection of the protection layer 15 on the circuit substrate 11 may be slightly smaller than the projection of the connection layer 14 and the support structure 13 on the circuit substrate 11 (i.e., the projection area of the protection layer 15 on the circuit substrate 11 is smaller than the projection area of the connection layer 14 and the support structure 13 on the circuit substrate 11), but the projection of the protection layer 15 on the circuit substrate 11 may be larger than the projection area of the connection layer 14 on the circuit substrate 11, so as to completely protect the micro light emitting diode unit 121 and the circuit substrate 11 from being damaged by the intrusion of moisture or foreign matters, thereby improving the service life.

In the present embodiment, the material of the protective layer 15 is different from that of the connection layer 14. In some embodiments, the protection layer 15 is made of a transparent material, and can be a rigid board, a flexible board or a rigid-flexible board, such as a glass substrate, a polyimide PI substrate, or a film layer combined with a composite material at least including the foregoing materials. The protective layer 15 of the present embodiment is a glass substrate. The connection layer 14 includes, for example, an organic polymer material such as, but not limited to, a resin. In some embodiments, the thickness of the protective layer 15 may be greater than 100 μm. In addition, the Young's modulus (also called elastic modulus) of the protection layer 15 of the present embodiment is larger than that of the support structure 13, and the Young's modulus of the protection layer 15 is also larger than that of the connection layer 14, so that the protection layer 15 can provide better protection effect and also provide buffer when the support structure 13 and the connection layer 14 are connected.

In addition, fig. 2A to fig. 2E are schematic diagrams of a micro light emitting diode display device according to different embodiments of the present invention.

As shown in fig. 2A, the micro light emitting diode display device 1a of the present embodiment is substantially the same as the micro light emitting diode display device 1 of the previous embodiment in terms of the component composition and the connection relationship of the components. The difference is that in the micro led display device 1a of the present embodiment, the projection area of the protection layer 15 on the circuit substrate 11 is larger than the projection area of the connection layer 14 on the circuit substrate 11. In addition, the retaining wall 131 of the supporting structure 13 protruding from the surface S3 of the pixel structure layer 12 is step-shaped and at least includes a first step L1 and a second step L2, the first step L1 is disposed around the periphery of the connection layer 14, and the second step L2 is disposed on the first step L1 and around the periphery of the passivation layer 15. In detail, the first step L1 of the stepped retaining wall 131 surrounds the connection layer 14 and is connected to the side of the connection layer 14, and the second step L2 surrounds the protection layer 15 and is connected to the side of the protection layer 15. In addition, the thickness of the connection layer 14 is equal to the height of the first level L1, and the thickness of the protection layer 15 is equal to the height of the second level L2. In addition, the top surface S6 of the passivation layer 15 of the embodiment is flush with the top surface S4 of the supporting structure 13, i.e. the connection layer 14 and the passivation layer 15 are both located in the receiving space S and embedded into the receiving space S to be tightly connected with the supporting structure 13 (the retaining wall 131).

In addition, as shown in fig. 2B, the micro light emitting diode display device 1B of the present embodiment is substantially the same as the micro light emitting diode display device of the previous embodiment in terms of the component composition and the connection relationship of the components. The difference is that in the micro led display device 1b of the present embodiment, the projection area of the protection layer 15 on the circuit substrate 11 is equal to the projection area of the connection layer 14 on the circuit substrate 11. Specifically, the size of the passivation layer 15 is the same as that of the connection layer 14, the passivation layer 15 and the connection layer 14 are both located in the receiving space S and embedded in the receiving space S, and the retaining walls 131 of the supporting structure 13 are tightly connected. In addition, the side surface of the protective layer 15 of the present embodiment is flush with the side surface S2 of the connection layer 14.

In addition, as shown in fig. 2C, the micro light emitting diode display device 1C of the present embodiment is substantially the same as the micro light emitting diode display device of the previous embodiment in terms of the component composition and the connection relationship of the components. The difference is that in the micro led display device 1c of the present embodiment, the size of the protection layer 15 is smaller than that of the connection layer 14, and therefore, the projection area of the protection layer 15 on the circuit substrate 11 is smaller than that of the connection layer 14 on the circuit substrate 11. In addition, a portion of the connection layer 14 is located between the passivation layer 15 and the pixel structure layer 12, and another portion of the connection layer 14 is located between the retaining wall 131 of the supporting structure 13 and the side surface of the passivation layer 15, so that the passivation layer 15 is not in direct contact with the retaining wall 131 of the supporting structure 13, and the connection layer 14 can be more tightly connected to the retaining wall 131.

In addition, as shown in fig. 2D, the micro light emitting diode display device 1D of the present embodiment is substantially the same as the micro light emitting diode display device of the previous embodiment in terms of the component composition and the connection relationship of the components. The difference is that in the micro led display device 1d of the present embodiment, the connection layer 14 may define a plurality of separated light conversion regions 141, and each light conversion region 141 corresponds to one of the micro led units 121. The light conversion region 141 of the present embodiment is disposed to overlap with the corresponding micro light emitting diode unit 121 in a direction perpendicular to the upper surface S1. Here, each of the light conversion regions 141 is a through hole formed in the connection layer 14, and the through hole can communicate the surface S3 and the top surface S5 of the connection layer 14, so that the light emitted from the micro light emitting diode units 121 corresponding to the light conversion regions 141 can pass through the through hole (the light conversion region 141) and be emitted upward, that is, the light emitted from the micro light emitting diode units 121 can pass through the through hole.

In addition, the micro led display device 1d of the present embodiment may further include a light conversion layer 17, the light conversion layer 17 is disposed in the light conversion regions 141, and the light conversion layer 17 is used for converting the light emitting wavelength of the corresponding micro led unit 121. The light conversion layer 17 of the present embodiment includes a plurality of separated light conversion portions 171a and 171b, the light conversion portions 171a and 171b are respectively disposed in the corresponding light conversion regions 141, and one light conversion portion 171a and 171b respectively corresponds to one micro light emitting diode unit 121. Specifically, in the three sub-pixels of one pixel P, the materials of the light conversion portions 171a and 171b that convert different wavelengths of light are filled in the light conversion regions 141 of two sub-pixels, respectively. Here, the light conversion layer 17 (the light conversion parts 171a and 171 b) may include a light conversion substance, and may include, for example, quantum dots QD, a phosphorescent material, or a fluorescent material. The light conversion substance of the present embodiment is exemplified by including quantum dots. Here, quantum dots of different sizes may be excited to produce different colors of light (e.g., excitation of quantum dots of different sizes by blue light may produce red and green light). Therefore, in each of the light conversion regions 141 corresponding to the light conversion portions 171a and 171b, the light (e.g., blue light) emitted by the sub-pixels (i.e., the micro light emitting diode units 121) therein will be converted into a set color (e.g., red light and green light) by the corresponding light conversion portion (light conversion portion 171a and 171 b) and emitted. In another sub-pixel without conversion, the through hole corresponding to the light conversion layer 17 may be filled with or without a transparent adhesive.

In addition, the connection layer 14 of the micro led display device 1d of the present embodiment can be a light absorbing material, such as a black photoresist, or a reflective material, such as a white highly reflective silica gel, for absorbing or reflecting light to prevent light interference between sub-pixels.

In some embodiments, a thicker connecting layer 14 may be desirable when a thicker light-converting layer 17 (light-converting portions 171a, 171 b) is used in order to achieve higher color purity. In some embodiments, in addition to the light conversion portions 171a and 171b, a filter layer (red and green filter materials) may be further added to each light conversion region 141 to improve the color purity of the outgoing light. In addition, in different embodiments, the micro light emitting diode unit 121 may also be configured with other corresponding light conversion parts (and/or filter parts) to emit light of other colors (for example, yellow light or white light, but not limited thereto). It is understood that, in order to increase the light-emitting rate of the micro led unit 121, a reflective layer (not shown) having a light reflective material may be disposed at the periphery of the sidewall of each light conversion region 141.

In addition, as shown in fig. 2E, the micro light emitting diode display device 1E of the present embodiment is substantially the same as the micro light emitting diode display device of the previous embodiment in terms of the component composition and the connection relationship of the components. The difference is that in the micro led display device 1e of the present embodiment, a light processing layer 18 may be further included, the light processing layer 18 is disposed on the top surface S6 of the protection layer 15, and a plurality of separated light conversion regions 181 may be defined, and each light conversion region 181 corresponds to one of the sub-pixels (micro led units 121). The photo-processing layer 18 may be a light-absorbing material, such as black photoresist, or a reflective material, such as white highly reflective silica gel, for absorbing or reflecting light. In another sub-pixel (micro led unit 121) that does not need to be converted, the through hole corresponding to the photo processing layer 18 may be filled with or without a transparent adhesive.

In addition, the light conversion layer 17 of the present embodiment is disposed in the light conversion regions 181 of the transparent layer 18 and is used for converting the light emitting wavelength of the corresponding micro led units 121. As in the previous embodiment, the light conversion portions 171a and 171b of the light conversion layer 17 are respectively disposed in the corresponding light conversion regions 181, and one light conversion portion 171a and 171b respectively corresponds to one micro light emitting diode unit 121. In addition, it can be understood that a reflective layer having a light reflective material may be disposed at the sidewall periphery of each light conversion region 181 to improve the light extraction efficiency.

Fig. 3A to fig. 3E are schematic diagrams illustrating a manufacturing process of a micro led display device according to an embodiment of the invention.

The method for manufacturing the micro light emitting diode display device of the embodiment at least comprises the following steps of one to six.

As shown in fig. 3A, the first step is: providing a circuit substrate 11 and a temporary substrate 2, wherein the circuit substrate 11 has an upper surface S1, the temporary substrate 2 includes a carrier 21, a bonding layer 22 and a pixel structure layer 12, the pixel structure layer 12 is disposed on the carrier 21 through the bonding layer 22, and the pixel structure layer 12 has a plurality of micro led units 121 disposed at intervals.

The second step is: the micro led units 121 of the pixel structure layer 12 face the upper surface S1 of the circuit substrate 11 and are electrically connected to the circuit substrate 11. Here, the temporary substrate 2 is reversed to make the micro-light emitting diode units 121 face downward, so that each first electrode 111 of the circuit substrate 11 is electrically connected to the second type semiconductor layer 121C of the corresponding micro-light emitting diode unit 121 through a conductive member C1, and the second electrode 112 of the circuit substrate 11, which is a common electrode of the pixel structure layer 12, is also electrically connected to the first type semiconductor layer 121a of the micro-light emitting diode unit 121 through a conductive member C2.

As shown in fig. 3B, step three is: the supporting structure 13 is formed on the upper surface S1 of the circuit substrate 11, and extends from the upper surface S1 to the side surface S2 of the pixel structure layer 12, so that the supporting structure 13 is connected to the pixel structure layer 12, the bonding layer 22 and the carrier 21. Here, the supporting structure 13 protrudes from the side surface S2 of the pixel structure layer 12, and is connected to the side surface S2 of the pixel structure layer 12, the bonding layer 22, and the side surface of the carrier 21. However, in the third step of forming the supporting structure 13 on the upper surface S1 of the circuit substrate 11, the method may further include: the material filling the support structure 13 is disposed between the pixel structure layer 12 and the circuit substrate 11, thereby forming a filling layer 13a. Specifically, the supporting structure 13 may be formed in the same process and made of the same material to surround the periphery of the pixel structure layer 12 and contact the side S2 of the pixel structure layer 12, the bonding layer 22 and the side of the carrier 21, and in addition, the material of the supporting structure 13 is also filled between the pixel structure layer 12 and the upper surface S1 of the circuit substrate 11 to form the filling layer 13a (which may be simultaneous or non-simultaneous), so that the supporting structure 13 and the filling layer 13a are integrally formed, and the process yield and the product reliability may be increased. Of course, in different embodiments, the supporting structure 13 and the filling layer 13a may also be independent members, and the materials thereof may be the same or different, and are not limited.

Next, as shown in fig. 3C, the fourth step is: the carrier 21 and the bonding layer 22 are removed to expose the surface S3 of the pixel structure layer 12, wherein the supporting structure 13 protrudes from the surface S3 of the pixel structure layer 12 away from the circuit substrate, and forms an accommodating space S with the surface S3 of the pixel structure layer 12. Since the filling layer 13a is disposed between the pixel structure layer 12 and the circuit substrate 11, the bonding strength between the pixel structure layer 12 and the circuit substrate 11 can be increased, and the pixel structure layer 12 and the circuit substrate 11 will not be separated when the carrier 21 is removed.

In addition, the fifth step is: the connection layer 14 is formed in the accommodating space S. However, before the fifth step, as shown in fig. 3D, a thinning process may be performed to reduce the thickness of the pixel structure layer 12, and the height of the retaining wall 131 of the supporting structure 13 protruding from the surface S2 of the pixel structure layer 12 is also modified, so as to define the shape and thickness of the connecting layer 14 filled into the accommodating space S through the retaining wall 131. In some embodiments, the thickness of the first type semiconductor layer 121a of the pixel structure layer 12 may be reduced by a dry etching process, in which the height of the dam 131 is also adjusted to meet the requirement. It should be noted that the etching rate of the supporting structure 13 is different from that of the pixel structure layer 12 in this embodiment. In some embodiments, the etching rate of the supporting structure 13 is greater than that of the pixel structure layer 12, so that the height of the retaining wall 131 can be controlled while the pixel structure layer 12 is thinned, and a suitable accommodating space is obtained for completely adhering the protection layer 15. Then, as shown in fig. 3E, the fifth step is performed: the connection layer 14 is formed in the accommodating space S. The height of the retaining wall 131 of this embodiment is equal to the thickness of the connection layer 14.

Finally, as shown in fig. 3E, step six is performed: and arranging a protective layer 15 on the connecting layer 14, so that the protective layer 15 is connected with the pixel structure layer 12 through the connecting layer 14, thereby obtaining the micro light-emitting diode display device 1. In this embodiment, the young's modulus of the protective layer 15 is greater than that of the support structure 13, and the young's modulus of the protective layer 15 is also greater than that of the connection layer 14. In addition, the top surface S5 of the connection layer 14 of the present embodiment is flush with the top surface S4 of the support structure 13. In addition, the size of the protection layer 15 in this embodiment is larger than that of the connection layer 14, and the projection of the protection layer 15 on the circuit substrate 11 completely overlaps with the projection of the connection layer 14 and the support structure 13 on the circuit substrate 11.

In addition, other technical features of the manufacturing method of the micro light emitting diode display device have been described in detail in the above embodiments, and will not be further described herein.

In summary, in the micro led display device and the method for manufacturing the same of the present invention, the pixel structure layer is disposed on the upper surface of the circuit substrate, and has a plurality of micro led units disposed at intervals, and the micro led units face the upper surface and are electrically connected to the circuit substrate respectively; the supporting structure is arranged on the upper surface of the circuit substrate, extends from the upper surface to the pixel structure layer and is connected with the side surface of the pixel structure layer, protrudes out of the surface of the pixel structure layer far away from the circuit substrate and forms an accommodating space with the surface of the pixel structure layer; the connecting layer is arranged in the accommodating space; and the protective layer is arranged on the structural design of the connecting layer, so that the miniature light-emitting diode display equipment can prevent the characteristics of the miniature light-emitting diode display equipment from being damaged due to the invasion of water vapor or foreign matters, and the service life of the miniature light-emitting diode display equipment is further prolonged.

The foregoing is by way of example only, and not limiting. It is intended that all equivalent modifications or variations without departing from the spirit and scope of the present invention shall be included in the appended claims.

Claims (15)

1. A miniature light emitting diode display device comprising:

a circuit substrate having an upper surface;

the pixel structure layer is arranged on the upper surface of the circuit substrate and provided with a plurality of miniature light-emitting diode units which are arranged at intervals, face the upper surface and are respectively and electrically connected with the circuit substrate; wherein the pixel structure layer further has a side surface;

the supporting structure is arranged on the upper surface of the circuit substrate, extends from the upper surface to the pixel structure layer and is connected with the side surface of the pixel structure layer, protrudes out of the surface of the pixel structure layer far away from the circuit substrate and forms an accommodating space with the surface of the pixel structure layer;

the connecting layer is arranged in the accommodating space; and

and the protective layer is arranged on the connecting layer.

2. The micro light emitting diode display device of claim 1, wherein the circuit substrate further comprises a display region and a non-display region, the non-display region is disposed at a periphery of the display region, and the supporting structure is disposed in the non-display region.

3. The micro light emitting diode display device of claim 1, further comprising:

and the filling layer is arranged between the pixel structure layer and the upper surface of the circuit substrate.

4. The micro light-emitting diode display device of claim 3, wherein the support structure is integrally formed with the filler layer.

5. The micro light emitting diode display device of claim 3, wherein the filling layer has a void.

6. The micro led display device of claim 1, wherein the passivation layer is disposed on the supporting structure and the connection layer, and a projection of the passivation layer onto the circuit substrate is located within a projection of the connection layer and the supporting structure onto the circuit substrate.

7. The micro led display device of claim 1, wherein the supporting structure protrudes from the surface of the pixel structure layer to form a retaining wall, the retaining wall is stepped and comprises at least a first step and a second step, the first step is disposed around the periphery of the connection layer, and the second step is disposed on the first step and surrounds the periphery of the passivation layer.

8. The micro light emitting diode display device of claim 1, wherein the protection layer and the connection layer are disposed in the accommodating space.

9. The micro light emitting diode display device of claim 1, wherein a projected area of the protection layer on the circuit substrate is smaller than or equal to a projected area of the connection layer on the circuit substrate.

10. The micro light emitting diode display device of claim 9, wherein a portion of the connection layer is further located between the support structure and a side of the protective layer.

11. The micro light emitting diode display device of claim 1, wherein the protective layer has a young's modulus greater than the support structure; the protective layer has a Young's modulus greater than the tie layer.

12. A method of manufacturing a micro light emitting diode display device, comprising:

providing a circuit substrate and a temporary substrate, wherein the circuit substrate is provided with an upper surface and comprises a carrier plate, a bonding layer and a pixel structure layer, the pixel structure layer is arranged on the carrier plate through the bonding layer, and the pixel structure layer is provided with a plurality of micro light-emitting diode units which are arranged at intervals;

the micro light-emitting diode units of the pixel structure layer face the upper surface and are electrically connected with the circuit substrate respectively;

forming a supporting structure on the upper surface of the circuit substrate, extending from the upper surface to the side surface of the pixel structure layer, and connecting the supporting structure with the pixel structure layer, the bonding layer and the carrier plate;

removing the carrier plate and the junction layer to expose the surface of the pixel structure layer, wherein the support structure protrudes out of the surface of the pixel structure layer away from the circuit substrate and forms an accommodating space with the surface of the pixel structure layer;

forming a connecting layer in the accommodating space; and

and arranging a protective layer on the connecting layer to connect the protective layer with the pixel structure layer through the connecting layer.

13. The method of claim 12, wherein the step of forming the supporting structure on the surface of the circuit substrate further comprises:

the supporting structure is filled with a material between the pixel structure layer and the circuit substrate.

14. The method of claim 12, wherein before forming the connecting layer in the accommodating space, further comprising:

the thickness of the pixel structure layer is reduced through an etching process, and the height of the retaining wall of the supporting structure protruding out of the surface of the pixel structure layer is reduced.

15. The method of claim 14, wherein the support structure has a different etch rate than the pixel structure layer.

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