Patent ID: 12211815

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, or examples, for implementing different features of the subject matter provided. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, a first feature is formed on a second feature in the description that follows may include embodiments in which the first feature and second feature are formed in direct contact, and may also include embodiments in which additional features may be formed between the first feature and second feature, so that the first feature and second feature may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

It should be understood that additional steps may be implemented before, during, or after the illustrated methods, and some steps might be replaced or omitted in other embodiments of the illustrated methods.

Furthermore, spatially relative terms, such as “beneath,” “below,” “lower,” “on,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to other elements or features as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.

In the present disclosure, the terms “about,” “approximately” and “substantially” typically mean ±20% of the stated value, more typically ±10% of the stated value, more typically ±5% of the stated value, more typically ±3% of the stated value, more typically ±2% of the stated value, more typically ±1% of the stated value and even more typically ±0.5% of the stated value. The stated value of the present disclosure is an approximate value. That is, when there is no specific description of the terms “about,”; “approximately” and “substantially”, the stated value includes the meaning of “about,” “approximately” or “substantially”.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It should be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined in the embodiments of the present disclosure.

The present disclosure may repeat reference numerals and/or letters in following embodiments. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

FIG.1AtoFIG.1Bare partial cross-sectional views illustrating various stages of transferring the micro LED structure20onto the driving substrate10to form the micro LED display panel100according to an embodiment of the present disclosure. It should be noted that some components of the micro LED display panel100have been omitted inFIG.1AandFIG.1Bin order to show the technical features of the embodiments of the present disclosure more clearly.

Referring toFIG.1A, in some embodiments, a driving substrate10is provided. The driving substrate10may be for example, a display substrate, a light-emitting substrate, a substrate with functional elements such as thin-film transistors (TFT) or integrated circuits (IC), or other types of circuit substrates, but the present disclosure is not limited thereto. For example, the driving substrate10may be a bulk semiconductor substrate or include a composite substrate formed of different materials, and the driving substrate10may be doped (e.g., using p-type or n-type dopants) or undoped. In addition, the driving substrate10may include a semiconductor substrate, a glass substrate, or a ceramic substrate, such as a silicon substrate, a silicon germanium substrate, a silicon carbide substrate, an aluminum nitride substrate, a sapphire substrate, the like, or a combination thereof, but the present disclosure is not limited thereto.

Referring toFIG.1A, in some embodiments, multiple bonding pads12are formed on the driving substrate12. As shown inFIG.1A, in some embodiments, the bonding pads12are spaced apart from each other and disposed on the driving substrate12. The bonding pad12includes a conductive material, such as metal, metal silicide, the like, or a combination thereof, but the present disclosure is not limited thereto. For example, the metal may include gold (Au), nickel (Ni), platinum (Pt), palladium (Pd), iridium (Ir), titanium (Ti), chromium (Cr), tungsten (W), aluminum (Al), copper (Cu), the like, an alloy thereof, or a combination thereof, but the present disclosure is not limited thereto.

Moreover, the bonding pads12may be spaced apart from each other and disposed on the driving substrate12by a deposition process and a patterning process. The deposition process may, for example, include chemical vapor deposition (CVD), atomic layer deposition (ALD), spin-on coating, the like, or a combination thereof, but the present disclosure is not limited thereto. The patterning process may include forming a mask layer (not shown) on the aforementioned material, and then etching the portion of the aforementioned material that is not covered by the mask layer to form the bonding pads12that are spaced apart from each other, but the present disclosure is not limited thereto.

As shows inFIG.1A, in some embodiments, multiple distribution layers14are formed on the driving substrate10, and the distribution layers14are electrically connected to the bonding pads12. In particular, the distribution layers14may be in direct contact with the corresponding bonding pads12. The distribution layer14includes a conductive material, such as metal, metal silicide, the like, or a combination thereof, but the present disclosure is not limited thereto. Examples of the metal are described above, which will not be repeated herein. The material of the distribution layers14may be the same as or different from the material of the bonding pad12. For example, the distribution layers14may include copper (Cu), and the bonding pad12may include gold (Ag), but the present disclosure is not limited thereto. Moreover, the distribution layers14may be spaced apart from each other and disposed on the driving substrate12by a deposition process and a patterning process. Examples of the deposition process and the patterning process are described above, which will not be repeated herein.

As shown inFIG.1A, in some embodiments, multiple passivation layers16are formed on the distribution layers14. For example, the passivation layer16may include, for example, an oxide such as silicon oxide, a nitride such as silicon nitride, the like, or a combination thereof, but the present disclosure is not limited thereto. The passivation layers16may be formed on the distribution layers14by a deposition process. For example, the passivation layers16may be formed on the top surface14T of the distribution layers14as shown inFIG.1A, but the present disclosure is not limited thereto.

As shown inFIG.1A, in some embodiments, multiple isolation structures18are formed on the driving substrate10, and the isolation structures18are disposed on the side of the driving substrate10facing the micro LED structures20. In particular, as shown inFIG.1A, the isolation structure18may be disposed between a pair of bonding pads12(e.g., the bonding pad12-1and the bonding pad12-2shown inFIG.1A), but the present disclosure is not limited thereto. The isolation structure18may include an inorganic compound (e.g., silicon oxide, silicon nitride) or an organic compound with electrical insulation. Moreover, the isolation structures18may be formed on the driving substrate10by a deposition process and a patterning process. Examples of the deposition process and the patterning process are described above, which will not be repeated herein.

Referring toFIG.1A, in some embodiments, multiple micro LED structures20are provided. The micro LED structure20includes an epitaxial layer22, and the epitaxial layer22includes a first-type semiconductor layer, a light-emitting layer disposed on the first-type semiconductor layer, and a second-type semiconductor layer disposed on the light-emitting layer. In other words, the light-emitting layer is disposed between the first-type semiconductor layer and the second-type semiconductor layer, but the present disclosure is not limited thereto.

The first-type semiconductor layer includes N-type semiconductor material. For example, the first-type semiconductor layer may include a group II-VI material (e.g. zinc selenide (ZnSe)) or a group III-V material (e.g., gallium nitride (GaN), aluminum nitride (AlN), indium nitride (InN), indium gallium nitride (InGaN), aluminum gallium nitride (AlGaN) or aluminum indium gallium nitride (AlInGaN)), and the first-type semiconductor layer may include dopants such as silicon (Si) or germanium (Ge), but the present disclosure is not limited thereto. Moreover, the first-type semiconductor layer may be a single-layer or multi-layer structure.

The light-emitting layer includes at least one undoped semiconductor layer or at least one low-doped semiconductor layer. For example, the light-emitting layer may be a quantum well (QW) layer, which may include indium gallium nitride (InxGa1−xN) or gallium nitride (GaN), but the present disclosure is not limited thereto. Alternately, the light-emitting layer may be a multiple quantum well (MQW) layer, but the present disclosure is not limited thereto.

Moreover, the light-emitting layer may emit red light, green light, or blue light, but the present disclosure is not limited thereto. For example, the light-emitting layer may also emit white light, cyan light, magenta light, yellow light, any other color light, or a combination thereof.

The second-type semiconductor layer includes P-type semiconductor material. For example, the second-type semiconductor layer may include a group II-VI material (e.g., zinc selenide (ZnSe)) or a group III-V material (e.g., gallium nitride (GaN), aluminum nitride (AlN), indium nitride (InN), indium gallium nitride (InGaN), aluminum gallium nitride (AlGaN) or aluminum indium gallium nitride (AlInGaN)), and the second-type semiconductor layer may include dopants such as magnesium (Mg) or carbon (C), but the present disclosure is not limited thereto. Moreover, the second-type semiconductor layer may be a single-layer or multi-layer structure.

Referring toFIG.1A, in some embodiments, the micro LED structure20also includes an electrode26and an electrode28, the electrode26and the electrode28are disposed on the side of the micro LED structure20facing the driving substrate10and electrically connected to the epitaxial layer22. For example, the electrode26and the electrode28may be electrically connected to the first-type semiconductor layer and the second-type semiconductor layer (not shown in detail inFIG.1AandFIG.1B) respectively, but the present disclosure is not limited thereto.

The electrode26and the electrode28include a conductive material, such as metal, metal silicide, the like, or a combination thereof, but the present disclosure is not limited thereto. For example, the metal may include gold (Au), nickel (Ni), platinum (Pt), palladium (Pd), iridium (Ir), titanium (Ti), chromium (Cr), tungsten (W), aluminum (Al), copper (Cu), the like, an alloy thereof, or a combination thereof, but the present disclosure is not limited thereto. The electrode26and the electrode28may be formed by physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), evaporation, sputtering, the like, or a combination thereof, but the present disclosure is not limited thereto.

Referring toFIG.1A, in some embodiments, the micro LED structure20further includes an insulating layer24disposed on the epitaxial layer22. The insulating layer24may include, for example, an oxide such as silicon oxide, a nitride such as silicon nitride, the like, or a combination thereof, but the present disclosure is not limited thereto. The insulating layer24may be formed on the surface of the epitaxial layer22facing the driving substrate10and the side surface of the epitaxial layer22, but the present disclosure is not limited thereto. Moreover, a patterning process may be performed to remove a portion of the insulating layer24, so that the electrode26and the electrode28are electrically connected to the epitaxial layer22, but the present disclosure is not limited thereto. Examples of the deposition process and the patterning process are described above, which will not be repeated herein.

Referring toFIG.1B, the micro LED structures20and the driving substrate10are bonded to form the micro LED display panel100. For example, multiple micro LED structures20(only one micro LED structure20is shown inFIG.1B) may be transferred onto the driving substrate10by a (thermo-)compression bonding process, but the present disclosure is not limited thereto. As shown inFIGS.1A and1B, in some embodiments, the electrode26has a normal contact surface26N and a side contact surface26S, the normal contact surface26N faces the driving substrate10, and the side contact surface26S is laterally connected to the corresponding bonding pad12(i.e.,12-1). Similarly, as shown inFIGS.1A and1B, in some embodiments, the electrode28has a normal contact surface28N and a side contact surface28S, the normal contact surface28N faces the driving substrate10, and the side contact surface28S is laterally connected to the corresponding bonding pad12(i.e.,12-2).

As shown inFIG.1B, in the embodiment of the present disclosure, the micro LED display panel100includes a driving substrate10and a plurality of bonding pads12disposed on the driving substrate10and spaced apart from each other. The micro LED display panel100also includes a plurality of micro LED structures20electrically connected to the bonding pads12. Each micro LED structure20includes at least one electrode (26or28) disposed on the side of the micro LED structure20facing the driving substrate10. The electrode (26or28) has a normal contact surface (26N or28N) and a side contact surface (26S or28S), the normal contact surface (26N or28N) faces the driving substrate10, and the side contact surface (26S or28S) is laterally connected to the corresponding bonding pad12.

As shown inFIG.1B, in some embodiments, the normal contact surface26N of the electrode26and the normal contact surface28N of the electrode28are both in direct contact with the driving substrate10. In some other embodiments, the driving substrate10may additionally include other film layers (such as but not limited to a dielectric material layer) on its surface, and in the cases where the normal contact surface26N of electrode26and the normal contact surface28N of electrode28are in contact with the driving substrate10through these layers, these cases still belong to the above-mentioned in-direct-contact mode. Moreover, in some embodiments, the electrode26and the electrode28are between the bonding pad12-1and the bonding pad12-2, Moreover, in some embodiments, the isolation structure18is between the electrode26and the electrode28. The isolation structure18may be used to prevent the electrode26and the electrode28from being in contact with each other and causing a short circuit during the (thermo-)compression bonding process.

As shown inFIG.1B, the micro LED structure20is laterally connected to the bonding pad12-1and the bonding pad12-2on the driving substrate10by the side contact surface26S of the electrode26and the side contact surface28S of the electrode28respectively. Therefore, when the micro LED structure20is failed, the contact surface (i.e., the side contact surface26S of the electrode26) between the electrode26and the bonding pad12-1and the contact surface (i.e., the side contact surface28S of the electrode28) between the electrode28and the bonding pad12-2may be irradiated from the back surface10B of the driving substrate10by the laser LS to debond the faulty micro LED structure20. However, in other embodiments not shown in the figures, the laser LS may also irradiate the aforementioned contact surface from the front surface of the driving substrate10.

Since the bonding pad12-1and the bonding pad12-2are only partially melted at the contact surface between the electrode26and the bonding pad12-1and the contact surface between the electrode28and the bonding pad12-2, after the micro LED structure20is removed, the bonding pad12-1and the bonding pad12-2may be reused. That is, there is no need to reserve other spaces for additional bonding pads or to re-make bonding pads on the driving substrate10. In addition, the space of the removed micro LED structure20may directly accommodate (bond) a new micro LED structure.

FIG.2is a partial cross-sectional view illustrating the micro LED display panel102according to an embodiment of the present disclosure. Similarly, some components of the micro LED display panel102have been omitted inFIG.2in order to show the technical features of the embodiments of the present disclosure more clearly.

Referring toFIG.2, the micro LED display panel102has a structure similar to that of the micro LED display panel100shown inFIG.1B. The main difference is that the micro LED structure20′ of the micro LED display panel102shown inFIG.2further includes a molding layer29disposed on the side of the micro LED structure20′ facing the driving substrate10. As shown inFIG.2, the molding layer29has holes29O, and a portion of the electrode26and a portion of the electrode28are disposed in the holes29O.

The electrode26has a body portion26-1and an extension portion26-2, and the extension portion26-2is connected to the body portion26-1and extends to the surface29S of the molding layer29facing the driving substrate10through the hole29O. Similarly, the electrode28has a body portion28-1and an extension portion28-2, and the extension portion28-2is connected to the body portion28-1and extends to the surface29S of the molding layer29facing the driving substrate10through the hole29O.

In other words, inFIG.2, two electrodes (26and28) are laterally connected to the corresponding bonding pads (12-1and12-2) by, the side contact surfaces (26S and28S) of their extension portions (26-2and28-2) respectively. In this embodiment, the bonding pads12(e.g.,12-1and12-2) are in direct contact with the extension portions (26-2and28-2) of two electrode (26and28) of the micro LED structure20′.

Since the height of the body portions (26-1and28-1) of the electrodes (26and28) (i.e., the ohmic contact area on the side surface) will be limited as the size of the micro LED structure20′ shrinks, in the embodiment shown inFIG.2, the extension portions (26-2and28-2) help to enlarge the contact area between the electrodes (26and28) and the two bonding pads (12-1and12-2), thereby ensuring the bonding yield while optimizing the electroluminescence efficiency.

In some embodiments, the orthogonal projection of the extension portion26-2of the electrode26on the driving substrate10completely covers the orthogonal projection of the body portion26-1of the electrode26on the driving substrate10. Similarly, in some embodiments, the orthogonal projection of the extension portion28-2of the electrode28on the driving substrate10completely covers the orthogonal projection of the body portion28-1of the electrode28on the driving substrate10.

FIG.3is a partial cross-sectional view illustrating the micro LED display panel104according to another embodiment of the present disclosure.FIG.4is a partial cross-sectional view illustrating the micro LED display panel106according to another embodiment of the present disclosure.FIG.5is a partial cross-sectional view illustrating the micro LED display panel108according to another embodiment of the present disclosure.FIG.6is a partial cross-sectional view illustrating the micro LED display panel110according to another embodiment of the present disclosure. Similarly, some components of the micro LED display panel104, the micro LED display panel106, the micro LED display panel108, and the micro LED display panel110have been omitted inFIG.3toFIG.6in order to show the technical features of the embodiments of the present disclosure more clearly.

Referring toFIG.3, the micro LED display panel104has a structure similar to that of the micro LED display panel102shown inFIG.2. The main difference is that the bonding pad12(e.g., the bonding pad12-1or the bonding pad12-2) of the micro LED display panel104shown inFIG.3is disposed on the passivation layer16. In particular, the bonding pad12(e.g., the bonding pad12-1or the bonding pad12-2) is disposed on the top surface16T of the passivation layer16and in direct contact with the passivation layer16.

Referring toFIG.4, the micro LED display panel106has a structure similar to that of the micro LED display panel104shown inFIG.3. The main difference is that the bonding pad12(e.g., the bonding pad12-1or the bonding pad12-2) of the micro LED display panel106shown inFIG.4has a protruding part12P, and the protruding part12P may further increase the contact area between the bonding pad12(e.g., the bonding pad12-1or the bonding pad12-2) and (the extension portion26-2of) the electrode26or the (the extension portion28-2of) the electrode28.

Referring toFIG.5, the micro LED display panel108has a structure similar to that of the micro LED display panel102shown inFIG.2. The main difference is that the bonding pad12(e.g., the bonding pad12-1or the bonding pad12-2) of the micro LED display panel108shown inFIG.5is disposed between the driving substrate10and the passivation layer16. In particular, the bonding pad12(e.g., the bonding pad12-1or the bonding pad12-2) is disposed on the bottom surface16B of the passivation layer16and in direct contact with the driving substrate10and the passivation layer16.

Referring toFIG.6, the micro LED display panel110has a structure similar to that of the micro LED display panel102shown inFIG.2. The main difference is that one bonding pad12(e.g., the bonding pad12-1) of the micro LED display panel110shown inFIG.6is disposed on the passivation layer16, and another bonding pad12(e.g., the bonding pad12-2) of the micro LED display panel110shown inFIG.6is disposed between the driving substrate10and the passivation layer16. In particular, the bonding pad12-1is disposed on the top surface16T of the passivation layer16and in direct contact with the passivation layer16, and the bonding pad12-2is disposed on the bottom surface16B of the passivation layer16and in direct contact with the driving substrate10and the passivation layer16.

In summary, in the micro LED display panels (104,106,108, and110) shown inFIG.3toFIG.6, the bonding pads12may be arranged at positions corresponding to the distribution layers14inFIG.2. In other words, since the present disclosure adopts a laterally connected structure and the micro LED structure20(or20′) may still be reused after the laser trimming process, in the embodiments shown in the foregoing drawings, the bonding pads12may also refer to a part of the circuit layout of the distribution layers14and is not limited to the independent element illustrated inFIG.2.

FIG.7is a partial cross-sectional view illustrating the micro LED display panel112according to an embodiment of the present disclosure.FIG.8is a partial cross-sectional view illustrating the micro LED display panel114according to another embodiment of the present disclosure. Similarly, some components of the micro LED display panel112and the micro LED display panel114have been omitted inFIG.7andFIG.8in order to show the technical features of the embodiments of the present disclosure more clearly.

Referring toFIG.7, the micro LED display panel112has a structure similar to that of the micro LED display panel100shown inFIG.1B. The main difference is that the electrode26′ and the electrode28′ of the micro LED display panel112shown inFIG.7respectively have overlapping areas (i.e., the rounded corners enclosed by the dotted circle inFIG.7), so that the orthogonal projections of the electrode26′ and the electrode28′ on the driving substrate10partially overlap the orthogonal projection of the corresponding bonding pads12(i.e., the bonding pads12-1and12-2) on the driving substrate10.

In some embodiments, the orthogonal projection of the electrode26′ on the driving substrate10and the orthogonal projection of the corresponding bonding pad12(i.e., the bonding pad12-1) on the driving substrate10have an overlapping area, and the overlapping area takes up less than 30% of the area of the orthogonal projection of the electrode26′ on the driving substrate10. Similarly, in some embodiments, the overlapping area of the orthogonal projection of the electrode28′ on the driving substrate10and the orthogonal projection of the corresponding bonding pad12(i.e., the bonding pad12-2) on the driving substrate10takes up less than 30% of the area of the orthogonal projection of the electrode28′ on the driving substrate10.

In general, when the electrodes of the micro LED are bonded to the bumps (e.g., the bonding pads) on the substrate, a horizontal shift may likely occur. In the embodiment shown inFIG.7, since each micro LED structure20is laterally (or substantially vertically) connected to the corresponding bonding pad12-1and bonding pad12-2on the driving substrate10by the side contact surface26S of the electrode26′ and the side contact surface28S of the electrode28′, respectively, the bonding pad12-1and the bonding pad12-2will automatically adapt to the shape of the electrode26′ and the electrode28′ to fill the gap there, so that the electrical conductivity of the micro LED structure20and the driving substrate10will not be affected by the horizontal shift.

The shape of the overlapping areas of the electrode26′ and of the electrode28′ (i.e., the rounded corners enclosed by the dotted circle inFIG.7) is formed, for example, because the patterned distance between the bonding pad12-1and the bonding pad12-2(i.e., the shortest distance between the bonding pad12-1and the bonding pad12-2in the horizontal direction) is slightly smaller than the boundary width of the electrode26′ and the electrode28′ (i.e., the longest distance between the electrode26′ and the electrode28′ in the horizontal direction), so that the micro LED structure20will naturally press the bonding pad12-1and the bonding pad12-2during the compression process to form an overlapping area. In other words, it means that the two electrodes (i.e., the electrode26′ and the electrode28′) and the bonding pads12(i.e., the bonding pad12-1and the bonding pad12-2) are in close contact.

Therefore, in the embodiments of the present disclosure, it does not increase the risk of short circuit to shorten the distance between the bonding pads12e.g., the bonding pad12-1and the bonding pad12-2) because the bonding pads may be separated by the micro LED structure20. In contrast, in a general micro LED display panel, since the electrodes of the micro LED are frontally bonded (i.e., normally bonded) to bumps (e.g., bonding pads) on the substrate, the aforementioned effect cannot be achieved, and it may increase the risk of short circuit to shorten the distance (pitch) between the bumps.

Referring toFIG.8, the micro LED display panel114has a structure similar to that of the micro LED display panel100shown inFIG.1B. The main difference is that in the micro LED display panel114shown inFIG.8, the side contact surface26S where the electrode26″ is laterally connected to the corresponding bonding pad12(i.e., the bonding pad12-1) is an inclined surface. Similarly, the side contact surface28S where the electrode28″ is laterally connected to the corresponding bonding pad12(i.e., the bonding pad12-2) is also an inclined surface.

As shown inFIG.8, in some embodiments, the included angle θ1between the side contact surface26S of the electrode26″ and the driving substrate10is greater than about 45 degrees and less than about 90 degrees. Similarly, in some embodiments, the included angle θ2between the side contact surface28S of the electrode28″ and the driving substrate10is greater than about 45 degrees and less than about 90 degrees. In the embodiment shown inFIG.8, the included angle θ1is the same as the included angle θ2, but the present disclosure is not limited thereto. In some other embodiments, the included angle θ1is different from the included angle θ2.

FIG.9toFIG.13are different examples of the bonding pads12(that include the bonding pad12-1and the bonding pad12-2). In addition,FIG.9toFIG.13also illustrate the passivation layer16in order to more clearly show the corresponding relationship between the bonding pad12-1and the bonding pad12-2. However, it should be noted that not all micro LED display panels need to include the passivation layer16.

Referring toFIG.9, the shape of the bonding pad12-1and the shape of the bonding pad12-2are straight-line shapes, and the bonding pad12-1and the bonding pad12-2are arranged as a pair. In the top view shown inFIG.9, the bonding pad12-1and the bonding pad12-2are centrosymmetric. When the micro LED structure20and the driving substrate10are bonded, even if there is an alignment error between the micro LED structure20and the driving substrate10(e.g., the case shown inFIG.9), the bonding pad12-1and the bonding pad12-2may still be laterally connected to the electrode26and the electrode28. That is, the lateral connection provides a function that the bonding pad12-1and the bonding pad12-2to be stopped by abutting against the electrode26and the electrode28, which may be used to correct the alignment error caused by the horizontal shift or rotation during the alignment.

Referring toFIG.10, the shape of the bonding pad12-1and the shape of the bonding pad12-2are L shapes, and the bonding pad12-1and the bonding pad12-2are arranged as a pair. In the top view shown inFIG.10, the bonding pad12-1and the bonding pad12-2are centrosymmetric. When the micro LED structure20and the driving substrate10are bonded, even if there is an alignment error between the micro LED structure20and the driving substrate10(e.g., the case shown inFIG.10), the bonding pad12-1and the bonding pad12-2may still be laterally connected to the electrode26and the electrode28. That is, the bonding pad12-1and the bonding pad12-2are provided with the stopping effect, which may be used to correct the alignment error caused by the horizontal shift or rotation during the alignment.

In addition, inFIG.9andFIG.10, the configurations of the bonding pad12-1and the bonding pad12-2are also anti-symmetric. That is, in the arrangement area of the drive substrate10, the orthogonal projection patterns of the bonding pad12-1and the bonding pad12-2are upside-down and left-right opposite to each other based on their center lines.

The electrode26and the electrode28(and the micro LED structure20) will be omitted inFIG.11toFIG.13, and the stopping effect produced by the bonding pad12-1and the bonding pad12-2inFIG.11toFIG.13will not be repeated.

Referring toFIG.11, the shape of the bonding pad12-1and the shape of the bonding pad12-2are hollow squares, and the bonding pad12-1and the bonding pad12-2are arranged as a pair. In the top view shown inFIG.11, the bonding pad12-1and the bonding pad12-2are axial symmetric and centrosymmetric.

Referring toFIG.12, the shape of the bonding pad12-1and the shape of the bonding pad12-2are U shapes, the openings of the U shapes face each other, and the bonding pad12-1and the bonding pad12-2are arranged as a pair. In the top view shown inFIG.12, the bonding pad12-1and the bonding pad12-2are axial symmetric and centrosymmetric.

Referring toFIG.12, the shape of the bonding pad12-1and the shape of the bonding pad12-2are straight-line shapes, and the bonding pad12-1and the bonding pad12-2are arranged as a pair. In the top view shown inFIG.13, the bonding pad12-1and the bonding pad12-2are axial symmetric and centrosymmetric.

Concluding the foregoing paragraphs and the descriptions inFIG.9toFIG.13, it can be seen that since the micro LED structure and the drive substrate are bonded by the pressure from front side, when the position is aligned, various factors may cause alignment errors from the horizontal shift. In the present disclosure, since the bonding pad12-1and the bonding pad12-2are arranged on the sides of the electrode26and the electrode28(both in the horizontal direction), even if the aforementioned error situation exists, the bonding yield of the micro LED structure will not be affected. Furthermore, for example, inFIG.9andFIG.10, the horizontal shift or rotation of the electrode26and the electrode28may increase the contact area with the bonding pad12-1and the bonding pad12-2.

As noted above, in the embodiments of the present disclosure, since each micro LED structure is laterally connected to the bonding pad on the driving substrate by the side contact surface of the electrode, when the contact surface between the electrode and the bonding pad is irradiated (for example from the back of the driving substrate) by the laser to debond the faulty micro LED structure, the bonding pad is only partially melted at the contact surface. Therefore, the bonding pad may be reused, and there is no need to reserve other spaces for additional bonding pads or to re-make bonding pad. In addition, the space of the removed micro LED structure may directly accommodate (bond) a new micro LED structure.

The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection should be determined through the claims. In addition, although some embodiments of the present disclosure are disclosed above, they are not intended to limit the scope of the present disclosure.

Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present disclosure should be or are in any single embodiment of the disclosure. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Thus, discussions of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.

Furthermore, the described features, advantages, and characteristics of the disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description provided herein, that the disclosure can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the disclosure.