Light-emitting module manufacturing method, light-emitting module and light-emitting device

Abstract

The invention relates to a light-emitting module manufacturing method, a light-emitting module and a light-emitting device. The manufacturing method of the light-emitting module comprises the following steps: providing a chip fixing film on which a plurality of mini light-emitting chips are laid; obtaining a test classification result of the mini light-emitting chips; the mini light-emitting chips are transferred to a temporary substrate according to a test classification result, the mini light-emitting chips on the temporary substrate all belong to preset classifications, and electrodes of the mini light-emitting chips face the side away from the temporary substrate; enabling the temporary substrate to be opposite to the packaging substrate, transferring the mini light-emitting chips from the temporary substrate to the packaging substrate in batches, bonding the transferred mini light-emitting chips with the packaging substrate, and separating the mini light-emitting chips from the temporary substrate. In some implementation processes, the efficiency of transferring the mini light-emitting chips to the packaging substrate is improved.

Description

Technical Field

[0001] The present application relates to the field of mini light-emitting chips, and in particular to a light-emitting module manufacturing method, a light-emitting module and a light-emitting device. Background Art

[0002] Mini LED (Mini Light Emitting Diode) chip (referred to as: mini light-emitting chip in this application) refers to an LED (Light Emitting Diode) chip with a chip long side size between 100 and 300um. Mini light-emitting chips are the result of the continued reduction in the size of small-pitch LED chips. Mini light-emitting chip technology is mature and mass production is feasible. It is expected to be widely used in mid-to-high-end LCD backlights and LED displays, especially in the fields of televisions, notebooks, and monitors. Due to the reduction in the size of mini light-emitting chips, the number of mini light-emitting chips on a chip is relatively large, and with the improvement of display technology, the number of mini light-emitting chips required in display products is also relatively large. For example, the Mini LED0406 chip, the number of mini light-emitting chips in a single chip can reach 648K. How to quickly transfer so many mini light-emitting chips to the packaging substrate has become a problem that needs to be urgently solved for the development of the Mini LED industry.

[0003] Therefore, how to improve the efficiency of transferring mini light-emitting chips to the packaging substrate is an urgent problem to be solved. Summary of the invention

[0004] In view of the deficiencies of the above-mentioned related technologies, the purpose of the present application is to provide a light-emitting module manufacturing method, a light-emitting module and a light-emitting device, aiming to solve the problem of insufficient efficiency in transferring mini light-emitting chips to a packaging substrate.

[0005] A method for manufacturing a light-emitting module, comprising:

[0006] Providing a chip fixing film on which a plurality of mini light-emitting chips are laid;

[0007] Obtaining a test classification result of the mini light-emitting chip;

[0008] Transferring the mini light-emitting chips to a temporary substrate according to the test classification result, wherein the mini light-emitting chips on the temporary substrate all belong to a predetermined classification, and the electrodes of the mini light-emitting chips face a side away from the temporary substrate;

[0009] The temporary substrate is positioned opposite to the packaging substrate.

[0010] The mini light-emitting chips are transferred in batches from the temporary substrate to the packaging substrate, and the transferred mini light-emitting chips are bonded to the packaging substrate and separated from the temporary substrate.

[0011] In the above-mentioned light-emitting module manufacturing method, the mini light-emitting chips are first transferred to a temporary substrate, and then transferred to a packaging substrate in batches through the temporary substrate. In some implementation processes, the efficiency of the packaging substrate when the mini light-emitting chips are transferred can be doubled.

[0012] Optionally, the step of transferring the mini light-emitting chip on the chip fixing film to a temporary substrate according to the test classification result includes:

[0013] The transfer device simultaneously picks up a plurality of the mini light-emitting chips and transfers the picked-up mini light-emitting chips to the temporary substrate;

[0014] The transfer device is separated from the mini light-emitting chip, and the mini light-emitting chip remains on the temporary substrate.

[0015] Using a transfer device that can pick up multiple mini light-emitting chips at the same time can increase the transfer efficiency exponentially.

[0016] Optionally, the step of providing a chip fixing film on which a plurality of mini light-emitting chips are laid includes:

[0017] Providing a chip fixing film on which the unsorted mini light-emitting chip is laid, wherein the electrode of the mini light-emitting chip faces a side close to the chip fixing film;

[0018] placing the chip fixing film and the temporary substrate opposite to each other;

[0019] The mini light emitting chips of predetermined categories on the chip fixing film are transferred to the temporary substrate, and the mini light emitting chips are bonded to the temporary substrate and separated from the chip fixing film.

[0020] The sorted mini light-emitting chips are no longer carried by the chip fixing film, which saves the use of the chip fixing film. The sorting step is combined with the step of transferring the mini light-emitting chips to the temporary substrate, and there is no need to move the mini light-emitting chips from the chip fixing film to the temporary substrate after sorting, which simplifies the process.

[0021] Optionally, the step of transferring the mini light-emitting chips of a predetermined category on the chip fixing film to the temporary substrate includes:

[0022] The mini light-emitting chip is transferred to the temporary substrate by means of thorn crystal transfer.

[0023] The speed of crystal transfer is faster than the traditional crystal bonding method, which improves the overall production efficiency of the light-emitting module.

[0024] Based on the same inventive concept, the present application also provides a light-emitting module, including:

[0025] A packaging substrate and a mini light-emitting chip, wherein the mini light-emitting chip is bonded to the packaging substrate through the steps of the above-mentioned light-emitting module manufacturing method.

[0026] When the light-emitting module of this embodiment is manufactured, the transfer efficiency of the mini light-emitting chip to the packaging substrate is higher, and it can also be manufactured more efficiently in some implementation processes.

[0027] Based on the same inventive concept, the present application also provides a light-emitting device, comprising the above-mentioned light-emitting module and a frame, wherein the light-emitting module is arranged on the frame.

[0028] The light-emitting module in the above-mentioned light-emitting device can be efficiently manufactured, thereby ensuring the production efficiency of the light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of a process for manufacturing a light-emitting module provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of a mini light-emitting chip provided in an embodiment of the present application on a temporary substrate;

[0031] Figure 3 A schematic diagram showing a temporary substrate and a packaging substrate provided in an embodiment of the present application relative to each other;

[0032] Figure 4 A schematic diagram of a mini light-emitting chip provided in an embodiment of the present application on a packaging substrate;

[0033] Figure 5 A schematic diagram of the manufacturing process of a mini light-emitting chip provided in an embodiment of the present application;

[0034] Figure 6 A schematic diagram of a manufacturing process of a mini light-emitting chip provided in an embodiment of the present application;

[0035] Figure 7 A schematic diagram of the process of making a light-emitting module in the related technology;

[0036] Figure 8 A schematic diagram of setting a chip fixing film according to an embodiment of the present application;

[0037] Fig. 9 A schematic diagram of testing and sorting mini light-emitting chips provided in an embodiment of the present application;

[0038] Fig.10 A schematic diagram of a mini light-emitting chip after film inversion provided in an embodiment of the present application;

[0039] Fig.11A schematic diagram of transferring a mini light-emitting chip provided in an embodiment of the present application;

[0040] Fig.12 A detailed process diagram of the light-emitting module manufacturing method provided in the embodiment of the present application Figure 1 ;

[0041] Fig.13 A detailed process diagram of the light-emitting module manufacturing method provided in the embodiment of the present application Figure 2 ;

[0042] Fig.14 A detailed process diagram of the light-emitting module manufacturing method provided in the embodiment of the present application Figure 3 ;

[0043] Fig.15 A schematic diagram of a process for manufacturing a light-emitting module according to Example 1 of an embodiment of the present application;

[0044] Fig.16 A schematic diagram of the manufacturing process of the light-emitting module manufacturing method of Example 1 provided in an embodiment of the present application;

[0045] Fig.17 A schematic diagram of a process for manufacturing a light emitting module according to Example 2 of an embodiment of the present application;

[0046] Fig.18 A schematic diagram of the manufacturing process of the light emitting module manufacturing method of Example 2 provided in the embodiment of the present application;

[0047] Description of reference numerals:

[0048] 1-temporary substrate; 2-adhesion layer; 3-mini light-emitting chip; 31-electrode; 301-substrate; 302-N-type semiconductor layer; 303-active layer; 304-P-type semiconductor layer; 305-transparent conductive layer; 306-metal electrode; 307-passivation layer; 4-packaging substrate; 41-bonding layer; 5-first chip fixing film; 6-second chip fixing film; 7-pickup head; 8-third chip fixing film; 9-transfer stamp; 10-thrust pin; L-laser. DETAILED DESCRIPTION

[0049] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thoroughly and comprehensively understood.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0051] The efficiency of transferring mini light-emitting chips to the packaging substrate is not high. How to quickly transfer the mini light-emitting chips to the packaging substrate has become an urgent problem to be solved in the development of the Mini LED industry.

[0052] Based on this, the present application hopes to provide a solution that can solve the above-mentioned technical problems, the details of which will be described in the subsequent embodiments.

[0053] Example:

[0054] This embodiment provides a method for manufacturing a light emitting module. Figure 1 , the steps include but are not limited to:

[0055] S101, providing a chip fixing film on which a plurality of mini light-emitting chips are laid;

[0056] The chip fixing film is used to fix the mini light-emitting chip 3 for flipping and transportation, and can also provide protection for the mini light-emitting chip 3 to prevent it from falling off or breaking when the wafer is cut. The chip fixing film can be selected according to the actual processing technology of the mini light-emitting chip 3. In this embodiment, the chip fixing film can be a blue film or an ultraviolet irradiation tape, wherein the ultraviolet irradiation tape is also called UV (ultraviolet) film or UV viscosity-reducing film, which has high viscosity before ultraviolet irradiation and reduces viscosity after ultraviolet irradiation.

[0057] S102, obtaining the test classification result of the mini light-emitting chip;

[0058] The uniformity of the epitaxial layer on the wafer is not consistent everywhere, and the mini light-emitting chips 3 formed have differences in performance including but not limited to brightness, operating voltage, color, etc. The relevant performance of each mini light-emitting chip 3 is tested, and the mini light-emitting chips 3 with relatively similar performance are classified into the same category (usually expressed as Bin value, but not limited to this). In some production processes, mini light-emitting chips 3 of the same category are usually loaded into the same container, and this process is also called Bin (box). When making a light-emitting module, mini light-emitting chips 3 of the same or similar classification are selected, so that each mini light-emitting chip 3 has higher consistency and better electrical properties and visual effects.

[0059] In this embodiment, obtaining the test classification result of the mini light-emitting chip 3 means determining the classification of the mini light-emitting chip 3 for subsequent sorting operations. It should be noted that the sorting operation can be performed immediately after the test. For example, in some implementation processes, the test and sorting can be performed by the same device, and the tested mini light-emitting chip 3 is sorted after the test is completed or during the test. In some implementation processes, the test and sorting can also be divided into two stages, that is, first obtain the test classification result, record the position of each mini light-emitting chip 3 and its corresponding performance parameters (or Bin value), and then perform the sorting operation through other devices. In the light-emitting module manufacturing method of this embodiment, different sorting methods can be used corresponding to different manufacturing steps, and this embodiment will be described later.

[0060] S103, transferring the mini light-emitting chip to a temporary substrate according to the test classification results;

[0061] It should be noted that the mini light-emitting chips 3 on the temporary substrate 1 all belong to a predetermined category, that is, their Bin values ​​are one or at least two specified ones. In practical applications, for the same product, mini light-emitting chips 3 of the same color are usually selected to be of the same category, but this embodiment does not limit this. Mini light-emitting chips 3 that do not belong to the predetermined category will not be transferred to the temporary substrate 1. Of course, in practical applications, mini light-emitting chips 3 of other categories can be transferred to other carriers. Figure 2 As shown, a plurality of mini light-emitting chips 3 are transferred onto the temporary substrate 1 , and the electrodes 31 of the mini light-emitting chips 3 are all facing the side away from the temporary substrate 1 .

[0062] In this embodiment, the mini light-emitting chips 3 can be pre-sorted onto a chip fixing film, and the same type of mini light-emitting chips 3 are usually arranged on the same chip fixing film. When transferring the mini light-emitting chips 3 to the temporary substrate 1, the mini light-emitting chips 3 are obtained from the same chip fixing film, so that the mini light-emitting chips 3 on the temporary substrate 1 are all of the same type. Of course, the mini light-emitting chips 3 can also be directly transferred to the temporary substrate 1 when being sorted, so that the mini light-emitting chips 3 on the temporary substrate 1 are also of the same type. For the implementation method in which a plurality of different types of mini light-emitting chips 3 need to be arranged on the temporary substrate 1, the same is true, and the mini light-emitting chips 3 are obtained from the corresponding chip fixing films, or the corresponding mini light-emitting chips 3 are directly transferred to the temporary substrate 1 as needed during sorting.

[0063] The electrode 31 of the mini light-emitting chip 3 on the chip fixing film may face the chip fixing film, or may face the side away from the chip fixing film. Regardless of how the mini light-emitting chip 3 is oriented on the chip fixing film, during the transfer to the temporary substrate 1, it is adjusted to contact the temporary substrate 1 with the side without the electrode 31. Exemplarily, for a mini light-emitting chip 3 that does not need to adjust the orientation of the electrode 31 (that is, the position of the electrode 31 relative to the carrier before and after the transfer does not change), it can be transferred by methods including but not limited to picking up and placing; for a mini light-emitting chip 3 that needs to adjust the orientation of the electrode 31, it can be transferred by methods including but not limited to acupuncture, relative fitting of the temporary substrate 1 and the chip fixing film, etc.

[0064] In this embodiment, the temporary substrate 1 may be a hard substrate including but not limited to a glass substrate, a sapphire substrate, etc. The hard temporary substrate 1 is more stable, less likely to deform during the transfer process, and has a longer service life. Figure 2 As shown, in order to transfer the mini light-emitting chip 3 to the temporary substrate 1, an adhesive layer 2 is further provided on one side of the temporary substrate 1, and the mini light-emitting chip 3 is bonded to the adhesive layer 2 of the temporary substrate 1. The adhesive strength of the adhesive layer 2 is configured so that the mini light-emitting chip 3 can be stably fixed on the temporary substrate 1, and the transfer process can be ensured to proceed normally during the transfer process. As an example, if the mini light-emitting chip 3 is picked up and transferred by a transfer device with viscosity, the adhesive strength of the adhesive layer 2 can be configured to be greater than the viscosity of the transfer device, so as to ensure that the picked mini light-emitting chip 3 remains on the temporary substrate 1. On the other hand, the adhesive strength of the adhesive layer 2 can be less than the bonding strength between the mini light-emitting chip 3 and the packaging substrate 4, so that after the mini light-emitting chip 3 on the temporary substrate 1 is bonded to the packaging substrate 4, the mini light-emitting chip 3 remains on the packaging substrate 4.

[0065] In practical applications, for a higher transfer yield, the adhesive layer 2 may be made of a material that weakens or contacts the adhesiveness under predetermined conditions, such as photodissolved adhesive, thermal dissolved adhesive, etc. As an example, the adhesive layer 2 is made of photodissolved adhesive, and the temporary substrate 1 may be made of a transparent material. The adhesive layer 2 is irradiated with predetermined light to weaken or contact the adhesiveness of the adhesive layer 2, which makes the mini light-emitting chip 3 more successful when being transferred to the packaging substrate 4, and no residue will remain on the temporary substrate 1.

[0066] S104, making the temporary substrate face the packaging substrate, and transferring the mini light-emitting chips from the temporary substrate to the packaging substrate in batches;

[0067] like Figure 3As shown, the electrode 31 of the mini light-emitting chip 3 on the temporary substrate 1 is opposite to the bonding layer 41 on the packaging substrate 4, and the electrode 31 is aligned with the bonding layer 41 on the packaging substrate 4. It can be understood that in this embodiment, when the mini light-emitting chip 3 is transferred to the temporary substrate 1, the mini light-emitting chip 3 is arranged according to the arrangement of the bonding layer 41 on the packaging substrate 4, so that after the temporary substrate 1 and the packaging substrate 4 are aligned in a predetermined posture, the mini light-emitting chip 3 to be transferred is aligned with the bonding layer 41 on the packaging substrate 4.

[0068] The bonding layer 41 of the packaging substrate 4 includes but is not limited to conductive bonding materials such as solder, and the mini light-emitting chip 3 is bonded to the bonding layer 41 to achieve a fixed electrical connection.

[0069] like Figure 4 As shown, the transferred mini light-emitting chip 3 is bonded to the packaging substrate 4, and its electrode 31 is bonded to the bonding layer 41 of the packaging substrate 4, and the temporary substrate 1 is separated from the mini light-emitting chip 3. The transfer method of the mini light-emitting chip 3 may include relatively fitting the aligned temporary substrate 1 to the packaging substrate 4, so that the electrode 31 of the mini light-emitting chip 3 contacts the bonding layer 41 and completes the bonding, and then peeling off the temporary substrate 1. The transfer method of the mini light-emitting chip 3 may also include releasing the adhesion between the mini light-emitting chip 3 and the temporary substrate 1, so that the mini light-emitting chip 3 detaches from the temporary substrate 1 under the action of gravity and falls onto the packaging substrate 4, and then achieves bonding.

[0070] Since the temporary substrate 1 carries multiple mini light-emitting chips 3, and the electrodes 31 of the mini light-emitting chips 3 to be transferred have been aligned with the bonding layer 41, during the transfer process of step S104, batch transfer of the mini light-emitting chips 3 to the packaging substrate 4 can be achieved, which significantly improves the efficiency of transferring the mini light-emitting chips 3 to the packaging substrate 4.

[0071] In order to better understand the manufacturing process of the light emitting module of this embodiment, the manufacturing process of the light emitting module using the mini light emitting chip 3 in the related art is also described below. Before manufacturing the light emitting module, it is also necessary to provide a mini light emitting chip 3. For example, see Figure 5 as well as Figure 6 As shown, the manufacturing process of the mini light emitting chip 3 includes but is not limited to:

[0072] S201, providing a wafer;

[0073] like Figure 6As shown in (a), the wafer includes a substrate 301 and an epitaxial layer, wherein the substrate 301 includes but is not limited to a substrate 301 capable of growing semiconductor materials such as a sapphire substrate and a silicon substrate, and the epitaxial layer includes but is not limited to an N-type semiconductor layer 302, a P-type semiconductor layer 304, and an active layer 303 between the N-type semiconductor layer 302 and the P-type semiconductor layer 304. The material of the epitaxial layer mainly includes gallium nitride (GaN), but other semiconductor materials such as gallium arsenide may also be used in some implementation processes.

[0074] In this step, a mesa pattern is formed by photoetching on the epitaxial layer, so that the P-type semiconductor layer 304 and the active layer 303 in the epitaxial layer are partially removed, and the N-type semiconductor layer 302 is exposed. Taking gallium nitride as an example, the P-type semiconductor layer 304 and the active layer 303 can be etched by dry etching using BCl3Cl2 as an etching gas. The etching depth can be 1-2um. After the etching is completed, the residual photoresist is removed to obtain a mesa pattern.

[0075] S202, forming a transparent conductive layer;

[0076] like Figure 6 As shown in (b), a transparent conductive layer 305 is sputtered on the epitaxial layer, and the material of the transparent conductive layer 305 includes but is not limited to ITO (Indium Tin Oxide), and the thickness thereof can be 200-2000 Å. Exemplarily, a pattern is photoetched on the sputtered ITO material, and the ITO material is wet-etched and debonded to obtain the transparent conductive layer 305.

[0077] S203, forming a cutting path pattern;

[0078] like Figure 6 As shown in (c), after the transparent conductive layer 305 is manufactured, the epitaxial layer is etched to the substrate 301. The area etched to the substrate 301 is the cutting path, so that a plurality of independent epitaxial layer areas are divided on the epitaxial wafer, and each epitaxial layer area can be made into an independent mini light-emitting chip 3. After the mini light-emitting chip 3 is manufactured, the epitaxial wafer can be cut and split along the position of the cutting path, so that each mini light-emitting chip 3 is separated into an independent individual. Exemplarily, the photoresist can be first exposed and developed to form a corresponding pattern of the photoresist, and then the cutting path is manufactured by dry etching process using the photoresist as a mask. When the main component of the epitaxial layer includes gallium nitride, the etching gas can include but is not limited to BCl3Cl2, and the etching depth is 4-8um. The cutting path pattern is obtained after degumming.

[0079] S204, forming a metal electrode;

[0080] like Figure 6As shown in (d), a metal layer is provided by evaporation or the like, and a pattern of a metal electrode 306 is formed after photolithography and stripping. The thickness of the metal electrode 306 may be 1-3 um.

[0081] S205, forming a passivation layer;

[0082] like Figure 6 As shown in (e), a passivation material is deposited and a passivation layer 307 is formed by photolithography. The passivation material can be removed by dry etching. The etching gas can include but is not limited to CF4O2Ar. After etching, the photoresist can be removed. Exemplarily, the passivation layer 307 can also be a DBR (Distributed Bragg Reflection) layer.

[0083] S206, forming an electrode;

[0084] like Figure 6 As shown in (f), the material of the electrode 31 is disposed on the surface of the passivation layer 307 by evaporation or the like, and the pattern of the electrode 31 is obtained by photolithography. The thickness of the electrode 31 can be 1-3 um, and it is connected to the metal electrode 306 through the through hole on the passivation layer 307. The wafer formed at this time can be cut to obtain a single mini light-emitting chip 3.

[0085] It is understandable that the mini light emitting chip 3 in this embodiment can also be manufactured by steps including but not limited to the above-mentioned examples. This embodiment does not limit the manufacturing process and specific structure of the mini light emitting chip 3.

[0086] Following the previous example, see Figure 7 The manufacturing process of the light-emitting module using the mini light-emitting chip 3 in the related art also includes:

[0087] S301, cutting the wafer into individual mini light-emitting chips;

[0088] After the aforementioned wafer is obtained, the wafer is cut to separate the epitaxial layer into a plurality of mutually independent individuals, each of which is a mini light-emitting chip 3 .

[0089] Before cutting, the substrate 301 may be thinned to facilitate cutting and reduce the volume of the mini light-emitting chip 3 finally obtained. Figure 8As shown, in order to protect the mini light-emitting chip 3, prevent the cut mini light-emitting chip 3 from detaching or causing edge collapse during the cutting process, and facilitate subsequent transportation and processing, a chip fixing film, such as ultraviolet irradiation tape or blue film, is usually provided on the wafer. In this example, the chip fixing film is provided on the side of the substrate 301 away from the mini light-emitting chip 3. After the wafer is cut, a chip fixing film with a plurality of independent mini light-emitting chips 3 is obtained. For ease of explanation, the chip fixing film is hereinafter referred to as the first chip fixing film 5; in this application, the chip fixing film is distinguished in the order of "first" and "second" according to the order of use in a single production process, that is, the first chip fixing film used is called the first chip fixing film 5, the second chip fixing film used is called the second chip fixing film 6, and so on.

[0090] S302, testing and sorting the mini light-emitting chips;

[0091] like Fig. 9 As shown, the mini light-emitting chips 3 are tested and sorted by the testing and sorting equipment. During the sorting process, the mini light-emitting chips 3 of the same category are sorted onto the same second chip fixing film 6. The mini light-emitting chips 3 of the corresponding category on the first chip fixing film 5 are picked up one by one by the picking head 7 and placed on the second chip fixing film 6 of the corresponding category.

[0092] S303, performing film inversion on the mini light-emitting chip;

[0093] like Fig.10 As shown, the electrode 31 of the mini light-emitting chip 3 on the second chip fixing film 6 after sorting is oriented toward the side away from the second chip fixing film 6, a third chip fixing film 8 is arranged on the side of the electrode 31 of the mini light-emitting chip 3, and the second chip fixing film 6 is removed, so that the electrode 31 of the mini light-emitting chip 3 is in a state close to the third chip fixing film 8.

[0094] S304, placing the mini light-emitting chips one by one on the packaging substrate by using a pickup head;

[0095] like Fig.11 As shown, the pickup head 7 picks up the mini light emitting chip 3 and moves it to the packaging substrate 4, and the electrode 31 of the mini light emitting chip 3 is located on the side close to the packaging substrate 4. When the mini light emitting chip 3 is placed on the packaging substrate 4, its electrode 31 can contact the bonding layer 41 of the packaging substrate 4.

[0096] After the mini light emitting chip 3 is placed on the packaging substrate 4 , the mini light emitting chip 3 is bonded to the bonding layer 41 , and the packaging substrate 4 bonded with the mini light emitting chip 3 is obtained.

[0097] It can be seen that in the conventional light-emitting module using mini light-emitting chips 3, the packaging substrate 4 needs to be transferred with the mini light-emitting chips 3 one by one, which is inefficient. In contrast, the present application first transfers the mini light-emitting chips 3 to the temporary substrate 1, and then transfers them to the packaging substrate 4 in batches through the temporary substrate 1. In some implementation processes, the efficiency of the packaging substrate 4 when transferring the mini light-emitting chips 3 can be doubled.

[0098] In some embodiments, the step of providing a chip fixing film on which a plurality of mini light-emitting chips 3 are laid includes: providing a chip fixing film on which a predetermined classification of mini light-emitting chips 3 are laid, wherein the electrodes 31 of the mini light-emitting chips 3 face a side away from the chip fixing film. In fact, during the production process of the mini light-emitting chips 3, the mini light-emitting chips 3 are tested and sorted, and the sorted mini light-emitting chips 3 are usually arranged on the chip fixing film, and the electrodes 31 face a side away from the chip fixing film. For example, the aforementioned Fig. 9 In the example, the sorted mini light-emitting chips 3 are laid on the second chip fixing film 6, and the state of the second chip fixing film 6 can meet the requirements of this embodiment.

[0099] In some embodiments, Fig.12 The steps of transferring the mini light-emitting chip 3 to the temporary substrate 1 according to the test classification results include:

[0100] S401, enabling the transfer device to simultaneously pick up a plurality of mini light-emitting chips and transfer the picked up mini light-emitting chips to a temporary substrate;

[0101] S402, separating the transfer device from the mini light-emitting chip, and the mini light-emitting chip remains on the temporary substrate.

[0102] In the conventional process of mini light emitting chips 3, the mini light emitting chips 3 are picked up and placed individually by a transfer device such as a pick-up head 7. This embodiment uses a transfer device that can pick up multiple mini light emitting chips 3 at the same time, which can double the transfer efficiency.

[0103] In some embodiments, the transfer device includes a transfer stamp 9 made of polydimethylsiloxane (also known as PDMS). Exemplarily, the transfer stamp 9 can be formed with a concave-convex pattern, the convex pattern is arranged according to a predetermined rule, and there is stickiness on the convex pattern; through the convex pattern, multiple mini light-emitting chips 3 can be picked up onto the transfer stamp 9 at the same time. In practical applications, the transfer stamp 9 can pick up all the mini light-emitting chips 3 within a certain range, or selectively pick up part of the mini light-emitting chips 3 within a certain range, depending on factors such as the arrangement density of the mini light-emitting chips 3 and actual needs. In this embodiment, the layout of the mini light-emitting chips 3 picked up by the transfer device corresponds to the bonding layer 41 on the packaging substrate 4, that is, these mini light-emitting chips 3 can be in contact with the bonding layer 41 when they are transferred to the packaging substrate 4.

[0104] In some embodiments, Fig.13 The step of providing a chip fixing film on which a plurality of mini light-emitting chips 3 are laid comprises:

[0105] S501, providing a chip fixing film on which unsorted mini light-emitting chips are laid, wherein electrodes of the mini light-emitting chips face a side close to the chip fixing film;

[0106] S502, placing the chip fixing film and the temporary substrate opposite to each other;

[0107] S503, transferring the predetermined classified mini light-emitting chips on the chip fixing film to the temporary substrate, the mini light-emitting chips are bonded to the temporary substrate, and separated from the chip fixing film.

[0108] In some embodiments, see Fig.14 The above step S501, the step of providing a chip fixing film on which the unsorted mini light-emitting chips 3 are laid, specifically includes:

[0109] S5011, providing a wafer to be cut, the wafer comprising a substrate and an epitaxial layer, the epitaxial layer being made into a structure corresponding to a mini light-emitting chip;

[0110] S5012, disposing a first chip fixing film on a side of the substrate away from the epitaxial layer;

[0111] S5013, dividing the wafer into a plurality of mini light-emitting chips, wherein the electrode of each mini light-emitting chip faces a side away from the first chip fixing film;

[0112] S5014, a second chip fixing film is provided on a side of the mini light-emitting chip where the electrode is provided, and each mini light-emitting chip is bonded to the second chip fixing film;

[0113] S5015, removing the first chip fixing film to obtain a chip fixing film provided with unsorted mini light-emitting chips;

[0114] In some embodiments, the step of transferring the predetermined classified mini light-emitting chips 3 on the chip fixing film to the temporary substrate 1 includes: transferring the mini light-emitting chips 3 to the temporary substrate 1 by thorn crystal transfer. The thorn crystal transfer is not only efficient, but also enables the electrodes 31 of the mini light-emitting chips 3 on the carrier to be reversed during the transfer. In some implementations of the present application, combined with other steps, a more efficient manufacturing process can be achieved.

[0115] In some embodiments, the light-emitting module manufacturing method includes sorting the mini light-emitting chips 3 according to the test classification results; it should be noted that sorting specifically refers to transferring the mini light-emitting chips 3 of the same or similar classification to the same carrier according to the test classification results.

[0116] Before sorting the mini light-emitting chips 3, the mini light-emitting chips 3 are also inspected for appearance, and the mini light-emitting chips 3 with poor appearance are removed. When sorting the mini light-emitting chips 3, the mini light-emitting chips 3 are arranged according to the layout corresponding to the bonding layer 41 on the packaging substrate 4. That is, in this embodiment, the appearance inspection can be performed first, and then the sorting operation can be performed. Compared with the traditional method of removing the core particles with poor appearance after the sorting is completed, this can prevent the mini light-emitting chips 3 after sorting from having gaps in arrangement due to the removal of the core particles, which is conducive to the subsequent production.

[0117] The steps of the method for manufacturing the light emitting module of this embodiment will be further described below in conjunction with specific examples.

[0118] Example 1:

[0119] See also Fig.15 as well as Fig.16 The process of the light-emitting module manufacturing method of this example includes:

[0120] S601, providing a chip fixing film on which mini light-emitting chips of predetermined categories are laid;

[0121] In this example, the mini light-emitting chips 3 on the provided chip fixing film have been sorted, that is, these mini light-emitting chips 3 can be directly applied to the light-emitting module to be manufactured.

[0122] like Fig.16As shown in (a), in this example, the electrode 31 of the mini light-emitting chip 3 faces the side away from the chip fixing film. In fact, this example can directly use the mini light-emitting chips 3 after sorting in the traditional process, such as the step S302 mentioned above. When these mini light-emitting chips 3 are sorted to the second chip fixing film 6, they are arranged with the electrode 31 facing away from the chip fixing film.

[0123] Since the mini light-emitting chips 3 in this example have been sorted, the mini light-emitting chips 3 on the chip fixing film can be subsequently transferred to the temporary substrate 1 according to the test classification results by directly transferring the mini light-emitting chips 3 on the chip fixing film with the mini light-emitting chips 3 of the predetermined classification to the temporary substrate 1.

[0124] S602, performing appearance inspection on the mini light-emitting chip;

[0125] In this example, the sorted mini light-emitting chips 3 are subjected to appearance inspection, and defective chips therein are removed.

[0126] S603, enabling the transfer device to simultaneously pick up a plurality of mini light-emitting chips and transfer the picked up mini light-emitting chips to the temporary substrate;

[0127] like Fig.16 (b) Fig.16 (c) and Fig.16 As shown in (d), the transfer device of this example uses a transfer stamp 9, which can transfer the mini light-emitting chips 3 to the temporary substrate 1 with the adhesive layer 2 in batches at one time. The transfer stamp 9 of this example is made of polydimethylsiloxane material, and its adhesion to the mini light-emitting chip 3 is greater than the adhesion of the chip fixing film to the mini light-emitting chip 3. A concave and convex pattern can be made on the transfer stamp 9, wherein at least the convex pattern is sticky, and the mini light-emitting chip 3 can be picked up through the convex pattern. It should be understood that the pattern of the transfer stamp 9 also corresponds to the distribution arrangement of the bonding layer 41 on the packaging substrate 4, and it can accurately place multiple mini light-emitting chips 3 on the packaging substrate 4 and contact the bonding layer 41 at the same time. In this example, the adhesive layer 2 is made of a material that can reduce or release the viscosity under light, and accordingly, in order to facilitate the peeling of the temporary substrate 1, the temporary substrate 1 itself is made of a transparent material, such as glass.

[0128] The transfer stamp 9 has a fast transfer speed for the mini light-emitting chip 3. In some implementations, it can reach about 5KK / H, while the transfer speed of some die-bonding machines is 30-50K / H, and the transfer speed of the thorn crystal is about 100K / H. It can be seen that the transfer of the transfer stamp 9 makes the transfer speed of the mini light-emitting chip 3 to the temporary substrate 1 very fast, and the overall transfer effect of the mini light-emitting chip 3 is greatly improved.

[0129] Moreover, compared with the traditional light-emitting module manufacturing process, this example uses a transfer stamp 9 to directly transfer the mini light-emitting chip 3 after sorting to the temporary substrate 1 according to the required electrode 31 orientation, eliminating the film inversion process and the use of chip fixing film. In some production processes, the manufacturer may be equipped with production equipment for mini light-emitting chips 3 and also equipped with production equipment for micro light-emitting chips. In this example, the mini light-emitting chip 3 is transferred using a transfer device, so the chip film inversion equipment is no longer required, and the transfer device in the micro light-emitting chip is used for production. This allows the production equipment of different light-emitting chips to be used interchangeably in some implementation processes, thereby improving the utilization rate of the production equipment and in some cases reducing the purchase of some equipment, saving overall costs.

[0130] S604, laminating the temporary substrate and the packaging substrate relatively;

[0131] like Fig.16 As shown in (e), the temporary substrate 1 is arranged under the packaging substrate 4, and the side of the temporary substrate 1 provided with the mini light-emitting chip 3 is opposite to the side of the packaging substrate 4 provided with the bonding layer 41. In this process, the electrode 31 of the mini light-emitting chip 3 is aligned with the bonding layer 41 by including but not limited to a CCD (charge coupled device) visual alignment system. The temporary substrate 1 and the packaging substrate 4 are brought close together until the electrode 31 of the mini light-emitting chip 3 contacts the bonding layer 41.

[0132] S605, laser welding to bond the mini light-emitting chip to the packaging substrate;

[0133] like Fig.16 As shown in (f), the package substrate 4 in this example can be a glass substrate or a transparent PCB (Printed Circuit Board), and the bonding layer 41 can be melted by laser L, so that the mini light-emitting chip 3 is bonded to the package substrate 4. In practical applications, other methods can also be used to bond the mini light-emitting chip 3 to the package substrate 4, and this application does not limit this.

[0134] S606, peeling off the temporary substrate;

[0135] like Fig.16 As shown in (g), after the temporary substrate 1 is peeled off, the transferred mini light-emitting chip 3 remains on the packaging substrate 4 and can enter the subsequent manufacturing steps. The peeling method of the temporary substrate 1 can be determined according to the specific material or viscosity of the adhesive layer 2. In this example, the corresponding light is irradiated through the temporary substrate 1 to weaken or eliminate the viscosity of the adhesive layer 2, so that the temporary substrate 1 can be easily separated from the mini light-emitting chip 3.

[0136] Compared with the traditional manufacturing process of light-emitting modules using mini light-emitting chips 3, the light-emitting module manufacturing method of this example retains the sorting and the use of chip fixing film to carry the mini light-emitting chips 3, so that a light-emitting module with good consistency of chip photoelectric performance can be manufactured, and the chip fixing film can still be used as a carrier during the sorting and transportation processes to provide protection for the mini light-emitting chips 3 at a low cost. Furthermore, this example omits the step of film inversion and uses the technology of batch transfer of mini light-emitting chips 3, so that the overall manufacturing efficiency of the light-emitting module is improved.

[0137] Example 2:

[0138] In this example, the manufacturing process of the mini light emitting chip 3 can still be consistent with that in the related art. Different from the above examples and related art, after the wafer is manufactured, Fig.17 and Fig.18 , this example uses the following steps to make a light-emitting module:

[0139] S701, disposing a first chip fixing film on a side of the substrate away from the epitaxial layer;

[0140] The first chip fixing film 5 can be an ultraviolet irradiation tape or a blue film, which can be selected according to actual conditions.

[0141] S702, dividing the wafer into a plurality of mini light-emitting chips;

[0142] At this time, the mini light-emitting chips 3 on the first chip fixing film 5 are all unsorted. After the wafer is divided, these unsorted multiple independent mini light-emitting chips 3 are still fixed on the first chip fixing film 5, and the electrodes 31 of these mini light-emitting chips 3 face the side away from the first chip fixing film 5.

[0143] S703, perform performance and appearance inspection on the mini light-emitting chip;

[0144] The relevant performance of each mini light-emitting chip 3 is tested, and the mini light-emitting chips 3 with similar performance are classified into the same category. In this example, the mini light-emitting chips 3 are subjected to appearance inspection, and defective core particles are eliminated. It should be noted that in this example, the mini light-emitting chips 3 are subjected to appearance inspection before sorting, which can ensure that there will be no vacancies in the mini light-emitting chips 3 subsequently arranged on the temporary substrate 1, which is beneficial to the subsequent production.

[0145] S704, performing film inversion on the mini light-emitting chip;

[0146] like Fig.18As shown in (a), the second chip fixing film 6 is attached to the side of the mini light-emitting chip 3 provided with the electrode 31, and each mini light-emitting chip 3 is also bonded to the second chip fixing film 6. After the second chip fixing film 6 is set, the first chip fixing film 5 can be removed to complete the film inversion. At this time, the posture of the mini light-emitting chip 3 on the carrier is flipped, and the second chip fixing film 6 of the mini light-emitting chip 3 provided with the electrode 31 close to the carrier is obtained.

[0147] In this example, the mini light-emitting chip 3 is inverted and the orientation of the electrode 31 of the mini light-emitting chip 3 is adjusted, which can facilitate the subsequent process steps; this will enable the mini light-emitting chip 3 to adopt a more efficient crystal transfer method during the transfer to the temporary substrate 1.

[0148] S705, placing the chip fixing film and the temporary substrate opposite to each other;

[0149] The side of the second chip fixing film 6 provided with the mini light emitting chip 3 is arranged opposite to the side of the temporary substrate 1 provided with the adhesive layer 2 .

[0150] S706, transferring the mini light-emitting chips of the predetermined classification to the temporary substrate by means of thorn crystal transfer;

[0151] like Fig.18 As shown in (b), the mini light-emitting chip 3 is pushed onto the temporary substrate 1 by the ejector pin 10, so that the mini light-emitting chip 3 is adhered by the adhesive layer 2 on the temporary substrate 1. Different from the traditional crystal transfer, in this example, based on the test classification result, only the mini light-emitting chips 3 of the predetermined classification are transferred to the temporary substrate 1, and the remaining mini light-emitting chips 3 are not subjected to crystal transfer. That is to say, in this step S706, the mini light-emitting chips 3 are sorted, and the carrier of the sorted mini light-emitting chips 3 is no longer the chip fixing film, but the temporary substrate 1 with the adhesive layer 2.

[0152] It is understandable that during the process of the thorn crystal transfer, the mini light-emitting chips 3 are also arranged in a desired arrangement, and the mini light-emitting chips 3 are arranged on the temporary substrate 1 in a manner corresponding to the bonding layer 41 of the packaging substrate 4 .

[0153] After obtaining the temporary substrate 1 with the mini light-emitting chip 3 transferred thereto, the subsequent steps are the same as S604 to S606 and will not be repeated in this example. Compared with the traditional production process of the light-emitting module using the mini light-emitting chip 3, the light-emitting module production method of this example is that the mini light-emitting chip 3 after sorting is no longer supported by the chip fixing film, which also saves the use of the chip fixing film once. This example combines the sorting step with the step of transferring the mini light-emitting chip 3 to the temporary substrate 1, and there is no need to move the mini light-emitting chip 3 from the chip fixing film to the temporary substrate 1 after sorting. The process is more simplified, and the speed of the crystal transfer is faster than the traditional solid crystal method, which improves the overall production efficiency of the light-emitting module.

[0154] The light-emitting module manufacturing method illustrated in this embodiment improves the efficiency of transferring the mini light-emitting chip 3 to the packaging substrate 4, and in some examples, other transfer processes of the mini light-emitting chip 3 have higher efficiency, thereby improving the overall manufacturing efficiency of the light-emitting module. In addition, the light-emitting module manufacturing method of this example retains part of the traditional process of using the mini light-emitting chip 3 to manufacture the light-emitting module, and does not require large-scale replacement of equipment and processes, which can effectively control costs and put into use.

[0155] This embodiment also provides a light-emitting module, including a packaging substrate 4 and a mini light-emitting chip 3, wherein the mini light-emitting chip 3 is bonded to the packaging substrate 4 through the steps of the above-mentioned light-emitting module manufacturing method. When the light-emitting module of this embodiment is manufactured, the transfer efficiency of the mini light-emitting chip 3 to the packaging substrate 4 is higher, and in some implementation processes, it can also be manufactured more efficiently. The light-emitting module includes but is not limited to a display panel capable of displaying, or a light-emitting backplane providing a backlight source, and the like.

[0156] This embodiment also provides a light-emitting device, which includes the above-mentioned light-emitting module and a frame, wherein the light-emitting module is arranged on the frame, wherein the light-emitting module can be efficiently manufactured, thereby ensuring the production efficiency of the light-emitting device. Exemplarily, the light-emitting device can be an electronic device with a display function, including but not limited to a smart terminal, a watch, a computer, a display, etc. equipped with a display panel, or a light source device without a display function.

[0157] It should be understood that the application of the present application is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to this application.

Claims

1. A method for manufacturing a light emitting module, characterized in that: include: Providing a chip fixing film on which a plurality of mini light-emitting chips are laid; Obtaining a test classification result of the mini light-emitting chip; Transferring the mini light-emitting chips to a temporary substrate according to the test classification result, wherein the mini light-emitting chips on the temporary substrate all belong to a predetermined classification, and the electrodes of the mini light-emitting chips face a side away from the temporary substrate; The temporary substrate is placed opposite to the packaging substrate, and the mini light-emitting chips are transferred in batches from the temporary substrate to the packaging substrate. The transferred mini light-emitting chips are bonded to the packaging substrate and separated from the temporary substrate.

2. The method for manufacturing a light emitting module according to claim 1, characterized in that: The step of providing a chip fixing film on which a plurality of mini light-emitting chips are laid comprises: A chip fixing film on which the mini light emitting chips of the predetermined category are laid is provided, wherein electrodes of the mini light emitting chips face a side away from the chip fixing film.

3. The method for manufacturing a light emitting module according to claim 2, characterized in that: The step of transferring the mini light-emitting chip to the temporary substrate according to the test classification result comprises: The transfer device simultaneously picks up a plurality of the mini light-emitting chips and transfers the picked-up mini light-emitting chips to the temporary substrate; The transfer device is separated from the mini light-emitting chip, and the mini light-emitting chip remains on the temporary substrate.

4. The method for manufacturing a light emitting module according to claim 1, wherein: The step of providing a chip fixing film on which a plurality of mini light-emitting chips are laid comprises: Providing a chip fixing film on which the unsorted mini light-emitting chip is laid, wherein the electrode of the mini light-emitting chip faces a side close to the chip fixing film; placing the chip fixing film and the temporary substrate opposite to each other; The mini light emitting chips of predetermined categories on the chip fixing film are transferred to the temporary substrate, and the mini light emitting chips are bonded to the temporary substrate and separated from the chip fixing film.

5. The method for manufacturing a light emitting module according to claim 4, characterized in that: The step of providing a chip fixing film on which the unsorted mini light-emitting chips are laid comprises: Providing a wafer to be cut, wherein the wafer includes a substrate and an epitaxial layer, and the epitaxial layer is made into a structure corresponding to the mini light-emitting chip; Disposing a first chip fixing film on a side of the substrate away from the epitaxial layer; dividing the wafer into a plurality of the mini light-emitting chips, wherein the electrode of each of the mini light-emitting chips faces a side away from the first chip fixing film; A second chip fixing film is arranged on one side of the mini light emitting chip where the electrode is arranged, and each of the mini light emitting chips is bonded to the second chip fixing film; The first chip fixing film is removed to obtain the chip fixing film provided with the unsorted mini light-emitting chips.

6. The method for manufacturing a light emitting module according to claim 4, characterized in that: The step of transferring the mini light-emitting chips of predetermined classification on the chip fixing film to the temporary substrate comprises: The mini light-emitting chip is transferred to the temporary substrate by means of thorn crystal transfer.

7. The method for manufacturing a light emitting module according to claim 1, wherein: The light-emitting module manufacturing method includes sorting the mini light-emitting chips according to the test classification results; Before sorting the mini light-emitting chips, the method further includes performing appearance inspection on the mini light-emitting chips, and removing the mini light-emitting chips with poor appearance; When the mini light-emitting chips are sorted, the mini light-emitting chips are arranged according to a layout corresponding to the bonding layer on the packaging substrate.

8. The method for manufacturing a light emitting module according to any one of claims 1 to 7, characterized in that: The chip fixing film is an ultraviolet irradiation tape or a blue film.

9. A light emitting module, characterized in that: include: A packaging substrate and a mini light-emitting chip, wherein the mini light-emitting chip is bonded to the packaging substrate through the steps of the light-emitting module manufacturing method according to any one of claims 1 to 8.

10. A light emitting device, characterized in that: It comprises the light emitting module as claimed in claim 9 and a frame, wherein the light emitting module is arranged on the frame.

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