Chip structure with paramagnetic light-emitting element and manufacturing method thereof

Abstract

The present invention provides a chip structure with a paramagnetic light-emitting element and a method for manufacturing the same. The method comprises forming an epitaxial layer on a first substrate, performing a first etching process, and removing the first substrate after providing an insulating layer, a plurality of bonding pads, and a temporary substrate. A magnetic metal structure is then bonded to the top surface of the epitaxial layer, and the temporary substrate is removed. A second etching process and a cutting process are then performed to form a chip structure with the paramagnetic light-emitting element. The disclosed chip structure and its manufacturing method improve the soft magnetic properties of the original substrate, achieving better initial magnetic permeability and enabling automatic die flipping and alignment. This method not only effectively improves the conventional flip-chip bonding process but also complies with the industry's rapid mass transfer technology.

Description

Technical Field

[0001] The present invention relates to a process technology for manufacturing a chip with a paramagnetic light-emitting element, particularly a chip structure and manufacturing method thereof that can achieve automatic flipping and alignment through the magnetic force difference between the upper and lower layers of the substrate in the chip structure and can be applied to flip-chip bonding. Background Art

[0002] Micro LEDs (Micro LEDs) are an emerging technology resulting from the miniaturization and matrixing of LEDs. They enable the integration of high-density, microscopic LED arrays on a wafer, where each pixel can be addressed and individually driven. However, despite continued advancements in Micro LEDs, manufacturing costs remain high, hindering their commercialization. A key factor is the ongoing bottleneck in micro-assembly technology for mass transfer. Traditional methods rely solely on robotic arms to individually and repeatedly grip Micro LED chips and transfer them to substrates. This outdated approach is not only prohibitively expensive but also requires significant time and effort, a key bottleneck preventing the successful mass transfer of Micro LEDs. The high production time, labor, and costs associated with this approach hinder both production and cost.

[0003] Flip chip technology, also known as flip-chip packaging or flip-chip packaging, is a type of chip packaging technology. This packaging technology differs from traditional chip packaging methods, which typically place the chip on a substrate (chip pad) and connect the chip to the substrate's connection points using wire bonding. Flip chip packaging, on the other hand, adds bumps to the chip's connection points and then flips the chip over to directly connect the bumps to the substrate, hence its name. Because flip chip technology offers significantly more convenient interconnection with the substrate than other ball grid array (BGA) packaging technologies, it has become a mainstream packaging technology widely used in microprocessor packaging and other applications. Driven by the market's demand for flip chip technology, packaging companies generally offer a complete service offering from 8-inch and 12-inch wafer probing, bump growth, assembly, and final testing.

[0004] Generally speaking, because traditional methods for mass-transferring Micro LEDs have fewer connection points (bonding pads), flip-chip bonding typically requires additional process steps to flip the die. These additional steps are extremely complex and cumbersome in the mass-transferring Micro LED process, resulting in additional process steps, increased labor time, and increased costs. These are all challenges that existing technologies urgently need to overcome.

[0005] In view of this, considering the many shortcomings listed above, it is extremely necessary to adopt multi-faceted considerations. Summary of the Invention

[0006] To address the problems of conventional technologies, the present invention provides a chip structure with a paramagnetic light-emitting element and a method for manufacturing the same. This novel chip structure and method provide a paramagnetic light-emitting element with an initial magnetic permeability. This light-emitting element can be bonded to a circuit board via a flip-chip bonding process. This light-emitting element is then placed on the circuit board to form a vertical light-emitting diode die, which has the initial magnetic permeability. The chip structure produced by the present invention, due to its superior soft magnetic properties and initial magnetic permeability, successfully meets the industry's requirements for rapid mass transfer technology.

[0007] Furthermore, another object of the present invention is to provide a natural magnetic reversal effect, based on the paramagnetic nature of the epitaxial layer and the nickel-iron alloy layer in the light-emitting element. This magnetic difference allows each completed die to automatically flip even when the orientation is incorrect, achieving an optimized result of automatic flipping and alignment design when the flip chip is bonded to the circuit board. This automatic die reversal effect, when combined with the subsequent process of mass transfer of micro-LEDs, can omit the additional alignment steps required in the traditional flip chip bonding process and steps, thereby saving the tedious time and labor costs, and meeting the industry's demand for rapid mass transfer.

[0008] In view of the above, according to the method for manufacturing a chip structure having a paramagnetic light-emitting element disclosed in the present invention, the method for manufacturing a chip structure having a paramagnetic light-emitting element includes the following steps: first, providing a first substrate and forming an epitaxial layer on the first substrate. Then, performing a first etching process to form at least two cavities in the epitaxial layer. Providing an insulating layer, disposed on the epitaxial layer and filling the cavities. Then, at least one first bonding pad and two second bonding pads are disposed through the insulating layer, wherein each second bonding pad is disposed within a cavity. Then, after providing a temporary substrate on the insulating layer, the first substrate is removed, so that the first bonding pad and the second bonding pad are sandwiched between the epitaxial layer, the insulating layer, and the temporary substrate. Then, bonding a magnetic metal structure to the top surface of the epitaxial layer, and then removing the temporary substrate, wherein the magnetic metal structure has an initial magnetic permeability. Afterwards, a second etching process is performed on the insulating layer and the epitaxial layer. The second etching process ends at the top surface of the magnetic metal structure. Then, a cutting process is performed starting from the top surface of the magnetic metal structure to complete the cutting of the magnetic metal structure to form a chip structure with a paramagnetic light-emitting element.

[0009] Optionally, the first etching process and the second etching process may be a platform etching process, and the cutting process may be a cutter wheel cutting process, and the cutting accuracy of the cutter wheel is 10 μm.

[0010] According to an embodiment of the present invention, the chip structure having a paramagnetic light-emitting element can be automatically flipped and aligned to complete bonding to a circuit board through a flip-chip bonding process. By placing the chip structure on the circuit board, a vertical LED die can be further formed, and the formed vertical LED die has the aforementioned initial magnetic permeability. Therefore, the vertical LED die can conduct a microcurrent to the epitaxial layer through the initial magnetic permeability.

[0011] Furthermore, in one embodiment of the present invention, the magnetic metal structure includes at least one nickel-iron alloy layer (Invar). In another embodiment of the present invention, the magnetic metal structure may also include a nickel-iron alloy layer and a copper layer (Copper) disposed thereon. The nickel-iron alloy layer and the copper layer may be combined through cutting, vacuum heating, and grinding and polishing to achieve the magnetic metal structure disclosed herein having high thermal conductivity, low thermal expansion coefficient, and initial magnetic permeability.

[0012] On the other hand, according to another embodiment of the present invention, the present invention may also selectively set a debonding layer between the epitaxial layer and the magnetic metal structure, so that the magnetic metal structure is bonded to the top surface of the epitaxial layer through the debonding layer. In this further embodiment, the debonding layer may be, for example, a thermal debonding layer or a cold debonding layer. When the debonding layer is a thermal debonding layer, the chip structure with paramagnetic light-emitting elements formed by the present invention can be automatically flipped and aligned and bonded to the circuit board through the flip chip bonding process, and then the thermal debonding layer can be automatically peeled off by directly raising the ambient temperature to above 100°C, thereby quickly removing the magnetic metal structure. Alternatively, when the debonding layer is a cold debonding layer, the present invention may also choose to lower the ambient temperature to below -20°C, so that the cold debonding layer can be automatically peeled off, thereby quickly removing the magnetic metal structure.

[0013] Furthermore, the present invention also discloses a chip structure having a paramagnetic light-emitting element, comprising: a magnetic metal structure having an initial magnetic permeability; an epitaxial layer disposed on the magnetic metal structure, and having at least two cavities formed in the epitaxial layer; an insulating layer disposed on the epitaxial layer and filling the cavities; and a plurality of bonding pads penetrating the insulating layer and connected to the epitaxial layer at the bottom of the insulating layer to provide electrical conduction for external signals, wherein the bonding pads include at least one first bonding pad and two second bonding pads, each of the second bonding pads being disposed in a cavity.

[0014] According to the chip structure disclosed in the present invention, the magnetic metal structure comprises at least a nickel-iron alloy layer, and optionally a copper layer disposed on the nickel-iron alloy layer. Due to the magnetic force difference between the material of this innovative magnetic metal structure and the epitaxial layer, the paramagnetic property is generated. Based on this characteristic, the chip structure fabricated by the present invention can be directly flipped and aligned through a flip-chip bonding process, and then bonded to a circuit board via the bonding pads to provide electrical conductivity for external signals.

[0015] The following is a detailed description of specific embodiments with reference to the accompanying drawings, which will make it easier to understand the purpose, technical content, characteristics and effects achieved by the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 11. A schematic flow chart of the steps of a method for manufacturing a chip structure having a paramagnetic light-emitting element according to an embodiment of the present invention;

[0018] Figure 2A This is a schematic structural diagram corresponding to step S102 according to an embodiment of the present invention;

[0019] Figure 2B This is a structural diagram corresponding to step S104 according to an embodiment of the present invention;

[0020] Figure 2C This is a schematic structural diagram corresponding to step S106 according to an embodiment of the present invention;

[0021] Figure 2D This is a structural diagram corresponding to step S108 according to an embodiment of the present invention;

[0022] Figure 2E This is a structural diagram corresponding to step S110 according to an embodiment of the present invention;

[0023] Figure 2F This is a structural diagram corresponding to step S110 according to an embodiment of the present invention;

[0024] Figure 2G This is a structural diagram corresponding to step S112 according to an embodiment of the present invention;

[0025] Figure 2H This is a structural diagram corresponding to step S112 according to an embodiment of the present invention;

[0026] Figure 2I This is a schematic structural diagram corresponding to step S114 according to an embodiment of the present invention;

[0027] Figure 2J This is a schematic structural diagram corresponding to step S116 according to an embodiment of the present invention;

[0028] Figure 2K is a schematic diagram of a chip structure having a paramagnetic light-emitting element according to an embodiment of the present invention;

[0029] Figure 3A Schematic diagram of a magnetic metal structure including a nickel-iron alloy layer according to an embodiment of the present invention;

[0030] Figure 3B is a schematic structural diagram of a magnetic metal structure including a nickel-iron alloy layer and a copper layer according to another embodiment of the present invention;

[0031] Figure 4 A schematic diagram of a chip structure having a paramagnetic light-emitting element fabricated according to an embodiment of the present invention being flip-chip bonded to a circuit board;

[0032] Figure 5 A schematic diagram of a wafer including a plurality of dies undergoing mass transfer according to an embodiment of the present invention;

[0033] Figure 6 is a schematic diagram showing a magnetic metal structure bonded to the top surface of an epitaxial layer through a debonding layer according to another embodiment of the present invention;

[0034] Figure 7A A schematic structural diagram of a first welding pad and a second welding pad provided according to an embodiment of the present invention;

[0035] Figure 7B FIG. 4 is a schematic structural diagram of a first welding pad and a second welding pad provided according to another embodiment of the present invention.

[0036] Explanation of symbols:

[0037] 11 - cavity, 15 - chip structure with paramagnetic light-emitting element; 21 - first substrate, 22 - temporary substrate; 31 - first bonding pad, 32 - second bonding pad; 41 - solder joint; 50 - wafer, 51 - crystal grain, 52 - crystal grain, 53 - crystal grain;

[0038] 200-magnetic metal structure, 201-nickel-iron alloy layer, 203-copper layer, 202-epitaxial layer, 204-insulating layer; 400-circuit board, 600-debonding layer;

[0039] M1-first etching process, M2-second etching process, D1-cutting process;

[0040] S102, S104, S106, S108, S110, S112, S114, S116-steps. DETAILED DESCRIPTION

[0041] The above description of the present invention and the following embodiments are intended to demonstrate and explain the spirit and principles of the present invention and to provide further explanation of the scope of the present invention. The features, implementation, and efficacy of the present invention are now described in detail below with reference to the accompanying drawings.

[0042] In view of the various deficiencies of the aforementioned prior art, the present invention aims to provide a chip structure with paramagnetic light-emitting elements and a manufacturing method thereof. By fabricating vertical light-emitting diode (LED) chips on a substrate with initial magnetic permeability and preferred soft magnetic properties, the present invention can leverage the substrate's special soft magnetic properties and apply magnetic array adsorption technology to meet the needs of mass transfer of micro LEDs, thereby resolving the problems of conventional Micro LED manufacturing costs and excessively complex processes.

[0043] Furthermore, the present invention leverages the paramagnetic properties of the light-emitting element—the magnetic difference between the upper and lower layers of the substrate—to automatically flip each completed die even when oriented incorrectly, ensuring precise alignment of the die distribution. When flip-chip bonding is performed on an existing circuit board, the paramagnetic properties of the light-emitting element enable automatic die flipping and alignment, effectively avoiding the additional hours, labor, and high costs associated with traditional flip-chip bonding methods.

[0044] In view of this, first, please refer to the present invention Figure 1 As shown in FIG, it is a schematic flow chart of the steps of the manufacturing method of the chip structure with paramagnetic light-emitting elements according to an embodiment of the present invention. The manufacturing method disclosed in the present invention mainly includes steps S102, S104, S106, S108, S110, S112, S114 and S116 shown in the figure. For the detailed description of this manufacturing method, please refer to Figures 2A to 2K The structure and element symbols shown in the figure are described in detail below:

[0045] As in step S102 and Figure 2A As shown, the present invention first provides a first substrate 21 and forms an epitaxial layer 202 on the first substrate 21. Then, as shown in step S104 and Figure 2B As shown, a first etching process M1 is performed to form at least two cavities 11 in the epitaxial layer 202, wherein the first etching process M1 can be performed by a mesa etching to form the cavities 11 in the epitaxial layer 202 for subsequent placement of bonding pads. Figure 2C As shown, the present invention further provides an insulating layer 204 on the epitaxial layer 202, and the insulating layer 204 fills the aforementioned cavity 11. Then, as shown in step S108 and Figure 2D As shown, the present invention then provides at least one first bonding pad 31 and two second bonding pads 32, wherein each second bonding pad 32 is formed in a corresponding cavity 11. These bonding pads (including the first bonding pad 31 and the two second bonding pads 32) penetrate the insulating layer 204 and are electrically connected to the epitaxial layer 202 at the bottom of the insulating layer 204 to provide subsequent electrical conduction of external signals. According to an embodiment of the present invention, each second bonding pad 32 is symmetrically arranged on two different sides of the first bonding pad 31. For example, when used in a semiconductor process, the first bonding pad 31 and the second bonding pad 32 can be used as contact pads for electrical conduction between a P-type semiconductor (P-type) and an N-type semiconductor (N-type), respectively, to provide subsequent back-end processes such as wire bonding for electrical routing.

[0046] Then, as in step S110 and Figure 2E As shown, the present invention further provides a temporary substrate 22 on the insulating layer 204, and then, as shown in FIG. Figure 2F As shown, the first substrate 21 is removed. The first and second bonding pads 31 and 32 are now sandwiched between the epitaxial layer 202, the insulating layer 204, and the temporary substrate 22. According to an embodiment of the present invention, the first substrate 21 can be removed, for example, by a laser step or etching process. The laser referred to herein is not limited to conventional laser wavelengths or to more accurate picosecond or femtosecond lasers. For example, if the resulting light-emitting element is a diode that emits blue or green light, the first substrate 21 can be removed by laser. If the resulting light-emitting element is a diode that emits red light, the first substrate 21 can be removed by etching. Generally speaking, those skilled in the art can modify or adjust the design based on the actual product specifications and application requirements. However, equivalent variations based on the principles disclosed herein are still within the scope of the present invention.

[0047] Afterwards, as described in step S112, the present invention Figure 2G As shown, a magnetic metal structure 200 is bonded to the top surface of the epitaxial layer 202. The magnetic metal structure 200 used in the present invention is conceived by the applicant through innovative thinking and special design. Its characteristics are: based on its special substrate properties, this magnetic metal structure 200 can have better soft magnetic properties and initial magnetic permeability than traditional substrates. Under these conditions, its structure itself can serve as an effective magnetic permeability structure. As long as it is combined with magnetic equipment, such as a tiny magnetic probe, it can be combined with the principle of magnetic array adsorption in subsequent processes to achieve one-time and large-scale adsorption. When applied to industrial mass transfer, it can achieve excellent results. Figure 3A and Figure 3B According to the magnetic metal structure 200 disclosed in the present invention, there are two feasible implementations, such as Figure 3A As shown, the magnetic metal structure 200 comprises at least a nickel-iron alloy layer 201, or Figure 3BAs shown, the magnetic metal structure 200 may include a nickel-iron alloy layer 201 and a copper layer 203 located on the nickel-iron alloy layer 201. The nickel-iron alloy layer 201 used may be, for example, a nickel-iron alloy containing 36% nickel. The copper layer 203 located on the nickel-iron alloy layer 201 can be used for further spot testing of the chip in the future. Based on the nickel-iron alloy layer 201 and the copper layer 203 disclosed in the present invention, they can be combined by cutting, vacuum heating, and grinding and polishing, so that the formed magnetic metal structure 200 not only has initial magnetic permeability, but also has high thermal conductivity and low thermal expansion coefficient. In the subsequent wire bonding packaging process, it can naturally provide a better production yield. Compared to other conventional metal substrates, the magnetic metal structure 200 disclosed in the present invention is sufficiently thin and transparent, thereby providing excellent low thermal expansion coefficient and high thermal conductivity without the need for additional thinning processes. It also has the advantages of low cost, high yield, and easier bonding to epitaxial layers. Compared to conventional technologies, it is clearly a more competitive new substrate option in the industry today.

[0048] Afterwards, Figure 2H As shown, the temporary substrate 22 is removed. Then, step S114 is performed. Figure 2I As shown, the present invention performs a second etching process M2 based on the insulating layer 204 and the epitaxial layer 202, wherein the second etching process M2 can also be performed by a mesa etching, and the second etching process M2 is controlled to terminate at the top surface of the magnetic metal structure 200. After the etching is completed, as shown in steps S116 and Figure 2J As shown, starting from the top surface of the magnetic metal structure 200, a cutting process D1 is subsequently performed to complete the cutting of the magnetic metal structure 200. After the cutting process D1 is completed, the following is formed: Figure 2K A chip structure 15 having a paramagnetic light-emitting element is provided.

[0049] It is worth noting that if Figure 2I and Figure 2J As shown, it can be seen that the cutting width of the second etching process M2 designed in the present invention is slightly wider than the cutting width of the cutting process D1. Secondly, considering that the traditional cutting method may have defects such as mechanical damage, the cutting process D1 described in the embodiment of the present invention is carried out by cutting with a single knife wheel, and its accuracy can reach 10 microns. In one embodiment, it is estimated that the cutting time of a single knife can be controlled within one hour, and after the cutting process is completed, a magnetic metal structure with a size suitable for the micron (μm) level, for example, a size of less than 100 μm, is provided, which is in line with the current trend of miniaturization of light-emitting components in the industry.

[0050] Therefore, the present applicant has manufactured a chip structure 15 having a paramagnetic light-emitting element through the above-mentioned manufacturing method and the steps disclosed therein, such as Figure 2K As shown, it includes: a magnetic metal structure 200 having an initial magnetic permeability; an epitaxial layer 202 disposed on the magnetic metal structure 200, and at least two cavities 11 are formed in the epitaxial layer 202; an insulating layer 204 disposed on the epitaxial layer 202 and filling the cavities 11; and at least one first bonding pad 31 and two second bonding pads 32, which penetrate the insulating layer 204 and connect to the epitaxial layer 202 at the bottom of the insulating layer 204 to provide electrical conduction of external signals, wherein each of the second bonding pads 32 is disposed in a corresponding cavity 11. According to the technical solution disclosed in the present invention, this chip structure 15 having a paramagnetic light-emitting element is suitable for flip chip bonding to a printed circuit board (PCB). Please refer to Figure 4 , which is a schematic diagram of a chip structure 15 manufactured according to an embodiment of the present invention being bonded to a circuit board 400 via a flip chip. Figure 5 As shown, when a wafer 50 has, for example, more than 80,000 dies, and each die includes a chip structure with a paramagnetic light-emitting element disclosed in the present invention, in this case, when a carrier or a robot arm with a magnetic probe picks up the dies 51, 52, 53 and places them on the circuit board 400, from the perspective of a single die (corresponding to a chip structure 15 with a paramagnetic light-emitting element), as shown in FIG. Figure 4 As shown, in this case, given that there is a certain magnetic force difference between the epitaxial layer 202 and the nickel-iron alloy layer contained in the magnetic metal structure 200, based on the magnetic force difference between the upper and lower layers of the chip structure 15, each completed chip structure 15 can achieve the effect of automatic flipping even when the direction is wrong, so that the epitaxial layer 202 can automatically flip downward and complete the bonding to the circuit board 400 through the first bonding pad 31 and the second bonding pad 32 and their corresponding conductive bumps or solder joints 41, so as to provide electrical conduction of external signals in the future. Even after the flip-chip bonding is completed, the magnetic metal structure 200 can be removed through the back-end process. Afterwards, the present invention can form a vertical LED chip by setting the chip structure 15 on the circuit board 400, so that the vertical LED chip has a better initial magnetic permeability, and the vertical LED chip can conduct a microcurrent through the epitaxial layer 202 through this initial magnetic permeability. After the vertical LED chips formed according to the present invention are subsequently assembled into modules, they can not only have the wireless power generation function, but also achieve new applications of wireless lighting, thereby fully meeting the application requirements of high-power LEDs.

[0051] In one embodiment, when the selected circuit board 400 is a thin film transistor liquid crystal display panel (TFT), the present invention can also successfully implement the mass transfer micro-assembly technology in the Micro LED display panel structure.

[0052] Therefore, in summary, based on the chip structure with paramagnetic light-emitting elements disclosed in the present invention, it has better soft magnetic properties than the existing technology, so that the grains themselves can serve as magnetic permeability structures. When this magnetic force is transferred to the circuit board in a large amount, combined with the above-mentioned automatic reversal effect of the grains, by grounding its upper electrode, the circuit board controls its voltage level through the integrated circuit (IC) chip, and thus the luminous intensity of each grain can be individually controlled. When it is subsequently integrated into the display panel, the purpose of controlling the luminescence of the display panel partitions or controlling its different luminous intensities is achieved, effectively enhancing the competitiveness of the technical solution disclosed in the present invention in industrial development.

[0053] At the same time, the chip structure with paramagnetic light-emitting elements disclosed in the present invention and its manufacturing method can also have the characteristic of automatic reversal due to the paramagnetism of the grains themselves. Through this characteristic, the alignment of the distribution position of the grains during subsequent flip-chip bonding can be achieved accurately. The paramagnetism is formed by a certain magnetic difference between the epitaxial layer and the nickel-iron alloy layer in this light-emitting element. This paramagnetism can enable each completed grain to achieve the effect of automatic flipping and automatic alignment even when the direction is incorrect. Through this feature, the present invention also greatly avoids the problems of excessively high operating hours, manpower, and costs that must be borne during traditional flip-chip bonding, providing the optimization advantage of the present invention.

[0054] On the other hand, Figure 6 A schematic structural diagram of another embodiment of the present invention is disclosed. As shown in the figure, according to another embodiment of the present invention, in the step of bonding the magnetic metal structure 200 on the top surface of the epitaxial layer 202, a debonding layer 600 may be optionally provided so that the debonding layer 600 is formed between the epitaxial layer 202 and the magnetic metal structure 200. Thus, the magnetic metal structure 200 is bonded to the top surface of the epitaxial layer 202 through the debonding layer 600. In this way, when the structure is subsequently bonded to the top surface of the epitaxial layer 202, Figure 1 The steps S112 to S116 are used to form a chip structure having a paramagnetic light emitting element, and the chip structure is formed by Figure 4The flip chip bonding process automatically flips the chip into position and completes bonding to the circuit board. Then, the release layer 600 can be directly peeled off by changing the ambient temperature, thereby easily removing the magnetic metal structure 200. According to one embodiment of the present invention, the release layer 600 can be, for example, a thermal release layer or a thermal release film. In this embodiment, the thermal release layer can be peeled off at a specific release temperature and time. The present invention can increase the ambient temperature to above 100°C, causing the thermal release layer to lose its viscosity and automatically peel off. In this way, the present invention can effectively omit the commonly known steps of chemical etching or physical removal, and easily remove the magnetic metal structure in a simpler manner without damaging the chip structure. This is another advantage of the present invention.

[0055] On the other hand, the debonding layer 600 is not limited to a thermal debonding layer. In another embodiment of the present invention, the debonding layer 600 may also be a cold debonding layer or cold debonding film. In this case, the cold debonding layer can also be peeled off at a specific debonding temperature and time. The present invention also allows the cold debonding layer to lose its stickiness and automatically peel off by lowering the ambient temperature to below -20°C. Similarly, the magnetic metal structure can be easily removed under relatively simple conditions without damaging the chip structure.

[0056] Furthermore, for the present invention Figure 1 In the disclosed step S108, when forming the aforementioned solder pads, the configuration shape and size of the solder pads are not limited. For example, Figure 7A and Figure 7B The first and second pads disclosed in the present invention have two feasible implementation modes. The figure shows a top view of the pads. The shape of the first pad 31 can be, for example, Figure 7A The circle shown or Figure 7B The shape of the second pad 32 can be, for example, Figure 7A The polygonal arc or Figure 7B The polygonal shape shown. However, each second pad 32 is symmetrically arranged on opposite sides of the first pad 31 and is equidistant from the first pad 31. Therefore, based on the several embodiments disclosed herein and the technical concepts taught therein, those skilled in the art can freely vary the design in actual implementation, and all such variations fall within the scope of the present invention. The several exemplary embodiments listed in the preceding paragraphs are intended to explain the main technical features of the present invention and enable those skilled in the art to understand and implement them accordingly. However, the present invention is not limited to these exemplary embodiments.

[0057] Therefore, in view of the above, it is obvious that the present invention discloses a chip structure with a paramagnetic light-emitting element and its manufacturing method. Because the present invention improves the substrate structure and material of the original grain, it has better soft magnetic properties and initial magnetic permeability, so that the light-emitting element itself can serve as a magnetic permeability structure. By combining it with a magnetic device, such as a tiny magnetic probe, the principle of magnetic array adsorption can be utilized to absorb a large number of these soft magnetic light-emitting diode grain structures at one time, achieving the effect of rapid and mass transfer. This meets the current requirements of rapid and mass transfer technology for Micro LEDs and effectively enhances the competitiveness of its industrial production.

[0058] At the same time, an important effect of the present invention is to provide a natural magnetic reversal effect. Based on the certain magnetic difference between the epitaxial layer and the nickel-iron alloy layer in this light-emitting element, this magnetic difference forms the aforementioned paramagnetism. Through this special paramagnetic property, the present invention enables each completed chip structure to achieve the function of automatic flipping when it is subsequently flip-chip bonded to the circuit board, even if the direction is incorrect, so that the chip structure can automatically flip and align and complete the bonding to the circuit board, thereby achieving an optimized result of automatic proofreading and automatic alignment design, meeting the industry's needs for rapid and large-scale transfer. Through this inventive concept, the present invention also greatly saves the additional alignment operation steps and time-consuming and manpower-consuming problems required when traditional flip-chip bonding is used. It is obvious that the technical solution disclosed by the present invention does have excellent industrial applicability and competitiveness. At the same time, it is verified that the technical features, methods and means disclosed by the present invention and the effects achieved are significantly different from the existing solutions, and in fact, it is not easy for those familiar with the technology to accomplish.

[0059] The embodiments described above are merely illustrative of the technical concepts and features of the present invention. Their purpose is to enable persons skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the patent scope of the present invention. In other words, any equivalent changes or modifications made in accordance with the spirit disclosed in the present invention should still be covered by the patent scope of the present invention.

Claims

1. A method for manufacturing a chip structure having a paramagnetic light-emitting element, suitable for flip-chip bonding to a circuit board. The flip-chip bonding process automatically flips and aligns the formed chip structure and bonds it to the circuit board to provide electrical conduction of external signals. The method is characterized in that: The manufacturing method comprises: Providing a first substrate and forming an epitaxial layer on the first substrate; performing a first etching process to form at least two cavities in the epitaxial layer; providing an insulating layer disposed on the epitaxial layer and filling the cavities; At least one first welding pad and two second welding pads are disposed through the insulating layer, and each of the second welding pads is disposed in one of the cavities; Disposing a temporary substrate on the insulating layer, and removing the first substrate so that the first bonding pad and the second bonding pads are sandwiched between the epitaxial layer, the insulating layer and the temporary substrate; Bonding a magnetic metal structure on the top surface of the epitaxial layer and removing the temporary substrate, wherein the magnetic metal structure has an initial magnetic permeability; performing a second etching process on the insulating layer and the epitaxial layer, wherein the second etching process is terminated at the top surface of the magnetic metal structure; and Starting from the top surface of the magnetic metal structure, a cutting process is subsequently performed to complete the cutting of the magnetic metal structure to form a chip structure with a paramagnetic light-emitting element.

2. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 1, characterized in that: The magnetic metal structure at least includes a nickel-iron alloy layer.

3. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 1, wherein: The magnetic metal structure includes a nickel-iron alloy layer and a copper layer located on the nickel-iron alloy layer.

4. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 3, characterized in that: The nickel-iron alloy layer and the copper layer are combined by cutting, vacuum heating, grinding and polishing, so that the magnetic metal structure has high thermal conductivity, low thermal expansion coefficient and the initial magnetic permeability.

5. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 1, wherein: The step of bonding the magnetic metal structure to the top surface of the epitaxial layer further comprises: disposing a debonding layer between the epitaxial layer and the magnetic metal structure, so that the magnetic metal structure is bonded to the top surface of the epitaxial layer through the debonding layer.

6. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 5, characterized in that: When the debonding layer is a thermal debonding layer, the manufacturing method of the chip structure having the paramagnetic light-emitting element further includes: The ambient temperature is raised to above 100° C. to peel off the pyrolytic adhesive layer and remove the magnetic metal structure.

7. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 5, characterized in that: When the debonding layer is a cold debonding layer, the manufacturing method of the chip structure having the paramagnetic light-emitting element further includes: The ambient temperature is lowered to below -20°C to peel off the cold-debonding layer and remove the magnetic metal structure.

8. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 1, wherein: The cutting process is a cutter wheel cutting process, and the cutting accuracy of the cutter wheel is 10μm.

9. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 1, wherein: Each of the second bonding pads is symmetrically disposed on two different sides of the first bonding pad.

10. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 1, wherein: The first etching process is performed by a platform etching.

11. The method for manufacturing a chip structure having a paramagnetic light-emitting element according to claim 1, wherein: The second etching process is performed by a platform etching.

12. A chip structure having a paramagnetic light-emitting element, suitable for flip-chip bonding to a circuit board, wherein the flip-chip bonding process automatically flips the formed chip structure to align and bond to the circuit board to provide electrical conduction of external signals, characterized in that: The chip structure having a paramagnetic light-emitting element is manufactured using the method for manufacturing a chip structure having a paramagnetic light-emitting element according to any one of claims 1 to 11, and the chip structure having a paramagnetic light-emitting element comprises: A magnetic metal structure having an initial magnetic permeability; an epitaxial layer disposed on the magnetic metal structure, wherein at least two cavities are formed in the epitaxial layer, wherein the openings of the cavities face upward; an insulating layer disposed on the epitaxial layer and filling the cavities; and A plurality of solder pads penetrate the insulating layer and are connected to the epitaxial layer at the bottom of the insulating layer. The solder pads include at least one first solder pad and two second solder pads. Each of the second solder pads is disposed in one of the cavities, wherein the opening of each of the cavities faces upward so as to accommodate the solder pads through the cavities with the openings facing upward. The invention is characterized in that the magnetic force difference in the magnetic metal structure forms a paramagnetism, and through the paramagnetism, the chip structure can be automatically flipped, and when the chip structure is aligned, it is connected to the circuit board through the solder pads to provide electrical conduction of external signals.

13. The chip structure having a paramagnetic light-emitting element according to claim 12, characterized in that: Each of the second bonding pads is symmetrically disposed on two different sides of the first bonding pad.

14. The chip structure having a paramagnetic light-emitting element according to claim 12, characterized in that: The chip structure with the paramagnetic light-emitting element further includes a debonding layer, which is arranged between the epitaxial layer and the magnetic metal structure, so that the magnetic metal structure is bonded to the epitaxial layer through the debonding layer.

15. The chip structure having a paramagnetic light-emitting element according to claim 12, characterized in that: The magnetic metal structure at least includes a nickel-iron alloy layer.

16. The chip structure having a paramagnetic light-emitting element according to claim 12, characterized in that: The magnetic metal structure includes a nickel-iron alloy layer and a copper layer located on the nickel-iron alloy layer.

17. The chip structure having a paramagnetic light-emitting element according to claim 16, characterized in that: The nickel-iron alloy layer and the copper are combined by cutting, vacuum heating, grinding and polishing, so that the magnetic metal structure has high thermal conductivity, low thermal expansion coefficient and the initial magnetic permeability.

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