Structure of LED chip capable of emitting blue-green light
By alternately setting the structure of blue and green multi-quantum well layers in the LED chip, the problem of small color gamut coverage of traditional blue LED chips is solved, and wider color gamut coverage and stronger color expression is achieved.
Patent Information
- Application Number
- CN202421217171.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-30
- Publication Date
- 2025-04-29
- Estimated Expiration
- 2034-05-30
AI Technical Summary
Traditional blue light LED chips have a small color gamut coverage, which is difficult to meet the market's demand for a wide color gamut.
An LED chip structure including a multi-quantum well layer is adopted, which consists of a substrate, a multi-quantum well layer, a P-type GaN layer and an N-type GaN layer. A blue-light multi-quantum well layer and a green-light multi-quantum well layer are alternately arranged in the multi-quantum well layer to achieve effective emission of blue-green light.
By broadening the color gamut coverage of the LED chip, the color expressiveness is enhanced and the components in the phosphor that contribute more to green and red can be more effectively stimulated, thereby significantly expanding the color gamut range of the LED.
Smart Images
Figure CN222814789U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of LED chips, in particular to a structure of an LED chip capable of emitting blue-green light. Background Art
[0002] LED (Light Emitting Diode) is a solid-state semiconductor device that can convert electrical energy into light energy. It has the advantages of low power consumption, good focusing effect, fast response speed, strong controllability, ability to withstand high impact, long service life, and environmental protection. LED is gradually replacing traditional light sources and becoming the fourth generation of light sources. For LED packaging devices, different packaging structures will have a relatively large impact on LEDs, such as affecting life, luminous angle, color gamut, etc.
[0003] With the rapid development of social economy, consumers' requirements for the color expression of LEDs are increasing. Most existing LED chips use blue light to excite phosphors, but their color gamut coverage is relatively limited, making it difficult to fully meet the market demand for a wide color gamut.
[0004] The purpose of the utility model is to solve the problem that the color gamut coverage of traditional blue light LED chips is small. Utility Model Content
[0005] The purpose of the utility model is to solve the problem of small color gamut coverage of traditional blue light LED chips. The utility model adopts the following technical solutions:
[0006] A structure of an LED chip capable of emitting blue-green light comprises a substrate, wherein the substrate serves as a basic platform and a physical support platform for the growth of an LED chip device, a multi-quantum well layer is arranged on the top surface of the substrate, the multi-quantum well layer comprises a plurality of blue light multi-quantum well layers and a plurality of green light multi-quantum well layers, a P-type GaN layer is arranged above the multi-quantum well layer, an N-type GaN layer is arranged below the multi-quantum well layer, the N-type GaN layer serves to provide electrons, the P-type GaN layer serves to provide holes, and the P-type GaN layer and the N-type GaN layer together form a PN junction.
[0007] In the structure of the LED chip capable of emitting blue-green light as described above, the blue light multi-quantum well layer and the green light multi-quantum well layer are both composed of an InGaN barrier layer and an InGaN well layer.
[0008] As described above, in the structure of an LED chip capable of emitting blue-green light, the thickness of the InGaN barrier layer of the green light multi-quantum well layer is 5-25nm, the In content is 20%-85%, the emission wavelength is 515-550nm, and the thickness of the InGaN well layer of the green light multi-quantum well layer is 1-7nm, and the In content is 1%-25%.
[0009] As described above, in the structure of an LED chip capable of emitting blue-green light, the thickness of the InGaN barrier layer of the blue light multi-quantum well layer is 5-25nm, the In content is 10%-40%, the emission wavelength is 440-470nm, and the thickness of the InGaN well layer of the blue light multi-quantum well layer is 1-7nm, and the In content is 1%-25%.
[0010] In the structure of the LED chip capable of emitting blue-green light as described above, a plurality of the blue light multi-quantum well layers and a plurality of the green light multi-quantum well layers 52 are alternately stacked.
[0011] In the structure of the LED chip capable of emitting blue-green light as described above, a non-doped GaN layer is disposed below the N-type GaN layer, and the thickness of the non-doped GaN layer is 0.5-3 μm.
[0012] In the structure of the LED chip capable of emitting blue-green light as described above, a GaN buffer layer is provided between the undoped GaN layer and the substrate, and the thickness of the GaN buffer layer is 20-40 nm.
[0013] In the structure of the LED chip capable of emitting blue-green light as described above, the total number of the multi-quantum well layers is at least layers, including a blue light multi-quantum well layer and a green light multi-quantum well layer.
[0014] In the structure of the LED chip capable of emitting blue-green light as described above, the material of the substrate is one of sapphire, silicon or gallium nitride.
[0015] In the structure of the LED chip capable of emitting blue-green light as described above, the thickness of the N-type GaN layer is about 0.5-5 μm, and the doping concentration of Si is greater than 1018 / cm 3 The thickness of the P-type GaN layer is about 50-250 nm, and the Mg doping concentration is greater than 1018 / cm 3 .
[0016] Implementing the embodiments of the utility model has the following beneficial effects:
[0017] In the utility model, a blue light multi-quantum well layer and a green light multi-quantum well layer are arranged in the multi-quantum well layer, which realizes the effective emission wavelength coverage of blue and green light, broadens the color gamut coverage of the LED chip, and thus enhances the color expression.
[0018] In summary, the utility model solves the problem of small color gamut coverage of traditional blue light LED chips. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0020] Figure 1 The utility model is a schematic structural diagram of an LED chip capable of emitting blue-green light.
[0021] Figure 2 The utility model is a schematic diagram of the structure of a multi-quantum well layer of an LED chip capable of emitting blue-green light. DETAILED DESCRIPTION
[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0023] like Figure 1 to Figure 2As shown, the embodiment of the utility model proposes a structure of an LED chip capable of emitting blue-green light, comprising a substrate 1, wherein the function of the substrate 1 is to serve as a basic platform and a physical support platform for the growth of LED chip devices, a multi-quantum well layer 5 is arranged on the top surface of the substrate 1, and the multi-quantum well layer 5 comprises a plurality of blue light multi-quantum well layers 51 and a plurality of green light multi-quantum well layers 52, a P-type GaN layer 6 (hole-type gallium nitride layer) is arranged above the multi-quantum well layer 5, and an N-type GaN layer 4 (electron-type gallium nitride layer) is arranged below the multi-quantum well layer 5, the function of the N-type GaN layer 4 is to provide electrons, the function of the P-type GaN layer 6 is to provide holes, and the P-type GaN layer 6 and the N-type GaN layer 4 together form a PN junction. The substrate 1 serves as the foundation and supporting platform of the LED chip, and provides a stable base for the LED chip to epitaxially grow other semiconductor layers. The N-type GaN layer 4 and the P-type GaN 6 layer together constitute the PN junction in the LED. The N-type GaN 4 layer introduces excess electrons by doping with silicon Si elements, becoming the source of electrons. The P-type GaN layer introduces a state of lacking electrons, i.e., holes, by doping with magnesium Mg, becoming a positive charge carrier. When the LED chip is powered on, electrons and holes are injected from the P-type layer and the N-type layer into the multi-quantum well region respectively under the action of the electric field. When electrons and holes recombine in the multi-quantum well layer 5, electrons jump from the conduction band to the valence band to fill the holes, and at the same time, excess energy is released in the form of photons. Since the band gap width of the InGaN material varies with the In (indium) content, the different In contents of the blue multi-quantum well layer 51 and the green multi-quantum well layer 52 can make the quantum well layer emit light of a specific wavelength. The blue light quantum well layer contains a lower proportion of In and emits blue light with a wavelength in the range of 440-470nm; while the green light quantum well layer contains a higher proportion of In and emits light with a wavelength in the range of 515-550nm, i.e. green light. Through this process, blue light and green light are simultaneously generated and emitted from the LED chip. These lights can be used directly or converted into other colors such as white light through phosphors, suitable for various lighting and display applications. Unlike relying solely on blue light LEDs, blue-green light LED chips can output a spectrum containing more green light components. This spectral structure can more effectively excite the components in the phosphors that contribute more to green and red, thereby significantly expanding the color gamut of the LED.
[0024] Furthermore, as a preferred embodiment of the present invention but not a limitation, the material of the substrate 1 is sapphire, silicon or gallium nitride. Optionally, in some embodiments, the material of the substrate 1 is sapphire. Sapphire substrate has extremely high chemical stability and thermal stability, and is suitable for high temperature environments during LED growth.
[0025] Optionally, in some embodiments, the substrate 1 is made of silicon, which is the most commonly used material in the semiconductor industry, with high output and low cost. The thermal conductivity of silicon is better than that of sapphire, which helps to improve the heat dissipation performance of the LED.
[0026] Optionally, in some embodiments, the substrate 1 is made of gallium nitride, and the gallium nitride substrate has a high lattice matching degree with the gallium nitride epitaxial layer, and can grow a high-quality epitaxial film, greatly reducing the dislocation density and improving the device performance.
[0027] Further, as a preferred embodiment of the present invention but not a limitation, the blue light multi-quantum well layer 51 and the green light multi-quantum well layer 52 are both composed of an InGaN barrier layer and an InGaN well layer. The thickness of the InGaN barrier layer of the green light multi-quantum well layer 52 is 5-25nm, the In content is 20%-85%, and the emission wavelength is 515-550nm, covering the green light region, thereby enhancing the green expression of the LED chip and broadening the overall color gamut. The thickness of the InGaN well layer of the green light multi-quantum well layer is 1-7nm, and the In content is 1%-25%, aiming to optimize the emission efficiency of green light, while ensuring good electronic structure matching with the barrier layer and promoting effective transitions between energy levels. The thickness of the InGaN barrier layer of the blue light multi-quantum well layer 51 is 5-25nm, the In content is 10%-40%, and the emission wavelength is 440-470nm. Blue light is the basic light source of LED and provides efficient energy for subsequent phosphor excitation. The thickness of the InGaN well layer of the blue light multi-quantum well layer 51 is 1-7nm, and the In content is 1%-25%, which corresponds to the well layer design in the green light multi-quantum well layer 52 to optimize the emission efficiency of blue light and the overall performance of the device.
[0028] Further, as a preferred embodiment of the present invention but not a limitation, a plurality of the blue multi-quantum well layers 51 and a plurality of the green multi-quantum well layers 52 are stacked alternately. By alternately arranging the blue and green multi-quantum well layers in the structure, not only can efficient emission of each band be obtained, but also the fine tuning and expansion of the spectrum can be achieved through the superposition effect of the two. Alternating stacking of multi-quantum well layers of different wavelengths helps to improve the absorption and conversion efficiency of light. The blue light layer is responsible for the basic high-intensity excitation, and the green light layer supplements and adjusts the color temperature. The synergistic effect of the two not only ensures high brightness output, but also makes the color distribution more uniform and natural, reducing color deviation.
[0029] Optionally, in some embodiments, a plurality of the blue multi-quantum well layers 51 and a plurality of the green multi-quantum well layers 52 are stacked in groups, that is, all the blue multi-quantum well layers 51 are stacked first and then all the green multi-quantum well layers 52 are stacked, or all the green multi-quantum well layers 52 are stacked first and then all the blue multi-quantum well layers 51 are stacked. Group stacking simplifies the manufacturing process steps, avoids the complex and precise control required in the alternating deposition process of quantum well layers of different wavelengths, reduces the manufacturing difficulty and cost, and improves production efficiency. Since the interface properties between similar quantum well layers are similar, group stacking is conducive to reducing interface defects and improving the internal consistency of the device, thereby improving the overall photoelectric conversion efficiency and reliability.
[0030] Optionally, in some embodiments, a plurality of the blue light multi-quantum well layers 51 and a plurality of the green light multi-quantum well layers 52 are randomly stacked. The random stacking may cause the spectral output to have a certain randomness, which may be regarded as an advantage in certain specific applications, such as simulating the complex spectral changes of natural light, or creating more natural and irregular light and shadow effects in certain lighting applications.
[0031] Furthermore, as a preferred embodiment of the present invention but not a limitation, an undoped GaN layer 3 is provided below the N-type GaN layer 4, and the thickness of the undoped GaN layer 3 is 0.5-3 μm. As a lattice matching layer, the undoped GaN layer 3 can effectively alleviate the mismatch stress caused by the difference in lattice constants between different materials, such as sapphire or silicon substrates and GaN, reduce the dislocation density, and thus improve the overall crystal quality and reliability of the device. As a barrier layer between the N-type GaN layer 4 and the substrate 1, the undoped GaN layer helps to prevent or reduce the direct penetration of electrons into the substrate 1, thereby optimizing the electrical performance of the device.
[0032] Further, as a preferred embodiment of the utility model but not a limitation, a GaN buffer layer 2 is provided between the non-doped GaN layer 3 and the substrate 1, and the thickness of the GaN buffer layer 2 is 20-40 nm. The main function of the GaN buffer layer 2 is to bridge the lattice difference between the substrate 1 and the GaN layer, and to effectively reduce the dislocation caused by the lattice mismatch through progressive growth, thereby improving the crystal quality of the subsequent epitaxial layer. In addition, it also helps to improve the material adhesion and provide a flatter and more uniform growth platform for the top structure.
[0033] Further, as a preferred embodiment of the present invention but not a limitation, the total number of layers of the multi-quantum well layer 5 is at least 2, including a blue multi-quantum well layer 51 and a green multi-quantum well layer 52. By having at least one blue multi-quantum well layer 51 and one green multi-quantum well layer 52, the foundation of a wide color gamut LED is laid. Blue light is the main excitation source of LED light, while green light can widen the color gamut and improve color saturation. The combination of the two can initially achieve good coverage of the blue and green regions.
[0034] Optionally, in some embodiments, the total number of layers of the multi-quantum well layer 5 is 5-10 layers. By adjusting the total number of layers of the multi-quantum well layer, the light output intensity and spectral characteristics of the LED can be regulated. The range of 5 to 10 layers can ensure sufficient quantum wells to improve the luminous efficiency while avoiding the increase in complexity and possible decrease in efficiency caused by excessive stacking.
[0035] Further, as a preferred embodiment of the present invention but not a limitation, the thickness of the N-type GaN layer 4 is about 0.5-5 μm. This thickness range can ensure that there is enough volume for electron movement, thereby supporting efficient current conduction under high current density, while ensuring good mechanical strength and thermal stability. The doping concentration of Si is greater than 1018 / cm 3 The high doping concentration is beneficial to improve the conductivity of the N-type semiconductor, reduce resistance, and make electron injection smoother. The thickness of the P-type GaN layer 6 is about 50-250nm. This moderate thickness can ensure effective hole injection and reduce the increase in internal resistance caused by too thick, which is helpful to improve the electro-optical conversion efficiency of the device. The doping concentration of Mg is greater than 1018 / cm 3 , high concentration of Mg doping can significantly increase the conductivity of P-type GaN and promote the effective injection of holes.
[0036] like Figure 1 to Figure 2 As shown, the implementation method of Example 1 is as follows:
[0037] A structure of an LED chip capable of emitting blue-green light comprises a substrate 1, wherein the substrate 1 serves as a basic platform and a physical support platform for growing LED chip devices. The substrate 1 is made of silicon, which is the most commonly used material in the semiconductor industry, has a large output and a low cost. The thermal conductivity of silicon is better than that of sapphire, which helps to improve the heat dissipation performance of the LED. A multi-quantum well layer 5 is arranged on the top surface of the substrate 1, wherein the multi-quantum well layer 5 comprises a plurality of blue light multi-quantum well layers 51 and a plurality of green light multi-quantum well layers 52. A P-type GaN layer 6 is arranged above the multi-quantum well layer 5, and an N-type GaN layer 4 is arranged below the multi-quantum well layer 5. The N-type GaN layer 4 serves to provide electrons, and the P-type GaN layer 6 serves to provide holes. The P-type GaN layer 6 and the N-type GaN layer 4 together form a PN junction. The substrate 1 serves as the foundation and supporting platform of the LED chip, and provides a stable base for the LED chip to epitaxially grow other semiconductor layers. The N-type GaN layer 4 and the P-type GaN 6 layer together constitute the PN junction in the LED. The N-type GaN 4 layer introduces excess electrons by doping with silicon Si element, becoming the source of electrons. The P-type GaN layer introduces a state of lacking electrons, i.e., holes, by doping with magnesium Mg, becoming a positive charge carrier. When the LED chip is powered on, electrons and holes are injected from the P-type layer and the N-type layer into the multi-quantum well region respectively under the action of the electric field. When electrons and holes recombine in the multi-quantum well layer 5, electrons jump from the conduction band to the valence band to fill the holes, and at the same time, excess energy is released in the form of photons. Since the band gap width of the InGaN material varies with the indium (In) content, the different In contents of the blue multi-quantum well layer 51 and the green multi-quantum well layer 52 can make the quantum well layer emit light of a specific wavelength. The blue light quantum well layer contains a lower proportion of In and emits blue light with a wavelength in the range of 440-470nm; while the green light quantum well layer contains a higher proportion of In and emits light with a wavelength in the range of 515-550nm, i.e. green light. Through this process, blue light and green light are simultaneously generated and emitted from the LED chip. These lights can be used directly or converted into other colors such as white light through phosphors, suitable for various lighting and display applications. Unlike relying solely on blue light LEDs, blue-green light LED chips can output a spectrum containing more green light components. This spectral structure can more effectively excite the components in the phosphors that contribute more to green and red, thereby significantly expanding the color gamut of the LED.
[0038] The thickness of the N-type GaN layer 4 is about 0.5-5 μm. This thickness range can ensure that there is enough volume for electrons to move, thereby supporting efficient current conduction under high current density, while ensuring good mechanical strength and thermal stability. The doping concentration of Si is greater than 1018 / cm 3The high doping concentration is beneficial to improve the conductivity of the N-type semiconductor, reduce resistance, and make electron injection smoother. The thickness of the P-type GaN layer 6 is about 50-250nm. This moderate thickness can ensure effective hole injection and reduce the increase in internal resistance caused by too thick, which is helpful to improve the electro-optical conversion efficiency of the device. The doping concentration of Mg is greater than 1018 / cm 3 , high concentration of Mg doping can significantly increase the conductivity of P-type GaN and promote the effective injection of holes.
[0039] The blue light multi-quantum well layer 51 and the green light multi-quantum well layer 52 are both composed of an InGaN barrier layer and an InGaN well layer. The thickness of the InGaN barrier layer of the green light multi-quantum well layer 52 is 5-25nm, the In content is 20%-85%, and the emission wavelength is 515-550nm, covering the green light region, thereby enhancing the green expression of the LED chip and broadening the overall color gamut. The thickness of the InGaN well layer of the green light multi-quantum well layer is 1-7nm, and the In content is 1%-25%, in order to optimize the emission efficiency of green light, while ensuring a good electronic structure match with the barrier layer and promoting effective transitions between energy levels. The thickness of the InGaN barrier layer of the blue light multi-quantum well layer 51 is 5-25nm, the In content is 10%-40%, and the emission wavelength is 440-470nm. Blue light is the basic light source of LED and provides efficient energy for subsequent phosphor excitation. The thickness of the InGaN well layer of the blue light multi-quantum well layer 51 is 1-7nm, and the In content is 1%-25%, which corresponds to the well layer design in the green light multi-quantum well layer 52 to optimize the emission efficiency of blue light and the overall performance of the device.
[0040] A plurality of the blue multi-quantum well layers 51 and a plurality of the green multi-quantum well layers 52 are stacked alternately. By alternately arranging the blue and green multi-quantum well layers in the structure, not only can efficient emission of each band be obtained, but also the fine tuning and expansion of the spectrum can be achieved through the superposition effect of the two. Alternating stacking of multi-quantum well layers of different wavelengths helps to improve the absorption and conversion efficiency of light. The blue light layer is responsible for the basic high-intensity excitation, and the green light layer supplements and adjusts the color temperature. The synergistic effect of the two not only ensures high brightness output, but also makes the color distribution more uniform and natural, reducing color deviation.
[0041] An undoped GaN layer 3 is disposed below the N-type GaN layer 4, and the thickness of the undoped GaN layer 3 is 0.5-3 μm. As a lattice matching layer, the undoped GaN layer 3 can effectively alleviate the mismatch stress caused by the difference in lattice constants between different materials, such as sapphire or silicon substrates and GaN, reduce dislocation density, and thus improve the overall crystal quality and reliability of the device. As a barrier layer between the N-type GaN layer 4 and the substrate 1, the undoped GaN layer helps to prevent or reduce the direct penetration of electrons into the substrate 1, thereby optimizing the electrical performance of the device.
[0042] A GaN buffer layer 2 is provided between the non-doped GaN layer 3 and the substrate 1, and the thickness of the GaN buffer layer 2 is 20-40 nm. The main function of the GaN buffer layer 2 is to bridge the lattice difference between the substrate 1 and the GaN layer, and to effectively reduce the dislocation caused by the lattice mismatch through progressive growth, thereby improving the crystal quality of the subsequent epitaxial layer. In addition, it also helps to improve the material adhesion and provide a flatter and more uniform growth platform for the top structure.
[0043] The total number of layers of the multi-quantum well layer 5 is 5-10 layers. By adjusting the total number of layers of the multi-quantum well layer, the light output intensity and spectral characteristics of the LED can be regulated. The range of 5 to 10 layers can ensure sufficient quantum wells to improve the luminous efficiency, while avoiding the increase in complexity and possible decrease in efficiency caused by excessive stacking.
[0044] The implementation method of the second embodiment is as follows:
[0045] The difference between the second embodiment and the first embodiment is that a plurality of the blue multi-quantum well layers 51 and a plurality of the green multi-quantum well layers 52 are stacked in groups, that is, all the blue multi-quantum well layers 51 are stacked first and then all the green multi-quantum well layers 52 are stacked, or all the green multi-quantum well layers 52 are stacked first and then all the blue multi-quantum well layers 51 are stacked. Group stacking simplifies the manufacturing process steps, avoids the complex and precise control required in the alternating deposition process of quantum well layers of different wavelengths, reduces the manufacturing difficulty and cost, and improves production efficiency. Since the interface properties between similar quantum well layers are similar, group stacking is conducive to reducing interface defects and improving the internal consistency of the device, thereby improving the overall photoelectric conversion efficiency and reliability.
[0046] The implementation method of the third embodiment is as follows:
[0047] The difference between the third embodiment and the first embodiment is that the total number of layers of the multi-quantum well layer 5 is 2, including a blue multi-quantum well layer 51 and a green multi-quantum well layer 52. The foundation of wide color gamut LED is laid by having a blue multi-quantum well layer 51 and a green multi-quantum well layer 52. Blue light is the main excitation source of LED light, while green light can widen the color gamut and improve color saturation. The combination of the two can initially achieve good coverage of the blue and green regions.
[0048] Specifically, a method for producing a structure of an LED chip capable of emitting blue-green light is as follows:
[0049] The epitaxial growth is done using MOCVD (Metal Organic Chemical Vapor Deposition).
[0050] Step 1: Pre-treat the substrate, heat it to 1000-1200℃ and bake it to remove moisture and impurities on the surface of the substrate and improve the adhesion of the subsequent epitaxial layer. The time is controlled within 5-20 minutes to achieve the best cleaning effect;
[0051] Step 2: The temperature is lowered to 400-600°C to grow a 20-40nm GaN buffer layer, providing a smooth, low-defect starting surface for the subsequent epitaxial layer, reducing lattice mismatch and thus optimizing the overall crystal quality.
[0052] Step 3: The temperature is raised to 1000-1200°C again to grow an undoped GaN layer with a thickness of 0.5-3 μm, which serves as the basis for subsequent doped layers to further enhance structural stability and electrical properties;
[0053] Step 4: At the same high temperature, grow an N-type doped GaN layer with a thickness of about 0.5-5 microns and a silicon (Si) doping concentration greater than 1×10^18 / cm³ to ensure high conductivity and efficient electron injection;
[0054] Step 5: The temperature is reduced to 650-950°C, and a multi-quantum well layer is grown, containing at least one blue light layer and one green light multi-quantum well layer. By controlling the In content and thickness, the blue-green light emission is optimized and the color gamut is widened;
[0055] Step 6: Grow a P-type GaN layer at 900-1100°C with a thickness of about 50-250 nanometers and a magnesium (Mg) doping concentration of >1×10^18 / cm³ to ensure effective hole injection;
[0056] Step 7: The temperature is lowered to below 800°C for annealing to release stress, stabilize the crystal structure, and enhance device performance and reliability;
[0057] Step 8: Complete electrical connections, cut into single chips, and prepare for packaging and final testing.
[0058] In summary, the utility model solves the problem of small color gamut coverage of traditional blue light LED chips.
[0059] It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the "first" information may also be referred to as the "second" information, and similarly, the "second" information may also be referred to as the "first" information. In addition, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0060] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the protection scope of the present invention.
Claims
1. A structure of an LED chip capable of emitting blue-green light, characterized in that: The invention comprises a substrate (1), wherein the function of the substrate (1) is to serve as a basic platform and a physical support platform for the growth of LED chip devices, wherein a multi-quantum well layer (5) is arranged on the top surface of the substrate (1), wherein the multi-quantum well layer (5) comprises a plurality of blue light multi-quantum well layers (51) and a plurality of green light multi-quantum well layers (52), wherein a P-type GaN layer (6) is arranged above the multi-quantum well layer (5), and an N-type GaN layer (4) is arranged below the multi-quantum well layer (5), wherein the function of the N-type GaN layer (4) is to provide electrons, and the function of the P-type GaN layer (6) is to provide holes, and the P-type GaN layer (6) and the N-type GaN layer (4) together form a PN junction; The total number of layers of the multi-quantum well layer (5) is at least 2, including a blue light multi-quantum well layer (51) and a green light multi-quantum well layer (52).
2. The structure of a LED chip capable of emitting blue-green light according to claim 1, characterized in that: The blue light multi-quantum well layer (51) and the green light multi-quantum well layer (52) are both composed of an InGaN barrier layer and an InGaN well layer.
3. The structure of a LED chip capable of emitting blue-green light according to claim 2, characterized in that: The thickness of the InGaN barrier layer of the green light multi-quantum well layer (52) is 5-25 nm, the emission wavelength is 515-550 nm, and the thickness of the InGaN well layer of the green light multi-quantum well layer (52) is 1-7 nm.
4. The structure of a LED chip capable of emitting blue-green light according to claim 2, characterized in that: The thickness of the InGaN barrier layer of the blue light multi-quantum well layer (51) is 5-25 nm, the emission wavelength is 440-470 nm, and the thickness of the InGaN well layer of the blue light multi-quantum well layer (51) is 1-7 nm.
5. The structure of the LED chip capable of emitting blue-green light according to claim 1, characterized in that: A plurality of the blue light multi-quantum well layers (51) and a plurality of the green light multi-quantum well layers (52) are alternately stacked.
6. The structure of a LED chip capable of emitting blue-green light according to claim 1, characterized in that: A non-doped GaN layer (3) is provided below the N-type GaN layer (4); the thickness of the non-doped GaN layer (3) is 0.5-3 μm.
7. The structure of the LED chip capable of emitting blue-green light according to claim 6, characterized in that: A GaN buffer layer (2) is provided between the non-doped GaN layer (3) and the substrate (1), and the thickness of the GaN buffer layer (2) is 20-40 nm.
8. The structure of a LED chip capable of emitting blue-green light according to claim 1, characterized in that: The material of the substrate (1) is one of sapphire, silicon or gallium nitride.
9. The structure of a LED chip capable of emitting blue-green light according to claim 1, characterized in that: The thickness of the N-type GaN layer (4) is 0.5-5 μm, and the thickness of the P-type GaN layer (6) is 50-250 nm.