Wavelength conversion apparatus and preparation method therefor, and light-emitting apparatus

Abstract

A wavelength conversion apparatus (10) and a preparation method therefor, and a light-emitting apparatus (1). The wavelength conversion apparatus (10) comprises a substrate (100), a first oxide transition layer (150), a reflective layer (200) and a wavelength conversion layer (300), wherein the first oxide transition layer (150) is disposed on a surface of the substrate (100); the reflective layer (200) is disposed on the surface of the first oxide transition layer (150) away from the substrate (100); and the wavelength conversion layer (300) is disposed on the surface of the reflective layer (200) away from the first oxide transition layer (150). The percentage difference between the lattice parameters of any two adjacent layers does not exceed 50%; and / or, the percentage difference between the linear thermal expansion coefficients of any two adjacent layers does not exceed 100%. The wavelength conversion apparatus (10) does not require the provision of a separate adhesive layer. The first oxide transition layer (150), the reflective layer (200), the substrate (100) and the wavelength conversion layer (300) are bonded by means of chemical bonds, forming stable thermal conduction film layer interfaces, thereby achieving high thermal stability and high reliability.

Description

Wavelength conversion device and preparation method thereof, and light-emitting device Technical Field

[0001] The present application relates to the field of light source technology, and in particular to a wavelength conversion device and a preparation method thereof, and a light-emitting device. Background Art

[0002] Currently, laser-fluorescence conversion light sources are widely used in LED lighting, stage lights, car lights, searchlights, and other equipment, offering advantages such as high brightness and high-temperature stability. The wavelength conversion device is the core component of the laser-fluorescence conversion light source, and its performance plays a decisive role in the quality of the laser-fluorescence conversion light source.

[0003] Currently, a common packaging method for wavelength conversion devices is to prepare a phosphor layer (single-phase ceramic or multi-phase ceramic), polish one surface of the phosphor layer, and then form a metal reflective layer on the polished surface of the phosphor layer through a physical sputtering or evaporation process. The side of the reflective layer is then placed on a metal heat dissipation substrate coated with a low-temperature curing silver paste. The entire device is placed in a sintering furnace for low-temperature curing and bonding, or soldering is performed to achieve a connection between the substrate layer and the phosphor layer. Metal heat dissipation substrates have excellent thermal conductivity. Therefore, the bonding layer, as a connecting layer, has a significant impact on the excellent heat dissipation performance of the phosphor layer to the metal substrate layer. The bonding layer is typically a solder layer or a sintered silver layer. The solder layer may produce defects such as pores and cracks during the soldering process, affecting the connection quality. The tolerance of the soldered material also limits the choice of solder type. When used as a bonding layer, sintered silver offers advantages over conventional solder in terms of both high thermal and electrical conductivity. It also features low-temperature sintering, eliminating the need for high pressure and high temperature. However, the sintering process is lengthy, resulting in low production efficiency. Furthermore, the resulting bonding layer is porous, making it difficult to detect internal voids. Numerous and large voids can negatively impact heat dissipation and interlayer adhesion. Consequently, this type of fixed structure can experience issues such as fall-off, reduced efficiency, failure, and decreased reliability in practical applications. Summary of the Invention

[0004] The purpose of this application is to provide a wavelength conversion device and a preparation method thereof, and a light-emitting device to improve the above-mentioned problems.

[0005] In a first aspect, embodiments of the present application provide a wavelength conversion device, comprising a substrate, a first oxide transition layer, a reflective layer, and a wavelength conversion layer, wherein the first oxide transition layer is disposed on a surface of the substrate, the reflective layer is disposed on a surface of the first oxide transition layer away from the substrate, and the wavelength conversion layer is disposed on a surface of the reflective layer away from the reflective layer;

[0006] The difference in lattice parameters between any adjacent layers does not exceed 50%;

[0007] And / or, the percentage difference in linear thermal expansion coefficient between any adjacent layers does not exceed 100%.

[0008] In one embodiment, the percentage difference in lattice parameters between any adjacent layers does not exceed 30%.

[0009] In one embodiment, the percentage difference in linear thermal expansion coefficient between any adjacent layers does not exceed 60%.

[0010] In one embodiment, the first oxide transition layer is selected from at least one of aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, nickel oxide, and neodymium oxide.

[0011] In one embodiment, the wavelength conversion device further includes a second oxide transition layer, and the second oxide transition layer is disposed between the reflective layer and the wavelength conversion layer.

[0012] In one embodiment, the second oxide transition layer is selected from at least one of aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, nickel oxide, and neodymium oxide.

[0013] In one embodiment, the second oxide transition layer is selected from aluminum oxide.

[0014] In one embodiment, the reflective layer is a dielectric reflective layer, comprising a first dielectric film and a second dielectric film periodically and alternately stacked, wherein the first dielectric film and the second dielectric film each have at least one layer, and the refractive index of the first dielectric film is greater than the refractive index of the second dielectric film.

[0015] In one embodiment, the first dielectric film is selected from at least one of titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, and neodymium oxide, and the second dielectric film is selected from at least one of aluminum oxide and silicon oxide.

[0016] In one embodiment, the first oxide transition layer, the reflective layer, and the wavelength conversion layer are formed by vapor deposition.

[0017] In a second aspect, embodiments of the present application further provide a method for preparing a wavelength conversion device, comprising:

[0018] A substrate is provided, and a first oxide transition layer is sequentially deposited on a surface of one side of the substrate by vapor deposition; a reflective layer is formed on a surface of the first oxide transition layer away from the substrate, and a wavelength conversion layer is formed on a surface of the reflective layer away from the first oxide transition layer.

[0019] In one embodiment, before forming the wavelength conversion layer, a second oxide transition layer is formed on the surface of the reflective layer away from the first oxide transition layer by vapor deposition, and then a wavelength conversion layer is formed on the surface of the second oxide transition layer away from the reflective layer.

[0020] In a third aspect, an embodiment of the present application further provides a light-emitting device, which includes a laser light source and the above-mentioned wavelength conversion device, wherein the laser light source emits excitation light to excite the wavelength conversion device to emit stimulated light.

[0021] The wavelength conversion device and light-emitting device provided in the present application do not require a separate adhesive layer. The first metal transition layer, the reflective layer, the substrate and the wavelength conversion layer are bonded by chemical bonds, wherein the difference percentage of the lattice parameters between any adjacent layers does not exceed 50%; and / or, the difference percentage of the linear thermal expansion coefficient between any adjacent layers does not exceed 100%, thereby forming a stable heat-conducting film layer interface, achieving high thermal stability and high reliability, strong interlayer adhesion, thin thickness, low thermal resistance, and significantly improving the thermal conductivity of the wavelength conversion device.

[0022] The preparation method of the wavelength conversion device provided in the present application starts from a substrate and uses vapor deposition to epitaxially grow a first oxide transition layer, a reflective layer and a wavelength conversion layer. The first oxide transition layer, the reflective layer, the substrate and the wavelength conversion layer are chemically bonded, and no traditional adhesive is required to form a stable heat-conducting film layer interface. The prepared wavelength conversion device can achieve high thermal stability and high reliability, strong interlayer adhesion, thin thickness and low thermal resistance, which can significantly improve the reliability and service life of the wavelength conversion device.

[0023] These and other aspects of the present application will become more readily apparent from the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0025] FIG1 is a schematic structural diagram of a wavelength conversion device in the prior art shown in this application.

[0026] FIG2 is a schematic structural diagram of a wavelength conversion device provided in Example 1 of the present application.

[0027] FIG3 is a schematic structural diagram of a wavelength conversion device provided in Example 2 of the present application.

[0028] FIG4 is a schematic structural diagram of a light-emitting device provided in Example 3 of the present application. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0030] Currently, wavelength conversion devices typically consist of a stacked substrate, adhesive layer, reflective layer, and light-emitting layer. This method of fabrication can lead to unstable interlayer adhesion and linear thermal expansion coefficient matching, resulting in poor interlayer adhesion and the light-emitting layer easily falling off the heatsink substrate. Furthermore, the complex interlayer structure makes linear thermal expansion coefficient matching more challenging. During use, as the ambient temperature fluctuates, the interlayer materials can contract and expand to varying degrees, ultimately leading to device failure and negatively impacting the device's reliability and long-term stability.

[0031] Figure 1 shows a conventional wavelength conversion device, which includes, from top to bottom, a phosphor layer 1, a metal reflective layer 2, a protective layer 3, an adhesive layer 4, and a heat dissipation substrate layer 5. The adhesive layer 4 serves to bond the phosphor layer 1 and the heat dissipation substrate layer 5, typically using solder or silver glue. This method of fabricating wavelength conversion devices requires a wide variety of film layers, resulting in a complex preparation process and high equipment requirements.

[0032] Example 1

[0033] 2 , this embodiment provides a wavelength conversion device 10, comprising a substrate 100, a first oxide transition layer 150, a reflective layer 200, and a wavelength conversion layer 300, wherein the first oxide transition layer 150 is disposed on a side surface of the substrate 100, the reflective layer 200 is disposed on a surface of the first oxide transition layer away from the substrate 100, and the wavelength conversion layer 300 is disposed on a surface of the reflective layer 200 away from the first oxide transition layer 150; wherein the percentage difference in lattice parameters between any adjacent layers does not exceed 50%; and / or the percentage difference in linear thermal expansion coefficient between any adjacent layers does not exceed 100%.

[0034] Specifically, in some embodiments of the present application, the lattice parameter difference between any adjacent layers does not exceed 50%. When the lattice parameter difference between each layer and its adjacent layers in the substrate 100, first oxide transition layer 150, reflective layer 200, and wavelength conversion layer 300 does not exceed 50%, higher lattice matching helps reduce stress and defects, and improves material stability and performance. Alternatively, when the linear thermal expansion coefficient difference between each layer and its adjacent layers in the substrate 100, first oxide transition layer 150, reflective layer 200, and wavelength conversion layer 300 does not exceed 100%, particularly when the wavelength conversion device accumulates a large amount of heat during use, causing linear thermal expansion, and then shrinks back to its original volume after use due to heat dissipation, selecting a linear thermal expansion coefficient difference between each adjacent layer to not exceed 100% allows the linear thermal expansion and contraction of each adjacent layer to be closer, significantly improving the reliability and service life of the wavelength conversion device. In some embodiments of the present application, in order to help reduce stress and defects and improve the stability and performance of the material, while significantly improving the reliability and service life of the wavelength conversion device, the percentage difference in lattice parameters between any adjacent layers does not exceed 50%; and the percentage difference in linear thermal expansion coefficient between any adjacent layers does not exceed 100%, that is, each adjacent layer is selected to meet the above two conditions at the same time.

[0035] In some embodiments of the present application, to achieve higher lattice matching, which helps reduce stress and defects and improve material stability and performance, the difference in lattice parameters between each layer and adjacent layers in the substrate 100, first oxide transition layer 150, reflective layer 200, and wavelength conversion layer 300 does not exceed 30%. For example, the difference in lattice parameters between each layer and adjacent layers is 10%, 20%, or 30%.

[0036] In some embodiments of the present application, to significantly improve the reliability and service life of the wavelength conversion device, the difference in linear thermal expansion coefficient between each layer and adjacent layers in the substrate 100, the first oxide transition layer 150, the reflective layer 200, and the wavelength conversion layer 300 does not exceed 60%. For example, the difference in linear thermal expansion coefficient between each layer and adjacent layers is 10%, 20%, 30%, 40%, 50%, or 60%.

[0037] It should be noted that in some embodiments of the present application, the percentage difference in lattice parameters between each layer and the adjacent layer in the substrate 100, the first oxide transition layer 150, the reflective layer 200 and the wavelength conversion layer 300 does not exceed 30%, or the percentage difference in linear thermal expansion coefficient between each layer and the adjacent layer in the substrate 100, the first oxide transition layer 150, the reflective layer 200 and the wavelength conversion layer 300 does not exceed 60%; in one embodiment of the present application, the percentage difference in lattice parameters between each layer and the adjacent layer in the substrate 100, the first oxide transition layer 150, the reflective layer 200 and the wavelength conversion layer 300 does not exceed 30%, and the percentage difference in linear thermal expansion coefficient between each layer and the adjacent layer in the substrate 100, the first oxide transition layer 150, the reflective layer 200 and the wavelength conversion layer 300 does not exceed 60%.

[0038] In this embodiment, the substrate 100 may be a ceramic substrate, which can form a tighter and more stable chemical bond with the first oxide transition layer 150, thereby improving the bonding strength between the substrate 100 and the first oxide transition layer 150. In other embodiments, the substrate 100 may also be a sapphire substrate, etc., which is not limited in this embodiment.

[0039] The first oxide transition layer 150 is disposed between the substrate and the reflective layer. The provision of the oxide transition layer 250 enhances the chemical bonding between the substrate 100 and the first oxide transition layer 150. Similarly, the chemical bonding between the reflective layer 200 and the first oxide transition layer 150 also enhances the bonding strength, thereby improving the bonding strength between the wavelength conversion layer 300 and the reflective layer 200. Furthermore, the provision of the oxide transition layer 250 relaxes the internal stress formed between the reflective layer 200 and the substrate 100 due to the different crystal structures, thereby reducing the risk of cracking and other defects in the subsequent interlayer structure.

[0040] The first oxide transition layer 150 may be selected from at least one of aluminum oxide and silicon oxide, with aluminum oxide being preferred. In other embodiments, the first oxide transition layer 150 may also be selected from one or more of titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, nickel oxide, and neodymium oxide.

[0041] The thickness of the first oxide transition layer 150 may be, for example, 15 nm to 25 nm. Of course, in some other embodiments, the thickness of the first oxide transition layer 150 may also be other values, which is not limited in this embodiment.

[0042] The reflective layer 200 can reflect the converted light from the wavelength conversion layer 300 and can also reflect the excitation light. It also serves to tightly connect the first oxide transition layer 150 and the wavelength conversion layer 300. Furthermore, the reflective layer 200 can quickly transfer some of the heat generated when the excitation light strikes the wavelength conversion layer 300 to the substrate 100 for further dissipation.

[0043] In this embodiment, reflective layer 200 is a dielectric reflective layer. Dielectric reflective layers have high reflectivity and can be customized based on the required reflective spectral range and reflectivity to accommodate different wavelength conversion requirements. Specifically, referring to FIG3 , reflective layer 200 is a dielectric reflective layer. Using a dielectric reflective layer as reflective layer 200 can increase the refractive index of reflective layer 200 and expand the wavelength range of the wavelength conversion device.

[0044] The dielectric reflective layer includes a first dielectric film and a second dielectric film that are periodically and alternately stacked. The first dielectric film and the second dielectric film each comprise at least one layer. The refractive index of the first dielectric film is greater than the refractive index of the second dielectric film, meaning that the reflectivities of the two adjacent dielectric films are unequal. In a preferred embodiment, the number of first dielectric films can be one greater than the number of second dielectric films. In this arrangement, the outermost portion of the dielectric reflective layer can be the first dielectric film, significantly increasing the reflectivity of the reflective layer 200.

[0045] Both the first dielectric film and the second dielectric film can be made of fluorides, oxides, sulfides, and the like, such as tantalum oxide and silicon dioxide, and this embodiment is not limited thereto. In a more specific embodiment, the first dielectric film can be selected from at least one of titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, and neodymium oxide, and the second dielectric film can be selected from at least one of aluminum oxide and silicon oxide.

[0046] For example, referring to FIG. 3 , FIG. 3 shows the structure of a reflective layer 200 . The reflective layer 200 includes two first dielectric films and one second dielectric film. The first dielectric film may be a tantalum oxide layer 210, and the second dielectric film may be a silicon dioxide layer 220. The tantalum oxide layers 210 and silicon dioxide layers 220 are stacked, with adjacent tantalum oxide layers 210 and silicon dioxide layers 220 arranged periodically. Specifically, the silicon dioxide layer 220 is disposed between the two tantalum oxide layers 210. The tantalum oxide layer 210 of the reflective layer 200 is bonded to the first oxide transition layer 150, while the other tantalum oxide layer 210 is bonded to the wavelength conversion layer 300. Because the refractive index of the tantalum oxide layer 210 is greater than that of the silicon dioxide layer 220, and the two tantalum oxide layers 210 are located outside the reflective layer 200, the refractive index of the entire reflective layer 200 is higher, significantly increasing the reflectivity of the reflective layer 200.

[0047] The wavelength conversion layer 300 may be a fluorescent ceramic layer. The fluorescent ceramic layer may be a Ce:YAG or Ce:LuAG single-phase ceramic, or an Al2O3-Ce:YAG or Al2O3-Ce:LuAG multiphase ceramic, which is not specifically limited in this embodiment. The wavelength conversion layer 300 can convert the excitation light into stimulated light under the excitation of the excitation light. In a more specific embodiment, the laser light may be blue light, and the wavelength conversion layer 300 can convert the blue light into yellow fluorescence.

[0048] By providing the first oxide transition layer 150 , the internal stresses formed in different functional film layers due to different crystal structures can be gradually relaxed, thereby reducing defects such as cracking in subsequent interlayer structures.

[0049] Lattice Parameters Linear Thermal Expansion Linear Thermal Expansion In this embodiment, the first oxide transition layer 150, the reflective layer 200, and the wavelength conversion layer 300 are all formed sequentially by vapor deposition. This embodiment has the advantage that during the vapor deposition process, chemical bonds form between adjacent layers, enhancing their adhesion and forming a stable thermally conductive film interface, achieving high thermal stability and reliability. The strong interlayer adhesion, thin thickness, and low thermal resistance significantly enhance the thermal conductivity of the wavelength conversion device 10. During the fabrication process, no additional adhesive is required, reducing the thickness of the entire wavelength conversion device 10 and avoiding the void problem caused by the use of adhesives. This also reduces the number of fabrication steps and improves production efficiency.

[0050] Among them, the vapor deposition method can be a vacuum evaporation method, that is, heating in a vacuum to evaporate the metal, alloy or compound, and then condensing it on the surface of the substrate, such as a pulsed laser deposition method, wherein pulsed laser deposition refers to the use of a high-energy laser beam as a heat source to bombard the material to be evaporated, and then evaporate the thin film on the substrate. The vapor deposition method can also be a magnetron sputtering method, that is, using high-speed positive ions to bombard a target material (cathode) so that the atoms on the surface of the target material escape with a certain energy and then deposit on the surface of the workpiece. The vapor deposition method can also be ion plating, that is, using a glow discharge of an inert gas to evaporate and ionize the metal or alloy to be plated, and these charged ions bombard the surface of the substrate (workpiece) and simultaneously deposit on it to form a coating. Vapor deposition can also be an atomic layer deposition method, that is, by alternately passing a gaseous precursor into a reaction chamber and causing a gas-curing reaction on the surface of the substrate to form a thin film.

[0051] Specifically, the wavelength conversion device 10 can be prepared as follows:

[0052] A substrate 100 is provided. The substrate 100 is an aluminum nitride ceramic substrate. The substrate 100 is ultrasonically cleaned with acetone, isopropyl alcohol, and deionized water in sequence, and blown dry with a nitrogen gas flow. The surface of the copper substrate 100 is then plasma cleaned in an air or oxygen atmosphere for 10 minutes. After cleaning, a baffle is set on the surface of the substrate 100. The middle of the baffle forms a deposition area. The baffle is mainly used to protect the non-deposition area of ​​the substrate 100. A first oxide transition layer 150 is formed in the deposition area of ​​the substrate 100 using atomic layer deposition. The first oxide transition layer 150 is composed of aluminum oxide. The thickness of the first oxide transition layer 150 is 20 nm. When performing atomic layer deposition, the aluminum source used is trimethylaluminum and the oxygen source is pure water.

[0053] After the first oxide transition layer 150 is formed, the substrate 100 is placed in an annealing furnace for annealing for at least 1 hour. During the annealing, the substrate 100 is maintained in an atmosphere of oxygen:argon=1:1. The annealing temperature may be 300°C.

[0054] Continuing with pulsed laser deposition, a reflective layer 200 is formed on the surface of the first oxide transition layer 150 away from the substrate 100. The thickness of the reflective layer 200 can be, for example, 80 nm to 120 nm. The reflective layer 200 comprises a sequentially deposited high-reflectivity tantalum oxide dielectric film and a low-reflectivity silicon dioxide dielectric film. After the reflective layer 200 is formed, it is annealed for 30 minutes. Then, a wavelength conversion layer 300 is formed on the surface of the reflective layer 200 away from the first oxide transition layer 150 using magnetron DC sputtering. The thickness of the wavelength conversion layer 300 can be 1500 to 5000 nm.

[0055] After the preparation is completed, the prepared wavelength conversion device 10 is annealed at a high temperature of 600-800° C. in a muffle furnace for 1-3 hours, so that the linear thermal expansion coefficients between the layers of the wavelength conversion device 10 are matched, the chemical properties are stable, and the structure is dense.

[0056] In some embodiments, referring again to FIG. 2 , the wavelength conversion device 10 may further include a second oxide transition layer 250 disposed between the wavelength conversion layer 300 and the reflective layer 200. The provision of the second oxide transition layer 250 enhances chemical bonding between the wavelength conversion layer 300 and the second oxide transition layer 250. Similarly, chemical bonding between the reflective layer 200 and the second oxide transition layer 250 may also enhance bonding, thereby improving the bonding strength between the wavelength conversion layer 300 and the reflective layer 200. Furthermore, the provision of the second oxide transition layer 250 may also relax internal stress caused by the different crystal structures between the reflective layer 200 and the wavelength conversion layer 300, thereby reducing the risk of cracking and other defects in the subsequent interlayer structure.

[0057] The second oxide transition layer 250 may be selected from at least one of aluminum oxide and silicon oxide. In other embodiments, the second oxide transition layer 250 may also be selected from one or more of titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, nickel oxide, neodymium oxide, and other oxides.

[0058] It should be noted that in some embodiments of the present application, when providing the second oxide transition layer 250, it is also necessary to consider that the difference in lattice parameters between the second oxide transition layer 250 and the adjacent layers does not exceed 50%, and / or the difference in linear thermal expansion coefficient between the second oxide transition layer 250 and the adjacent layers does not exceed 100%. For example, if the second oxide transition layer 250 is adjacent to the reflective layer 200 and the wavelength conversion layer 300, respectively, it is necessary to consider that the difference in lattice parameters between the second oxide transition layer 2500 and the reflective layer 200 and the wavelength conversion layer 300 does not exceed 50%, and / or the difference in linear thermal expansion coefficient between the second oxide transition layer 2500 and the reflective layer 200 and the wavelength conversion layer 300 does not exceed 100%. In this embodiment, the wavelength conversion layer 300 uses YAG:Ce, where YAG is a cubic crystal system composed of yttrium, aluminum, and oxygen, with a lattice parameter of When selecting the second oxide transition layer 250, a material having a lattice parameter that matches or is close to that of the wavelength conversion layer 300 and / or a linear thermal expansion coefficient that is similar to that of the wavelength conversion layer 300 should be selected. A higher lattice match helps reduce stress and defects, and improves material stability and performance.

[0059] See Table 1, which shows the lattice parameters of common oxides:

[0060] As can be seen from Table 1, alumina has a lattice parameter and linear thermal expansion coefficient close to YAG. Specifically, the lattice parameter of YAG is Lattice parameters in alumina That is, the lattice parameter of aluminum oxide and the lattice parameters of YAG The difference percentage of the lattice parameters between adjacent layers does not exceed 50%. Similarly, the linear thermal expansion coefficient of YAG is 6.9 (10 -6 K -1 ), and the linear thermal expansion coefficient of alumina is 8.41(10 -6 K -1) must meet the requirement that the difference in linear thermal expansion coefficient does not exceed 100%. Therefore, it is most commonly used as an oxide transition layer material for YAG films. Yttrium oxide (Y2O3) is also a good choice for the oxide transition layer in YAG films because it has a similar crystal structure and lattice parameters to YAG. Additionally, niobium oxide (Nb2O5) and hafnium oxide (HfO2) are also considered as oxide transition layer materials for YAG films.

[0061] It should be noted that in some embodiments of the present application, when selecting the first dielectric film and the second dielectric film that are periodically alternately stacked in the dielectric reflective layer, and when selecting the first oxide transition layer and the substrate, the difference in lattice parameters between any adjacent layers is also required to be no more than 50%; and / or the difference in linear thermal expansion coefficient between any adjacent layers is required to be no more than 100%. This is not further elaborated.

[0062] In addition, when considering that the dielectric reflective layer and other adjacent layers satisfy the requirement that the percentage difference in lattice parameters between any adjacent layers does not exceed 50%; and / or the percentage difference in linear thermal expansion coefficients between any adjacent layers does not exceed 100%, the lattice parameters and linear thermal expansion coefficients of the first dielectric film and the second dielectric film periodically alternately stacked in the dielectric reflective layer and other adjacent layers need to be considered.

[0063] It should be noted that in some embodiments of the present application, the percentage difference in lattice parameters between any adjacent layers does not exceed 50%, which means that only one of the lattice parameters (a, b, c) between any adjacent layers needs to be similar and meet the lattice parameter difference percentage of no more than 50%. For example, if the lattice parameters of the wavelength conversion layer are (a1, b1, c1), the lattice parameters of the adjacent second oxide transition layer 250 are (a2, b2, c2), and the lattice parameters of the reflective layer adjacent to the second oxide transition layer 250 are (a3, b3, c3), then the percentage difference between any one of (a1, b1, c1) and any one of (a2, b2, c2) does not exceed 50%, and the percentage difference between any one of (a2, b2, c2) and any one of (a3, b3, c3) does not exceed 50%. The calculation method for any other adjacent layers is the same and is not repeated here.

[0064] The thickness of the second oxide transition layer 250 may be, for example, 15 nm to 25 nm. Of course, in some other embodiments, the thickness of the second oxide transition layer 250 may also be other values, which is not limited in this embodiment.

[0065] At this time, the wavelength conversion device 10 can be prepared in the following manner:

[0066] A substrate 100 is provided, for example, an aluminum nitride ceramic substrate is selected, and the substrate 100 is ultrasonically cleaned in acetone, isopropyl alcohol, and deionized water in sequence, and blown dry with a nitrogen gas flow. Then, the surface of the copper substrate 100 is plasma cleaned in an air or oxygen atmosphere for 10 minutes. After cleaning, a baffle is set on the surface of the substrate 100, and the middle of the baffle forms a deposition area. The baffle is mainly used to protect the non-deposition area of ​​the substrate 100. A first oxide transition layer 150 is formed in the deposition area of ​​the substrate 100 using atomic layer deposition. The first oxide transition layer 150 is composed of aluminum oxide and has a thickness of 20 nm. When performing atomic layer deposition, the aluminum source used is trimethylaluminum and the oxygen source is pure water.

[0067] After the first oxide transition layer 150 is formed, the substrate 100 is placed in an annealing furnace for annealing for at least 1 hour. During the annealing, the substrate 100 is maintained in an atmosphere of oxygen:argon=1:1. The annealing temperature may be 300°C.

[0068] Continuing with pulsed laser deposition, a reflective layer 200 is formed on the surface of the first oxide transition layer 150 away from the substrate 100. The thickness of reflective layer 200 can be, for example, 80 nm to 120 nm. Reflective layer 200 comprises a sequentially deposited high-reflectivity tantalum oxide dielectric film and a low-reflectivity silicon dioxide dielectric film. After the reflective layer 200 is formed, it is annealed for 30 minutes. Atomic layer deposition is then used to grow a 20 nm thick second oxide transition layer 250, using the same growth method as the first oxide transition layer 150.

[0069] Then, a wavelength conversion layer 300 is formed on the surface of the reflective layer 200 away from the first oxide transition layer 150 by magnetron DC sputtering. The thickness of the wavelength conversion layer 300 may be 1500-5000 nm.

[0070] After preparation, the prepared wavelength conversion device is annealed at a high temperature of 600-800°C in a muffle furnace for 1-3 hours, so that the linear thermal expansion coefficients between the layers of the wavelength conversion device are matched, the chemical properties are stable, and the structure is dense, which can significantly improve the reliability and service life of the wavelength conversion device.

[0071] Example 2

[0072] This embodiment provides a wavelength conversion device 10 , which differs from the first embodiment in that the wavelength conversion device 10 is prepared differently in this embodiment. For the same parts, please refer to the contents of the first embodiment, which will not be described in detail in this embodiment.

[0073] In this embodiment, the wavelength conversion device 10 can be prepared in the following manner:

[0074] A substrate 100 is provided, and the substrate 100 is ultrasonically cleaned in sequence using acetone, isopropyl alcohol, and deionized water, and blown dry using a nitrogen gas flow. The surface of the copper substrate 100 is then plasma cleaned in an air or oxygen atmosphere for 10 minutes. After the cleaning is completed, a baffle is set on the surface of the substrate 100, and the middle of the baffle forms a deposition area. A first oxide transition layer 150 is formed in the deposition area of ​​the substrate 100 using magnetron sputtering. The first oxide transition layer 150 is an aluminum oxide layer. After the first oxide transition layer 150 is formed, a reflective layer 200 is formed on the surface of the first oxide transition layer 150 away from the substrate 100 using magnetron sputtering. The thickness of the reflective layer 200 can be 80nm-120nm, and the reflective layer includes a periodically arranged tantalum oxide high-reflectivity dielectric film and a silicon dioxide low-reflectivity dielectric film.

[0075] After the reflective layer 200 is formed, the second oxide transition layer 250 is formed on the surface of the reflective layer 200 away from the first oxide transition layer 150 by continuing to use magnetron sputtering. The thickness of the second oxide transition layer 250 can be 5nm-20nm; the wavelength conversion layer 300 is formed on the surface of the reflective layer 200 away from the first oxide transition layer 150 by continuing to use magnetron sputtering. The thickness of the wavelength conversion layer 300 can be 1500-5000nm.

[0076] The wavelength conversion device 10 provided in this embodiment does not require a separate adhesive layer. The first oxide transition layer 150, the reflective layer 200, the substrate 100, and the wavelength conversion layer 300 are chemically bonded to form a stable heat-conducting film interface, thereby achieving high thermal stability and high reliability. The interlayer adhesion is strong, the thickness is thin, and the thermal resistance is low, which can significantly improve the thermal conductivity of the wavelength conversion device 10.

[0077] The preparation method of the wavelength conversion device 10 provided in the present application starts from a substrate 100 and uses vapor deposition to epitaxially grow a first oxide transition layer 150, a reflective layer 200 and a wavelength conversion layer 300. The first oxide transition layer 150, the reflective layer 200, the substrate 100 and the wavelength conversion layer 300 are chemically bonded to each other without the use of traditional adhesives, forming a stable heat-conducting film layer interface. The prepared wavelength conversion device 10 can achieve high thermal stability and high reliability, strong interlayer adhesion, thin thickness and low thermal resistance, which can significantly improve the reliability and service life of the wavelength conversion device.

[0078] Example 3

[0079] Referring to Figure 4, this embodiment provides a light-emitting device 1, which includes a laser light source 20 and a wavelength conversion device 10. The laser light source 20 emits excitation light to excite the wavelength conversion device 10 to emit stimulated light, wherein the wavelength conversion device 10 can be any one of the aforementioned embodiments. For details, please refer to the relevant content of the aforementioned embodiments.

[0080] The laser light source 20 may be, for example, a blue light source. In some other implementations, the laser light source 20 may also be a light source of other colors, which is not limited in this embodiment.

[0081] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A wavelength conversion device, characterized in that: include: substrate; A first oxide transition layer, wherein the first oxide transition layer is disposed on a surface of the substrate; A reflective layer, the reflective layer being disposed on a surface of the first oxide transition layer away from the substrate; as well as a wavelength conversion layer, the wavelength conversion layer being disposed on a surface of the reflective layer away from the reflective layer; Wherein, the difference percentage of the lattice parameters between any adjacent layers does not exceed 50%; And / or, the percentage difference in linear thermal expansion coefficient between any adjacent layers does not exceed 100%.

2. The wavelength conversion device according to claim 1, characterized in that: The difference percentage of the lattice parameters between any adjacent layers does not exceed 30%.

3. The wavelength conversion device according to claim 1, characterized in that: The difference percentage of the linear thermal expansion coefficient between any adjacent layers does not exceed 60%.

4. The wavelength conversion device according to claim 1, characterized in that: The first oxide transition layer is selected from at least one of aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, nickel oxide, and neodymium oxide.

5. The wavelength conversion device according to claim 1 or 4, characterized in that: The wavelength conversion device further includes a second oxide transition layer, and the second oxide transition layer is arranged between the reflective layer and the wavelength conversion layer.

6. The wavelength conversion device according to claim 5, characterized in that: The second oxide transition layer is selected from at least one of aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, hafnium oxide, niobium oxide, nickel oxide, and neodymium oxide.

7. The wavelength conversion device according to any one of claims 1 to 5, characterized in that: The reflective layer is a dielectric reflective layer, comprising a first dielectric film and a second dielectric film that are periodically and alternately stacked, wherein the first dielectric film and the second dielectric film each have at least one layer, and the refractive index of the first dielectric film is greater than the refractive index of the second dielectric film.

8. The wavelength conversion device according to claim 6, characterized in that: The first dielectric film is selected from at least one of titanium oxide, zirconium oxide, hafnium oxide, niobium oxide and neodymium oxide, and the second dielectric film is selected from at least one of aluminum oxide and silicon oxide.

9. The wavelength conversion device according to claim 1, characterized in that: The first metal oxide transition layer, the reflective layer and the wavelength conversion layer are formed by vapor deposition.

10. The wavelength conversion device according to claim 5 or 6, characterized in that: The second metal oxide transition layer is formed by vapor deposition.

11. A method for preparing a wavelength conversion device according to any one of claims 1 to 10, characterized in that: include: A substrate is provided, and a first oxide transition layer is sequentially deposited on a surface of one side of the substrate by vapor deposition; a reflective layer is formed on a surface of the first oxide transition layer away from the substrate, and a wavelength conversion layer is formed on a surface of the reflective layer away from the first oxide transition layer.

12. The method for preparing a wavelength conversion device according to claim 11, characterized in that: Before forming the wavelength conversion layer, a second oxide transition layer is formed on a surface of the reflective layer away from the first oxide transition layer by vapor deposition, and then the wavelength conversion layer is formed on a surface of the second oxide transition layer away from the reflective layer.

13. A light emitting device, characterized in that: The light emitting device comprises a laser light source and a wavelength conversion device as claimed in any one of claims 1 to 10, wherein the laser light source emits excitation light to excite the wavelength conversion device to emit stimulated light.

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