Diamond array type micro-porous heat dissipation substrate matched with multi-granularity fluorescent powder and design method thereof

Abstract

The application discloses a diamond array type micro-pore heat dissipation substrate suitable for multi-granularity fluorescent powder and a design method thereof. The diamond array type micro-pore design of the application is suitable for different particle size fluorescent powders, and maximum luminous efficiency is realized under specific incident power through optimization, which is a multi-dimensional, multi-physical field and fine coupling optimization process. The application utilizes the super-high thermal conductivity of diamond as a framework, and through the accurate design and optimization of the aperture, depth, shape, rib width, array mode and even the inner wall surface of the micro-pore in a region-by-region, self-adaptive and nanoscale manner, it is ensured that every particle size of fluorescent powder can obtain the best thermal management and light extraction conditions in the "exclusive" micro-pore environment, so that the maximum light energy can be released under the given excitation power.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of heat dissipation, and particularly relates to a diamond array type microporous heat dissipation substrate suitable for multiple particle size fluorescent powder and a design method thereof. BACKGROUND

[0002] Laser-excited phosphor as a new generation of high-brightness solid-state light source has great potential in the fields of automotive headlamps, projection and other fields. However, when high-power blue laser is incident on the phosphor, a significant amount of heat will be generated. If the heat dissipation is poor, the temperature rise of the phosphor will lead to a decrease in luminous efficiency (thermal quenching), brightness saturation, and even material degradation (Li Qian, Liu Yingying, Wang Yangan, et al. A wavelength conversion device: CN 110737085 A[P]. 2020.01.31). Therefore, an effective heat management structure is crucial for maintaining the high quantum efficiency and stable light emission of the phosphor. The conventional LED phosphor packaging has the phenomenon of "efficiency drop" under high driving, and it is difficult to withstand the high power density of laser light source. In order to solve the above problems, researchers have developed various high-thermal-conductivity substrates and heat dissipation structures to improve the heat dissipation performance of the phosphor light converter (such as: Yu, Z.; Zhao, J.; Yang, Z.; Mou, Y.; Zhang, H.; Xu, R.; Wang, Q.; Zeng, L.; Lei, L.; Lin, S.; Li, H.; Peng, Y.; Chen, D.; Chen, M. A Novel PiGF@Diamond Color Converter with a Record Thermal Conductivity for Laser-Driven Projection Display. Advanced Materials 2024, 2406147.). For example, in a remote phosphor light source, the introduction of a high-thermal-conductivity substrate, such as a copper and ceramic-based heat dissipation substrate, can significantly reduce the working temperature of the phosphor and delay the saturation point of light emission. The existing heat dissipation enhancement technologies will be introduced below, and an innovative diamond substrate micropore array structure will be proposed to further improve the light emission efficiency of the phosphor.

[0003] Single-crystal sapphire, ceramic, and metal substrates: Traditional LED packages often use sapphire, aluminum nitride (AIN), aluminum, copper, and other substrate materials, which have certain thermal conductivity and optical properties. For example, sapphire has high reflectivity and is resistant to high temperatures, but its thermal conductivity is only about 30 W / (m·K). In contrast, AIN ceramic, aluminum or copper substrate has higher thermal conductivity (tens to hundreds of W / (m·K)), which can alleviate the heat accumulation of phosphor to some extent. These substrates are relatively low in cost, but their thermal performance is limited and cannot fully meet the heat dissipation needs of ultra-high power laser lighting.

[0004] Diamond substrate: Artificially cultivated single-crystal diamond is considered an ideal heat dissipation substrate due to its extremely high thermal conductivity (>2000 W / (m·K)) and high transparency to visible light. Recently, there have been designs that use diamond as a phosphor-in-glass film (PiGF) substrate combined with different groove structures to achieve excellent results. Guo et al. reported that sintering La3Si6N11:Ce phosphor glass film on a transparent diamond sheet (PiGF@diamond) resulted in an equivalent thermal conductivity of the composite material of ≈599 W / (m·K), which is about 60 times that of traditional PiGF@sapphire (Guo, H.; Ding, X.; Li, J.; Yan, C.; Liu, X.; Li, Z. Opto-Thermal Enhancement of Phosphor-In-Glass Utilizing Nano Boron-Coated Copper Micropillar Substrate. IEEE Trans. Electron Devices 2024, 71 (12), 7621-7627.). Thanks to this ultra-high heat dissipation performance, the converter did not show light saturation even at a laser power density of 40.24 W / mm², and the output luminous flux could reach a maximum of 5602 lumens, with the phosphor temperature rise being suppressed at <130°C. This achievement shows that a diamond substrate can significantly improve the saturation threshold and brightness level of phosphor.

[0005] Although research on diamond materials for phosphor light sources has made progress, it is currently mostly focused on adding a thin layer of diamond film on the surface of the substrate to accelerate heat dissipation. For example, a patent by Guangfeng Technology in Shenzhen deposits a layer of transparent diamond film on the substrate or phosphor layer as a heat dissipation layer to quickly conduct the heat of the phosphor and reduce thermal saturation effects. This structure has been shown to prevent a decrease in luminous efficiency caused by overheating of the phosphor layer. However, in the above-mentioned solutions, diamond is mainly used as a flat heat dissipation layer, and the surface topography of the substrate is not specially designed. As the power continues to increase, how to further develop the heat dissipation potential of diamond and at the same time consider the optical efficiency of light output becomes a new direction for research and development.

[0006] Microstructure heat dissipation enhancement design: In addition to the material itself, it is also crucial for heat dissipation and light extraction. Some studies have made three-dimensional structures on high thermal conductivity substrates to expand the heat dissipation area, improve the heat flow path and optical path. For example, Ding et al. designed a three-dimensional copper micro-column array substrate, embedding the phosphor glass between the copper micro-columns to form a "metal-micro-column-glass" composite structure. The copper micro-columns significantly enhance internal heat transfer as micro-heat channels, and avoid light absorption by copper by coating an insulating boron nitride (BN) thin layer. Experiments show that compared with pure flat phosphor glass, the micro-column substrate reduces the converter temperature by about 21.9°C (at 8.48 W laser input), increases the phosphor saturation threshold by 68.5%, and increases the luminous efficiency by about 20.3%, and the maximum luminous flux by 68.5%. As can be seen, the introduction of three-dimensional structures such as micro-columns / micro-holes can simultaneously consider heat dissipation and optical performance, greatly improving the stability and brightness of high-power laser phosphor light sources.

[0007] Another related idea is to optimize the microstructure of the phosphor film and substrate interface. For example, some studies have adopted a "double-sided heat dissipation" sandwich structure: the phosphor glass film is sandwiched between sapphire with micro-tapered "moth eye" structure and high thermal conductivity ceramic to form a microstructure interface (Mou, Y.; Peng, Y.; Wang, X.; Liu, J.; Zhao, J.; Hao, Z.; Yu, Z.; Wang, Q.; Xu, J. Unique Sandwich and Microstructure Design of Phosphor-in-Glass Film for High Brightness Laser-Driven White Lighting. Journal of the European Ceramic Society 2024, 44 (4), 2408-2417.). This core-microstructure interface design not only improves light transmission and extraction (micro-tapered structure can reduce total reflection loss), but also allows the phosphor film to dissipate heat to both the top and bottom sides. Experiments obtained white light output of 5197 lm under 30 W / mm² laser excitation, with lower operating temperature and higher saturation threshold, significantly improving over traditional single-layer structures.

[0008] In summary, high thermal conductivity materials + heat dissipation microstructure is an effective way to improve the performance of laser phosphor light sources. Diamond, as the material with the most outstanding thermal conductivity, is expected to further break through the brightness limit if combined with a clever microstructure design. SUMMARY

[0009] The purpose of the present application is to solve the problems of limited light-emitting efficiency of fluorescent powder (uneven excitation light, which should be concentrated in the reflection angle) when laser high power and high energy density act together; the problems of reduced light-emitting efficiency of fluorescent powder (thermal quenching, light flux saturation, thermal aging, sintering and photobleaching, etc.) caused by poor heat dissipation of ordinary high-conductivity material substrate with a planar structure; and the problems of multi-scale optical scattering regulation and light-emitting stability (functional mapping relationship between fluorescent powder particle size, micro-pore diameter, depth, bottom structure and porosity of diamond bulk material), etc., and to propose a preparation of a periodic micro-pore array structure on a diamond substrate to simultaneously realize high-efficiency heat dissipation and high light output.

[0010] The technical solution for achieving the purpose of the present application is: on the one hand, a diamond array type micro-pore heat dissipation substrate suitable for multi-particle size fluorescent powder is provided, the substrate comprises diamond, the diamond is provided with an array type micro-pore, and the array type micro-pore can be adapted to the multi-particle size fluorescent powder, and at the same time, when the volume of the diamond is constant, the fluorescent powder can achieve the maximum heat transfer coefficient and the maximum light-emitting power.

[0011] On the other hand, a design method of the diamond array type micro-pore heat dissipation substrate is provided, the method comprises the following steps:

[0012] Step 1: under the condition of a given total diamond volume, decision variables in the design process are selected, including fluorescent powder parameters, array type micro-pore process parameters and fluorescent powder and micro-pore adaptation parameters;

[0013] Step 2: a certain type of fluorescent powder is selected, and its parameters are obtained; at the same time, a series of array type micro-pore process parameter schemes are self-defined and constructed, and fluorescent powder and micro-pore adaptation parameters are calculated;

[0014] Step 3: the adaptation index between the fluorescent powder parameters and each array type micro-pore process parameter scheme and the fluorescent powder and micro-pore adaptation parameters in step 2 is calculated;

[0015] Step 4: based on the adaptation index, the array type micro-pore process parameter scheme is screened to obtain the array type micro-pore process parameter scheme adapted to the fluorescent powder parameters in step 2;

[0016] Step 5: the maximum light-emitting power of each array type micro-pore process parameter scheme screened in step 4 is calculated, and the array type micro-pore process parameter scheme with the maximum light-emitting power as the maximum value is taken as the optimal array type micro-pore process parameter scheme.

[0017] Further, in step 1, the fluorescent powder parameters include particle size d p distribution, the micro-pore process parameters include hole shape S, hole diameter d, hole depth h, web width w and array type A, and the fluorescent powder and micro-pore adaptation parameters include porosity Φ.

[0018] Further, the calculation formula of the porosity Φ is:

[0019] ;

[0020] In the formula, is the cross-sectional area of the micropore, respectively, the length and width of the rectangular unit, the rectangular unit is a single rectangular unit uniformly divided into a rectangular array on the diamond surface, is the hole shape coefficient.

[0021] Further, the hole shape S includes a rectangle, a hexagon, and a circle; when the hole shape S is a rectangle, the hole shape coefficient ; when the hole shape S is a hexagon, the hole shape coefficient ; and when the hole shape S is a circle, the hole shape coefficient .

[0022] Further, the array mode A includes a rectangular array and a honeycomb array;

[0023] For the rectangular array, the following should be met:

[0024]

[0025] In the formula, n is the number of punching along the rectangular edge direction, is the equivalent diameter of the diamond surface in the rectangular edge direction, and d is the equivalent diameter of the micropore;

[0026] For the honeycomb array, the following should be met:

[0027]

[0028] In the formula, is the number of stacking layers of the micropore.

[0029] Further, the calculation formula of the fitting index in step 3 is:

[0030]

[0031] In the formula, represents the fitting index, are weight coefficients and the sum is 1, is a geometric packing fitting function, is a thermal diffusion fitting function, is a light excitation volume fitting function, which is respectively represented as:

[0032]

[0033]

[0034]

[0035] wherein, is the characteristic length of the hole cross section, λ is the best matching ratio, and α is the adjustment matching bandwidth; is the sum of the resistances of the diamond body thermal resistance, the fluorescent powder thermal resistance, and the contact thermal resistance of the joint surface, is the reference thermal resistance; is the laser penetration depth.

[0036] Further, step 4 screens the array type micro-hole process parameter scheme based on the adaptation index to obtain an array type micro-hole process parameter scheme adapted to the fluorescent powder parameters in step 2, and specifically includes:

[0037] Step 4-1, according to the adaptation index value, the array type micro-hole process parameter schemes are arranged in descending order;

[0038] Step 4-2, the array type micro-hole process parameter scheme with the adaptation index value greater than the preset first threshold value is selected;

[0039] Step 4-3, for the array type micro-hole process parameter scheme obtained in step 4-2, the values of all decision variables in the definition domain are scanned, and the array type micro-hole process parameter scheme that does not match the actual situation or the change of the evaluation index is less than the preset second threshold value is removed; the evaluation index includes the heat transfer coefficient of the diamond and the fluorescent powder after mixing, i.e., the equivalent heat transfer coefficient.

[0040] Further, the method further includes:

[0041] Step 6, the equivalent heat transfer coefficient of the optimal array type micro-hole process parameter scheme is calculated and output to an external terminal.

[0042] Further, the method further includes:

[0043] Step 7, steps 2 to 5 are repeatedly executed for several times to obtain multiple groups of design schemes, each group of design schemes including decision variables, an adaptation index, and an optimal array type micro-hole process parameter scheme;

[0044] Step 8, based on the multiple groups of design schemes, a machine learning algorithm is used for iterative optimization until an optimization condition is met, and a final array type micro-hole process parameter scheme is output.

[0045] Compared with the prior art, the present application has the following advantages:

[0046] (1) The diamond array type micro-pore design of the present application is suitable for different particle size fluorescent powder, and the maximum luminous efficiency is achieved under a specific incident power by optimization, which is a multi-dimensional, multi-physical field and fine coupling optimization process. It uses the super high thermal conductivity of diamond as the framework, and through the accurate design and optimization of the pore size, depth, shape, rib width, array method and even the inner wall of the micro-pore in different regions, self-adaption and nanoscale, to ensure that each particle size of fluorescent powder can obtain the best thermal management and light extraction conditions in its "exclusive" micro-pore environment, so as to release the maximum light energy under the given excitation power.

[0047] (2) The existing technology uses diamond only as a planar heat diffusion layer, although it can reduce the temperature rise of fluorescent powder to a certain extent, but the heat conduction path is limited to two-dimensional plane, and it is difficult to cope with local heat accumulation under high power density of laser. The present application constructs a three-dimensional heat dissipation channel by preparing a periodic micro-pore array on the diamond substrate, so that the heat generated by the fluorescent powder can be more efficiently diffused to the substrate and the external environment, greatly reducing the equivalent thermal resistance and significantly improving the heat dissipation capacity, thereby delaying the thermal quenching phenomenon and maintaining high light flux output.

[0048] (3) The existing technology usually uses uniform particle size fluorescent powder or single pore size design, resulting in non-dense filling, high thermal resistance and low light scattering efficiency. The present application first proposes a quantitative matching method of multi-particle size fluorescent powder and pore structure parameters, through optimizing the pore size, depth, porosity and array method, different particle size fluorescent powder is matched and filled in the same substrate in a partitioned and multi-scale manner, ensuring the close packing and uniform distribution of particles, improving the heat conduction path and improving the photon excitation and escape efficiency, so as to realize higher luminous efficiency and lower temperature rise under high power laser action.

[0049] (4) The existing technology improves the single performance of heat dissipation or optics, and lacks systematic optimization considering both. The present application establishes a complete multi-objective optimization design process, uses the combination of algorithm optimization and multi-physical field coupling simulation to balance the equivalent thermal resistance and light output power, and obtains the optimal design parameter combination; and combines the low-damage punching, fluorescent powder embedding and other process flows, so that the optimization result has engineering implementability. Therefore, the present application realizes the improvement of optical efficiency while maintaining the super high heat dissipation performance, and has significant overall performance advantage.

[0050] The present application will be described in further detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 It is a schematic diagram for controlling the overall structure parameters of the diamond substrate.

[0052] Figure 2A flow chart of the design method of the diamond array micro-porous heat dissipation substrate of the present application. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solutions and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0054] It should be noted that if the present application examples involve directionality indication (such as up, down, left, right, front, back, etc.), the directionality indication is only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directionality indication also changes accordingly.

[0055] In addition, if the present application examples involve the description of "first", "second", etc., the description of "first", "second", etc. is only for description purpose and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features with "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of a person skilled in the art, and when the combination of technical solutions appears to be contradictory or unachievable, it should be considered that the combination of technical solutions does not exist and is not within the protection scope required by the present application.

[0056] In one embodiment, a diamond array micro-porous heat dissipation substrate suitable for multi-particle-size fluorescent powder is provided, the substrate comprising diamond, the diamond being provided with array micro-pores, and the array micro-pores being suitable for multi-particle-size fluorescent powder, and at the same time, when the volume of the diamond is constant, the fluorescent powder can achieve the maximum heat transfer coefficient and the maximum luminous power.

[0057] Here, "suitable" does not mean fixing a pore size to adapt to all particle sizes of fluorescent powder, but means a regional, multi-scale pore size design, which is the most direct and efficient method to adapt to multi-particle-size fluorescent powder. On the same diamond substrate, the substrate can be divided into several functional regions. The design logic is to fill different particle sizes of fluorescent powder in coordination with different pore sizes according to the thermal load distribution or the desired light emitting characteristics of different regions. For example, in the center region with the highest laser power density, it may be necessary to fill large-particle-size fluorescent powder with excellent heat conduction performance and relatively small stack thermal resistance, and at the same time, to fill it with small pore size; but in the peripheral region, a small amount of small-particle-size fluorescent powder should be added while filling it with large-particle-size fluorescent powder and at the same time, to fill it with relatively large pore size.

[0058] In one embodiment, in combination with Figure 2, a design method of a diamond array type micro-hole heat dissipation substrate adapted to multi-granularity fluorescent powder is provided, the method comprising the following steps:

[0059] Step 1, under the condition of a given total diamond volume, selecting decision variables in the design process, including fluorescent powder parameters, array type micro-hole process parameters and fluorescent powder and micro-hole adaptation parameters;

[0060] Step 2, selecting a certain type of fluorescent powder and obtaining its parameters; at the same time, customizing a series of array type micro-hole process parameter schemes and calculating fluorescent powder and micro-hole adaptation parameters;

[0061] Step 3, calculating the adaptation index between the fluorescent powder parameters and each array type micro-hole process parameter scheme and the fluorescent powder and micro-hole adaptation parameters in step 2;

[0062] Step 4, screening the array type micro-hole process parameter schemes based on the adaptation index to obtain the array type micro-hole process parameter scheme adapted to the fluorescent powder parameters in step 2;

[0063] Step 5, calculating the maximum luminous power of each array type micro-hole process parameter scheme screened in step 4, and taking the array type micro-hole process parameter scheme with the maximum luminous power as the maximum value as the optimal array type micro-hole process parameter scheme.

[0064] Further, in one of the embodiments, in step 1, in combination with Figure 1 , the fluorescent powder parameters include particle size d p distribution, the micro-hole process parameters include hole shape S, hole diameter d, hole depth h, web width w and array type A, and the fluorescent powder and micro-hole adaptation parameters include porosity Φ.

[0065] Here, the decision variables are as shown in Table 1.

[0066] Table 1 Explanation of decision variables

[0067] Parameter Physical meaning Modeling approach Pore shape (S) Control arrangement density and thermal conduction channel connectivity, control porosity Direct: circle, square, hexagon Pore size (D) Determine the degree of adaptation of phosphor particle size, porosity Match the design of particle size distribution Pore depth (H) Determining the degree of phosphor build-up ϕ packing 、 Equivalent thermal resistance R eq 、 Volume fraction ϕ fill And the number of stacked layers of phosphor N layers ]]> Through hole / blind hole; consider thermal resistance model Porosity (P) Thermal conduction skeleton reservation and filling volume trade-off Explicit formula derivation + FEA auxiliary Rib width (W) Control the distance between the holes, affect the integrity of the thermal network Implicit in the function of the arrangement way + Array way (A) Determine the number of holes and the shape of the thermal conduction path per unit area Matrix / honeycomb array Particle size d p Distribution Filling and stacking strategy under multi-granularity distribution Need distribution matching strategy (large / small particle classification)

[0068] Preferably, in some embodiments, the calculation formula of the porosity Φ is:

[0069]

[0070] In the formula, is the cross-sectional area of the micro-hole, are the length and width of the rectangular unit respectively, the rectangular unit being a single rectangular unit uniformly divided from the diamond surface into a rectangular array, is the hole shape coefficient.

[0071] Here, in particular, if the rectangular unit is square, The calculation formula of porosity Φ is:

[0072]

[0073] Here, the hole shape S includes rectangle, hexagon and circle; when the hole shape S is rectangle, the hole shape coefficient is ; when the hole shape S is hexagon, the hole shape coefficient is ; and when the hole shape S is circle, the hole shape coefficient is .

[0074] Preferably, in some embodiments, the array mode A includes rectangular array and honeycomb array.

[0075] For the rectangular array, the following should be satisfied:

[0076]

[0077] to achieve reasonable spatial geometric feature arrangement.

[0078] In the formula, n is the number of punching along the rectangular edge direction, is the equivalent diameter of the diamond surface in the rectangular edge direction, and d is the equivalent diameter of the micro-hole.

[0079] For the honeycomb array, the following should be satisfied:

[0080]

[0081] to achieve geometric continuity in space.

[0082] In the formula, The number of stacked layers of micro-holes is usually odd.

[0083] Further, in one of the embodiments, the calculation formula of the fitting index in step 3 is:

[0084]

[0085] In the formula, represents the fitting index, are weight coefficients and their sum is 1, is the geometric packing fitting function, is the thermal diffusion fitting function (the design goal is to make the thermal resistance as small as possible), is the light excitation volume fitting function (it is hoped that the filling volume V phos of the fluorescent powder is located as much as possible within the laser penetration depth h excite ).

[0086] Here, the weight coefficients are defined according to the actual application (heat dominated / light dominated). Preferably, the weight ω1=ω2=0.4, ω3=0.2 is set. If the heat problem is serious, ω2 can be increased.

[0087] Here, the adaptation index comprehensively reflects the matching effect of the following three mechanisms: geometric matching: whether the particle size is suitable for filling the hole and whether it forms a dense packing; thermal adaptation: whether the structure provides a good heat diffusion channel and low thermal resistance; optical adaptation: whether the hole structure can provide sufficient excitation light excitation volume and avoid thermal quenching.

[0088] Here, preferably, the adaptation function of each sub-item is represented as:

[0089]

[0090]

[0091]

[0092] In the formula, is the characteristic length of the hole cross section, and the optimal ratio is usually d p ∈[0.4, 0.6] interval, λ is the optimal matching ratio (usually 0.5), and α is the adjustment matching bandwidth (usually 20-40); is the sum of the resistances of the diamond body thermal resistance, the fluorescent powder thermal resistance, and the contact thermal resistance of the combined surface, is the reference thermal resistance; is the laser penetration depth. It should be noted that when all the decision variables are a fixed value, R total is the equivalent thermal resistance R eq , and its calculation method is based on the Maxwell-Eucken mixing calculation formula or the multi-layer material finite element calculation model.

[0093] Here, the geometric packing adaptation function is not limited to the above Gaussian type, but can also be other types of distribution, such as inverse parabolic function, inverse Lorentz function, piecewise function and triangular function, etc.

[0094] Here, the light excitation volume adaptation function shows that when the hole is too deep, i.e. h excite , the excess volume of fluorescent powder cannot be effectively excited, causing material waste, and the porosity Φ directly reflects the upper limit of the filling volume.

[0095] Further, in one embodiment, the step 4 of screening the array type micro-pore process parameter scheme based on the adaptation index to obtain the array type micro-pore process parameter scheme adapted to the fluorescent powder parameters in step 2, specifically includes:

[0096] Step 4-1, rank the array micro-hole process parameter schemes in descending order according to the fitness index value;

[0097] Step 4-2, select the array micro-hole process parameter scheme with the fitness index value greater than the preset first threshold value;

[0098] Step 4-3, for the array micro-hole process parameter scheme obtained in step 4-2, scan the values of all decision variables in the defined domain, and eliminate the array micro-hole process parameter scheme that does not conform to the actual situation or the change of the evaluation index is less than the preset second threshold value; the evaluation index includes the heat transfer coefficient of the mixed diamond and phosphor, i.e. the equivalent heat transfer coefficient.

[0099] Further, in one of the embodiments, the method further comprises:

[0100] Step 6, calculate the equivalent heat transfer coefficient of the optimal array micro-hole process parameter scheme and output to an external terminal.

[0101] Further, in one of the embodiments, the method further comprises:

[0102] Step 7, repeat steps 2 to 5 several times to obtain multiple groups of design schemes, each group of design schemes including decision variables, fitness index and optimal array micro-hole process parameter scheme;

[0103] Step 8, based on the multiple groups of design schemes, iteratively optimize using a machine learning algorithm until the optimization condition is met, and output the final array micro-hole process parameter scheme.

[0104] Here, the machine learning algorithm uses but is not limited to neural network (NN), Gaussian process regression (GPR) or support vector regression (SVR), NSGA-II or NSGA-III, etc.

[0105] Here, the specific process of step 8 is as follows:

[0106] (1) Initialize the population, and regard each group of design schemes as an individual.

[0107] (2) Evaluate each individual, calculate the total equivalent thermal resistance R eq (equivalent heat transfer coefficient) and under the current type of phosphor and diamond hole parameter (array micro-hole process parameter) through phosphor filling rate calculation, heat conduction simulation model and optical simulation model.

[0108] (3) Non-dominated sorting, sort the population according to R eq and , find the non-dominated solution (i.e. part of the Pareto optimal solution set).

[0109] (4) Calculate crowding distance, evaluate the uniformity of non-dominated solutions on the Pareto front.

[0110] (5) Selection, crossover, mutation, based on ranking and crowding distance, select better individuals for genetic operation to generate the next generation population.

[0111] (6) Iteration, repeat (2) to (5) until the optimization condition is met.

[0112] In addition, in the evaluation stage, a surrogate model constructed by machine learning can be used to replace the time-consuming physical field simulation. A small number of representative points are selected in the design space for high-precision physical simulation (such as FEA / DEM). Using neural network (NN), Gaussian process regression (GPR) or support vector regression (SVR) and other machine learning methods, learn the nonlinear mapping relationship from decision variables to R eq and . Finally, to accelerate optimization, in most iterations of the optimizer, use the trained surrogate model for fast performance prediction, and only in key areas or areas with high uncertainty, call the real physical simulation.

[0113] The design idea flow of the present application is described in detail below.

[0114] Suppose the volume of diamond V 总 is fixed (for example, 1 x 10 -6 m³), h = 100 μm, A = V / h, the incident power of the light source P0=10W, the ambient temperature T amb =300 K, the maximum illumination temperature T max =373 K, the thermal conductivity of diamond k diamond =2000 W / m·K, the thermal conductivity of phosphor k phosphor =5 W / m·K, the thermal decay constant T0=50 K, and the "[]" symbol is used to represent the attribute setting of a certain parameter, which is convenient for programming.

[0115] Step 1: Input parameter definition and constraint setting

[0116] a) Variables:

[0117] Shape: ['circle','square', 'hexagon'];

[0118] Array mode: ['square', 'hex'];

[0119] Pore diameter d: continuous variable, range [3 mean(d p ), 50 μm].

[0120] Pore spacing a: continuous, [d+1 μm, 100 μm] (ensure w=a-d≥1 μm strength limit).

[0121] Depth: ['through' (depth=h), 'blind' (depth=0.5-0.9h)].

[0122] Particle size d p : distribution type (e.g. normal distribution μ=2 μm, σ=1 μm), or fixed value.

[0123] b) Constraints:

[0124] Process: d≥1 μm (limited by processing technology); Φ eff <0.8 (limited by structural stability).

[0125] Performance: T<T max ; f fill >0.8 (limited by filling threshold).

[0126] Quantitative matching initial value: d≥3d p (minimum stack assumption); a≥d+w min .

[0127] Example input: d p ~N(2,1), shape=circle, array=square.

[0128] Input logic: use dictionary to store variable space, grid discrete or continuous optimization preparation. The constraint process should be screened first to avoid invalid calculation.

[0129] Step 2: Build a physical model

[0130] a) Construct a geometric mapping about Φ: parameters (S, S', A, d, a) → porosity.

[0131] Calculation formula: circle-square: πd² / (4a²); hex-hex: (3 / 4)d² / a², etc.

[0132] Coefficient derivation: A hole / A cell ; Method: standard geometric area → density division.

[0133] b) Particle packing model (d p -d function matching, i.e. f fill ): build Gaussian function + Monte Carlo method.

[0134] f fill (d p, d) =exp[-(d p / d-0.25)^2 / (2*0.5^2)](If r opt =0.25, therefore d opt =4d p ).

[0135] d p Distribution: f fill _avg=(1 / N)Σf fill (d p(i) d), Let N=1000 and perform Monte Carlo sampling to simulate particle entry into the pore. If random_pos <d-d p(i) Then it is considered a success.

[0136] Impact Analysis: When d=4d p At that time, f fill ≈1, Φ eff The maximum value is obtained when d < 2d. p At that time, f fill <0.5 indicates an increase in the air gap, and R thermal ≈1 / k air k eff Reduce by 50%; when d>10d p At that time, f fill k approaches 1 but has a longer thermal path. eff Indirectly reduced, therefore k can be used. eff Correction, i.e., k eff =1 / (1+(d / a)^2).

[0137] The derivation logic of the filling model: The Gaussian equation is derived from the energy barrier probability, while Monte Carlo adds randomness to the particle distribution and ensures quantitative accuracy (e.g., variance < 5%).

[0138] c) Thermal conductivity model (k eff ): Φ eff =Φ aera *f fill *(depth / h).

[0139] Bruggeman:Φ eff (k phosphor -k eff ) / (k phosphor +2k eff )+(1-Φ eff (k) diamond -k eff ) / (k diamond +2k eff )=0.

[0140] Equation solving: numerical root finding (e.g. scipy.root_scalar); Blind-hole correction equation: k eff = k eff + (1-depth / h)*k diamond (including bottom path addition). For example, when Φ eff = 0.5, k eff ≈ 521.7 W / m·K.

[0141] d) Light emission model (P out ): T = T amb + P0*h / (k eff *V 总 / h); η = exp[-(T-T amb ) / T0]; P out = Φ eff *V 总 *η*scale (scale is the excitation power factor, normalized = 1).

[0142] Influencing factors: high Φ eff value means small V 总 , while k eff decreases, temperature rises, and η decreases, so multiple factors need to be considered in the matching process.

[0143] Design logic: model level progression, i.e. geometry → micro-filling → macro performance, with closed-form / numerical solutions for each, facilitating quantitative mapping.

[0144] Step 3: Simulation and calculation chain

[0145] For parameter combinations, the calculation chain is: Monte Carlo filling → porosity Φ → equivalent thermal conductivity k eff → temperature T → light emission power P out .

[0146] For example, when d p = 18 μm, and a hexagonal-hybrid array is used, the d hierarchical range is 36-72 μm, Cr3C2 coating, gradual via (depth changes from 100 μm to 60 μm, average depth 80 μm), Φ area is optimized to Φ area ≈ 0.75 (hexagonal-hybrid packing, coating enhances effective area by about 10%); f fill ≈ 0.92 (based on Gaussian model, average d ≈ 3d p , r opt = 0.25, σ = 0.5, hierarchical adaptation multi-d p istribution, average value obtained using Monte Carlo simulation, where N = 1000); Φeff =Φ area ×f fill ×(depth avg / h)≈0.75×0.92×0.8≈0.55;k eff ≈340 W / m·K (calculated using the Bruggeman model, with coating correction not exceeding 20%); T≈300+10×(1-0.5) / (340×0.01 / 10 -4 )≈300+0.00015 K (Therefore, ΔT is extremely small, and its effect may be more significant under actual high power density); P out ∝0.55×exp[-(T-300) / 50]≈0.55 (normalization process, maximum error is about 22%, minimizing thermal quenching). It is important to note that calculating this chain reaction requires ensuring stable tracking.

[0147] Step 4: Multi-objective optimization

[0148] a) Relevant Algorithm: NSGA-II (Genetic Algorithm, pop=50, gen=20), Objective: Maximize k eff and the maximum P out The variable vector is [d, a, depth, shape_idx, array_idx]. The penalty function is: if T>T max or f fill <0.8, obj=-inf. Use the deap library or scipy.optimize to implement the Pareto front (e.g., a 100-solution set).

[0149] b) Quantitative matching output: Frontier points such as (d=4d) p (a=1.25d, hex array) → Φ eff =0.5, k eff =520, P out =0.5.

[0150] c) Design logic: NSGA-II processes non-convex spaces and generates matching "spectrums"; it is more efficient than grid search (accelerated by surrogate models such as Gaussian Process).

[0151] Step 5: Output and Sensitivity Analysis

[0152] a) Output items: Best matching table, Pareto graph (e.g., k-values) eff -P out Curves), parametric relationships (such as d) opt =4d p ±σ), etc.

[0153] b) Parameter sensitivity: numerical differentiation, e.g. ∂P out / ∂d≈(P out (d+Δ)-P out (d)) / Δ; for example, when d sensitivity is high, the value increases by 10% when d out increases by 15%.

[0154] c) Result presentation: for example, optimal match in ideal case: shape S = hexagon, array type A = hex, d = 8 μm (4d p ), a = 10 μm, via, k eff = 550, P out = 0.727.

[0155] d) Core logic: analysis guides iteration (for example, when ∂ / ∂d p is high, prioritize uniformizing d p ).

[0156] In one embodiment, a design system for adapting diamond array micro-hole heat dissipation substrate for multi-granularity phosphor powder is provided, the system comprising sequentially executed:

[0157] A first module for implementing: under the condition of a given total diamond volume, selecting decision variables in the design process, including phosphor parameters, array micro-hole process parameters, and phosphor and micro-hole adaptation parameters;

[0158] A second module for implementing: selecting a certain type of phosphor and obtaining its parameters; at the same time, customizing a series of array micro-hole process parameter schemes and calculating phosphor and micro-hole adaptation parameters;

[0159] A third module for implementing: calculating the adaptation index between the phosphor parameters output by the second module and each array micro-hole process parameter scheme and the phosphor and micro-hole adaptation parameters;

[0160] A fourth module for implementing: screening array micro-hole process parameter schemes based on the adaptation index to obtain array micro-hole process parameter schemes adapted to the phosphor parameters in the second module;

[0161] A fifth module for implementing: calculating the maximum luminous power of each array micro-hole process parameter scheme screened by the fourth module, and taking the array micro-hole process parameter scheme with the maximum luminous power as the maximum value as the optimal array micro-hole process parameter scheme.

[0162] The specific limitations of the design system of the diamond array micro-porous heat dissipation substrate adapted to the multi-particle-size phosphor powder can refer to the limitations of the design method of the diamond array micro-porous heat dissipation substrate adapted to the multi-particle-size phosphor powder, which will not be repeated here. Each module in the design system of the diamond array micro-porous heat dissipation substrate can be realized by software, hardware, or a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0163] In one embodiment, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the following when executing the computer program:

[0164] Step 1. Under the condition of a given total diamond volume, select the decision variables in the design process, including phosphor parameters, array micro-porous process parameters, and phosphor-micro-porous adaptation parameters;

[0165] Step 2. Select a certain type of phosphor and obtain its parameters; at the same time, customize a series of array micro-porous process parameter schemes and calculate the phosphor-micro-porous adaptation parameters;

[0166] Step 3. Calculate the adaptation index between the phosphor parameters and each array micro-porous process parameter scheme, and the phosphor-micro-porous adaptation parameters in step 2;

[0167] Step 4. Based on the adaptation index, screen the array micro-porous process parameter schemes to obtain the array micro-porous process parameter scheme adapted to the phosphor parameters in step 2;

[0168] Step 5. Calculate the maximum luminous power of each array micro-porous process parameter scheme screened in step 4, and take the array micro-porous process parameter scheme with the maximum luminous power as the optimal array micro-porous process parameter scheme.

[0169] The specific limitations of each step can refer to the limitations of the design method of the diamond array micro-porous heat dissipation substrate adapted to the multi-particle-size phosphor powder, which will not be repeated here.

[0170] In one embodiment, a computer readable storage medium is provided, which stores a computer program, wherein the computer program is executed by a processor to implement:

[0171] Step 1. Under the condition of a given total diamond volume, select the decision variables in the design process, including phosphor parameters, array micro-porous process parameters, and phosphor-micro-porous adaptation parameters;

[0172] Step 2, select a certain type of phosphor and obtain its parameters; at the same time, custom build a series of array type micro-hole process parameter schemes, and calculate the phosphor and micro-hole adaptation parameters;

[0173] Step 3, calculate the adaptation index between the phosphor parameters in step 2 and each array type micro-hole process parameter scheme, and the adaptation index between the phosphor and micro-hole adaptation parameters;

[0174] Step 4, screen the array type micro-hole process parameter scheme based on the adaptation index to obtain the array type micro-hole process parameter scheme adapted to the phosphor parameters in step 2;

[0175] Step 5, calculate the maximum luminous power of each array type micro-hole process parameter scheme screened in step 4, and take the array type micro-hole process parameter scheme with the maximum luminous power as the optimal array type micro-hole process parameter scheme.

[0176] For the specific definition of each step, please refer to the definition of the design method of the diamond array type micro-hole heat dissipation substrate adapted to the multi-granularity phosphor body in the above, which will not be repeated here.

[0177] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for designing a diamond array micro-hole heat dissipation substrate suitable for multi-granularity fluorescent powder, characterized in that, The method comprises the following steps: Step 1, under the condition of a given total diamond volume, selecting decision variables in the design process, including phosphor parameters, arrayed micro-hole process parameters, and phosphor-micro-hole adaptation parameters; Step 2, selecting a certain type of phosphor and obtaining its parameters; at the same time, defining and constructing a series of arrayed micro-hole process parameter schemes, and calculating phosphor-micro-hole adaptation parameters; Step 3, calculating the adaptation index between the phosphor parameters in Step 2 and each arrayed micro-hole process parameter scheme, and the phosphor-micro-hole adaptation parameters; Step 4, screening the arrayed micro-hole process parameter schemes based on the adaptation index to obtain the arrayed micro-hole process parameter scheme adapted to the phosphor parameters in Step 2; Step 5, calculating the maximum luminous power of each arrayed micro-hole process parameter scheme screened in Step 4, and taking the arrayed micro-hole process parameter scheme with the maximum luminous power as the optimal arrayed micro-hole process parameter scheme; In step 1, the fluorescent powder parameters include particle size d p Distribution, the micro-hole process parameters include hole shape S, hole diameter d, hole depth h, web width w and array mode A, and the fluorescent powder and micro-hole adaptation parameters include porosity Φ. The calculation formula of the porosity Φ is: ； wherein is the cross-sectional area of the micropore, are the length and width, respectively, of a rectangular element that uniformly divides the diamond surface into a rectangular array of individual rectangular elements, is the pore shape factor; The hole shape S includes a rectangle, a hexagon, and a circle; when the hole shape S is a rectangle, the hole shape coefficient ; when the hole shape S is a hexagon, the hole shape coefficient ; and when the hole shape S is a circle, the hole shape coefficient ; The array mode A includes a rectangular array and a honeycomb array; For the rectangular array, the following should be met: ； In the formula, n is the number of perforations in the rectangular edge direction, D is the equivalent diameter of the diamond surface in the rectangular edge direction, and d is the equivalent diameter of the micro-holes. For the honeycomb array, the following should be met: ； In the formulae, the number of stacked layers of micropores.

2. The design method of claim 1, wherein The calculation formula of the adaptation index in Step 3 is: ； wherein represents an adaptation index, are weight coefficients and sum to 1, is a geometric packing adaptation function, is a thermal diffusion adaptation function, is a light excitation volume adaptation function, respectively represented as: ； ； ； In the formula, is the pore cross-sectional characteristic length, λ is the best matching ratio, and α is the adjustment matching bandwidth; is the sum of the resistance values after considering the thermal resistance of the diamond body, the thermal resistance of the fluorescent powder body, and the contact thermal resistance of the combined surface, is the reference thermal resistance; is the laser penetration depth.

3. The method of designing according to claim 1, wherein, Step 4, the screening of the arrayed micro-hole process parameter schemes based on the adaptation index to obtain the arrayed micro-hole process parameter scheme adapted to the phosphor parameters in Step 2, specifically comprises: Step 4-1, arranging each arrayed micro-hole process parameter scheme in descending order according to the adaptation index value; Step 4-2, selecting the arrayed micro-hole process parameter scheme with the adaptation index value greater than a preset first threshold value; Step 4-3, scanning the values of all decision variables in the definition domain for the arrayed micro-hole process parameter scheme obtained in Step 4-2, and eliminating the arrayed micro-hole process parameter schemes that do not match the actual situation or have a change in the evaluation index less than a preset second threshold value; the evaluation index includes the heat transfer coefficient of the mixture of diamond and phosphor, i.e., the equivalent heat transfer coefficient.

4. The method of designing according to claim 3, wherein, The method further comprises: Step 6, calculating the equivalent heat transfer coefficient of the optimal arrayed micro-hole process parameter scheme and outputting to an external terminal.

5. The method of designing according to claim 4, wherein, The method further comprises: Step 7, repeating Steps 2 to 5 for several times to obtain multiple groups of design schemes, each group of design scheme comprising decision variables, an adaptation index, and an optimal arrayed micro-hole process parameter scheme; Step 8, based on the multiple groups of design schemes, using a machine learning algorithm for iterative optimization until the optimization condition is met, and outputting the final arrayed micro-hole process parameter scheme.

6. A design system for a diamond array micro-hole heat dissipation substrate with adapted multi-granularity fluorescent powder based on the method of any one of claims 1 to 5, characterized in that, The system comprises the following modules executed in sequence: A first module for realizing: under the condition of a given total diamond volume, selecting decision variables in the design process, including phosphor parameters, arrayed micro-hole process parameters, and phosphor-micro-hole adaptation parameters; A second module for realizing: selecting a certain type of phosphor and obtaining its parameters; at the same time, defining and constructing a series of arrayed micro-hole process parameter schemes, and calculating phosphor-micro-hole adaptation parameters; A third module for realizing: calculating the adaptation index between the phosphor parameters output by the second module and each arrayed micro-hole process parameter scheme, and the phosphor-micro-hole adaptation parameters; A fourth module configured to implement: screening array type micro-hole process parameter schemes based on the adaptation index to obtain an array type micro-hole process parameter scheme adapted to the phosphor parameters in the second module; A fifth module configured to implement: calculating the maximum luminous power of each array type micro-hole process parameter scheme screened by the fourth module, and taking the array type micro-hole process parameter scheme with the maximum luminous power as the optimal array type micro-hole process parameter scheme.

7. A computer device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor implements the computer program to implement the method of any one of claims 1 to 5.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the method of any one of claims 1 to 5.

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