Graphite disks for MOCVD equipment and their preparation method; MOCVD equipment

Abstract

The application relates to the technical field of optoelectronic manufacturing, and particularly discloses a graphite disc for an MOCVD device, a preparation method of the graphite disc and the MOCVD device. The graphite disc comprises a graphite disc base body provided with a front surface and a back surface, a plurality of accommodating grooves arranged on the front surface of the graphite disc base body, and a temperature adjusting layer arranged on a first region of the back surface of the graphite disc base body, wherein the first region is included in a normal projection region of the accommodating grooves on the back surface. The temperature adjusting layer and the graphite disc base body satisfy the following relationship: wherein is the radiation absorption rate of the graphite disc base body in a high-temperature stage, is the radiation absorption rate of the temperature adjusting layer in the high-temperature stage, is the radiation absorption rate of the graphite disc base body in a low-temperature stage, and is the radiation absorption rate of the temperature adjusting layer in the low-temperature stage. The temperature range of the low-temperature stage is 700 DEG C to 900 DEG C, and the temperature range of the high-temperature stage is 1000 DEG C to 1200 DEG C. The application can improve the wavelength uniformity and yield of LEDs.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic manufacturing technology, and in particular to a graphite disk for MOCVD equipment, its preparation method, and the MOCVD equipment. Background Technology

[0002] MOCVD (Modular CVD) is a core process in LED fabrication. During MOCVD, a graphite disk is typically used as the substrate to support the epitaxial wafer. The uniformity of the surface temperature distribution directly affects various LED performance characteristics, especially wavelength uniformity and yield.

[0003] On the other hand, for GaN-based epitaxial layers on sapphire substrates (with InGaN-GaN multi-quantum-well layers as the active region), due to the thermal mismatch between the epitaxial layer and the sapphire substrate, the epitaxial wafer will warp and deform (become concave) during the high-temperature growth stage (e.g., when growing undoped GaN layers or N-type GaN layers, the temperature is around 1000℃~1200℃). This results in a high temperature in the middle of the epitaxial wafer and a low temperature at the edge, causing a yield loss problem for LED chips in the edge region. Furthermore, the temperature unevenness also leads to a reduction in wavelength uniformity.

[0004] To address this issue, one solution is to design the bottom of the groove in the graphite disk to be slightly concave and curved to match the shape after high-temperature warping. However, at low temperatures (such as when growing InGaN-GaN multi-quantum-well layers, at temperatures of 700℃~900℃), the improved flatness of the epitaxial wafer can actually lead to unevenness, with lower temperatures in the center and higher temperatures at the edges. This results in poor wavelength uniformity and low yield. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a graphite disk for MOCVD equipment and a method for preparing the same, which can improve the wavelength uniformity and yield of LEDs.

[0006] Another technical problem that the present invention needs to solve is to provide an MOCVD device.

[0007] To address the above problems, the present invention provides a graphite disk for an MOCVD apparatus, comprising: A graphite disk substrate having a front and a back side; Multiple receiving slots are provided on the front side of the graphite disk substrate; A temperature-regulating layer is disposed in a first region on the back side of the graphite disk substrate, the first region being included in the orthographic projection region of the receiving groove on the back side; The temperature-regulating layer and the graphite disk substrate conform to the following relationship:

[0008] in, The radiation absorptivity of the graphite disk substrate at high temperatures. The radiation absorptivity of the temperature-regulating layer during high-temperature stages. The radiation absorptivity of the graphite disk substrate at low temperatures. The radiation absorptivity of the temperature-regulating layer at low temperatures; The temperature range of the low-temperature stage is 700℃~900℃, and the temperature range of the high-temperature stage is 1000℃~1200℃.

[0009] As an improvement to the above technical solution, the cross-section of the temperature regulating layer is circular, and the center of the orthographic projection of the temperature regulating layer on the back side coincides with the center of the orthographic projection of the receiving groove on the back side. The diameter of the temperature-regulating layer is smaller than the diameter of the receiving tank.

[0010] As an improvement to the above technical solution, the thickness of the temperature-regulating layer decreases along the radial direction away from its center.

[0011] As an improvement to the above technical solution, the diameter of the temperature regulating layer is 60% to 90% of the diameter of the receiving groove.

[0012] As an improvement to the above technical solution, the thickness of the temperature-regulating layer at point i is determined according to the following formula:

[0013] Among them, T i Let r be the thickness of the temperature-regulating layer at point i. i Let R be the radius of the temperature-regulating layer at radial position i, and T be the radius of the temperature-regulating layer. max Where n is the maximum thickness of the temperature-regulating layer; T max The value of is in the range of 20nm to 1000nm, and the value of n is in the range of 0.5 to 2.

[0014] As an improvement to the above technical solution, the temperature regulating layer is composed of (M1) v M2 w M3 x M4 y M5 z Made of N, M1, M2, M3, M4, and M5 are all selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, and Si, and M1, M2, M3, M4, and M5 are all different; v+w+x+y+z=1.

[0015] As an improvement to the above technical solution, M1 is Al, and the value of v ranges from 0.1 to 0.2; M2 is Cr, and the value of w ranges from 0.15 to 0.25; M3 is Ta, and the value of x ranges from 0.2 to 0.3; M4 represents Ti, and the value of y ranges from 0.15 to 0.25; M5 is Zr, and the value of z ranges from 0.15 to 0.25.

[0016] Accordingly, the present invention also discloses a method for preparing a graphite disk for an MOCVD device, which includes: A graphite disk substrate is provided; the graphite disk substrate has a front side and a back side, and the front side has a plurality of receiving grooves; A temperature-regulating layer is formed on the graphite disk substrate; The temperature-regulating layer is disposed in a first region on the back side of the graphite disk substrate, and the first region is included in the orthographic projection region of the receiving groove on the back side; the temperature-regulating layer and the graphite disk substrate conform to the following relationship:

[0017] in, The radiation absorptivity of the graphite disk substrate at high temperatures. The radiation absorptivity of the temperature-regulating layer during high-temperature stages. The radiation absorptivity of the graphite disk substrate at low temperatures. The radiation absorptivity of the temperature-regulating layer at low temperatures; The temperature range of the low-temperature stage is 700℃~900℃, and the temperature range of the high-temperature stage is 1000℃~1200℃.

[0018] As an improvement to the above technical solution, in the step of forming a temperature-regulating layer on the graphite disk substrate, the temperature-regulating layer is formed by radio frequency reactive magnetron sputtering, and the process parameters include: the target material is M1. v M2 w M3 x M4 y M5 z The sputtering gases were Ar and N2, with Ar flow rates of 40 sccm to 60 sccm and N2 flow rates of 30 sccm to 45 sccm. The RF power was 50 W to 80 W, the substrate bias was -120 V to -80 V, and the deposition gas pressure was 0.2 Pa to 1 Pa.

[0019] Accordingly, the present invention also discloses an MOCVD apparatus, which includes the graphite disk for MOCVD apparatus described above.

[0020] Implementing this invention has the following beneficial effects: In one embodiment of the present invention, a graphite disk for an MOCVD equipment includes a graphite disk substrate, a receiving groove, and a temperature-regulating layer. The temperature-regulating layer is disposed in a first region on the back side of the graphite disk substrate, and the first region is included in the orthographic projection region of the receiving groove on the back side; the radiation absorptivity of the temperature-regulating layer and the graphite disk substrate conforms to a specific relationship. Based on this, the temperature distribution of the graphite disk substrate can be effectively adjusted. Specifically, the difference between the radiation absorptivity of the graphite disk substrate and the radiation absorptivity of the temperature-regulating layer in the high-temperature stage is greater than the difference between the two in the low-temperature stage. This allows a larger temperature difference to be created on the surface of the graphite disk substrate in the high-temperature stage, thereby enabling the warped substrate to be heated at different temperatures, improving the temperature uniformity at different locations, and thus improving wavelength uniformity and yield. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the front structure of a graphite disk used in an MOCVD equipment according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the back side of a graphite disk used in an MOCVD equipment according to an embodiment of the present invention; Figure 3 This is a flowchart of a method for preparing a graphite disk for an MOCVD equipment according to an embodiment of the present invention; In the figure, 100 is the graphite disk substrate, 110 is the front side, 120 is the back side, 130 is the first area, 200 is the receiving groove, and 300 is the temperature regulating layer. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining this application and are not intended to limit this application.

[0023] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0026] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0027] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0028] Please see Figure 1 and Figure 2As a first aspect of the present invention, the present invention provides a graphite disk for an MOCVD apparatus, comprising a graphite disk substrate 100, a receiving groove 200, and a temperature regulating layer 300. The graphite disk substrate 100 has a front side 110 and a back side 120. The receiving groove 200 is disposed on the front side 110 of the graphite disk substrate 100 and is used to receive a substrate to be processed. The temperature regulating layer 300 is disposed in a first region 130 of the back side 120 of the graphite disk substrate 100, the first region 130 being included in the orthographic projection region of the receiving groove 200 on the back side 120. The temperature-regulating layer 300 and the graphite disk substrate 100 conform to the following relationship:

[0029] In the formula, The radiation absorptivity of the graphite disk substrate 100 at high temperatures. The radiation absorptivity of the temperature-regulating layer 300 at high temperatures. The radiation absorptivity of the graphite disk substrate 100 at low temperatures is given. The temperature-regulating layer 300 represents the radiation absorptivity at low temperatures (700℃~900℃) and at high temperatures (1000℃~1200℃). Since the graphite disk substrate 100 is primarily heated by infrared thermal radiation, introducing the temperature-regulating layer 300 on its back surface 120 effectively adjusts the temperature distribution of the graphite disk substrate. In this invention, the difference between the radiation absorptivity of the graphite disk substrate 100 at high temperatures and that of the temperature-regulating layer 300 is greater than the difference at low temperatures. This allows for a larger temperature difference to be created on the surface of the graphite disk substrate 100 at high temperatures, thereby enabling the warped substrate to be heated to varying degrees, improving temperature uniformity at different locations, and ultimately enhancing wavelength uniformity and yield.

[0030] Specifically, radiation absorptivity refers to the absorption rate of infrared radiation in the 800nm~1600nm band by the graphite disk substrate 100 / temperature-regulating layer 300. More specifically, radiation absorptivity = absorbed radiation amount / total incident radiation amount.

[0031] Specifically, the graphite disk substrate 100 is disk-shaped, and its front side 110 is provided with a plurality of receiving grooves 200 for loading the substrate to be processed. The cross-section of the receiving groove 200 (i.e., the cross-section perpendicular to the thickness direction of the graphite disk substrate 100) is circular. The receiving groove 200 is recessed into the graphite disk substrate 100 and has side walls and a bottom wall, the bottom wall of which is planar.

[0032] Specifically, the cross-section of the temperature-regulating layer 300 (i.e., the cross-section perpendicular to the thickness direction of the graphite disk substrate 100) can be circular, square, triangular, or hexagonal, but is not limited to these. Preferably, in some embodiments, the cross-section of the temperature-regulating layer 300 is circular, and the center of the orthographic projection of the temperature-regulating layer 300 on the back surface 120 coincides with the center of the orthographic projection of the receiving groove 200 on the back surface 120. Based on this, the temperature gradient can be better controlled, improving yield and wavelength uniformity.

[0033] Specifically, the temperature-regulating layer 300 may completely or partially cover the first region 130. Preferably, in some embodiments, the temperature-regulating layer 300 partially covers the first region 130. More specifically, the cross-section of the temperature-regulating layer 300 is circular, and the center of the orthographic projection of the temperature-regulating layer 300 on the back surface 120 coincides with the center of the orthographic projection of the receiving groove 200 on the back surface 120, and its diameter is smaller than the diameter of the receiving groove 200. Based on this, in the high-temperature stage, the thermal radiation absorption in the central region of the receiving groove 200 decreases, and the temperature in the central region decreases, thereby making the temperature distribution of the substrate to be processed in the receiving groove 200 more uniform and improving the yield. In the low-temperature stage, the difference between the radiation absorption rate of the temperature-regulating layer 300 and the radiation absorption rate of the graphite disk substrate 100 is small, and the thermal radiation energy decreases significantly after the temperature decreases. The combination of these two factors makes the temperature difference between the central region and the edge region of the receiving groove 200 very small, thereby also improving the temperature uniformity, wavelength uniformity, and yield.

[0034] More preferably, the diameter of the temperature-regulating layer 300 is 60% to 90% of the diameter of the receiving groove 200, exemplarily 64%, 68%, 72%, 76%, 80%, 84%, or 88%, but not limited thereto. More preferably, the diameter of the temperature-regulating layer 300 is 65% to 85% of the diameter of the receiving groove 200, and even more preferably 70% to 85%.

[0035] Specifically, the thickness of the temperature-regulating layer 300 is 20nm to 1000nm, and exemplary thicknesses are 50nm, 100nm, 150nm, 200nm, 350nm, 500nm, 650nm, 800nm, or 900nm, but not limited thereto. Preferably, the thickness of the temperature-regulating layer 300 is 50nm to 800nm.

[0036] Specifically, the thickness of the temperature-regulating layer 300 may be the same or different at various locations. Preferably, in some embodiments, the thickness of the temperature-regulating layer 300 decreases in a radial direction away from its center, that is, the thickness of the temperature-regulating layer 300 decreases from its center (center) towards its edge. Based on this, the temperature uniformity at various locations within the receiving tank 200 can be further improved, thereby improving wavelength uniformity and yield. Specifically, the decreasing change can be linear, stepwise, exponential, or polynomial, but is not limited to these.

[0037] Preferably, in some embodiments, the thickness of the temperature-regulating layer 300 at point i is determined according to the following formula:

[0038] Among them, T i The thickness of the temperature-regulating layer at point i is 300, r i Let R be the radius of the temperature-regulating layer 300 at radial position i, and T be the radius of the temperature-regulating layer 300. max denoted as the maximum thickness of the temperature-regulating layer 300 (i.e., the thickness at the center of the temperature-regulating layer 300), and n is a constant.

[0039] Among them, T max The value of is in the range of 20nm~1000nm, preferably 500nm~1000nm, and more preferably 600nm~900nm. The value of n is in the range of 0.5~2, preferably 0.8~1.5.

[0040] Specifically, the temperature-regulating layer 300 may be made of one or more materials such that its radiation absorptivity varies across different temperature ranges. Preferably, in some embodiments, the temperature-regulating layer 300 is made of (M1) v M2 w M3 x M4 y M5 z Made of N, M1, M2, M3, M4, and M5 are all selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, and Si, and each of M1, M2, M3, M4, and M5 is different, with v+w+x+y+z=1. This means that the temperature-regulating layer 300 is a high-entropy alloy layer, which not only allows for the adjustment of radiation absorption rate at different temperatures but also enhances the corrosion resistance of the material and extends the service life of the graphite disk.

[0041] More preferably, at least one of M1, M2, M3, M4, and M5 is Al, and the ratio of the atomic content of Al to the total atomic weight of M1, M2, M3, M4, and M5 is 5:100 to 20:100. Based on this, the temperature uniformity can be further improved.

[0042] More preferably, in some embodiments, M1 is Al, and the value of v ranges from 0.1 to 0.2; M2 is Cr, and the value of w ranges from 0.15 to 0.25; M3 is Ta, and the value of x ranges from 0.2 to 0.3; M4 is Ti, and the value of y ranges from 0.15 to 0.25; M5 is Zr, and the value of z ranges from 0.15 to 0.25. That is, the temperature-regulating coating is an AlCrTaTiZrN high-entropy alloy layer, which not only effectively improves temperature uniformity but also has high strength and corrosion resistance, further extending the service life of the graphite disk.

[0043] Accordingly, please refer to Figure 3 As a second aspect of the present invention, the present invention provides a method for preparing a graphite disk for an MOCVD device, comprising the following steps: S1: Provides the graphite disk substrate; S2: A temperature-regulating layer is formed on the graphite disk substrate; The graphite disk substrate has a front side and a back side. A receiving groove is located on the front side of the graphite disk substrate and is used to receive the substrate to be processed. A temperature regulating layer is located in a first region on the back side of the graphite disk substrate. The first region is included in the orthographic projection region of the receiving groove on the back side. The temperature-regulating layer and the graphite disk substrate conform to the following relationship:

[0044] In the formula, The radiation absorptivity of the graphite disk substrate at high temperatures. The radiation absorptivity of the temperature-regulating layer during high-temperature stages. The radiation absorptivity of the graphite disk substrate at low temperatures. The temperature-regulating layer represents the radiation absorptivity at low temperatures (700℃~900℃) and at high temperatures (1000℃~1200℃). Since the graphite disk substrate is primarily heated by infrared thermal radiation, introducing a temperature-regulating layer on its back side effectively adjusts the temperature distribution of the graphite disk substrate. In this invention, the difference between the radiation absorptivity of the graphite disk substrate at high temperatures and that of the temperature-regulating layer is greater than the difference at low temperatures. This allows for a larger temperature difference to be created on the surface of the graphite disk substrate at high temperatures, enabling the warped substrate to be heated at different temperatures, improving temperature uniformity at different locations, and consequently improving wavelength uniformity and yield.

[0045] Specifically, in step S1, a basic protective coating such as SiC may be provided on the surface of the graphite disk substrate, but it is not limited to this. Preferably, in some embodiments, the MOCVD graphite disk is cleaned, specifically, using deionized water, acetone, etc., and then dried to ensure that there are no residual solvents or impurities on the surface.

[0046] Specifically, in step S2, a temperature-regulating layer can be formed by vapor deposition. Preferably, in some embodiments, the temperature-regulating layer is formed by radio frequency reactive magnetron sputtering, the process parameters of which include: the target material is M1. v M2 w M3 x M4 y M5 z(It can be prepared by hot extrusion sintering process), the sputtering gas is Ar and N2, the flow rate of Ar is 40sccm~60sccm, the flow rate of N2 is 30sccm~45sccm, the RF power is 50W~80W, the substrate bias is -120V~-80V, and the deposition gas pressure is 0.2Pa~1Pa.

[0047] Preferably, in some embodiments, in order to form a temperature-controlled layer with a specific thickness distribution, a photolithography etching process can be used after deposition, and gradient exposure can be controlled to form different thickness distributions. Alternatively, a rotating mask can be introduced during the masking process, and the thickness of the temperature-controlled layer can be adjusted by controlling the position, aperture size, and aperture time of the mask.

[0048] Preferably, in some embodiments, after the temperature-regulating layer is formed, it is annealed under an inert atmosphere or vacuum conditions at a temperature of 700°C to 900°C for a time of 0.5h to 4h. Annealing can improve the crystal quality of the temperature-regulating layer.

[0049] As a third aspect of the present invention, the present invention provides an MOCVD apparatus, which includes the graphite disk for MOCVD apparatus described above, wherein a temperature regulating layer is disposed in a first region on the back side of the graphite disk, and the first region is included in the orthographic projection region of the receiving groove on the back side. The temperature-regulating layer and the graphite disk substrate conform to the following relationship:

[0050] In the formula, The radiation absorptivity of the graphite disk substrate at high temperatures. The radiation absorptivity of the temperature-regulating layer during high-temperature stages. The radiation absorptivity of the graphite disk substrate at low temperatures. The temperature-regulating layer represents the radiation absorptivity at low temperatures (700℃~900℃) and at high temperatures (1000℃~1200℃). Since the graphite disk substrate is primarily heated by infrared thermal radiation, introducing a temperature-regulating layer on its back side effectively adjusts the temperature distribution of the graphite disk substrate. In this invention, the difference between the radiation absorptivity of the graphite disk substrate at high temperatures and that of the temperature-regulating layer is greater than the difference at low temperatures. This allows for a larger temperature difference to be created on the surface of the graphite disk substrate at high temperatures, enabling the warped substrate to be heated at different temperatures, improving temperature uniformity at different locations, and consequently improving wavelength uniformity and yield.

[0051] The present invention will be further described below with reference to specific embodiments: Example 1 This embodiment provides a graphite disk for an MOCVD equipment, comprising a graphite disk substrate, a receiving groove, and a temperature-regulating layer. The graphite disk substrate has a front and a back side, and the receiving groove is located on the front side of the graphite disk substrate, used to receive the substrate to be processed. The bottom wall of the receiving groove is planar.

[0052] The temperature-regulating layer is disposed in a first region on the back side of the graphite disk substrate, and the first region is included in the orthographic projection region of the receiving groove on the back side; the temperature-regulating layer is (Al) 0.15 Cr 0.20 Ta 0.25 Ti 0.20 Zr 0.20 The N-layer has a higher radiation absorptivity at low temperatures than at high temperatures.

[0053] The temperature-regulating layer has a circular cross-section. The center of the temperature-regulating layer's orthographic projection on the back coincides with the center of the receiving groove's orthographic projection on the back, and its diameter is 80% of the diameter of the receiving groove.

[0054] The thickness of the temperature-regulating layer at point i is determined by the following formula:

[0055] Among them, T i Let r be the thickness of the temperature-regulating layer at point i. i Let R be the radius of the temperature-regulating layer at radial position i, and T be the radius of the temperature-regulating layer. max The maximum thickness of the temperature-regulating layer is 600 nm, and n is a constant, which is 1.2.

[0056] The method for preparing the graphite disk for the MOCVD equipment in this embodiment is as follows: (1) Provide a graphite disk substrate, and ultrasonically clean it in acetone and anhydrous ethanol for 30 minutes each. After drying with nitrogen, load it into the reaction chamber and evacuate it to 5.0 × 10⁻⁶. -3 Pa; (2) A temperature-controlled layer is formed by radio frequency reactive magnetron sputtering, the process parameters of which include: the target material is Al 0.15 Cr 0.20 Ta 0.25 Ti 0.20 Zr 0.20 The sputtering gases were Ar and N2, with an Ar flow rate of 50 sccm and an N2 flow rate of 30 sccm. The RF power was 70 W, the substrate bias was -100 V, and the deposition gas pressure was 0.5 Pa.

[0057] (3) Anneal at 700°C for 2 hours under vacuum conditions.

[0058] Example 2 This embodiment provides a graphite disk for an MOCVD equipment, comprising a graphite disk substrate, a receiving groove, and a temperature-regulating layer. The graphite disk substrate has a front and a back side, and the receiving groove is located on the front side of the graphite disk substrate, used to receive the substrate to be processed; the bottom wall of the receiving groove is planar.

[0059] The temperature-regulating layer is disposed in a first region on the back side of the graphite disk substrate, and the first region is included in the orthographic projection region of the receiving groove on the back side; the temperature-regulating layer is (Hf 0.22 Nb 0.18 Ta 0.22 Ti 0.19 Zr 0.19 The N-layer has a higher radiation absorptivity at low temperatures than at high temperatures.

[0060] The temperature-regulating layer has a circular cross-section. The center of the temperature-regulating layer's orthographic projection on the back coincides with the center of the receiving groove's orthographic projection on the back, and its diameter is 80% of the diameter of the receiving groove.

[0061] The thickness of the temperature-regulating layer at point i is determined by the following formula:

[0062] Among them, T i Let r be the thickness of the temperature-regulating layer at point i. i Let R be the radius of the temperature-regulating layer at radial position i, and T be the radius of the temperature-regulating layer. max The maximum thickness of the temperature-regulating layer is 800 nm, and n is a constant, which is 1.

[0063] The method for preparing the graphite disk for the MOCVD equipment in this embodiment is as follows: (1) Provide a graphite disk substrate, and ultrasonically clean it in acetone and anhydrous ethanol for 30 minutes each. After drying with nitrogen, load it into the reaction chamber and evacuate it to 5.0 × 10⁻⁶. -3 Pa; (2) A temperature-controlled layer is formed by radio frequency reactive magnetron sputtering, the process parameters of which include: the target material is Hf 0.22 Nb 0.18 Ta 0.22 Ti 0.19 Zr 0.19 The sputtering gases were Ar and N2, with an Ar flow rate of 40 sccm and an N2 flow rate of 40 sccm. The RF power was 60 W, the substrate bias was -120 V, and the deposition pressure was 0.6 Pa.

[0064] (3) Anneal at 750°C for 3 hours under vacuum conditions.

[0065] Comparative Example 1 This comparative example provides a graphite disk for an MOCVD device, which differs from Example 1 in that: No temperature-regulating layer is formed; otherwise, it is the same as in Example 1.

[0066] Comparative Example 2 This comparative example provides a graphite disk for an MOCVD device, which differs from Example 1 in that: No temperature regulating layer is formed, and the bottom of the receiving tank is slightly concave arc-shaped.

[0067] Everything else is the same as in Example 1.

[0068] The graphite disks from Examples 1, 2, Comparative Example 1, and 2 were used for green LED epitaxial (InGaN-GaN based) deposition, and the wavelength was measured and wavelength uniformity was calculated. The yield was statistically analyzed, and the specific data are shown in the table below:

[0069] As can be seen from the table, the wavelength uniformity and yield of LEDs are effectively improved after adopting the technical solution of the present invention. A comparison between Comparative Example 1 and Example 1 shows that when a flat-bottomed receiving tank is used and the temperature-regulating layer of the present invention is not provided, although the yield is relatively high, the wavelength uniformity is poor. A comparison between Comparative Example 2 and Example 1 shows that when a slightly concave arc-shaped receiving tank is used but the temperature-regulating layer of the present invention is not provided, although the wavelength uniformity is relatively good, the yield decreases.

[0070] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with the described embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0071] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A graphite disk for an MOCVD equipment, characterized in that, include: A graphite disk substrate having a front and a back side; Multiple receiving slots are provided on the front side of the graphite disk substrate; A temperature-regulating layer is disposed in a first region on the back side of the graphite disk substrate, the first region being included in the orthographic projection region of the receiving groove on the back side; The temperature-regulating layer and the graphite disk substrate conform to the following relationship: in, The radiation absorptivity of the graphite disk substrate at high temperatures. The radiation absorptivity of the temperature-regulating layer during high-temperature stages. The radiation absorptivity of the graphite disk substrate at low temperatures. The radiation absorptivity of the temperature-regulating layer at low temperatures; The temperature range of the low-temperature stage is 700℃~900℃, and the temperature range of the high-temperature stage is 1000℃~1200℃.

2. The graphite disk for MOCVD equipment as described in claim 1, characterized in that, The temperature regulating layer has a circular cross-section, and the center of the temperature regulating layer's orthographic projection on the back side coincides with the center of the receiving groove's orthographic projection on the back side. The diameter of the temperature-regulating layer is smaller than the diameter of the receiving tank.

3. The graphite disk for MOCVD equipment as described in claim 2, characterized in that, The thickness of the temperature-regulating layer decreases in a radial direction away from its center.

4. The graphite disk for MOCVD equipment as described in claim 2, characterized in that, The diameter of the temperature-regulating layer is 60% to 90% of the diameter of the receiving groove.

5. The graphite disk for MOCVD equipment as described in claim 2, characterized in that, The thickness of the temperature-regulating layer at point i is determined according to the following formula: Among them, T i Let r be the thickness of the temperature-regulating layer at point i. i Let R be the radius of the temperature-regulating layer at radial position i, and T be the radius of the temperature-regulating layer. max Where n is the maximum thickness of the temperature-regulating layer; T max The value of is in the range of 20nm to 1000nm, and the value of n is in the range of 0.5 to 2.

6. The graphite disk for MOCVD equipment as described in claim 1, characterized in that, The temperature regulating layer is composed of (M1) v M2 w M3 x M4 y M5 z Made of N, M1, M2, M3, M4, and M5 are all selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, and Si, and M1, M2, M3, M4, and M5 are all different; v+w+x+y+z=1.

7. The graphite disk for MOCVD equipment as described in claim 6, characterized in that, M1 is Al, and the value of v ranges from 0.1 to 0.2; M2 is Cr, and the value of w ranges from 0.15 to 0.25; M3 is Ta, and the value of x ranges from 0.2 to 0.3; M4 represents Ti, and the value of y ranges from 0.15 to 0.25; M5 is Zr, and the value of z ranges from 0.15 to 0.

25.

8. A method for preparing a graphite disk for an MOCVD device, comprising preparing a graphite disk for an MOCVD device as described in any one of claims 1 to 7, characterized in that, include: Provide graphite disk substrate; The graphite disk substrate has a front and a back, and the front has multiple receiving grooves; A temperature-regulating layer is formed on the graphite disk substrate; The temperature-regulating layer is disposed in a first region on the back side of the graphite disk substrate, and the first region is included in the orthographic projection region of the receiving groove on the back side; the temperature-regulating layer and the graphite disk substrate conform to the following relationship: in, The radiation absorptivity of the graphite disk substrate at high temperatures. The radiation absorptivity of the temperature-regulating layer during high-temperature stages. The radiation absorptivity of the graphite disk substrate at low temperatures. The radiation absorptivity of the temperature-regulating layer at low temperatures; The temperature range of the low-temperature stage is 700℃~900℃, and the temperature range of the high-temperature stage is 1000℃~1200℃.

9. The method for preparing a graphite disk for an MOCVD device as described in claim 8, characterized in that, In the step of forming a temperature-controlled layer on the graphite disk substrate, the temperature-controlled layer is formed by radio frequency reactive magnetron sputtering, and the process parameters include: the target material is M1. v M2 w M3 x M4 y M5 z The sputtering gases were Ar and N2, with Ar flow rates of 40 sccm to 60 sccm and N2 flow rates of 30 sccm to 45 sccm. The RF power was 50 W to 80 W, the substrate bias was -120 V to -80 V, and the deposition gas pressure was 0.2 Pa to 1 Pa.

10. An MOCVD apparatus, characterized in that, Includes the graphite disk for MOCVD equipment as described in any one of claims 1 to 7.

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