Preparation method of high-consistency patterned substrate, patterned substrate and LED epitaxial wafer

Abstract

The embodiment of the invention provides a preparation method of a high-consistency patterned substrate, the patterned substrate and an LED epitaxial wafer. The method comprises the following steps: firstly, providing a substrate; at least one of physical, chemical or mechanical planarization technologies is applied to carry out atomic-scale planarization processing on the first surface of the substrate so that the roughness of the first surface reaches the first surface roughness range, and / or atomic-scale planarization processing is carried out on the second surface of the substrate so that the roughness of the second surface reaches the first surface roughness range; the roughness of the second surface reaches the second surface roughness range; forming a photoresist layer on the second surface of the substrate; and exposing the photoresist layer by using a mask so as to transfer the pattern on the mask to the second surface of the substrate. The problem that the uniformity of the etched patterned substrate is reduced due to the fact that exposure light beams are reflected and refracted on the surface of the substrate when penetrating through the substrate in the exposure process of the patterning process due to the rough surface of the substrate is solved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the fields of semiconductor manufacturing and microelectronics technology, and in particular to a method for preparing a highly consistent patterned substrate, a patterned substrate and an LED epitaxial wafer. Background Art

[0002] In the manufacturing process of semiconductor and optoelectronic devices, the microstructure of the substrate surface has a direct impact on the performance of the device. With the continuous technological development and update of the semiconductor industry, the size of the pattern is constantly reduced, and the requirements for the quality of epitaxial growth are getting higher and higher, so the consistency of the pattern in the substrate is becoming more and more important.

[0003] The microstructure of the existing patterned substrate can improve the epitaxy quality and enhance the luminous efficiency to a certain extent. However, as the pattern size becomes smaller and smaller, the parameter performance of the flat substrate itself also affects the stability of the patterning process to a certain extent, resulting in uneven patterning and affecting the reliability and performance of the device. In particular, the surface roughness of the substrate causes the light to be refracted from the back to expose the photoresist multiple times during the patterning process exposure process due to the reasons of front roughness and back roughness. This affects the consistency and stability of the yellow light resist column during the patterning process, and further reduces the uniformity of the patterned substrate after etching. Summary of the invention

[0004] The present invention provides a method for preparing a highly consistent patterned substrate, a patterned substrate and an LED epitaxial wafer, wherein a substrate surface is planarized to reduce the refraction of exposure light caused by the roughness of the substrate surface during exposure, which may cause multiple exposures of the photoresist and affect the consistency of the yellow photoresist column, thereby reducing the consistency of the patterned substrate after etching.

[0005] In a first aspect, an embodiment of the present invention provides a method for preparing a highly consistent patterned substrate, comprising:

[0006] providing a substrate;

[0007] Apply at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or perform atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range; wherein the second surface is a surface to be etched, and the first surface and the second surface are opposite to each other in the thickness direction of the substrate;

[0008] forming a photoresist layer on the second surface of the substrate;

[0009] The photoresist layer is exposed using a mask to transfer the pattern on the mask to the second surface of the substrate.

[0010] Optionally, applying at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or performing atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range, comprises:

[0011] Using mechanical polishing technology to mechanically polish the first surface and the second surface of the sapphire single crystal;

[0012] The chemical mechanical polishing technology is applied to planarize the first surface and the second surface of the sapphire single crystal so that the roughness of the first surface reaches a first surface roughness range, and the roughness of the second surface reaches a second surface roughness range.

[0013] Optionally, a substrate is provided, comprising:

[0014] Provide a 6-inch sapphire single crystal substrate with a diameter of 150 mm;

[0015] Applying mechanical polishing technology to mechanically polish the first surface and the second surface of the sapphire single crystal includes:

[0016] The first surface and the second surface of the sapphire single crystal are mechanically polished using a diamond suspension with a particle size of 1 μm as an abrasive; wherein the grinding pressure of the mechanical polishing is 2-3 N / cm 2 , the grinding speed is 50rpm-80rpm, and the grinding time is 1-2 hours;

[0017] Applying chemical mechanical polishing technology to planarize the first surface and the second surface of the sapphire single crystal includes:

[0018] The first surface and the second surface of the sapphire single crystal are planarized by applying chemical mechanical polishing technology; wherein the chemical solution of the chemical mechanical polishing is a mixture of potassium hydroxide and deionized water in a ratio of 1:10, the abrasive particles are silicon dioxide with an average particle size of 0.05 μm-1 μm, the polishing speed is 100 rpm-120 rpm, and the polishing pressure is 1-5 N / cm 2 , polishing time is 30-60 minutes.

[0019] Optionally, applying at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or performing atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range, comprises:

[0020] Apply at least two of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range;

[0021] Apply one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range.

[0022] Optionally, the first surface roughness ranges from 0.01 μm to 1 μm.

[0023] Optionally, the second surface roughness ranges from 0 nm to 0.1 nm.

[0024] Optionally, the physical planarization technology includes one or more of physical vapor deposition, physical etching, ion beam polishing, and magnetron sputtering; the chemical planarization technology includes one or more of wet etching, chemical etching, chemical vapor deposition, and chemical mechanical polishing; the mechanical planarization technology includes precision grinding and polishing processes.

[0025] Optionally, the pressure parameter of the chemical mechanical polishing is 1-5N / cm 2 , the rotation speed is 60-100rpm, and the polishing time is 0.5-2 hours; the chemical solution used in the chemical mechanical polishing is a mixture of potassium hydroxide and deionized water in a ratio of 1:10, and the abrasive particles are silicon dioxide with an average particle size of 0.05μm-1μm.

[0026] In a second aspect, an embodiment of the present invention further provides a patterned substrate, which is prepared by the method for preparing a highly consistent patterned substrate as described in any one of the first aspects of the present invention.

[0027] In a third aspect, an embodiment of the present invention further provides an LED epitaxial wafer, comprising the patterned substrate as described in the second aspect of the present invention.

[0028] An embodiment of the present invention provides a method for preparing a highly consistent patterned substrate, a patterned substrate and an LED epitaxial wafer. The method first provides a substrate; applies at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or performs atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range; wherein the second surface is a surface to be etched, and the first surface and the second surface deviate from each other in the thickness direction of the substrate; forms a photoresist layer on the second surface of the substrate; and uses a mask to expose the photoresist layer to transfer the pattern on the mask to the second surface of the substrate. The above technical solution solves the problem that due to the rough surface of the substrate, during the patterning process exposure, the exposure light beam will be refracted and reflected on the substrate surface when passing through the substrate, which will expose the photoresist multiple times, thereby affecting the consistency and stability of the photoresist column in the patterning process, and further resulting in a decrease in the uniformity of the patterned substrate after etching; by flattening the substrate surface, the uniformity and consistency of the photoresist column can be improved, thereby improving the uniformity and consistency of the patterned substrate, and improving the reliability and performance of the final device. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic flow chart of a method for preparing a highly consistent patterned substrate provided by an embodiment of the present invention;

[0030] Figure 2 It is a schematic diagram of a photoresist column structure on a substrate that has not been planarized, provided by an embodiment of the present invention;

[0031] Figure 3 It is a schematic diagram of a photoresist column structure on a flattened substrate provided by an embodiment of the present invention;

[0032] Figure 4 It is a schematic diagram showing the influence of a planarized substrate provided by an embodiment of the present invention on the concentration of yellow light reflectivity after being applied to a patterning process;

[0033] Figure 5 It is a schematic flow chart of another method for preparing a highly consistent patterned substrate provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0035] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. It should be noted that the directional words such as "upper", "lower", "left", "right" and the like described in the embodiments of the present invention are described at the angles shown in the accompanying drawings and should not be understood as limitations on the embodiments of the present invention. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is formed "on" or "under" another element, it can not only be directly formed "on" or "under" another element, but also indirectly formed "on" or "under" another element through an intermediate element. The terms "first", "second", etc. are only used for descriptive purposes and do not represent any order, quantity or importance, but are only used to distinguish different components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific circumstances.

[0036] The term “including” and its variations used in the present invention are open inclusions, that is, “including but not limited to.” The term “based on” means “based at least in part on.” The term “one embodiment” means “at least one embodiment.”

[0037] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish the corresponding contents, and are not used to limit the order or interdependence.

[0038] It should be noted that the modifications of "one" and "plurality" mentioned in the present invention are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0039] Figure 1 is a schematic diagram of a process for preparing a highly consistent patterned substrate provided by an embodiment of the present invention, with reference to Figure 1 , the method comprising:

[0040] S110, providing a substrate.

[0041] Illustratively, the material of the substrate may be a sapphire wafer, a silicon wafer, a silicon carbide wafer, an aluminum nitride wafer, a gallium nitride wafer, diamond, etc., but the present invention is not limited thereto.

[0042] S120. Apply at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or perform atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range; wherein the second surface is a surface to be etched, and the first surface and the second surface deviate from each other in the thickness direction of the substrate.

[0043] Specifically, a photoresist layer is formed on a substrate, and then the photoresist layer is patterned using a photolithography exposure technique. Specifically, under the action of light, the pattern on the mask is transferred to the substrate with the help of a photoresist, and then the desired photoresist column, i.e., the mask pattern, is formed on the second surface of the substrate, i.e., the surface to be etched, through a development process. Then, based on the mask pattern, other etching processes such as dry etching or wet etching are used to pattern the surface to be etched of the substrate, and a plurality of basic raised microstructures are formed on the substrate to obtain a patterned substrate. In this process, when the photoresist layer is exposed to form photoresist columns, the exposure light beam is emitted from top to bottom to the photoresist layer. Due to the rough surface of the substrate, reflection and refraction will occur on the front side, i.e., the second surface, and the back side, i.e., the first surface of the substrate, thereby causing secondary exposure to the photoresist column, which in turn causes problems such as uneven morphology, non-concentrated size, and poor uniformity of the photoresist column. The reflectivity of light is related to the surface roughness. Therefore, controlling the roughness of the substrate surface can reduce reflection and refraction, and solve the problem of secondary exposure of the photoresist column by the exposure light. Therefore, at least one of the physical, chemical or mechanical planarization techniques is used to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches the first surface roughness range, and / or the second surface of the substrate is atomic-level planarized so that the roughness of the second surface reaches the second surface roughness range; illustratively, the first surface roughness range is 0.01μm-1μm, and the second surface roughness range is 0nm-0.1nm. That is, the back and front of the substrate are atomically planarized so that the roughness of the front of the substrate is close to 0nm, so that all the exposure light is directly incident on the inside of the substrate, and the back roughness is between 0.01μm-1μm, which will not cause the back roughness to be too low, and the incident light basically penetrates the substrate, and is absorbed too little by the substrate, thereby reducing the exposure efficiency.

[0044] In an optional embodiment of the present invention, after any surface of the substrate is planarized, the surface roughness of the substrate is detected using an atomic force microscope (AFM). After determining that it reaches the roughness range, the surface reflectivity of the substrate is detected using an automatic optical detection system. If it still does not meet the required optical indicators, the other surface is flattened at the atomic level.

[0045] Figure 2 is a schematic diagram of a photoresist column structure on a substrate that has not been planarized, provided in an embodiment of the present invention. Figure 3 is a schematic diagram of a photoresist column structure on a substrate subjected to a planarization treatment according to an embodiment of the present invention, with reference to Figure 2 , Figure 3, the bottom diameter of the glue column is significantly smaller for the substrate that has not been flattened, while the bottom diameter of the glue column is significantly larger for the substrate that has been flattened. That is, for the substrate that has not been flattened, the light passing through the back of the substrate is affected by the roughness, and when it refracts out of the front of the substrate, it is not parallel to the incident light, and acts on the bottom of the photoresist layer, causing a secondary exposure effect, which leads to a reduction in the size of the bottom of the glue column after development. For the substrate that has been flattened, the surface of the substrate reaches the atomic level, reducing the reflection of light and the subsequent multiple exposure of the photoresist; at the same time, the air gap between the substrate with greater roughness and the wafer stage is enlarged, which still promotes the reflection of light and affects the exposure uniformity.

[0046] In order to further verify the effect of the flat sheet planarization treatment on the reflectivity (mean value) of the yellow light glue column in the subsequent PSS process, a batch of 6-inch substrates after planarization treatment and a batch of 6-inch substrates without planarization treatment were fed separately. Figure 4 Schematic diagram of the effect of a planarized substrate provided by an embodiment of the present invention on the concentration of yellow light reflectivity after being applied to a patterning process. Figure 4 After the flat sheet was flattened, the concentration of PSS yellow light reflectivity was significantly improved, and the mean value of reflectivity in the yellow light process was increased from 74.9% to 86.6%, which effectively improved the yellow light yield of the PSS process, not only reducing the difficulty of process control, but also reducing the number of reworked sheets and reducing costs.

[0047] S130, forming a photoresist layer on the second surface of the substrate.

[0048] Specifically, after the first surface and / or the second surface of the substrate is planarized, a patterning process is performed on the surface to ensure high consistency, so that a photoresist layer can be formed on the second surface of the substrate, i.e., the upper surface, so that the photoresist layer can be subsequently exposed to form uniform photoresist columns.

[0049] The method for forming the photoresist layer is not limited in the embodiment of the present invention, and those skilled in the art may select the method according to actual needs, for example, by coating, etc., but not limited thereto.

[0050] S140, exposing the photoresist layer using a mask to transfer the pattern on the mask to the second surface of the substrate.

[0051] Exemplarily, a photoresist layer is exposed using a mask in a photolithography machine, and then a photoresist column corresponding to the desired mask pattern can be obtained on the surface to be etched, i.e., the front side of the substrate through a development process. At this time, since the substrate surface has been planarized, the uniformity and consistency of the obtained photoresist column are greatly improved. Among them, the specific implementation method of the development process is not limited by the embodiment of the present invention, and those skilled in the art can set it according to actual needs. For example, a developer can be used to dissolve the photoresist in the exposure area of ​​the positive photoresist and the non-exposure area of ​​the negative photoresist to obtain a photoresist column, but it is not limited to the above method.

[0052] A method for preparing a highly consistent patterned substrate provided by an embodiment of the present invention comprises the following steps: firstly providing a substrate, then applying at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on a first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or performing atomic-level planarization on a second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range; forming a photoresist layer on the second surface of the substrate, and finally exposing the photoresist layer using a mask to transfer the pattern on the mask to the second surface of the substrate; the above-mentioned technical method The solution solves the problem that due to the rough surface of the substrate, the exposure beam will be refracted and reflected on the substrate surface when passing through the substrate during the patterning process exposure, which will expose the photoresist multiple times, thereby affecting the consistency and stability of the photoresist column in the patterning process, and further resulting in a decrease in the uniformity of the patterned substrate after etching; by flattening the substrate surface, the uniformity and consistency of the photoresist column can be improved, thereby improving the uniformity and consistency of the patterned substrate, ensuring the growth effect of the epitaxial layer on the patterned substrate, and improving the reliability and performance of the final device.

[0053] It should be noted that physical planarization technology includes one or more of physical vapor deposition, physical etching, ion beam polishing, and magnetron sputtering; chemical planarization technology includes one or more of wet etching, chemical etching, chemical vapor deposition, and chemical mechanical polishing; mechanical planarization technology includes precision grinding and polishing processes.

[0054] It is understandable that the back side of the substrate substrate that has not been planarized, i.e., the first surface, is a rough structure, and the back side of the substrate substrate is in contact with the photolithography stage; at this time, when the light penetrates the back side of the substrate, it may be reflected at the gap between the substrate substrate and the photolithography stage. Therefore, after the back side of the substrate substrate, i.e., the first surface, is planarized at the atomic level, the substrate substrate and the photolithography stage will be closely attached to prevent the light beam from being reflected at the gap between the substrate substrate and the photolithography stage.

[0055] In an optional embodiment of the present invention, only one planarization technology can be used to planarize the first surface and the second surface of the substrate. In this case, the planarization time can be controlled so that the two surfaces meet their respective roughness ranges; different combinations of planarization technologies can also be selected to meet their respective roughness ranges; the present invention is not limited to this.

[0056] For example, if chemical planarization technology is selected to planarize the first surface and the second surface of the substrate, the polishing liquid includes but is not limited to SiO2, AL2O3, TiO2, MgO, iron oxide, etc.; different chemical solutions can be selected to treat the front and back sides of the substrate to achieve different atomic-level planarization effects.

[0057] For example, if a physical planarization technology is selected to planarize the first surface and the second surface of the substrate, different polishing pressures and speeds may be selected according to different planarization requirements of the two surfaces to achieve different atomic-level planarization effects.

[0058] In an optional embodiment of the present invention, the above step S120, applying at least one of physical, chemical or mechanical planarization technology to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or performing atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range, includes:

[0059] The mechanical polishing technology is applied to mechanically polish the first surface and the second surface of the substrate.

[0060] Specifically, since the defects on the surface of the substrate include relatively large macroscopic defects and relatively small microscopic defects, a mechanical polishing technique is firstly used to mechanically polish the first surface and the second surface of the substrate to remove the macroscopic defects.

[0061] For example, a diamond suspension with a particle size of 1 μm can be used as an abrasive, and a precision mechanical polishing machine equipped with a dedicated sapphire polishing pad can be used to mechanically polish the first surface and the second surface of the sapphire single crystal; wherein the grinding pressure of the mechanical polishing is 2-3 N / cm 2 , the grinding speed is 50rpm-80rpm, and the grinding time is 1-2 hours.

[0062] The chemical mechanical polishing technology is applied to planarize the first surface and the second surface of the substrate so that the roughness of the first surface reaches the first surface roughness range and the roughness of the second surface reaches the second surface roughness range.

[0063] Specifically, after removing the macro defects, in order to further ensure the atomic-level flattening effect, the chemical mechanical polishing technology is used to further flatten the first surface and the second surface of the substrate; illustratively, the chemical solution of the chemical mechanical polishing is a mixture of potassium hydroxide and deionized water in a ratio of 1:10, the abrasive particles are silicon dioxide with an average particle size of 0.05 μm-1 μm, the polishing speed is 100 rpm-120 rpm, and the polishing pressure is 1-5 N / cm 2 , the polishing time is 30-60 minutes. It should be noted that, since the roughness requirements of the first surface and the second surface are different, the polishing time can also be different during polishing; for example, the first surface can be polished for 30 minutes, and the second surface, i.e., the front surface, has a higher roughness requirement, and can be polished for 50 minutes to achieve a better flattening effect.

[0064] Figure 5 is a schematic diagram of a process for preparing another method for a highly consistent patterned substrate provided by an embodiment of the present invention, with reference to Figure 5 , the preparation method of the embodiment of the present invention comprises the following steps:

[0065] S210, providing a substrate.

[0066] S220, applying at least two of physical, chemical or mechanical planarization techniques to perform atomic-level planarization processing on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range.

[0067] Specifically, when the substrate is subsequently coated with glue and exposed and developed, the exposure light beam goes from top to bottom, that is, the light beam will first reach the front surface of the substrate, that is, the second surface. In order to make the light pass through the front surface of the substrate as directly as possible and reduce reflection and refraction, the second surface of the substrate needs to be as flat as possible. Therefore, at least two of the physical, chemical or mechanical flattening technologies can be applied to perform atomic-level flattening treatment on the second surface of the substrate so that the roughness of the second surface reaches the second surface roughness range, that is, the second surface of the substrate reaches a higher degree of flattening; therefore, the use of at least two flattening technologies can ensure a better flattening effect while further improving the flattening efficiency of the front side of the substrate.

[0068] S230, applying one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization processing on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range.

[0069] Specifically, when the substrate is exposed, the exposure light is incident from the front surface (second surface) of the substrate, passes through the substrate to the back surface, that is, the first surface, and the back surface is relatively rough, which will cause the exposure light beam to be reflected, refracted, and diffracted, thereby possibly causing secondary exposure. Therefore, it is also necessary to control the roughness of the back side; that is, the first surface of the substrate is atomically flattened so that the roughness of the first surface reaches the roughness range of the first surface; at the same time, if the roughness of the back side is too low, most of the exposure light incident on the substrate will pass through the back side of the substrate, thereby reducing the exposure efficiency; therefore, the requirement for the roughness of the back side is relatively low, and illustratively, it can be 0.3μm-0.4μm; at this time, one of the physical, chemical or mechanical flattening techniques can be applied to perform atomic-level flattening on the first surface of the substrate; compared with the front side of the substrate with a higher degree of flattening, the back side only requires one flattening process to meet the flattening requirements, which can reduce costs.

[0070] S240, forming a photoresist layer on the second surface of the substrate.

[0071] S250, exposing the photoresist layer using a mask to transfer the pattern on the mask to the second surface of the substrate.

[0072] The specific implementation method of the above steps is the same as that in the above embodiment and will not be repeated here.

[0073] The technical solution of the embodiment of the present invention performs atomic-level flattening treatment on the second surface of the substrate by applying at least two of physical, chemical or mechanical flattening technologies so that the roughness of the second surface reaches the second surface roughness range; and performs atomic-level flattening treatment on the first surface of the substrate by applying one of physical, chemical or mechanical flattening technologies so that the roughness of the first surface reaches the first surface roughness range; while meeting the flattening requirements of the first and second surfaces of the substrate, the flattening efficiency is improved and the cost is controlled.

[0074] Based on the same inventive concept, an embodiment of the present invention further provides a patterned substrate, which is prepared using the method for preparing a highly consistent patterned substrate provided by any embodiment of the present invention; the patterned substrate includes a substrate and a patterned microstructure located on the substrate.

[0075] Since the method for preparing a highly consistent patterned substrate provided by an embodiment of the present invention can improve the uniformity and consistency of the photoresist column, the patterned substrate prepared based on the method can effectively improve the range and uniformity of the pattern microstructure on the substrate, improve the concentration and hit rate of the product, and thus improve the success rate and stability of the subsequent process. The patterned substrate provided by an embodiment of the present invention includes all the technical features and corresponding beneficial effects of the method for preparing a highly consistent patterned substrate provided by any embodiment of the present invention, which will not be repeated here.

[0076] The embodiment of the present invention further provides an LED epitaxial wafer. Since the LED epitaxial wafer includes the patterned substrate in the above embodiment, it has the corresponding beneficial effects of the patterned substrate provided by the embodiment of the present invention, which will not be described in detail here.

[0077] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for preparing a highly consistent patterned substrate, It is characterized in that include: providing a substrate; Apply at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or perform atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range; wherein the second surface is a surface to be etched, and the first surface and the second surface are opposite to each other in the thickness direction of the substrate; forming a photoresist layer on the second surface of the substrate; The photoresist layer is exposed using a mask to transfer the pattern on the mask to the second surface of the substrate.

2. The preparation method according to claim 1, It is characterized in that Applying at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or performing atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range, comprising: Applying mechanical polishing technology to mechanically polish the first surface and the second surface of the substrate; The first surface and the second surface of the substrate are planarized by applying chemical mechanical polishing technology, so that the roughness of the first surface reaches a first surface roughness range, and the roughness of the second surface reaches a second surface roughness range.

3. The preparation method according to claim 2, It is characterized in that A substrate is provided, comprising: Provide a 6-inch sapphire single crystal substrate with a diameter of 150 mm; Applying mechanical polishing technology to mechanically polish the first surface and the second surface of the sapphire single crystal includes: The first surface and the second surface of the sapphire single crystal are mechanically polished using a diamond suspension with a particle size of 1 μm as an abrasive; wherein the grinding pressure of the mechanical polishing is 2-3 N / cm 2 , the grinding speed is 50rpm-80rpm, and the grinding time is 1-2 hours; Applying chemical mechanical polishing technology to planarize the first surface and the second surface of the sapphire single crystal includes: The first surface and the second surface of the sapphire single crystal are planarized by applying chemical mechanical polishing technology; wherein the chemical solution of the chemical mechanical polishing is a mixture of potassium hydroxide and deionized water in a ratio of 1:10, the abrasive particles are silicon dioxide with an average particle size of 0.05 μm-1 μm, the polishing speed is 100 rpm-120 rpm, and the polishing pressure is 1-5 N / cm 2 , polishing time is 30-60 minutes.

4. The preparation method according to claim 1, It is characterized in that Applying at least one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range, and / or performing atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range, comprising: Apply at least two of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the second surface of the substrate so that the roughness of the second surface reaches a second surface roughness range; Apply one of physical, chemical or mechanical planarization techniques to perform atomic-level planarization on the first surface of the substrate so that the roughness of the first surface reaches a first surface roughness range.

5. The preparation method according to claim 1, It is characterized in that The first surface roughness ranges from 0.01 μm to 1 μm.

6. The preparation method according to claim 1, It is characterized in that The second surface roughness ranges from 0 nm to 0.1 nm.

7. The preparation method according to claim 1, It is characterized in that The physical planarization technology includes one or more of physical vapor deposition, physical etching, ion beam polishing, and magnetron sputtering; the chemical planarization technology includes one or more of wet etching, chemical etching, chemical vapor deposition, and chemical mechanical polishing; the mechanical planarization technology includes precision grinding and polishing processes.

8. The preparation method according to claim 7, It is characterized in that The pressure parameter of the chemical mechanical polishing is 1-5N / cm 2 , the rotation speed is 60-100rpm, and the polishing time is 0.5-2 hours; the chemical solution used in the chemical mechanical polishing is a mixture of potassium hydroxide and deionized water in a ratio of 1:10, and the abrasive particles are silicon dioxide with an average particle size of 0.05μm-1μm.

9. A patterned substrate, It is characterized in that The highly consistent patterned substrate is prepared by the method for preparing the highly consistent patterned substrate as described in any one of claims 1 to 8.

10. An LED epitaxial wafer, It is characterized in that Comprising the patterned substrate as claimed in claim 9.

Images