A composite substrate cleaning method

Abstract

An embodiment of the present invention discloses a composite substrate cleaning method, which first provides a composite substrate; wherein the composite substrate includes a substrate and a heterogeneous microstructure; then, a gas that meets a preset ionization rate condition is used to adjust the interfacial zeta potential of the substrate surface and the interfacial zeta potential of the heterogeneous microstructure surface, respectively; and finally, a cleaning solution is used to clean the composite substrate; wherein the surface of the composite substrate includes byproducts, at least some of which form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the substrate surface and the interfacial zeta potential of the heterogeneous microstructure surface are the same as the interfacial zeta potential of the charged colloidal particles. Utilizing the above method, the interfacial zeta potential of the substrate surface and the interfacial zeta potential of the heterogeneous microstructure surface are reasonably adjusted before cleaning, so that the charged colloidal particles are not easily adsorbed, and the cleaning effect of the composite substrate can be achieved using only one cleaning solution, effectively improving the cleaning efficiency of the composite substrate.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of semiconductor manufacturing technology, and in particular to a composite substrate cleaning method. Background Art

[0002] With the continuous advancement of semiconductor device manufacturing processes, semiconductor devices are becoming smaller and smaller. Even very small impurity particles may affect semiconductor device manufacturing and product performance. Therefore, to reduce manufacturing defects in semiconductor devices, cleaning processes are becoming increasingly important. A reasonable cleaning process can effectively remove impurity particles and prevent them from affecting semiconductor device manufacturing.

[0003] On the one hand, after wafer processing steps such as cutting and etching, the crystal lattice on the wafer surface is in a damaged state, presenting one to several layers of dangling bonds (also known as unsaturated bonds). These dangling bonds are highly chemically active and easily combine with surrounding molecules or atoms, forming adsorption. This adsorption (including physical adsorption and chemical adsorption) is unavoidable. On the other hand, during the cleaning process after wafer processing steps such as cutting and etching, some byproducts on the wafer surface are oxidized and decomposed in the cleaning solution. These byproducts on the wafer surface exist as charged colloids in pure water or the cleaning solution, and these charged colloids easily adsorb to the wafer surface.

[0004] Specifically, for the cleaning process of a composite substrate, after the composite substrate undergoes processing steps such as cutting and etching, the interfacial zeta potentials between the various material layers of the composite substrate may differ significantly, or the interfacial zeta potentials between the various material layers of the composite substrate may be opposite in sign. For example, the composite substrate includes two material layers, wherein the interfacial zeta potential of the first material layer is positive and the interfacial zeta potential of the second material layer is negative. In this case, the charged colloid with a positive interfacial zeta potential will be adsorbed on the second material layer, while the charged colloid with a positive interfacial zeta potential will not be adsorbed on the first material layer. Therefore, it is impossible to simultaneously clean the two material layers of the composite substrate using only one cleaning solution, and the charged colloid will always be adsorbed on one of the material layers. If multiple cleaning solutions are used to clean the two material layers of the composite substrate, other impurity particles may be introduced, which is not conducive to the cleaning efficiency of the composite substrate. Summary of the Invention

[0005] An embodiment of the present invention provides a composite substrate cleaning method, which reasonably adjusts the interfacial zeta potential of the composite substrate surface before cleaning to avoid adsorption of charged colloidal particles during the cleaning process. Only one cleaning solution is used to achieve a clean cleaning effect of the composite substrate, effectively improving the cleaning efficiency of the composite substrate.

[0006] An embodiment of the present invention provides a composite substrate cleaning method, comprising:

[0007] Providing a composite substrate; wherein the composite substrate comprises a base and a heterogeneous microstructure;

[0008] Using a gas that meets a preset ionization rate condition to adjust the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure respectively;

[0009] The composite substrate is cleaned using a cleaning solution; wherein the surface of the composite substrate includes by-products, at least part of the by-products form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the surface of the substrate, the interfacial zeta potential of the surface of the heterogeneous microstructure, and the interfacial zeta potential of the charged colloidal particles are the same.

[0010] Optionally, the surface of the substrate has first dangling bonds, and the surface of the heterogeneous microstructure has second dangling bonds;

[0011] Using a gas that meets a preset ionization rate condition to adjust the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure respectively, comprising:

[0012] In the first reaction stage, under the first preset reaction parameter conditions, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond; wherein, in the cleaning solution, the interfacial zeta potential of the first covalent bond and the interfacial zeta potential of the second covalent bond are the same as the interfacial zeta potential of the charged colloidal particles.

[0013] Optionally, in the first reaction stage, under the first preset reaction parameter conditions, using the gas that meets the preset ionization rate conditions to chemically react with the first dangling bond and the second dangling bond respectively, and correspondingly generating the first covalent bond and the second covalent bond, the method further includes:

[0014] In the second reaction stage, under the second preset reaction parameter conditions, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly; wherein at least one of the reaction parameters of the first preset reaction parameter conditions and the second preset reaction parameter conditions is different.

[0015] Optionally, the reaction parameters of the first preset reaction parameter condition and the second preset reaction parameter condition include at least one of upper electrode power, lower electrode power, gas flow, reaction temperature, reaction pressure and reaction time.

[0016] Optionally, in the first reaction stage, under first preset reaction parameter conditions, using the gas that satisfies a preset ionization rate condition to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generating a first covalent bond and a second covalent bond, including:

[0017] In the first reaction stage, under the conditions of an upper electrode power range of 1400-1600 W and a lower electrode power range of 700-900 W, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively;

[0018] In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including:

[0019] In the second reaction stage, under the conditions of an upper electrode power range of 600-1000W and a lower electrode power range of 0-10W, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly.

[0020] Optionally, in the first reaction stage, under first preset reaction parameter conditions, using the gas that satisfies a preset ionization rate condition to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generating a first covalent bond and a second covalent bond, including:

[0021] In the first reaction stage, under the condition of a gas flow rate range of 100-150 SCCM, the gas meeting the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively;

[0022] In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including:

[0023] In the second reaction stage, under the condition of a gas flow range of 80-100 SCCM, the gas that meets the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

[0024] Optionally, in the first reaction stage, under first preset reaction parameter conditions, using the gas that satisfies a preset ionization rate condition to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generating a first covalent bond and a second covalent bond, including:

[0025] In the first reaction stage, under the reaction temperature range of 120-160° C., the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively;

[0026] In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including:

[0027] In the second reaction stage, under the reaction temperature range of 60-80°C, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

[0028] Optionally, in the first reaction stage, under first preset reaction parameter conditions, using the gas that satisfies a preset ionization rate condition to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generating a first covalent bond and a second covalent bond, including:

[0029] In the first reaction stage, under the condition of a reaction time range of 200-400 seconds, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively;

[0030] In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including:

[0031] In the second reaction stage, under the condition of a reaction time range of 500-700s, the gas that meets the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

[0032] Optionally, in the first reaction stage, under first preset reaction parameter conditions, using the gas that satisfies a preset ionization rate condition to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generating a first covalent bond and a second covalent bond, including:

[0033] In the first reaction stage, under the reaction pressure range of 4-6 Torr, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively;

[0034] In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including:

[0035] In the second reaction stage, under the reaction pressure range of 4-6 Torr, the gas that meets the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

[0036] Optionally, in the first reaction stage, under the first preset reaction parameter conditions, using the gas that meets the preset ionization rate conditions to chemically react with the first dangling bond and the second dangling bond respectively, and before correspondingly generating the first covalent bond and the second covalent bond, the method further includes:

[0037] The composite substrate is placed in an atmosphere of the gas that meets a preset ionization rate condition.

[0038] Optionally, the gas includes at least one of nitrogen, ammonia, hydrogen fluoride, chlorine and boron chloride.

[0039] Optionally, the material of the substrate includes aluminum oxide, and the material of the heterogeneous microstructure includes silicon oxide.

[0040] An embodiment of the present invention provides a composite substrate cleaning method, which includes first providing a composite substrate; wherein the composite substrate includes a base and a heterogeneous microstructure; then using a gas that meets a preset ionization rate condition to adjust the interfacial zeta potential of the surface of the base and the interfacial zeta potential of the surface of the heterogeneous microstructure, respectively; and finally using a cleaning solution to clean the composite substrate; wherein the surface of the composite substrate includes by-products, at least part of the by-products form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the surface of the base, the interfacial zeta potential of the surface of the heterogeneous microstructure, and the interfacial zeta potential of the charged colloidal particles are the same. By utilizing the above method, on the basis of not changing the internal material and structure of the composite substrate, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are reasonably adjusted before cleaning, so as to avoid the adsorption of charged colloidal particles on the surface of the substrate and / or the heterogeneous microstructure due to the principle of "same repulsion, opposite attraction" of the interfacial zeta potential during the cleaning process. Moreover, if the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are the same as the interfacial zeta potential of the charged colloidal particles, the charged colloidal particles are not easily adsorbed, and only one cleaning solution is used to achieve the cleaning effect of the composite substrate, thereby effectively improving the cleaning efficiency of the composite substrate, being beneficial to improving the crystallization quality of the epitaxial layer, inhibiting the sidewall growth of the seed crystal, reducing epitaxial defects, improving the internal quantum efficiency, and improving the production yield of semiconductor devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 1 is a flow chart of a composite substrate cleaning method provided by an embodiment of the present invention;

[0043] Figure 2 This is a schematic diagram of the interfacial zeta potential of an existing composite substrate during the cleaning process;

[0044] Figure 3 is a schematic diagram of the interfacial zeta potential of a composite substrate during a cleaning process provided by an embodiment of the present invention;

[0045] Figure 4 1 is a flow chart of another composite substrate cleaning method provided by an embodiment of the present invention;

[0046] Figure 5 This is a flow chart of another composite substrate cleaning method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0048] 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", and "right" described in the embodiments of the present invention are described based on the angles shown in the accompanying drawings and should not be understood as limiting 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 formed directly "on" or "under" another element, but can also be formed indirectly "on" or "under" another element through an intermediate element. The terms "first", "second", etc. are only used for descriptive purposes and do not indicate 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 according to specific circumstances.

[0049] 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."

[0050] 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 mutual dependence.

[0051] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0052] Figure 1 This is a flow chart of a composite substrate cleaning method provided by an embodiment of the present invention. This embodiment is applicable to the cleaning process of any composite substrate after any preparation process step, such as Figure 1 As shown, the cleaning method includes:

[0053] S110 , providing a composite substrate; wherein the composite substrate includes a base and a heterogeneous microstructure.

[0054] Specifically, a heterogeneous layer can be formed on the surface of a flat substrate using a chemical vapor deposition process, and then the heterogeneous layer can be etched using photolithography and etching processes to obtain multiple heterogeneous microstructures. The entire substrate and heterogeneous microstructures are called a composite substrate. In other words, in one embodiment, the composite substrate includes a substrate and multiple heterogeneous microstructures located on one side of the substrate. The heterogeneous microstructures can be made of one or more materials. The heterogeneous microstructures can also be partially made of a heterogeneous material, with the remaining portion being the same material as the substrate.

[0055] S120 , using a gas that meets a preset ionization rate condition to adjust the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure respectively.

[0056] The preset ionization rate condition is determined based on the reaction rate of the gas and the control requirements of the composite substrate's surface for the interfacial zeta potential. It is understood that when the gas's ionization rate is high, it reacts easily and combines with surrounding molecules or atoms to form chemical bonds. Specifically, if the interfacial zeta potential is not adjusted, the difference between the interfacial zeta potential of the substrate surface and the interfacial zeta potential of the heterogeneous microstructure surface can be significant, or even opposite in sign. Subsequently, charged colloidal particles in the cleaning solution can easily adsorb on the substrate and / or heterogeneous microstructure surfaces, resulting in the composite substrate not being cleaned properly and the adsorption of additional impurity charged colloidal particles. Therefore, before cleaning, a gas that meets the preset ionization rate conditions is reasonably used to adjust the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure, respectively. The purpose of this adjustment process is to make the difference between the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure smaller. In the same cleaning solution, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are of the same positive and negative signs, and are of the same positive and negative signs as the interfacial zeta potential of the charged colloidal particles. Then, the charged colloidal particles will not be adsorbed on the composite substrate, and the cleaning effect of the composite substrate can be achieved by using only one cleaning solution, thereby expanding the applicability of the cleaning solution.

[0057] S130. Cleaning the composite substrate with a cleaning solution; wherein the surface of the composite substrate includes by-products, and at least part of the by-products form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are the same as the interfacial zeta potential of the charged colloidal particles.

[0058] Specifically, Figure 2 This is a schematic diagram of the interfacial zeta potential of an existing composite substrate during the cleaning process, such as Figure 2As shown, this is a process without adjusting the interfacial zeta potential. In one embodiment, the surface of the composite substrate includes byproducts (illustratively, these byproducts may be adsorbed or deposited on the surface of the composite substrate, particularly the side surfaces of substrate 10 and the surface of substrate 10 distal from heterogeneous microstructure 20). At least a portion of these byproducts form charged colloidal particles 30 in the cleaning solution. Exemplarily, the interfacial zeta potential of these charged colloidal particles 30 may be positive. The composite substrate includes substrate 10 and heterogeneous microstructure 20. In the cleaning solution, the interfacial zeta potential of substrate 10 may be negative, while the interfacial zeta potential of heterogeneous microstructure 20 may be positive. Based on the principle of "like repels, opposites attract" of interfacial zeta potential, in the cleaning solution, the charged colloidal particles 30 will adsorb on the surface of substrate 10, but not on the surface of heterogeneous microstructure 20. This results in the problem of incomplete cleaning of substrate 10 and the adsorption of impurities from the charged colloidal particles 30. Using only one cleaning solution cannot achieve the cleaning effect of the substrate 10 and the heterogeneous microstructure 20 at the same time. Figure 3 FIG. 1 is a schematic diagram of the interfacial zeta potential of a composite substrate during the cleaning process provided by an embodiment of the present invention, as shown in FIG. Figure 3 As shown, this is the process of adjusting the interfacial zeta potential. In one embodiment, the surface of the composite substrate includes byproducts, at least some of which form charged colloidal particles 30 in the cleaning solution. Exemplarily, the interfacial zeta potential of the charged colloidal particles 30 can be positive. The composite substrate includes a base 10 and a heterogeneous microstructure 20. The interfacial zeta potential of the base 10 surface can be adjusted from negative to positive, while the interfacial zeta potential of the heterogeneous microstructure 20 surface remains positive. The difference between the interfacial zeta potentials of the base 10 surface and the heterogeneous microstructure 20 surface is small. Based on the principle of "like repels, opposites attract" of interfacial zeta potential, the charged colloidal particles 30 will not be adsorbed on either the surface of the base 10 or the surface of the heterogeneous microstructure 20 in the cleaning solution. Furthermore, impurities such as dust, soluble organic matter, and soluble inorganic matter on the surface of the composite substrate can be removed. Using a single cleaning solution, both the base 10 and the heterogeneous microstructure 20 can be cleaned. Furthermore, if the interfacial zeta potential of the charged colloidal particles 30 is negative, the interfacial zeta potential of the surface of the substrate 10 is adjusted to be negative, and the interfacial zeta potential of the surface of the heterogeneous microstructure 20 is adjusted to be negative, and the difference between the interfacial zeta potential of the surface of the substrate 10 and the interfacial zeta potential of the surface of the heterogeneous microstructure 20 is adjusted to be small. During the cleaning process, the cleaning solution can be selected from acidic solutions, alkaline solutions, neutral solutions, etc. For example, the cleaning solution can be an SPM solution (a mixture of concentrated sulfuric acid and hydrogen peroxide in a certain ratio). This is only an example and is not limiting.

[0059] The technical solution in an embodiment of the present invention first provides a composite substrate; wherein the composite substrate includes a substrate and a heterogeneous microstructure, then uses a gas that meets a preset ionization rate condition to adjust the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure, respectively, and finally uses a cleaning solution to clean the composite substrate; wherein the surface of the composite substrate includes by-products, at least part of the by-products form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the surface of the substrate, the interfacial zeta potential of the surface of the heterogeneous microstructure and the interfacial zeta potential of the charged colloidal particles are the same. By utilizing the above method, on the basis of not changing the internal material and structure of the composite substrate, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are reasonably adjusted before cleaning, so as to avoid the adsorption of charged colloidal particles on the surface of the substrate and / or the heterogeneous microstructure due to the principle of "same repulsion, opposite attraction" of the interfacial zeta potential during the cleaning process. Moreover, if the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are the same as the interfacial zeta potential of the charged colloidal particles, the charged colloidal particles are not easily adsorbed, and only one cleaning solution is used to achieve the cleaning effect of the composite substrate, thereby effectively improving the cleaning efficiency of the composite substrate, being beneficial to improving the crystallization quality of the epitaxial layer, inhibiting the sidewall growth of the seed crystal, reducing epitaxial defects, improving the internal quantum efficiency, and improving the production yield of semiconductor devices.

[0060] Figure 4 This is a flow chart of another composite substrate cleaning method provided by an embodiment of the present invention. This embodiment is optimized based on the above embodiment. Optionally, the surface of the substrate has a first dangling bond, and the surface of the heterogeneous microstructure has a second dangling bond;

[0061] Using a gas that meets a preset ionization rate condition, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are adjusted respectively, including:

[0062] In the first reaction stage, under the first preset reaction parameter conditions, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond; wherein, in the cleaning solution, the interfacial zeta potential of the first covalent bond and the interfacial zeta potential of the second covalent bond are the same as the interfacial zeta potential of the charged colloidal particles.

[0063] For details not yet provided in this embodiment, please refer to the above embodiments. Figure 4 As shown, the cleaning method includes:

[0064] S210 , providing a composite substrate; wherein the composite substrate includes a base and a heterogeneous microstructure.

[0065] S220. In a first reaction stage, under first preset reaction parameter conditions, a gas satisfying a preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond; wherein, in the cleaning solution, the interfacial zeta potential of the first covalent bond and the interfacial zeta potential of the second covalent bond are the same as the interfacial zeta potential of the charged colloidal particles.

[0066] Specifically, in the first reaction stage, under the first preset reaction parameter conditions, the interfacial zeta potential of the substrate and the interfacial zeta potential of the heterogeneous microstructure are regulated. The first reaction stage can be understood as a chemical reaction (chemical bond formation) stage. The reaction parameters of the first preset reaction parameter conditions include at least one of the upper electrode power, the lower electrode power, the gas flow rate, the reaction temperature, the reaction pressure, and the reaction time. Continue to refer to Figure 2 and Figure 3 After the composite substrate undergoes processing steps such as cutting and etching, the lattices on the surfaces of the substrate 10 and the heterogeneous microstructure 20 are in a destroyed state. The surface of the substrate 10 has first dangling bonds, and the surface of the heterogeneous microstructure 20 has second dangling bonds. The first dangling bonds and the second dangling bonds can be understood as unpaired atoms. In the first reaction stage, a gas that meets a preset ionization rate condition can be used. The gas that meets the preset ionization rate condition is ionized under the first preset reaction parameter conditions. The unpaired atoms produced by the gas that meets the preset ionization rate condition easily react chemically with the first dangling bond to form a first covalent bond. The unpaired atoms produced by the gas that meets the preset ionization rate condition easily react chemically with the second dangling bond to form a second covalent bond. It can be understood that in order to avoid the problem that the charged colloidal particles 30 are adsorbed on the surface of the substrate 10 and / or the heterogeneous microstructure 20, resulting in the composite substrate not being cleaned and the charged colloidal particles 30 additionally adsorbing impurities, the interface zeta potential of the first covalent bond and the interface zeta potential of the second covalent bond obtained in the process of adjusting the interface zeta potential are the same as the interface zeta potential of the charged colloidal particles 30.

[0067] In one embodiment, continue to refer to Figure 2 and Figure 3, optionally, the gas includes at least one of nitrogen, ammonia, hydrogen fluoride, chlorine and boron chloride. Optionally, the material of the substrate 10 includes aluminum oxide, and the material of the heterogeneous microstructure 20 includes silicon oxide. Then the first dangling bond on the surface of the substrate 10 can be an unsaturated aluminum bond, and the second dangling bond on the surface of the heterogeneous microstructure 20 can be an unsaturated silicon bond. And in the acidic cleaning solution, the interfacial zeta potential of the saturated silicon-oxygen bond (Si-O bond) on the surface of the substrate 10 is positive, and the interfacial zeta potential of the saturated aluminum-oxygen bond (Al-O bond) on the surface of the heterogeneous microstructure 20 is negative. The by-product in the preparation process is mainly silicon oxide, and the charged colloidal particles 30 formed by silicon oxide in the acidic cleaning solution are silica colloids, and the interfacial zeta potential of silica colloids is positive. In the first reaction stage, under the conditions of the first preset reaction parameters, the unsaturated nitrogen bond formed by nitrogen ionization can be chemically reacted with the unsaturated aluminum bond (two unsaturated bonds are combined into one saturated bond), and a saturated aluminum-nitrogen bond (Al-N bond, i.e., the first covalent bond) is generated accordingly. Similarly, the unsaturated nitrogen bond formed by nitrogen ionization can be chemically reacted with the unsaturated silicon bond (two unsaturated bonds are combined into one saturated bond), and a saturated silicon-nitrogen bond (Si-N bond, i.e., the second covalent bond) is generated accordingly. In the same acidic cleaning solution, the interfacial zeta potential of the saturated silicon-nitrogen bond on the surface of the substrate 10 is positive, and the interfacial zeta potential of the saturated aluminum-nitrogen bond on the surface of the heterogeneous microstructure 20 is positive, and the difference between the interfacial zeta potential of the saturated silicon-nitrogen bond on the surface of the substrate 10 and the interfacial zeta potential of the saturated aluminum-nitrogen bond on the surface of the heterogeneous microstructure 20 is small. The interfacial zeta potential of the saturated silicon-nitrogen bonds on the surface of substrate 10 and the interfacial zeta potential of the saturated aluminum-nitrogen bonds and silicate colloid on the surface of heterogeneous microstructure 20 are both positive, and silicate colloid will not adsorb on the surface of either substrate 10 or heterogeneous microstructure 20. It can be clearly seen that after the interfacial zeta potential adjustment process and cleaning, the number of residual impurity particles on the surface of the composite substrate is significantly reduced.

[0068] Secondly, after the interface zeta potential is adjusted, both saturated silicon-oxygen bonds and saturated silicon-nitrogen bonds exist on the surface of substrate 10, and the properties of the two are similar, which will not affect the subsequent epitaxial crystallization quality. Similarly, after the interface zeta potential is adjusted, both saturated aluminum-oxygen bonds and saturated aluminum-nitrogen bonds exist on the surface of heterogeneous microstructure 20, and the properties of the two are similar, which will not affect the subsequent epitaxial crystallization quality. In addition, the unsaturated aluminum bonds on the surface of substrate 10 are combined with unsaturated nitrogen bonds, and the unsaturated silicon bonds on the surface of heterogeneous microstructure 20 are combined with unsaturated nitrogen bonds, which change the type and number of dangling bonds on the surface of the composite substrate. The number of saturated aluminum-nitrogen bonds formed on the surface of substrate 10 is relatively large, which can be understood as forming a layer of aluminum nitride film on the surface of substrate 10. Similarly, the number of saturated silicon-nitrogen bonds formed on the surface of heterogeneous microstructure 20 is relatively large, which can be understood as forming a layer of silicon nitride film on the surface of heterogeneous microstructure 20. That is, the interfacial zeta potentials of the aluminum nitride film, the silicon nitride film, and the silicate colloid are all positive, and the silicate colloid will not adsorb on either the aluminum nitride film or the silicon nitride film. Furthermore, the difference in interfacial zeta potential between the aluminum nitride film and the silicon nitride film is small.

[0069] S230. Cleaning the composite substrate with a cleaning solution; wherein the surface of the composite substrate includes by-products, and at least part of the by-products form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are the same as the interfacial zeta potential of the charged colloidal particles.

[0070] Figure 5 This is a flow chart of another composite substrate cleaning method provided by an embodiment of the present invention. This embodiment is optimized based on the above embodiment. Optionally, the surface of the substrate has a first dangling bond, and the surface of the heterogeneous microstructure has a second dangling bond;

[0071] Using a gas that meets a preset ionization rate condition, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are adjusted respectively, including:

[0072] In the first reaction stage, under the first preset reaction parameter conditions, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond; wherein, in the cleaning solution, the interfacial zeta potential of the first covalent bond and the interfacial zeta potential of the second covalent bond are the same as the interfacial zeta potential of the charged colloidal particles.

[0073] Furthermore, in the first reaction stage, under the first preset reaction parameter conditions, a gas satisfying the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and after correspondingly generating the first covalent bond and the second covalent bond, the method further includes:

[0074] In the second reaction stage, under the second preset reaction parameter conditions, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond; wherein at least one of the reaction parameters of the first preset reaction parameter conditions and the second preset reaction parameter conditions is different.

[0075] Furthermore, in the first reaction stage, under the first preset reaction parameter conditions, using a gas that meets the preset ionization rate conditions to chemically react with the first dangling bond and the second dangling bond, respectively, and before correspondingly generating the first covalent bond and the second covalent bond, the method further includes:

[0076] The composite substrate is placed in an atmosphere of a gas that meets a preset ionization rate condition.

[0077] For details not yet provided in this embodiment, please refer to the above embodiments. Figure 5 As shown, the cleaning method includes:

[0078] S310 , providing a composite substrate; wherein the composite substrate includes a base and a heterogeneous microstructure.

[0079] S320, placing the composite substrate in an atmosphere of a gas that meets a preset ionization rate condition.

[0080] Specifically, in one embodiment, after the composite substrate has undergone processing steps such as cutting and etching, it is not necessary to remove the composite substrate from the etching chamber; that is, the interface zeta potential adjustment process for the composite substrate continues within the etching chamber. For example, the etching chamber can be purged with a gas meeting a preset ionization rate condition. This purging process can last for 2-4 minutes. This purging process can effectively expel byproduct gases and other interfering gases produced during the composite substrate etching process from the etching chamber, thereby preventing these byproduct gases and other interfering gases from affecting the subsequent interface zeta potential adjustment process.

[0081] After the purge process, the composite substrate can be placed in an atmosphere of a gas that meets the preset ionization rate condition under the third preset reaction parameter condition in the preliminary diffusion stage (for example, the composite substrate is still in the etching chamber). The reaction parameters of the third preset reaction parameter condition may include upper electrode power, lower electrode power, gas flow rate, reaction temperature, reaction pressure and reaction time. Among them, the upper electrode power and the lower electrode power can be zero, the gas flow rate range can be 250-400 SCCM, the reaction temperature range can be 25-35°C, the reaction pressure range can be 4-6 Torr, and the reaction time of the purge process can be 200-500s. In the preliminary diffusion stage, the diffusion of the gas that meets the preset ionization rate condition can be effectively promoted, so that the gas that meets the preset ionization rate condition moves to the surface of the composite substrate, thereby increasing the concentration of the gas that meets the preset ionization rate condition at the surface of the composite substrate, laying a good foundation for the subsequent gas that meets the preset ionization rate condition to fully react with the first dangling bond on the surface of the substrate and fully react with the second dangling bond on the surface of the heterogeneous microstructure, thereby promoting the adjustment process of the interface zeta potential. In particular, this can also avoid the problem of oxygen combining with dangling bonds on the surface of the composite substrate, thereby forming an oxide film. If an oxide film forms on the surface of the composite substrate, this oxide film will affect the optical and chemical properties of the composite substrate, such as reducing light transmittance and increasing surface energy, which is detrimental to the interface quality between the composite substrate and the epitaxial layer, as well as the light extraction efficiency of the composite substrate. After this initial diffusion stage, the type of dangling bonds on the surface of the composite substrate can be changed from oxygen bonds with a higher affinity to nitrogen bonds with a lower affinity, thus avoiding the formation of an oxide film. Optionally, the gas includes at least one of nitrogen, ammonia, hydrogen fluoride, chlorine, and boron chloride.

[0082] S330. In a first reaction stage, under first preset reaction parameter conditions, a gas satisfying a preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and generate a first covalent bond and a second covalent bond correspondingly; wherein, in the cleaning solution, the interfacial zeta potential of the first covalent bond and the interfacial zeta potential of the second covalent bond are the same as the interfacial zeta potential of the charged colloidal particles.

[0083] S340. In the second reaction stage, under the second preset reaction parameter conditions, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond; wherein at least one of the reaction parameters of the first preset reaction parameter conditions and the second preset reaction parameter conditions is different.

[0084] Specifically, in the second reaction stage, under the second preset reaction parameter conditions, the process of adjusting the interfacial zeta potential of the substrate and the interfacial zeta potential of the heterogeneous microstructure is continued. The second reaction stage can be understood as a chemical reaction (chemical bond formation) stage. The reaction parameters of the second preset reaction parameter conditions include at least one of the upper electrode power, the lower electrode power, the gas flow rate, the reaction temperature, the reaction pressure and the reaction time. Continue to refer to Figure 2 and Figure 3 In the first reaction phase of the composite substrate, the unpaired atoms produced by the gas that meets the preset ionization rate condition easily chemically react with the first dangling bonds to form first covalent bonds, and the unpaired atoms produced by the gas that meets the preset ionization rate condition easily chemically react with the second dangling bonds to form second covalent bonds. However, some of the first covalent bonds and / or second dangling bonds may not be combined with the unpaired atoms produced by the gas that meets the preset ionization rate condition, resulting in incomplete adjustment of the interface zeta potential on the surface of the composite substrate and unstable interface zeta potential on the surface of the composite substrate. In the second reaction phase, the gas that meets the preset ionization rate condition is continued to be used. The gas that meets the preset ionization rate condition is ionized under the second preset reaction parameter conditions. The unpaired atoms produced by the gas that meets the preset ionization rate condition chemically react with the remaining first dangling bonds to form first covalent bonds, and the unpaired atoms produced by the gas that meets the preset ionization rate condition chemically react with the remaining second dangling bonds to form second covalent bonds. The first dangling bonds on the surface of the substrate 10 and the second dangling bonds on the surface of the heterogeneous microstructure 20 are ensured to combine with the unpaired atoms generated by the gas that meets the preset ionization rate conditions, thereby improving the stability of the interfacial zeta potential on the surface of the composite substrate. Optionally, the reaction parameters of the first and second preset reaction parameter conditions include at least one of upper electrode power, lower electrode power, gas flow rate, reaction temperature, reaction pressure, and reaction time. This ensures that the unpaired atoms generated by the gas that meets the preset ionization rate conditions fully combine with the first and second dangling bonds, respectively.

[0085] In one embodiment, continue to refer to Figure 2 and Figure 3, optionally, the gas includes at least one of nitrogen, ammonia, hydrogen fluoride, chlorine and boron chloride. Optionally, the material of the substrate 10 includes aluminum oxide, and the material of the heterogeneous microstructure 20 includes silicon oxide. Then the first dangling bond on the surface of the substrate 10 can be an unsaturated aluminum bond, and the second dangling bond on the surface of the heterogeneous microstructure 20 can be an unsaturated silicon bond. In the second reaction stage, under the second preset reaction parameter conditions, the unsaturated nitrogen bond formed by nitrogen ionization can be chemically reacted with the remaining unsaturated aluminum bond (two unsaturated bonds are combined into one saturated bond), and a saturated aluminum-nitrogen bond (Al-N bond, i.e., the first covalent bond) is generated accordingly. Similarly, the unsaturated nitrogen bond formed by nitrogen ionization can be chemically reacted with the remaining unsaturated silicon bond (two unsaturated bonds are combined into one saturated bond), and a saturated silicon-nitrogen bond (Si-N bond, i.e., the second covalent bond) is generated accordingly. The number of unsaturated aluminum bonds on the surface of the substrate 10 and the number of unsaturated silicon bonds on the surface of the heterogeneous microstructure 20 are greatly reduced. The correspondingly generated saturated aluminum-nitrogen bonds and saturated silicon-nitrogen bonds are highly reactive but lack stability, necessitating curing in a second reaction stage under second preset reaction parameters to enhance the stability of the saturated aluminum-nitrogen bonds (also understood as the aluminum nitride film) and saturated silicon-nitrogen bonds (also understood as the silicon nitride film). Furthermore, the unsaturated nitrogen bonds formed by nitrogen ionization can combine with the unsaturated nitrogen bonds on the surface of the composite substrate after the first reaction stage, effectively reducing the number of dangling bonds on the composite substrate's surface and preventing the formation of an oxide film from combining with unsaturated oxygen bonds on the composite substrate's surface.

[0086] After the second reaction phase, the chamber is still purged with a gas meeting the preset ionization rate requirements to cool the composite substrate. After cooling, the composite substrate is cleaned with a cleaning solution to prevent damage and cracking caused by extreme thermal fluctuations.

[0087] S350. Cleaning the composite substrate with a cleaning solution; wherein the surface of the composite substrate includes by-products, and at least part of the by-products form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure are the same as the interfacial zeta potential of the charged colloidal particles.

[0088] Furthermore, in the first reaction stage, under the conditions of the first preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the first reaction stage, under the conditions of the upper electrode power range of 1400-1600W and the lower electrode power range of 700-900W, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond; in the second reaction stage, under the conditions of the second preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the second reaction stage, under the conditions of the upper electrode power range of 600-1000W and the lower electrode power range of 0-10W, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond.

[0089] For example, in the first reaction stage, the upper electrode power can be adjusted to 1400W and the lower electrode power can be adjusted to 800W. A gas that meets the preset ionization rate conditions is used to chemically react with the first and second dangling bonds, respectively, to generate the first and second covalent bonds. In the second reaction stage, the upper electrode power can be adjusted to 1000W and the lower electrode power can be adjusted to 0W. A gas that meets the preset ionization rate conditions is used to chemically react with the first and second dangling bonds, respectively, to generate the first and second covalent bonds.

[0090] Furthermore, in the first reaction stage, under the conditions of the first preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the first reaction stage, under the conditions of the gas flow rate range of 100-150SCCM, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond; in the second reaction stage, under the conditions of the second preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the second reaction stage, under the conditions of the gas flow rate range of 80-100SCCM, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond.

[0091] For example, in the first reaction stage, the gas flow rate can be adjusted to 100 SCCM, and a gas that meets the preset ionization rate condition is used to chemically react with the first and second dangling bonds, respectively, to form the first and second covalent bonds. In the second reaction stage, the gas flow rate can be adjusted to 80 SCCM, and a gas that meets the preset ionization rate condition is used to chemically react with the first and second dangling bonds, respectively, to form the first and second covalent bonds.

[0092] Furthermore, in the first reaction stage, under the conditions of the first preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the first reaction stage, under the conditions of the reaction temperature range of 120-160°C, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond; in the second reaction stage, under the conditions of the second preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the second reaction stage, under the conditions of the reaction temperature range of 60-80°C, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond.

[0093] For example, in the first reaction stage, the reaction temperature can be adjusted to 120°C, and a gas that meets the preset ionization rate conditions is used to chemically react with the first and second dangling bonds, respectively, to form the first and second covalent bonds. In the second reaction stage, the reaction temperature can be adjusted to 80°C, and a gas that meets the preset ionization rate conditions is used to chemically react with the first and second dangling bonds, respectively, to form the first and second covalent bonds.

[0094] Furthermore, in the first reaction stage, under the conditions of the first preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the first reaction stage, under the conditions of the reaction time range of 200-400s, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond; in the second reaction stage, under the conditions of the second preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the second reaction stage, under the conditions of the reaction time range of 500-700s, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond.

[0095] For example, in the first reaction stage, the reaction time can be adjusted to 300 seconds, and a gas that meets the preset ionization rate condition is used to chemically react with the first and second dangling bonds, respectively, to generate the first and second covalent bonds. In the second reaction stage, the reaction time can be adjusted to 500 seconds, and a gas that meets the preset ionization rate condition is used to chemically react with the first and second dangling bonds, respectively, to generate the first and second covalent bonds.

[0096] Furthermore, in the first reaction stage, under the conditions of the first preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the first reaction stage, under the conditions of the reaction pressure range of 4-6Torr, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond; in the second reaction stage, under the conditions of the second preset reaction parameters, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond, including: in the second reaction stage, under the conditions of the reaction pressure range of 4-6Torr, a gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate the first covalent bond and the second covalent bond.

[0097] For example, in the first reaction stage, the reaction pressure can be adjusted to 5 Torr, and a gas that meets the preset ionization rate condition is used to chemically react with the first and second dangling bonds, respectively, to form the first and second covalent bonds. In the second reaction stage, the reaction pressure can be adjusted to 5 Torr, and a gas that meets the preset ionization rate condition is used to chemically react with the first and second dangling bonds, respectively, to form the first and second covalent bonds.

[0098] Optionally, the reaction parameters of the first and second preset reaction parameter conditions include at least one of upper electrode power, lower electrode power, gas flow rate, reaction temperature, reaction pressure, and reaction time. In one specific embodiment, in the first reaction stage, under the conditions of an upper electrode power range of 1400-1600 W, a lower electrode power range of 700-900 W, a gas flow rate range of 100-150 SCCM, a reaction temperature range of 120-160° C., a reaction time range of 200-400 s, and a reaction pressure range of 4-6 Torr, a gas meeting the preset ionization rate conditions is used to chemically react with the first and second dangling bonds, respectively, to form first and second covalent bonds, respectively. Under the above-mentioned first preset reaction parameter conditions, the isotropic etching / reaction rate of the composite substrate is stable, does not affect the contact angle of the composite substrate, and can maintain the surface hydrophobicity of the composite substrate. The gas meeting the preset ionization rate conditions can chemically react with the dangling bonds on the surface of the composite substrate to form new covalent bonds, thereby changing the type and number of dangling bonds on the surface of the composite substrate. In the second reaction stage, under the conditions of an upper electrode power range of 600-1000W, a lower electrode power range of 0-10W, a gas flow rate range of 80-100 SCCM, a reaction temperature range of 60-80°C, a reaction time range of 500-700s, and a reaction pressure range of 4-6 Torr, a gas meeting the preset ionization rate conditions is used to chemically react with the first and second dangling bonds, respectively, to form the first and second covalent bonds, respectively. That is, the first and second reaction stages are carried out under the combined influence of the reaction parameters of upper electrode power, lower electrode power, gas flow rate, reaction temperature, reaction pressure, and reaction time. Under the above-mentioned second preset reaction parameters, the gas meeting the preset ionization rate conditions can further chemically react with the remaining dangling bonds on the surface of the composite substrate, effectively reducing the number of dangling bonds on the surface of the composite substrate, facilitating the solidification of the generated covalent bonds (also understood as a thin film), and improving the stability of the generated covalent bonds (also understood as a thin film).

[0099] In another specific embodiment, the composite substrate includes a base and a heterogeneous microstructure, wherein the base may be made of aluminum oxide, and the interface zeta potential of the base surface is negative; the heterogeneous microstructure may be made of silicon oxide, and the interface zeta potential of the heterogeneous microstructure surface is positive. The impurity particles remaining on the surface are charged colloidal particles, which may be silica colloids. Ten thousand silicon oxide patterned composite sapphire substrate etching wafers are treated using surface treatment conditions and normal conditions, respectively, and then pickled and dried under the same conditions, and all cleaned wafers are subjected to AOI (automated optical inspection). The surface treatment conditions are to adjust the interface zeta potential of the base surface and the interface zeta potential of the heterogeneous microstructure in the composite substrate, and then use a cleaning solution to clean the composite substrate. The normal conditions are to directly use a cleaning solution to clean the composite substrate without adjusting the interface zeta potential of the base surface and the interface zeta potential of the heterogeneous microstructure in the composite substrate. The analysis and statistics of multiple cleaning processes are performed to determine the number of residual impurity particles on the surface of the composite substrate after cleaning corresponding to the surface treatment conditions and the number of residual impurity particles on the surface of the composite substrate after cleaning corresponding to the normal conditions.

[0100] Table 1 is a schematic table showing the distribution of the number of surface particles remaining on the wafer after cleaning under a surface treatment condition and normal conditions provided by an embodiment of the present invention. Table 2 is a schematic table showing the distribution ratio of the surface particles remaining on the wafer after cleaning under a surface treatment condition and normal conditions provided by an embodiment of the present invention. Table 3 is a schematic table showing the overall data summary of the surface particles remaining on the wafer after cleaning under a surface treatment condition and normal conditions provided by an embodiment of the present invention. As shown in Tables 1, 2 and 3, it can be seen that: (1) under the surface treatment conditions, when the number of residual impurity particles on the surface of the composite substrate is in the range of 0-9, the corresponding proportion of the number of composite substrates in the total amount is the largest, and is much larger than the sum of the proportions of the number of residual impurity particles on the surface of the composite substrate when the number of residual impurity particles on the surface of the composite substrate is in the range of 10-100. It can be seen that the reasonable adjustment of the interface zeta potential of the surface of the substrate and the interface zeta potential of the surface of the heterogeneous microstructure is beneficial to the cleaning efficiency of the composite substrate and greatly reduces the number of residual impurity particles on the surface of the composite substrate. (2) When the number of residual impurity particles on the surface of the composite substrate ranges from 0 to 9, the proportion of the number of composite substrates corresponding to the surface treatment conditions to the total number is much greater than the proportion of the number of composite substrates corresponding to the normal conditions to the total number. This shows that the reasonable adjustment of the interface zeta potential of the substrate surface and the interface zeta potential of the heterogeneous microstructure surface makes the cleaning degree of the composite substrate corresponding to the surface treatment conditions better than the cleaning degree of the composite substrate corresponding to the normal conditions. (3) When a large number of composite substrates are cleaned under the surface treatment conditions, the average number of residual impurity particles on the surface of the composite substrate is 5.5, which is less than the average number of residual impurity particles on the surface of the composite substrate when a large number of composite substrates are cleaned under the normal conditions, which is 30.3. This shows that the number of residual impurity particles on the surface of the composite substrate corresponding to the surface treatment conditions is smaller, effectively avoiding the adsorption of silica colloid on the surface of the composite substrate, and the composite substrate corresponding to the surface treatment conditions is cleaned more cleanly.

[0101] Table 1

[0102] condition 0-9 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99 >100 Surface treatment conditions 17962 2060 778 408 235 153 106 61 38 36 141 Normal conditions 4412 8740 5800 3076 2112 1164 756 476 404 244 888

[0103] Table 2

[0104] condition 0-9 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99 >100 Surface treatment conditions 81.7％ 9.4％ 3.5％ 1.9％ 1.1％ 0.7％ 0.5％ 0.3％ 0.2％ 0.2％ 0.6％ Normal conditions 15.7％ 31.1％ 20.7％ 11.0％ 7.5％ 4.1％ 2.7％ 1.7％ 1.4％ 0.9％ 3.2％

[0105] Table 3

[0106]

[0107] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations, and substitutions are possible for those skilled in the art without departing from the scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A composite substrate cleaning method, characterized in that: include: Providing a composite substrate; wherein the composite substrate comprises a base and a heterogeneous microstructure; Using a gas that meets a preset ionization rate condition to adjust the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure respectively; The composite substrate is cleaned using a cleaning solution; wherein the surface of the composite substrate includes byproducts, at least some of the byproducts form charged colloidal particles in the cleaning solution, and in the cleaning solution, the interfacial zeta potential of the surface of the substrate, the interfacial zeta potential of the surface of the heterogeneous microstructure, and the interfacial zeta potential of the charged colloidal particles are the same; The surface of the substrate has first dangling bonds, and the surface of the heterogeneous microstructure has second dangling bonds; Using a gas that meets a preset ionization rate condition to adjust the interfacial zeta potential of the surface of the substrate and the interfacial zeta potential of the surface of the heterogeneous microstructure respectively, comprising: In the first reaction stage, under the first preset reaction parameter conditions, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond; wherein, in the cleaning solution, the interfacial zeta potential of the first covalent bond and the interfacial zeta potential of the second covalent bond are the same as the interfacial zeta potential of the charged colloidal particles.

2. The cleaning method according to claim 1, wherein In the first reaction stage, under the first preset reaction parameter conditions, the gas satisfying the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and a first covalent bond and a second covalent bond are generated accordingly, further comprising: In the second reaction stage, under the second preset reaction parameter conditions, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly; wherein at least one of the reaction parameters of the first preset reaction parameter conditions and the second preset reaction parameter conditions is different.

3. The cleaning method according to claim 2, wherein The reaction parameters of the first preset reaction parameter condition and the second preset reaction parameter condition include at least one of upper electrode power, lower electrode power, gas flow, reaction temperature, reaction pressure and reaction time.

4. The cleaning method according to claim 3, wherein In a first reaction stage, under first preset reaction parameter conditions, the gas satisfying a preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond, including: In the first reaction stage, under the conditions of an upper electrode power range of 1400-1600 W and a lower electrode power range of 700-900 W, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively; In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including: In the second reaction stage, under the conditions of an upper electrode power range of 600-1000W and a lower electrode power range of 0-10W, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly.

5. The cleaning method according to claim 3, wherein: In a first reaction stage, under first preset reaction parameter conditions, the gas satisfying a preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond, including: In the first reaction stage, under the condition of a gas flow rate range of 100-150 SCCM, the gas meeting the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively; In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including: In the second reaction stage, under the condition of a gas flow range of 80-100 SCCM, the gas that meets the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

6. The cleaning method according to claim 3, wherein: In a first reaction stage, under first preset reaction parameter conditions, the gas satisfying a preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond, including: In the first reaction stage, under the reaction temperature range of 120-160° C., the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively; In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including: In the second reaction stage, under the reaction temperature range of 60-80°C, the gas that meets the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

7. The cleaning method according to claim 3, wherein: In a first reaction stage, under first preset reaction parameter conditions, the gas satisfying a preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond, including: In the first reaction stage, under the condition of a reaction time range of 200-400 seconds, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively; In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including: In the second reaction stage, under the condition of a reaction time range of 500-700s, the gas that meets the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

8. The cleaning method according to claim 3, wherein: In a first reaction stage, under first preset reaction parameter conditions, the gas satisfying a preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and correspondingly generate a first covalent bond and a second covalent bond, including: In the first reaction stage, under the reaction pressure range of 4-6 Torr, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, to generate the first covalent bond and the second covalent bond respectively; In the second reaction stage, under the second preset reaction parameter conditions, the gas satisfying the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond, respectively, and the first covalent bond and the second covalent bond are generated accordingly, including: In the second reaction stage, under the reaction pressure range of 4-6 Torr, the gas that meets the preset ionization rate condition is used to chemically react with the first dangling bond and the second dangling bond respectively, and the first covalent bond and the second covalent bond are generated accordingly.

9. The cleaning method according to claim 2, wherein: In the first reaction stage, under the first preset reaction parameter conditions, the gas satisfying the preset ionization rate conditions is used to chemically react with the first dangling bond and the second dangling bond, respectively, and before the first covalent bond and the second covalent bond are generated respectively, the method further includes: The composite substrate is placed in an atmosphere of the gas that meets a preset ionization rate condition.

10. The cleaning method according to claim 9, characterized in that: The gas includes at least one of nitrogen, ammonia, hydrogen fluoride, chlorine and boron chloride.

11. The cleaning method according to claim 1, wherein The material of the substrate includes aluminum oxide, and the material of the heterogeneous microstructure includes silicon oxide.

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