CN117534508A

CN117534508A - Ceramic roughening method

Info

Publication number: CN117534508A
Application number: CN202311550746.5A
Authority: CN
Inventors: 陶克文; 余佳妍; 尹福章; 林建威; 罗雄科
Original assignee: Shanghai Zenfocus Semi Tech Co ltd
Current assignee: Shanghai Zenfocus Semi Tech Co ltd
Priority date: 2023-11-20
Filing date: 2023-11-20
Publication date: 2024-02-09

Abstract

The application provides a ceramic roughening method, which comprises the following steps: configuring plasma gas according to ceramic characteristics, and filling the plasma gas into the ceramic substrate with initial roughness; adjusting process parameters, wherein the active plasmas ionized by the plasma gas through high-frequency glow discharge reaction react with target components in the initial roughness ceramic substrate, and the reaction rates of the active plasmas and different oxidation components in the ceramic substrate are different, so that the ceramic substrate with the target roughness is obtained; wherein the target roughness is greater than the initial roughness. The embodiment of the specification obtains a good and uniform ceramic substrate surface, and the whole ceramic substrate surface is of a cellular micropore structure, so that the surface does not influence the performance of the substrate, increases the bonding area and has good adhesion and binding force.

Description

Ceramic roughening method

Technical Field

The application relates to the technical field of semiconductor test substrates, in particular to a ceramic coarsening method, in particular to a LTCC low-temperature co-fired ceramic substrate mixed circuit substrate technology.

Background

The corresponding ceramic substrate is required to have very high planar flatness during semiconductor wafer testing. The ceramic substrate needs to be subjected to fine grinding and polishing treatment to meet the requirement of flatness. However, the polished ceramic surface is mirror-smooth, and when the glue or copper plating is performed on the mirror-smooth ceramic substrate, the adhesion and binding force are very weak, and the influence on the glue or copper plating is large. Therefore, roughening treatment is required for the smooth ceramic surface.

There are various substrate types according to the manufacturing process, including LTCC ceramic substrates, which have warpage and large surface roughness after firing, so that the method cannot be directly applied to thin film circuit processes to manufacture more precise wiring layers. Therefore, the LTCC ceramic substrate needs to be further ground and polished, but the polished LTCC ceramic substrate has small surface roughness, and the bonding force between the ceramic and a PVD coating and a dielectric layer of a subsequent process is poor, so that the surface roughening treatment of the LTCC ceramic is needed.

Common roughening methods include etching with hydrofluoric acid (HF) and sulfuric acid (H ₂ SO ₄ ) And (5) solution corrosion. The two solutions are hazardous substances no matter through dissolving the surface of the ceramic substrate or carrying out chemical reaction with the components on the surface of the ceramic substrate, and because of corrosiveness, toxicity and the like, the two solutions need to be operated under strict and safe conditions, and pollution discharge treatment of the reaction is also needed according to use restrictions and the like, so that the process is complicated. With the improvement of the requirements of environmental assessment, the volatility and corrosiveness of the two solutions cause higher process requirements and more severe requirements on use control and pollution discharge. And the two solutions are dangerous chemicals, once the coarsening degree is too high due to improper control, the adhesion of the coating is reduced, the structure is damaged, and the like, and finally the coarsening effect of the surface of the ceramic substrate is poor.

Thus, a new ceramic roughening treatment scheme is needed.

Disclosure of Invention

In view of this, the embodiments of the present disclosure provide a ceramic roughening method applied to a process of testing an LTCC ceramic substrate.

The embodiment of the specification provides the following technical scheme:

embodiments of the present disclosure provide a ceramic roughening method, including:

configuring plasma gas according to ceramic characteristics, and filling the plasma gas into the ceramic substrate with initial roughness;

adjusting process parameters, wherein the active plasmas ionized by the plasma gas through high-frequency glow discharge reaction react with target components in the initial roughness ceramic substrate, and the reaction rates of the active plasmas and different oxidation components in the ceramic substrate are different, so that the ceramic substrate with the target roughness is obtained; wherein the target roughness is greater than the initial roughness.

Compared with the prior art, the beneficial effects that above-mentioned at least one technical scheme that this description embodiment adopted can reach include at least:

different plasma gases are configured for different ceramic substrates, the plasma gases are filled in plasma equipment, heating and high-frequency glow discharge are carried out, active plasmas are ionized to react with target components on the surfaces of the substrates, crystal grains with different structures and sizes are inevitably generated due to the fact that oxide components of the ceramic substrates are different and crystallization exists in the firing process, different reaction rates are achieved between the components of the different crystal grains and the active plasmas, and therefore roughness of ceramic surface demand effects is achieved through controlling process parameters of the active plasmas, for example, the roughness is about 0.4um, good and uniform roughened surfaces are obtained, the surfaces are of cellular microporous structures, the performances of the substrates are not affected, the bonding area is increased, and good adhesion and binding force are achieved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic illustration of coarsening a ceramic substrate in the present application;

FIG. 2 is a flow chart of a ceramic roughening process in the present application;

fig. 3 is a schematic view showing the effect of roughening the surface of the ceramic substrate.

Detailed Description

Embodiments of the present application are described in detail below with reference to the accompanying drawings.

Other advantages and effects of the present application will become apparent to those skilled in the art from the present disclosure, when the following description of the embodiments is taken in conjunction with the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. The present application may be embodied or carried out in other specific embodiments, and the details of the present application may be modified or changed from various points of view and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

It is noted that various aspects of the embodiments are described below within the scope of the following claims. It should be apparent that the aspects described herein may be embodied in a wide variety of forms and that any specific structure and/or function described herein is merely illustrative. Based on the present application, one skilled in the art will appreciate that one aspect described herein may be implemented independently of any other aspect, and that two or more of these aspects may be combined in various ways. For example, apparatus may be implemented and/or methods practiced using any number and aspects set forth herein. In addition, such apparatus may be implemented and/or such methods practiced using other structure and/or functionality in addition to one or more of the aspects set forth herein.

It should also be noted that the illustrations provided in the following embodiments merely illustrate the basic concepts of the application by way of illustration, and only the components related to the application are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.

In addition, in the following description, specific details are provided in order to provide a thorough understanding of the examples. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details.

In the test of semiconductor wafers, a multilayer ceramic substrate needs to be attached, and according to different manufacturing processes, the substrate types include a low-temperature co-fired multilayer ceramic substrate (LTCC), a high-temperature co-fired multilayer ceramic substrate (HTCC), a direct bonding copper substrate (DBC) and a direct copper plating substrate (DPC).

The existing LTCC ceramic substrate has the problems of warpage, large surface roughness and the like after firing, so that the LTCC ceramic substrate cannot be directly applied to a thin film circuit process to manufacture a more precise wiring layer. Therefore, the LTCC ceramic substrate needs to be further ground and polished, but the surface roughness of the polished LTCC ceramic substrate is small, so that the bonding force between the ceramic and a PVD coating and a dielectric layer in the subsequent process is poor, and roughening treatment is needed to be carried out on the surface of the LTCC ceramic.

The roughening of the multilayer ceramic substrate of the prior art generally employs hydrofluoric acid (HF) etching and sulfuric acid (H ₂ SO ₄ ) And (3) solution corrosion reaction. For example, sulfuric acid (H) ₂ SO ₄ ) The solution corrodes the material surface, sulfuric acid and the components on the ceramic surface generate chemical reaction, the roughness uniformity is poor due to concentration polarization and other factors of the solution reaction, irregular pits and cracks exist, and the roughening effect is poor. Because sulfuric acid belongs to a third type of easily-made toxic hazardous chemical substance, the requirement on coarsening environment is high, and the reaction pollution discharge treatment is required according to the use limit and the like, so that the process is complicated. And for example, hydrofluoric acid (HF) etching is adopted to dissolve a glass phase of a ceramic surface to form a rough surface so as to improve the bonding force, but hydrofluoric acid is a hazardous chemical, the volatility, corrosiveness and toxicity of the hydrofluoric acid cause great limitation on use, and the requirements of reaction pollution discharge and the like can be met according to the use control.

With the improvement of the requirements of the environmental assessment, the use control of the two roughening solutions is increased, and the process requirements are high. In addition, if the coarsening solution is used for coarsening, the adhesion of the coating can be reduced if the coarsening solution is improperly controlled, and the structure can be damaged when the coarsening solution is severe. Thereby the coarsening process is uncontrollable and the risk is high.

It is found that if the conventional plasma etching method is adopted for the ceramic substrate, new solidified matters are generated in the reaction process of the ceramic substrate, so that further reaction is prevented, and the surface of the ceramic substrate cannot be reacted by adopting the conventional plasma etching method.

In view of this, the inventors have found that the presence of devitrification during firing of ceramic substrates results in the generation of grains of different structures and sizes, resulting in different ceramic substrate structures. But at the same time the plasma gas was found to react at a different rate with different oxides. The ceramic component has anisotropy, the reaction rates of the active plasma and the components in the ceramic substrate are different, and the reaction products are different, wherein the micro-etching degree of part of the tissues is high, the micro-etching degree of the rest of the tissues is low or the tissues are not corroded at all, and part of the reaction products have the characteristic of volatilization and are easy to clean through vacuum adsorption. Based on the method, the micro-etching degree of different components is regulated and controlled through the technological parameters, so that uneven pits appear on the surface of the substrate, and the roughness of the ceramic surface can be accurately regulated and controlled.

According to the embodiment of the specification, on the premise of not affecting the performance (flatness, substrate electrical property, mechanical property, air tightness and the like) of the substrate, the ceramic substrate can be roughened efficiently and stably by controlling the concentration of plasma, the processing time and different reaction gas components.

Based on the above, the embodiments of the present disclosure provide a new ceramic roughening scheme, specifically adapting a plasma gas according to ceramic characteristics, and filling the plasma gas into a ceramic substrate with initial roughness; adjusting process parameters, wherein the active plasmas ionized by the plasma gas through high-frequency glow discharge reaction react with target components in the initial roughness ceramic substrate, and the reaction rates of the active plasmas and different oxidation components in the ceramic substrate are different, so that the ceramic substrate with the target roughness is obtained; wherein the target roughness is greater than the initial roughness. Wherein the surface of the ceramic substrate is cleaned before each step of the reaction between the ceramic substrate and the plasma gas.

The surface of the substrate with the target roughness is not provided with pits or cracks, and the whole substrate is of a cellular micropore structure, so that a good and uniform roughened surface of the ceramic substrate is obtained. Not only improves the effect of the roughening treatment of the ceramic surface, but also realizes the roughening operation in a safe and convenient environment, and solves various limit defects of using scenes or etching liquid in the roughening process of the ceramic surface in the prior art.

According to the experimental result, the substrate with the target roughness is a ceramic substrate with the roughness of about 0.4um, the whole surface is in a honeycomb micropore structure, and the film base has good bonding performance.

The following describes the technical solutions provided by the embodiments of the present application with reference to the accompanying drawings.

As illustrated in fig. 2, the ceramic roughening method provided in the embodiments of the present disclosure includes steps S210 to S220. In step S210, the plasma gas is adapted according to the ceramic characteristics, and is filled into the substrate with the initial roughness. Step S220, adjusting process parameters, wherein the active plasmas ionized by the plasma gas through high-frequency glow discharge reaction react with target components in the initial roughness substrate, and the reaction rates of the active plasmas and different oxidation components in the ceramic substrate are different, so that the ceramic substrate with target roughness is obtained; wherein the target roughness is greater than the initial roughness. The ceramic substrate of initial roughness in some embodiments is smooth (roughness <0.05 um).

It has been found that common low temperature cofired ceramic substrates (LTCC), typically a composite of crystals and glass, have a major composition of Al ₂ O ₃ 、SiO ₂ Common oxides such as CaO, mgO, znO. The chemical bond energy of Si-O (4.25 eV) is low, and the chemical reaction rate with halogen corrosive gas is high; the Al-O chemical bond energy (76.9 eV) is higher, and the chemical reaction rate with halogen corrosive gas is slower; the bond energy of the rest Ca-O and the like is higher.

Specifically, in step S210, the plasma gas is adapted according to the ceramic characteristics, and is adapted for the ceramic substrate to be roughened based on the common component oxide of the ceramic substrate due to the different reaction rates of the plasma gas and the different oxides. For example, the chemical bond energy of oxide is lower, the chemical reaction rate with halogen corrosive gas is faster, the chemical reaction rate of Al-O with higher relative chemical bond energy with halogen corrosive gas is slower, the bond energy of the rest Ca-O is higher, the chemical reaction rate with halogen corrosive gas is slower, etc. Therefore, the corresponding plasma gas is adapted according to the ceramic characteristics, so that the active plasma corresponding to the plasma gas reacts with the target oxide rapidly, and part of volatile reaction products are treated cleanly through vacuum adsorption.

Further, in step S210, after the plasma gas is adapted to the ceramic characteristics, the ceramic substrate having an initial roughness is filled with the plasma gas. In some embodiments, the ceramic substrate to be roughened is smooth with an initial roughness of <0.05um.

On the basis, by controlling the concentration of the plasma and the processing time, the different reaction gas components are efficiently and stably realized, and the ceramic coarsening is safely and conveniently carried out.

The ceramic substrate is placed in the plasma equipment, so that the reaction gas, namely, the plasma gas fills the cavity, plasma gases with different components are adapted according to the characteristics of the ceramic in step S220, the reaction between the plasma and the target oxide in the ceramic substrate is facilitated by adjusting the process parameters and the like, the reaction rates of the active plasma and different oxidation components in the ceramic substrate are different, the micro-etching degree of the plasma and the partial group of the target component in the ceramic substrate is controlled to be high, the reaction product has volatility, the micro-etching degree of the other tissues is lower or the reaction product is not corroded at all. Therefore, by adjusting the reaction technological parameters in the plasma equipment, the plasma ionized by the plasma gas reacts with the target component in the ceramic substrate, so that the surface of the ceramic substrate with initial roughness is reacted to form cellular micropore morphology on the surface of the ceramic substrate, and the ceramic substrate with target roughness, such as the target roughness of about 0.4um, is obtained, and the effect of roughening the ceramic is achieved.

The surface effect of the pre-processed ceramic substrate as exemplified by a in fig. 3 is low in roughness. In fig. 3, B illustrates the surface effect of the ceramic substrate after the treatment according to the present invention, and the improvement effect of the roughness is remarkable compared with the front-rear roughness.

In some embodiments, the ceramic substrate includes a crystalline phase, a glass phase, and a small number of pores.

Common Low Temperature Cofired Ceramic Substrates (LTCCs), typically are composites of crystals and glass. Ceramic substrate compositions are typically multi-phase structures including crystalline phases, glassy phases, and small amounts of gases.

Wherein, the microcrystalline glass system: microcrystalline glass is a composite of a large number of tiny crystals and a small amount of residual glass phase, which is made from a glass of a certain composition by controlled crystallization.

In some embodiments, the ceramic system includes, but is not limited to, silicate-based, aluminosilicate-based, borosilicate-based, borate-based, phosphate-based, and the like. Specifically, glass ceramics are generally classified into five categories, i.e., silicate system, aluminosilicate system, borosilicate system, borate system, and phosphate system, depending on the composition of the base glass.

For example CaO-B ₂ O ₃ -SiO ₂ The LTCC ceramic substrate generally contains CaO and SiO ₂ 、B ₂ O ₃ 、Al ₂ O ₃ Oxides such as MgO, and the like, and crystal phases such as wollastonite, calcium borosilicate, quartz, and the like, and small amounts of pores are formed in the glass phase by liquid phase sintering.

Wherein, glass+ceramic composite system: the glass phase with low melting point is added into the ceramic, and the glass is softened and the viscosity is reduced during sintering, so that the sintering temperature can be reduced. The glass is mainly various crystallized glass, and the ceramic filling phase is mainly Al2O3, siO2, cordierite, mullite and the like.

For another example, the alumina-based LTCC ceramic substrate is formed by adding a low-melting glass phase to an alumina ceramic and sintering the glass, which is generally crystallized glass, and other crystal phases and residual glass phases are precipitated during sintering.

In some embodiments, different ceramic properties are configured with different compositions of plasma gases, including fluorine-containing gases, chlorine-containing gases, and other halogen gases. Including but not limited to carbon tetrafluoride, sulfur hexafluoride, octafluoropropane, chloroform, tetrachlorosilane, hydrogen bromide, boron trichloride, carbon tetrachloride, chlorine.

In the examples of the present specification, caO-B is used as an example ₂ O ₃ -SiO ₂ The LTCC ceramic substrate is provided with carbon tetrafluoride. As another example, an alumina-based LTCC ceramic substrate is provided with carbon tetrafluoride and chlorine. See in particular the detailed description below.

In some embodiments, the reactive plasma has a different reaction rate and reactant phase than the pores, glass phase, crystalline phase in the ceramic substrate.

Specifically, the plasma gas ionizes active plasmas, and the active plasmas respectively have different reaction rates and reactant phases with pores, glass phases and crystalline phases in the ceramic substrate. When reacting with the microcrystalline stripping type LTCC ceramic substrate, CF4 is preferentially etched with the open pores on the surface of the ceramic substrate and the glass phase in the substrate to form a preliminary microetching state; then CF4 and the glass phase are etched, and part of grain boundaries are etched to loosen grains to form a micro-time state; and then CF4 ionizes F and Si-O with lower bond energy in the ceramic component reacts to decompose the F and the Si-O to generate SiF gas. For example, when reacting with the glass+ceramic composite LTCC ceramic substrate, CF4 preferentially etches with the open pores on the surface of the ceramic substrate and the glass phase in the substrate, and then after etching the CF4 with the glass phase on the surface, the internal crystal phases are etched and loosened.

In some embodiments, the ceramic roughening method further comprises: and adjusting the process sequence and the inlet times of each component in the plasma gas.

In combination with the above embodiments, some embodiments include a plasma gas composition including CF4, and other embodiments include a plasma gas composition including CF4 and Cl2. Specifically, for example, when reacting with a microcrystalline glass LTCC ceramic substrate, a plasma gas component is CF4, and CF4 is introduced once during the reaction, so that the open pores on the surface of the ceramic substrate and the glass phase in the substrate are etched preferentially; after the etched surface is cleaned, CF4 is continuously introduced to form a microetching state; and then CF4 is introduced, the CF4 ionizes out active plasmas, and Si-O with lower bond energy in the ceramic component reacts to decompose the active plasmas to generate SiF gas, and the SiF gas is pumped away by a vacuum system, so that the surface of the substrate is roughened to a low degree. And cleaning the etched surface, continuously introducing CF4 to continuously react with the residual Si-O on the ceramic surface, and achieving the state that the surface Si is removed cleanly. Therefore, CF4 is introduced for multiple times in the reaction process to gradually react with the ceramic components, and finally the whole surface of the ceramic substrate is in a honeycomb micropore structure.

For another example, when reacting with the glass+ceramic composite LTCC ceramic substrate, CF4 is introduced first, and the open pores on the surface of the ceramic substrate and the glass phase in the substrate are etched preferentially; after the etched surface is cleaned, CF4 is continuously introduced, after the glass phase of the surface is etched, the internal crystal phases are etched and loosened, and then the etched surface is cleaned, CF4 is closed, cl2 is introduced, so that the Cl2 is ionized to form various neutral groups or Cl ^- Then Cl ^- Continuously reacting with Al-O in the ceramic component to decompose the Al-O to generate AlCl gas, and pumping away the AlCl gas by a vacuum system, wherein the surface of the substrate forms low-level coarsening, and continuously introducing Cl2 after cleaning the etched surface to continuously react with the Al-O in the ceramic component to decompose the Al-O to generate AlCl gas; the alumina target grains on the surface of the final ceramic substrate are etched, while the remaining grains are not etched. Therefore, in the reaction process, CF4 is introduced for a plurality of times, cl2 is gradually introduced to react with the ceramic components, and finally the whole surface of the ceramic substrate is in a honeycomb micropore structure.

In some embodiments adjusting the process parameters includes at least one of: adjusting the concentration of the plasma gas; regulating the pressure of the plasma gas; adjusting the process sequence of each component in the plasma gas; adjusting the times of the introduction of the plasma gas; adjusting the reaction voltage; the reaction time was adjusted.

In combination with the above embodiment, for example, when reacting with a glass ceramic LTCC ceramic substrate, after the ceramic substrate is placed on a reaction platform and vacuumized, 10-100sccm of CF4 is introduced, and the pressure is stabilized to 3Pa, a glow starting voltage is input, about 50V, and the treatment time is 5min; forming a preliminary etching state on the surface of the ceramic; after the etched surface is cleaned, continuously introducing 10-100sccm CF4, stabilizing the pressure to 3Pa, inputting a starting voltage of about 80V, and treating for 15min; so that grain boundary corrosion is easy to generate in the plasma etching process; cleaning the etched surface to form a microetching state; then continuously introducing 10-100sccm CF4, stabilizing the pressure to 3Pa, inputting a starting voltage of about 100-150V, and treating for 15min; forming low-level coarsening on the surface of the substrate; cleaning the etched surface; introducing 100-150sccm of CF4, stabilizing the pressure to 5Pa, and then inputting a starting voltage of about 300V to enable F ions to continuously react with residual Si-O on the surface of the ceramic, so that the surface Si is completely removed; cleaning the etched surface; finally, the silicon dioxide target crystal grains on the surface are etched, and the rest crystal grains are not etched, so that the coarsening purpose is achieved.

When the ceramic substrate reacts with the glass+ceramic composite LTCC ceramic substrate, after the ceramic substrate is placed in a reaction platform to vacuumize equipment, 10-100sccm CF4 is introduced, the pressure is stabilized to 3Pa, and then the starting voltage is input to about 50V for 5min; forming a preliminary microetching state on the surface of the ceramic; after the etched surface is cleaned, continuously introducing 50-100sccm CF4, stabilizing the pressure to 3Pa, inputting a starting voltage of about 80V, and processing for 15min; after the glass phase on the surface of the ceramic is etched, the internal crystal phases are etched and loosened; continuously cleaning the etched surface to form a microetching state, closing CF4 air inlet, introducing 100-150sccm Cl2, stabilizing the pressure to 5Pa, and then inputting a starting voltage of about 100-150V to form low-level roughening on the surface of the ceramic substrate; after the etched surface is cleaned, 150-200sccm Cl2 is continuously introduced and stabilized to 5Pa, and then a starting voltage of about 300V is input, so that the Cl2 continuously reacts with Al-O in the ceramic component to decompose the Al-O to generate AlCl gas; finally, the alumina target grains on the surface of the ceramic are etched, and the rest grains are not etched, so that the coarsening purpose is achieved.

Therefore, the plasma gas reaction concentration to the ceramic substrate is 10-100sccm, 50-100sccm, 100-150sccm, 150-200sccm, and the plasma gas pressure is stabilized at 3Pa or 5Pa, respectively.

In some embodiments, adjusting the process sequence of the plasma gas components includes separately introducing carbon tetrafluoride and chlorine gas into the plasma apparatus, with the carbon tetrafluoride being introduced prior to the chlorine gas.

In combination with the above embodiment, CF4 was introduced multiple times when the plasma gas reacted with the glass-ceramic LTCC ceramic substrate. When the plasma gas reacts with the glass+ceramic composite LTCC ceramic substrate, the components of the plasma gas comprise CF4 and Cl2, and the CF4 and the Cl2 are respectively introduced in the reaction process, for example, the CF4 is introduced for 2 times, for example, the first time is 5min, the second time is 15min, the Cl2 is introduced for two times, the Cl2 is introduced for 100-150sccm, the pressure is stabilized to 5Pa, and the Cl2 is introduced for 150-200sccm, and the pressure is stabilized to 5Pa.

In some embodiments the reaction voltage is adjusted to 10V-500V, such as 100V-150V, 300V; the reaction time is 10 min-30 min, such as 15 min-30 min. The reaction concentration of the plasma gas is 10-200sccm, such as 10-100sccm, 50-100sccm, 100-150sccm, 150-200sccm, etc.

In some embodiments, the ceramic roughening method further comprises: the surface of the ceramic substrate is cleaned by ultrasonic pure water or acetone ultrasonic cleaning.

Specifically, ultrasonic pure water washing or acetone ultrasonic washing is adopted after each reaction stage in the ceramic substrate reaction process.

In connection with the above embodiments, a detailed description of the reaction of plasma gases with different LTCC ceramic substrates is as follows:

example 1: glass ceramic LTCC ceramic substrate

CaO-B ₂ O ₃ -SiO ₂ The LTCC ceramic substrate generally contains CaO and SiO ₂ 、B ₂ O ₃ 、Al ₂ O ₃ Oxides such as MgO, and the like, and crystal phases such as wollastonite, calcium borosilicate, quartz, and the like, and small amounts of pores are formed in the glass phase by liquid phase sintering.

Step1: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, and surface decontamination treatment is carried out;

step2: placing the sample on a reaction platform, vacuumizing the equipment to 10e ^-3 Under Pa, then 40sccmCF4 is introduced and stabilized to 3Pa, then start is introducedGlow voltage, about 50V, treatment time 5min; in plasma etching, the open pores on the surface of the ceramic substrate and the glass phase in the substrate are etched preferentially; at this time, the ceramic surface is in a state of preliminary microetching;

step3: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, and the etched surface is washed;

step3: then, continuously introducing 40sccm CF4, stabilizing the pressure to 3Pa, inputting a starting voltage of about 80V, and processing for 15min; the CBS microcrystalline glass belongs to polycrystalline ceramics, and a plurality of defects exist at the crystal boundary between silicon dioxide crystals and wollastonite crystals as well as between the silicon dioxide crystals and the calcium-boron stone crystals, so that the crystal boundary corrosion is easy to generate in the plasma etching process;

step4: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, the etched surface is washed, at the moment, the glass phase on the surface is etched, and part of grain boundaries are etched to enable inter-grain loosening, so that a microetching state is formed;

step5: then, continuously introducing 40sccm CF4, stabilizing the pressure to 3Pa, inputting a starting voltage of about 100-150V, and treating for 15min; CF4 is ionized to form various neutral groups or ions CF ^4- 、CF ₃ 、CF ₂ CF, C, F, then F reacts with si—o having a lower bond energy in the ceramic component to decompose it to form SiF gas, which is pumped away by a vacuum system (see fig. 1), at which time the substrate surface forms a low level of roughening;

F ⁺ +SiO→SiF (1)

step6: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, and the etched surface is washed;

step7: introducing 100sccm of CF4, stabilizing the pressure to 5Pa, and then inputting a starting voltage of about 300V to enable F ions to continuously react with residual Si-O on the surface of the ceramic, so that the surface Si is completely removed;

step8: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, and the etched surface is washed; finally, the silicon dioxide target crystal grains on the surface are etched, and the rest crystal grains are not etched, so that the coarsening purpose is achieved.

Example 2: glass-ceramic composite LTCC ceramic substrate

The alumina-based LTCC ceramic substrate is formed by adding a low-melting glass phase into alumina ceramic for sintering, wherein the glass is generally crystallized glass, and other crystal phases and residual glass phases can be separated out during sintering.

step2: placing a sample on a reaction platform, vacuumizing the equipment to below 10e-3Pa, then introducing 65sccm CF4, stabilizing the pressure to 3Pa, then inputting a starting voltage of about 50V, and treating for 5min; in plasma etching, the open pores on the surface of the ceramic substrate and the glass phase in the substrate are etched preferentially; at this time, the ceramic surface is in a state of preliminary microetching;

step4: then, continuously introducing 80sccm CF4, stabilizing the pressure to 3Pa, inputting a starting voltage of about 80V, and treating for 15min; the Al2O 3-based LTCC ceramic substrate is mainly an alumina crystal phase, and other small precipitated crystal phases and residual glass phases exist, so that the substrate belongs to multiphase composite ceramics. After the glass phase on the surface is etched, the internal crystal phases are etched and loosened;

step5: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, the etched surface is washed, at the moment, the glass phase on the surface is etched, and part of grain boundaries are etched to enable inter-grain loosening, so that a microetching state is formed;

step6: closing CF4 gas inlet, introducing 120sccm Cl2, stabilizing to 5Pa, inputting glow starting voltage of about 100-150V to ionize Cl2 to form various neutral groups or Cl ^- Then Cl ^- Continuously reacting with Al-O in the ceramic component to decompose the ceramic component into AlCl gas and pumping the AlCl gas by a vacuum system, and at the moment, forming low-level coarsening on the surface of the substrate;

Cl+AlO→AlCl (2)

step7: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, and the etched surface is washed;

step8: continuously introducing 180sccm Cl2, stabilizing the pressure to 5Pa, and then inputting a starting voltage of about 300V to ensure that the Cl2 continuously reacts with Al-O in the ceramic component to decompose to generate AlCl gas;

step9: ultrasonic pure water washing or acetone ultrasonic washing is adopted on the surface of the ceramic substrate for 15min, and the etched surface is washed; finally, the alumina target grains on the surface are etched, and the rest grains are not etched, so that the coarsening purpose is achieved.

In summary, the above embodiment specifically includes: pretreatment, oil stain and polishing solution residue cleaning, placing a ceramic substrate in a cavity of a host machine and vacuumizing, injecting carbon tetrafluoride, starting a radio frequency power supply by equipment, starting an ionization reaction, forming a microetching state with the ceramic substrate, starting a special carbon tetrafluoride or chlorine procedure by the host machine to automatically inject gas into the cavity, heating the equipment to a specified working temperature, starting the radio frequency power supply by the equipment, starting the ionization reaction, ionizing out F, CL plasma with activity to perform surface roughening reaction, finishing the surface treatment of the ceramic substrate, and ending the procedure to pump the substrate out of the equipment.

The surface reaction flow of the ceramic substrate comprises the following steps: gas-ionization of active particles-diffusion and adsorption to the surface to be roughened-surface diffusion-reaction with surface film-desorption of the product-leaving the surface of the ceramic substrate and exhausting the chamber.

According to the embodiment of the specification, carbon tetrafluoride and chlorine are adopted as plasma reaction gases to achieve a remarkable surface roughening effect of the ceramic substrate, and compared with hydrogen fluoride or sulfuric acid in the prior art, the ceramic substrate has high safety and operability by combining the design of the pressure reducing valve. Specifically, a substrate with initial roughness is placed in a main machine cavity of plasma equipment, the flow rate of carbon tetrafluoride injection is 10-100sccm, the treatment time is 5-30min, and the pressure is stabilized to 3Pa.

In connection with the above embodiments, the plasma device for ceramic roughening applications is connected to a storage container storing a plasma gas. A pressure reducing valve is arranged between the plasma equipment and the storage container and is used for adjusting the concentration of the plasma gas input into the plasma equipment from the storage container. When the device is applied, the adaptive high-pressure bottle is used as a storage container, the adaptive pressure reducing valve is used for adjusting the gas concentration of the input plasma equipment, and the reactant gas is introduced in a convenient and safe mode, so that the device has high safety and operability.

The same and similar parts of the embodiments in this specification are all referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the product embodiments described later, since they correspond to the methods, the description is relatively simple, and reference is made to the description of parts of the system embodiments.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions easily conceivable by those skilled in the art within the technical scope of the present application should be covered in the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of coarsening ceramic, the method comprising:

2. The ceramic roughening method of claim 1 wherein different ceramic properties are provided with plasma gases of different composition, the plasma gases comprising at least one of: carbon tetrafluoride, sulfur hexafluoride, octafluoropropane, chloroform, tetrachlorosilane, hydrogen bromide, boron trichloride, carbon tetrachloride and chlorine.

3. The method of claim 1, wherein the ceramic substrate comprises a crystalline phase, a glass phase, and a plurality of pores.

4. The method of claim 1, wherein the reactive plasma has a different reaction rate and a different reactant phase from the pores, the glass phase, and the crystal phase of the ceramic substrate, respectively.

5. The ceramic roughening method according to claim 1, characterized in that the ceramic roughening method further comprises:

and adjusting the process sequence and the inlet times of each component in the plasma gas.

6. The method of claim 5, wherein adjusting the process parameters comprises at least one of:

adjusting the concentration of the plasma gas;

regulating the pressure of the plasma gas;

adjusting the process sequence of each component in the plasma gas;

adjusting the times of the introduction of the plasma gas;

adjusting the reaction voltage;

the reaction time was adjusted.

7. The method of claim 5, wherein adjusting the process sequence of the plasma gas components comprises separately introducing carbon tetrafluoride and chlorine gas into the plasma apparatus, and the carbon tetrafluoride is introduced prior to the chlorine gas.

8. The method for coarsening ceramics according to claim 7, wherein the reaction voltage is adjusted to 10V to 500V; the reaction time is 10-30 min; the reaction concentration of the plasma gas is 10-200sccm.

9. The ceramic roughening method of claim 1 wherein the ceramic system comprises one or more of the following: silicate, aluminosilicate, borosilicate, borate, and phosphate.

10. The ceramic roughening method according to any one of claims 1 to 9, further comprising:

the surface of the ceramic substrate is cleaned by ultrasonic pure water or acetone ultrasonic cleaning.