TWI828146B - Cleaning method for ceramic parts - Google Patents

Abstract

A cleaning method for ceramic parts, which comprises: a first cleaning process, using a chemical solution to dissolve particles on the ceramic parts; In the second cleaning process, the specified acidic solution is used to soften and corrode the particles on the ceramic parts and eliminate the damage layer on the ceramic parts; In the third cleaning process, the ceramic parts are cleaned by ultrasonic cleaning to remove the residual particles and solutions on the ceramic parts. The ceramic parts cleaning method provided by the embodiment of the invention can effectively remove the suspended particles and damage layer on the ceramic parts, so as to solve the problem that the number of ceramic particles exceeds the standard and improve the chip yield.

Description

Ceramic parts cleaning method

The present invention relates to the field of semiconductor manufacturing, and in particular, to a method for cleaning ceramic parts.

As the foundation and core of the information industry, integrated circuits are a global strategic industry related to the national economy and social development. Due to the small size of trenches and line widths in integrated circuits, tiny particles can cause great damage to the process results of wafers (such as silicon wafers). The problem of particle contamination has seriously restricted the extension of the integrated circuit field to lower technology nodes. . Particle control capability is also an important indicator to measure the stability of equipment and process in integrated circuit manufacturing. Especially in the current advanced manufacturing process, the requirements for particle control are getting higher and higher, which puts forward the requirements for integrated circuit equipment. A bigger challenge.

Alumina ceramics is a ceramic material based on aluminum oxide (Al2O3). It is the most stable substance among oxides and has high temperature resistance, corrosion resistance, wear resistance, high mechanical strength, high hardness, high electrical insulation and dielectric properties. The advantages of low loss make alumina ceramic materials increasingly used in semiconductor equipment. However, during the molding process of granulation, sintering and machining, this material will inevitably produce some powdery particles on the surface. Once these particles fall on the wafer during the semiconductor preparation process, they may affect Process results, such as conduction of different wires, disconnection of the same wire, formation of holes, resulting in greater energy consumption and heat generation, etc. If these particles are not removed, they will seriously affect the process results and wafer yield.

In order to remove particles on ceramic parts, the ceramic parts need to be cleaned. However, the existing ceramic parts cleaning methods are difficult to clean the ceramic parts. After cleaning, the damaged layer and suspended particles on the ceramic parts still exist, which cannot meet the needs of semiconductor manufacturing. The manufacturing process requires the number of particles on ceramic parts.

The present invention aims to solve at least one of the technical problems existing in the prior art. It proposes a method for cleaning ceramic parts, which can effectively remove suspended particles and damaged layers on ceramic parts, thereby solving the problem of excessive number of ceramic particles and improving wafer quality. Yield.

In order to achieve the purpose of the present invention, a method for cleaning ceramic parts is provided, which includes: a first cleaning process, using a chemical solution to dissolve particles on the ceramic parts; a second cleaning process, using a designated acidic solution to soften and corrode the particles on the ceramic parts; Eliminate the damaged layer on the ceramic piece; in the third cleaning process, use ultrasonic cleaning to clean the ceramic piece to remove residual particles and solution on the ceramic piece.

Optionally, the specified acidic solution includes a fluorine nitric acid solution, which is a mixture of hydrofluoric acid solution, nitric acid solution and pure water.

Optionally, the ratio of the hydrofluoric acid solution, nitric acid solution and pure water with a resistivity of 18 MΩ·cm is 1:1:1; wherein the hydrofluoric acid solution contains a mass fraction of hydrofluoric acid The range is greater than or equal to 5% and less than or equal to 15%; the range of the mass fraction of nitric acid contained in the nitric acid solution is greater than or equal to 25% and less than or equal to 35%.

Optionally, before performing the third cleaning process, the second cleaning process is performed at least 4 times.

Optionally, the second cleaning process specifically includes the following steps: S21. Rinse the ceramic piece with the specified acidic solution; S22. Soak the ceramic piece rinsed with the specified acidic solution in the specified acidic solution. in the specified acidic solution; S23. Use pure water to rinse the soaked ceramic pieces; S24. Use a grinding tool made of nanomaterials to wipe the ceramic pieces rinsed with pure water; S25. Clean the wiped ceramic pieces. The ceramic parts are soaked in deionized water and ultrasonic cleaned; S26, use pure water to rinse the ceramic parts after ultrasonic cleaning.

Optionally, in step S21, the ceramic piece is rinsed with the designated acidic solution at least 3 times; in step S22, the ceramic piece rinsed with the designated acidic solution is soaked in the The range of the soaking time in the specified acidic solution is greater than or equal to 10 minutes and less than or equal to 20 minutes; in the step S23, use pure water to rinse the soaked ceramic piece 3 to 5 times; in the step S24, use The polishing tool made of nanomaterials wipes the ceramic piece washed with pure water 3 to 5 times; in the step S25, the range of cleaning time for ultrasonic cleaning is greater than or equal to 15 minutes and less than or equal to 30 minutes; the steps In S26, the range of time for rinsing the ceramic piece after ultrasonic cleaning with pure water is greater than or equal to 15 minutes and less than or equal to 60 minutes.

Optionally, the first cleaning process specifically includes the following steps: S11, wipe the ceramic piece with a lint-free cloth moistened with isopropyltone solution; S12, soak the wiped ceramic piece in an alkaline solution. And perform ultrasonic cleaning; S13, use pure water to rinse the ceramic parts after ultrasonic cleaning; S14, soak the rinsed ceramic parts in an acidic solution; S15, use pure water to rinse the ceramic parts after immersing in the acidic solution Rinse the ceramic piece; S16. Soak the rinsed ceramic piece in an alkaline solution.

Optionally, the purity of the isopropyl ketone solution is 99.7%; the alkaline solution is a KOH solution with a concentration percentage range of greater than or equal to 15% and less than or equal to 20%; the temperature range of the alkaline solution is Greater than or equal to 75°C and less than or equal to 85°C; in step S12, the time range for ultrasonic cleaning is greater than or equal to 1 hour and less than or equal to 3 hours; in step S13, pure water is used to clean the ultrasonic cleaning product Rinse the ceramic pieces 3 to 5 times; in the step S14, the soaking time of the rinsed ceramic pieces in the acidic solution ranges from 5 minutes to 10 minutes; in the step S15, use Pure water rinses the ceramic piece after being soaked in the acidic solution 3 to 5 times; in step S16, the range of the soaking time of the rinsed ceramic piece in the alkaline solution is greater than or equal to 1 hour , and less than or equal to 3h.

Optionally, the third cleaning process specifically includes the following steps: S31. Rinse the ceramic parts with pure water; S32. Soak the rinsed ceramic parts in deionized water and perform ultrasonic cleaning; S33. Soak the ultrasonically cleaned ceramic pieces in deionized water. During the soaking process, always introduce new deionized water into the cleaning tank, and use overflow to discharge the deionized water in the cleaning tank; S34. Purge the soaked ceramic piece, and bake the ceramic piece after purging.

Optionally, in step S31, the range of flushing time is greater than or equal to 45 minutes and less than or equal to 60 minutes; in step S32, the range of ultrasonic cleaning time is greater than or equal to 30 minutes and less than or equal to 60 minutes; the steps In S33, the soaking time range is greater than or equal to 30 minutes and less than or equal to 60 minutes; in the step S33, the temperature maintenance range of the deionized water is greater than or equal to 32°C and less than or equal to 42°C; in the step S34 , the purge gas used includes nitrogen, the purity of the nitrogen is 99.999%; the range of the angle between the purge direction of the nitrogen and the surface of the ceramic piece is greater than or equal to 30°C and less than or equal to 45°C.

Optionally, the ceramic part includes a ceramic process kit for semiconductor equipment.

The invention has the following beneficial effects:

The ceramic parts cleaning method provided by the embodiment of the present invention divides the cleaning into three cleaning processes. The first cleaning process uses a chemical solution to dissolve particles on the ceramic parts. This process can effectively remove larger particles on the surface of the ceramic parts. The particles in blind holes, wrinkles and non-welded gaps are cleaned; the second cleaning process uses designated acidic solutions to soften the particles on the corroded ceramic parts and eliminate the damaged layer on the ceramic parts, because the existence of this damaged layer is an important source of particle generation. One, the above-mentioned second cleaning process uses the above-mentioned designated acidic solution to eliminate the damaged layer on the ceramic parts in a targeted manner, which can effectively remove particles at the source, which can greatly reduce the number of particles compared with the existing technology; the third cleaning process Ultrasonic cleaning is used to clean ceramic parts to remove residual particles and solutions (acidic or alkaline solutions) on the ceramic parts, so that the ceramic parts can be fully cleaned, which can ultimately effectively improve the cleaning effect and solve the problem of excessive number of ceramic particles. , improve wafer yield.

The following disclosure provides many different embodiments or examples of different means for implementing the disclosure. Specific examples of components and configurations are described below to simplify the present disclosure. Of course, these are examples only and are not intended to be limiting. For example, the following description in which a first member is formed over or on a second member may include embodiments in which the first member and the second member are formed in direct contact, and may also include embodiments in which additional members Embodiments may be formed between the first member and the second member such that the first member and the second member may not be in direct contact. Additionally, the present disclosure may repeat reference numbers and/or letters in various instances. This repetition is for simplicity and clarity and does not inherently indicate a relationship between the various embodiments and/or configurations discussed.

In addition, for ease of description, spatially relative terms such as “below,” “below,” “lower,” “above,” “upper,” and the like may be used herein to describe one element or component in relation to another(s). The relationship between components or components, as illustrated in the figure. Spatially relative terms are intended to cover different orientations of the device in use or operation other than the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the values stated in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Furthermore, as used herein, the term "about" generally means within 10%, 5%, 1% or 0.5% of a given value or range. Alternatively, the term "approximately" means within one acceptable standard error of the mean when considered by one of ordinary skill in the art. Except in operating/working examples, or unless otherwise expressly specified, all numerical ranges such as quantities, durations of time, temperatures, operating conditions, ratios of quantities, and the like for materials disclosed herein, Quantities, values and percentages should be understood to be modified in all instances by the term "approximately". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the patent claims of this disclosure and accompanying invention claims are approximations that may vary as necessary. At a minimum, each numerical parameter should be interpreted in light of the number of reported significant digits and by applying ordinary rounding techniques. Ranges may be expressed herein as from one endpoint to the other endpoint or between two endpoints. All ranges disclosed herein include endpoints unless otherwise specified.

Embodiments of the present invention provide a method for cleaning ceramic parts, which can be applied to cleaning ceramic parts such as process kits, ceramic covers, and ceramic layers of electrostatic chucks in process chambers in semiconductor equipment.

Specifically, please refer to Figure 1. Ceramic parts cleaning methods include:

In the first cleaning process S1, a chemical solution is used to dissolve particles on the ceramic parts;

The first cleaning process S1 can effectively clean particles on the surface of ceramic parts, especially particles in large blind holes, wrinkles and non-welding gaps on the surface of ceramic parts.

The second cleaning process S2 uses a designated acidic solution to soften the particles on the corroded ceramic parts and eliminate the damaged layer on the ceramic parts;

Since the existence of this damaged layer is one of the important sources of particle generation, the above-mentioned second cleaning process S2 uses the above-mentioned specified acid solution to eliminate the damaged layer on the ceramic parts in a targeted manner, which can effectively remove particles at the source, which is consistent with the existing technology. In comparison, the number of particles can be greatly reduced.

In the third cleaning process S3, ultrasonic cleaning is used to clean the ceramic parts to remove residual particles and solution on the ceramic parts.

The so-called ultrasonic cleaning refers to cleaning particles on ceramic parts through water waves generated by ultrasonic vibration. The third cleaning process S3 can comprehensively clean the ceramic parts to remove residual particles and solutions (acidic or alkaline solutions) on the ceramic parts, which can ultimately effectively improve the cleaning effect.

Specifically, in the above-mentioned second cleaning process S2, the designated acidic solution includes a fluorine nitric acid solution, which is a mixture of hydrofluoric acid solution, nitric acid solution and pure water, which can soften the particles on the corroded ceramic parts and eliminate the corrosion of the ceramics. Damage layer on the part. Of course, in practical applications, any other acidic solution that can play the same role can also be used.

In order to strengthen the softening and elimination effect of the above-mentioned hydrofluoric acid solution on the damaged layer on the ceramic parts, optionally, the ratio of the above-mentioned hydrofluoric acid solution, nitric acid solution and pure water with a resistivity of 18MΩ·cm is 1:1:1 ; Among them, the range of the mass fraction of hydrofluoric acid contained in the hydrofluoric acid solution is greater than or equal to 5% and less than or equal to 15%; the range of the mass fraction of nitric acid contained in the nitric acid solution is greater than or equal to 25% and less than or equal to 35%. .

In order to enhance the above-mentioned softening and elimination effect on the damaged layer on the ceramic piece, optionally, before performing the third cleaning process S3, the above-mentioned second cleaning process S2 is performed at least 4 times.

The specific implementation of the above second cleaning process S2 will be described in detail below. Specifically, as shown in Figure 2, the second cleaning process S2 specifically includes the following steps:

S21. Use the above specified acid solution to rinse the ceramic parts;

Optionally, in step S21, use the specified acidic solution to rinse the ceramic piece at least 3 times.

S22. Soak the ceramic pieces rinsed with the above specified acidic solution in the above specified acidic solution;

Optionally, in the above step S22, the soaking time range of the ceramic piece rinsed with the designated acidic solution in the designated acidic solution is greater than or equal to 10 minutes and less than or equal to 20 minutes.

S23. Use pure water to rinse the soaked ceramic parts;

Optionally, in the above step S23, pure water is used to rinse the soaked ceramic piece 3 to 5 times.

S24. Use a grinding tool made of nanomaterials to wipe the ceramic parts after being rinsed with pure water;

Optionally, in the above step S24, a polishing tool made of nanomaterials is used to wipe the ceramic piece washed with pure water 3 to 5 times.

S25. Soak the wiped ceramic parts in deionized water and perform ultrasonic cleaning;

Optionally, in the above step S25, the range of cleaning time for ultrasonic cleaning is greater than or equal to 15 minutes and less than or equal to 30 minutes.

S26. Use pure water to rinse the ceramic parts after ultrasonic cleaning.

Optionally, in the above step S26, the time for rinsing the ceramic piece after ultrasonic cleaning with pure water is greater than or equal to 15 minutes and less than or equal to 60 minutes.

The specific implementation of the above-mentioned first cleaning process S1 will be described in detail below. Specifically, as shown in Figure 3, the first cleaning process S1 specifically includes the following steps:

S11. Wipe the ceramic parts with a lint-free cloth dipped in isopropyltone (IPA) solution;

The above-mentioned step S11 can conduct electricity to the ceramic piece to neutralize the charged ceramic particles on the ceramic piece.

Optionally, the purity of the above-mentioned isopropyl ketone solution is 99.7%.

It should be noted that during the wiping process, if there are stains on the surface of the lint-free cloth, the lint-free cloth needs to be cleaned again to avoid damage to the texture and smooth surface of the ceramic piece.

S12. Soak the wiped ceramic parts in an alkaline solution and perform ultrasonic cleaning;

The alkaline solution (that is, the chemical solution used in the above-mentioned first cleaning process S1) can dissolve the particles on the ceramic piece, and combined with ultrasonic cleaning, the particles can be effectively removed.

In order to effectively dissolve the particles on the ceramic parts and improve the cleaning effect, optionally, the above-mentioned alkaline solution is, for example, a KOH solution with a concentration range of greater than or equal to 15% and less than or equal to 20%, and the temperature range of the alkaline solution is greater than or equal to 75° and less than or equal to 85°; in step S12, the range of ultrasonic cleaning time is greater than or equal to 1 hour and less than or equal to 3 hours. By setting the ultrasonic cleaning time in the above range, the ceramic parts can be effectively dissolved The particles on the ceramic parts can prevent the ceramic parts from being soaked in alkaline solution for too long, which will cause damage to the sealing surface and hole edges of the ceramic parts, affecting the sealing performance of the parts.

In practical applications, a concentration detector can be used to detect the concentration value of the KOH solution, and the solution can be replaced or supplemented according to the detected concentration value to achieve the target concentration value.

S13. Use pure water to rinse the ceramic parts after ultrasonic cleaning;

Optionally, in the above step S13, pure water is used to rinse the ultrasonic cleaned ceramic piece 3 to 5 times.

S14. Soak the rinsed ceramic pieces in acidic solution;

The above-mentioned step S14 can neutralize the alkaline solution remaining on the ceramic piece to reduce corrosion of the ceramic piece by the alkaline solution and avoid damage to the sealing surface and hole edge of the ceramic piece by the alkaline solution.

Optionally, in the above step S14, the soaking time of the rinsed ceramic piece in the acid solution ranges from greater than or equal to 5 minutes to less than or equal to 10 minutes.

Optionally, the above-mentioned acidic solution is hydrochloric acid or fluorine nitric acid solution, wherein the neutralization effect of fluorine nitric acid solution and an alkaline solution (such as KOH solution) is better.

In addition, ultrasonic cleaning may not be used in the above step S14.

S15. Use pure water to rinse the ceramic parts after being soaked in the acidic solution;

S16. Soak the rinsed ceramic pieces in alkaline solution.

The above step S16 can further dissolve the particles on the ceramic piece.

Optionally, in the above step S16, the range of the soaking time for immersing the rinsed ceramic pieces in the alkaline solution is greater than or equal to 1 hour and less than or equal to 3 hours. By setting the soaking time in the above range, the ceramic pieces can be effectively dissolved. The particles on the ceramic parts can prevent the ceramic parts from being soaked in alkaline solution for too long, which will cause damage to the sealing surface and hole edges of the ceramic parts, affecting the sealing performance of the parts.

The specific implementation of the above third cleaning process S3 will be described in detail below. Specifically, as shown in Figure 4, the third cleaning process S3 specifically includes the following steps:

S31. Use pure water to rinse the ceramic parts;

Optionally, in the above step S31, the range of flushing time is greater than or equal to 45 minutes and less than or equal to 60 minutes;

S32. Soak the rinsed ceramic parts in deionized water and perform ultrasonic cleaning;

The above-mentioned step S32 can comprehensively clean the ceramic parts. Since ultrasonic cleaning using deionized water has the most obvious cleaning effect, after completing the ultrasonic cleaning step, it can be ensured that the cleaning effect of the ceramic parts meets the process requirements. Moreover, the damage layer and suspended particles have been removed using the previous first cleaning process S1 and the second cleaning process S2, which can make up for the inability of ultrasonic cleaning to completely remove the damage layer and suspended particles.

Optionally, in the above step S32, the time range for ultrasonic cleaning is greater than or equal to 30 minutes and less than or equal to 60 minutes.

Optionally, the resistivity of the above-mentioned deionized water is greater than or equal to 4MΩ·cm.

S33. Soak the ultrasonically cleaned ceramic parts in deionized water. During the soaking process, always introduce new deionized water into the cleaning tank, and use overflow to discharge the deionized water in the cleaning tank;

In the above step S33, by always introducing new deionized water into the cleaning tank during the soaking process, and using overflow to discharge the deionized water in the cleaning tank, the deionized water can be kept in a circulating flow state. This can further improve the cleaning effect.

Optionally, in the above step S33, the temperature of the deionized water is maintained in a range of greater than or equal to 32°C and less than or equal to 42°C.

S34. Purge the soaked ceramic pieces, and bake the ceramic pieces after purging.

Optionally, the purge gas used in the above step S34 includes nitrogen, and the purity of the nitrogen is 99.999%; the angle between the purge direction of the nitrogen and the surface of the ceramic piece ranges from greater than or equal to 30°C to less than or equal to 45°C. To prevent particles from falling back onto the surface of the ceramic piece.

Optionally, first use dry nitrogen to comprehensively purge the ceramic parts; then use dry nitrogen to purge the purification furnace (or oven) to dry the inside; finally, place the ceramic parts into the purged purification furnace (or oven). Bake in oven).

In the following, a comparative experiment will be conducted on ceramic pieces obtained by using the ceramic piece cleaning method in the prior art and the ceramic piece cleaning method provided by the embodiment of the present invention. Specifically, the process of the ceramic parts cleaning method in the prior art is: first, immerse the ceramic parts in an alkaline degreasing agent for 50min-80min, and then rinse the ceramic parts in deionized water (use pressurized deionized water to spray the ceramics (everywhere on the surface of the piece); after that, immerse the ceramic piece in the acidic solution for 5min-10min, then take the ceramic piece out of the solution and immerse it again in deionized water for the above rinse, and then immerse it in a solution with a resistivity of ≥4MΩ·cm and room temperature. Carry out ultrasonic cleaning in deionized water for 10min-15min, then immerse the ceramic parts in deionized water with a resistivity of ≥8 MΩ·cm and perform hot water soaking. Finally, use nitrogen to blow dry the ceramic parts and dry the ceramic parts to complete the entire cleaning process.

The ceramic parts cleaning method provided by the embodiment of the present invention includes the above three cleaning processes S1-S3, wherein the first cleaning process S1 includes the above steps S11-S16; the second cleaning process S2 includes the above steps S21-S26; and the third cleaning process S3 includes the above steps S31-S34.

Figure 5 is a comparative view of the damaged layer on the ceramic piece obtained by using the ceramic piece cleaning method in the prior art and the ceramic piece cleaning method provided by the embodiment of the present invention. Based on the experimental data and shown in Figure 5, the ceramic parts obtained by using the ceramic parts cleaning method in the prior art still have a machining damage layer on the surface. As shown in (a) of Figure 5, the thickness of the damage layer is 10μm-30μm, and the existence of this damage layer is one of the important sources of particle generation. In contrast, as shown in (b) of Figure 5 , for ceramic parts obtained by using the ceramic parts cleaning method provided by the embodiment of the present invention, the damaged layer on the ceramic parts is significantly removed, thereby avoiding the possibility of damage to the ceramic parts. Particles continue to fall out during use on the device.

Figure 6 is a comparative diagram of suspended particles on ceramic parts obtained by using the ceramic parts cleaning method in the prior art and the ceramic parts cleaning method provided by the embodiment of the present invention. Combining the experimental data and shown in Figure 6, the ceramic parts obtained by using the ceramic parts cleaning method in the prior art still have suspended particles of 0.2 μm ~ 1 μm on the ceramic surface, as shown in (a) of Figure 6. In the figure The white dots on the black area are suspended particles. In addition, the number of particles per unit area that falls on the wafer during the manufacturing process of the ceramic parts obtained by the ceramic parts cleaning method in the prior art is ≥500ea, which is much higher than the particle index (the number of particles per unit area is <2ea). , In addition, the detection value obtained by measuring the liquid particle count (ie, LPC) on the ceramic piece is 75856PA/cm2. In comparison, as can be seen in (b) of Figure 6, the white dots in the black area in the figure are significantly reduced. From this, it can be seen that the ceramic parts obtained by using the ceramic parts cleaning method provided by the embodiment of the present invention , the suspended particles on the ceramic part are significantly reduced. The number of particles per unit area of the ceramic part falling on the wafer during the manufacturing process is lower than the particle index (the number of particles per unit area is <2ea), and its LPC is measured to obtain The detection value is 729PA/cm2, which is far smaller than the above-mentioned LPC detection value of the existing technology.

The ceramic parts in embodiments of the present invention include, for example, ceramic process kits for semiconductor devices. The ceramic process kit can be components made of ceramic materials such as inner linings, media windows, nozzles, screen tubes, main and auxiliary media cylinders of the three-dimensional induction coil, and observation window protection cylinders. By improving the cleaning effect of the above components, the problem of excessive number of ceramic particles can be effectively solved and the wafer yield rate can be improved.

In summary, the ceramic parts cleaning method provided by the embodiment of the present invention divides the cleaning into three cleaning processes. In the first cleaning process, a chemical solution is used to dissolve the particles on the ceramic parts. This process can effectively clean the surface of the ceramic parts. Clean the particles in larger blind holes, wrinkles and non-welding gaps; the second cleaning process uses designated acidic solutions to soften the particles on the corroded ceramic parts and eliminate the damaged layer on the ceramic parts, because the existence of the damaged layer is One of the important sources of particle generation, the above-mentioned second cleaning process uses the above-mentioned designated acidic solution to eliminate the damaged layer on the ceramic parts in a targeted manner, which can effectively remove particles at the source. This can greatly reduce the number of particles compared with the existing technology. ; The third cleaning process uses ultrasonic cleaning to clean ceramic parts to remove residual particles and solutions (acidic or alkaline solutions) on the ceramic parts, so that the ceramic parts can be fully cleaned, which can ultimately effectively improve the cleaning effect and solve the problem of ceramic parts. To solve the problem of excessive number of particles and improve the wafer yield.

The foregoing content summarizes the features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also understand that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they can be variously changed, replaced and modified herein without departing from the spirit and scope of the present disclosure.

S1-S3, S21-S26, S11-S16, S31-S34: steps

The present disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that in accordance with standard practice in the industry, the various components are not drawn to scale. In fact, the dimensions of the various components may be arbitrarily increased or reduced for clarity of discussion. Figure 1 is a flow chart of a method for cleaning ceramic parts provided by an embodiment of the present invention; Figure 2 is a flow chart of the second cleaning process adopted in the embodiment of the present invention; Figure 3 is a flow chart of the first cleaning process adopted in the embodiment of the present invention; Figure 4 is a flow chart of the third cleaning process adopted in the embodiment of the present invention; Figure 5 is a comparative view of the damaged layer on the ceramic piece obtained by using the ceramic piece cleaning method in the prior art and the ceramic piece cleaning method provided by the embodiment of the present invention; Figure 6 is a comparative diagram of suspended particles on ceramic parts obtained by using the ceramic parts cleaning method in the prior art and the ceramic parts cleaning method provided by the embodiment of the present invention.

S1-S3: Steps

Claims (8)

A method for cleaning ceramic pieces, including: a first cleaning process, using a chemical solution to dissolve particles on a ceramic piece; a second cleaning process, using a designated acidic solution to soften and corrode the particles on the ceramic piece and eliminate the particles on the ceramic piece Damage layer; the third cleaning process uses ultrasonic cleaning to clean the ceramic piece to remove residual particles and solution on the ceramic piece; wherein, the first cleaning process, the second cleaning process and the third cleaning process use In order to remove the powdery particles produced on the ceramic parts during the molding process; the first cleaning process specifically includes the following steps: S11, wipe the ceramic parts with a lint-free cloth dipped in isopropyltone solution; S12, wipe the wiped ceramic parts The ceramic parts are soaked in an alkaline solution and subjected to ultrasonic cleaning; S13, use pure water to rinse the ceramic parts after ultrasonic cleaning; S14, soak the rinsed ceramic parts in an acidic solution; S15, use pure water to clean the ceramic parts. Rinse the ceramic piece after being soaked in the acidic solution; S16, soak the rinsed ceramic piece in an alkaline solution; wherein the second cleaning process specifically includes the following steps: S21, use the specified acidic solution to clean the ceramic piece Rinse; S22. Soak the ceramic piece rinsed with the specified acidic solution in the specified acidic solution; S23. Rinse the soaked ceramic piece with pure water; S24. Wipe it with a grinding tool made of nanomaterials. The ceramic after being rinsed with pure water piece; S25, soak the wiped ceramic piece in deionized water and perform ultrasonic cleaning; S26, use pure water to rinse the ultrasonic cleaned ceramic piece; wherein the third cleaning process specifically includes the following steps: S31. Use pure water to rinse the ceramic piece; S32. Soak the rinsed ceramic piece in deionized water and perform ultrasonic cleaning; S33. Soak the ultrasonic cleaned ceramic piece in deionized water. During the soaking process, Always introduce new deionized water into the cleaning tank, and use overflow to discharge the deionized water in the cleaning tank; S34, purge the soaked ceramic piece, and clean the ceramic piece after purging. pieces for baking. The method for cleaning ceramic parts as described in claim 1, wherein the designated acidic solution includes a fluorine nitric acid solution, which is a mixture of hydrofluoric acid solution, nitric acid solution and pure water. The method for cleaning ceramic parts as described in claim 2, wherein the ratio of the hydrofluoric acid solution, nitric acid solution and pure water with a resistivity of 18MΩ.cm is 1:1:1; wherein, the hydrofluoric acid solution contains The mass fraction of hydrofluoric acid ranges from greater than or equal to 5% to less than or equal to 15%; the mass fraction of nitric acid contained in the nitric acid solution ranges from greater than or equal to 25% to less than or equal to 35%. The ceramic piece cleaning method according to any one of claims 1 to 3, wherein the second cleaning process is performed at least 4 times before the third cleaning process is performed. The ceramic piece cleaning method as described in claim 1, wherein in step S21, the ceramic piece is rinsed with the designated acidic solution at least 3 times; in step S22, the ceramic piece washed with the designated acidic solution is soaked The range of the soaking time in the designated acidic solution is greater than or equal to 10 minutes and less than or equal to 20 minutes; in step S23, pure water is used to rinse the soaked ceramic piece 3 to 5 times; in step S24, sodium chloride is used. The polishing tool made of rice material wipes the ceramic piece after being rinsed with pure water 3 to 5 times; in step S25, the cleaning time range of ultrasonic cleaning is greater than or equal to 15 minutes and less than or equal to 30 minutes; in step S26, The time range for rinsing the ceramic piece after ultrasonic cleaning with pure water is greater than or equal to 15 minutes and less than or equal to 60 minutes. The method for cleaning ceramic parts as described in claim 1, wherein the purity of the isopropyl solution is 99.7%; the alkaline solution is a KOH solution with a concentration percentage range of greater than or equal to 15% and less than or equal to 20%, and the alkaline solution The temperature range of the solution is greater than or equal to 75° and less than or equal to 85°; in step S12, the time range for ultrasonic cleaning is greater than or equal to 1h and less than or equal to 3h; in step S13, pure water is used for ultrasonic cleaning The washed ceramic piece is rinsed 3 to 5 times; in step S14, the soaking time range of the rinsed ceramic piece in the acidic solution is greater than or equal to 5 minutes and less than or equal to 10 minutes; in step S15, use Pure water rinses the ceramic piece after being soaked in the acidic solution 3 to 5 times; in step S16, the soaking time of the rinsed ceramic piece in the alkaline solution ranges from greater than or equal to 1 hour to less than or equal to 3h. The method for cleaning ceramic parts as described in claim 1, wherein in step S31, the rinsing time The range is greater than or equal to 45 minutes and less than or equal to 60 minutes; in step S32, the range of ultrasonic cleaning time is greater than or equal to 30 minutes and less than or equal to 60 minutes; in step S33, the range of soaking time is greater than or equal to 30 minutes and less than or equal to 60 minutes. 60 min; in step S33, the temperature of the deionized water is maintained in a range of greater than or equal to 32°C and less than or equal to 42°C; in step S34, the purge gas used includes nitrogen, and the purity of the nitrogen is 99.999%; The range of the angle between the purging direction of the nitrogen gas and the surface of the ceramic piece is greater than or equal to 30° and less than or equal to 45°. The ceramic part cleaning method as claimed in claim 1, wherein the ceramic part includes a ceramic process kit for semiconductor equipment.