TWI700742B - Quartz surface treatment method for quartz surface coating - Google Patents

Abstract

The invention relates to a quartz surface treatment method for coating the surface of quartz, and a method for surface treatment of the quartz used in semiconductor manufacturing equipment before spraying other substances. According to an embodiment of the present invention, the present invention includes: a preparation step of preparing the above-mentioned quartz; a chemical treatment step of performing a chemical treatment by supplying a chemical solution to the surface of the above-mentioned quartz to form embossing on the surface of the above-mentioned quartz; a cleaning step, After the chemical treatment step, the surface of the quartz is cleaned; and the drying step is to dry the surface of the quartz, and in the semiconductor manufacturing process, supply the semiconductor manufacturing equipment used in the plasma etching process or the semiconductor diffusion process. Quartz, the above-mentioned chemical solution includes organic acid and acidic ammonium bifluoride (NH ₄ HF ₂ ). In the above chemical treatment step, the above-mentioned acidic ammonium bifluoride reacts with the surface of the quartz to form part of the surface of the quartz The mask material, and the surface area of the quartz where the mask material is not generated reacts with the organic acid, thereby etching the surface of the quartz.

Description

Quartz surface treatment method for coating quartz surface

The present invention relates to a method of treating the surface of quartz used in semiconductor manufacturing equipment before coating the surface, and more particularly to a method of chemically treating the surface of quartz before spraying the surface of quartz.

Quartz products have high purity (99.999%), chemical stability, acid resistance, heat resistance (softening point temperature of 1683℃), excellent light transmission, low thermal expansion, and excellent electrical insulation, so they can be widely used in semiconductors , Optical communications, electrical and electronic industries.

For example, in the usual silicon wafer processing processes, silicon wafers are processed by processes such as chemical vapor deposition (CVD, Chemical Vapor Deposition), etching, and ashing. In these processes, quartz products are used Support or configure the wafer.

Due to the high temperature above 1000°C applied in the above process, a stress caused by the difference in thermal expansion coefficient between the quartz and the silicon wafer is caused in the part where the wafer is in contact with the quartz surface, and a contact mark can be generated at the contact part of the wafer. ).

In the case where the substance generated during the processing of the silicon wafer adheres to the surface of the quartz material product to form a film, when the quartz material product is cooled after the processing process, due to the difference in the thermal expansion coefficient between the film and the glass However, cracking or breaking can occur in the quartz material product.

Also, when the quartz material product is cooled, if the adhesion state of the substance on the quartz surface is weak, the substance will fall from the quartz surface, but if the roughness of the quartz surface is low, the adhesion state will become stronger. Therefore, the above-mentioned thin film still exists in the subsequent processing of the silicon wafer, and even if the quartz material product does not produce cracks or cracks, particles will be generated before the above-mentioned film falls from the surface.

In order to prevent the generation of contact marks and reduce the contact area on the wafer, sand blasting is performed on the surface of the quartz material product to make the surface of the quartz material product rough and form an uneven sandblasted surface.

In addition, when the sandblasted surface is formed, the stress generated in the cooling step after the silicon wafer is processed on the sandblasted quartz surface is dispersed in all directions, thereby preventing substances adhering to the quartz surface from being cooled. Fall from the above surface.

However, when the sandblasted surface is in contact with the wafer, the silicon dioxide particles are scraped from the above-mentioned wafer, or the silicon dioxide particles are confined to the inside of the sandblasted surface, and in the molding step of the quartz material product, the sandblasting The silicon dioxide particles expand inside the surface area. During the wafer processing, the particles float from the surface and fall onto the patterned wafer surface, so that the sandblasted quartz surface can cause pattern defects.

The size of the generated particles is in the range of 0.2μm to 5μm. Even if the particle size is 0.3μm or a tiny size less than 0.3μm, it can become a serious problem. Especially, in recent years, in the fine semiconductor process, the need For wiring patterns of 0.18 μm or less, in such a fine semiconductor process, preventing the generation of the above-mentioned fine particles is an important issue, otherwise the yield in semiconductor wafer manufacturing may decrease.

That is to say, due to the characteristics of quartz materials, the surface treatment of quartz through the existing sandblasting process is highly brittle, so cracks may occur due to the stress generated during the sandblasting treatment, and sparks may be generated on the surface, making it difficult to manipulate fine sections and shapes. Complex quartz material. In addition, only one product can be processed at a time, so operability and productivity are reduced, and it is difficult to apply to large-sized objects.

In order to solve the above-mentioned problems, the present invention provides a quartz surface treatment method that treats the surface of quartz through a chemical treatment process instead of a sandblasting process.

The present invention is not limited to this, and those skilled in the art can clearly understand other purposes not mentioned from the following description.

The present invention provides a method for surface-treating the surface of quartz used in semiconductor manufacturing equipment before spraying other substances.

According to an embodiment of the present invention, a quartz surface treatment method for coating a quartz surface may include: a preparation step of preparing the above-mentioned quartz; a chemical treatment step of performing chemical treatment by supplying a chemical solution to the surface of the above-mentioned quartz, so as to The surface of the quartz is embossed; the cleaning step is to clean the surface of the quartz after the above chemical treatment step; and the drying step is to dry the surface of the quartz, and in the semiconductor manufacturing process, to the etching process using plasma or semiconductor diffusion The semiconductor manufacturing equipment used in the process supplies the quartz, and the chemical solution contains organic acid and acidic ammonium bifluoride. In the chemical treatment step, the acidic ammonium bifluoride reacts with the surface of the quartz to form part of the surface of the quartz. A mask material is formed in the region, and the surface region of the quartz where the mask material is not formed reacts with the organic acid to etch the surface of the quartz.

According to an embodiment, in the above chemical solution, the composition ratio of the organic acid may be 40% to 70%, and the composition ratio of the acidic ammonium bifluoride may be 5% to 40%.

According to an embodiment, the above-mentioned liquid medicine may be composed of hydrofluoric acid (HF), the above-mentioned acidic ammonium bifluoride, the above-mentioned organic acid and deionized water, and the above-mentioned organic acid may include formic acid and citric acid.

According to an embodiment, in the composition ratio of the chemical solution, the hydrofluoric acid may be 4%, the acidic ammonium bifluoride may be 31%, the formic acid may be 44%, the citric acid may be 4%, and the deionization Water can be 17%.

According to an embodiment, the above chemical treatment step may include: a first surface treatment step, by supplying the chemical solution to the quartz to perform the first treatment on the surface of the quartz; an intermediate cleaning step, in the first surface treatment After the step, the surface of the quartz is cleaned; and the second surface treatment step, after the intermediate cleaning step, the surface of the quartz is treated for the second time by supplying the chemical solution to the quartz.

According to an embodiment, before the chemical treatment step, a preparatory cleaning step of cleaning the surface of the quartz can be further included.

According to an embodiment, the above-mentioned cleaning step and the above-mentioned intermediate cleaning step may be steps of removing the above-mentioned mask material generated on the surface of the above-mentioned quartz.

According to an embodiment, the above-mentioned mask material may be Ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ).

According to an embodiment of the present invention, a predetermined range of surface roughness is formed on the surface of the quartz by the chemical liquid, so that the formation of chips or cracks on the surface can be prevented after spraying. In addition, it can prevent foreign matter from being generated in the semiconductor manufacturing process.

The effects of the present invention are not limited to the above-mentioned effects, and those skilled in the art can clearly understand the unmentioned effects from this specification and the drawings.

11‧‧‧Quartz

13‧‧‧Mask material

15‧‧‧area

S10‧‧‧Preparation steps

S20‧‧‧Prepare cleaning steps

S30‧‧‧Chemical treatment steps

S31‧‧‧First surface treatment step

S32‧‧‧Intermediate cleaning step

S33‧‧‧Second surface treatment step

S40‧‧‧Cleaning steps

S50‧‧‧Drying step

Fig. 1 is a diagram sequentially showing the steps of spraying and manufacturing the surface of quartz.

FIG. 2 is a diagram showing in sequence a method of manufacturing a quartz surface by spraying a process including chemical treatment of the quartz surface according to an embodiment of the present invention.

Fig. 3 is a flowchart showing a quartz surface treatment method for coating a quartz surface in sequence according to an embodiment of the present invention.

4 to 7 are diagrams briefly showing the process of forming embossing on the surface of quartz.

FIG. 8 is a diagram showing a comparison of the surface state of quartz when the surface of the quartz is not processed, when the surface treatment is performed by the sandblasting process, and when the chemical treatment process is used.

Hereinafter, embodiments of the present invention will be described in further detail with reference to the drawings. The embodiments of the present invention can be modified in various forms, and the scope of the present invention should not be construed as being limited to the following multiple embodiments. This embodiment is provided in order to describe the present invention more completely to those skilled in the art. Therefore, the shapes of elements in the drawings may be exaggerated to emphasize a clearer description. In addition, the terms or words used in this specification and the scope of protection of the invention should not be interpreted as being limited to ordinary or dictionary meanings, and the inventor can appropriately define the concept of the term to describe his invention in the best way, and shall be It is explained as meaning and concept conforming to the technical idea of the present invention.

The present invention provides a quartz surface treatment method for coating quartz surface. The present invention relates to quartz 11 supplied to semiconductor manufacturing equipment used in an etching process using plasma or a semiconductor diffusion process in a semiconductor manufacturing process.

The quartz supplied to the above-mentioned semiconductor manufacturing equipment is usually supplied by spraying.

Fig. 1 is a diagram sequentially showing the steps of spraying and manufacturing the surface of quartz.

With reference to this, in the past, before spraying the surface of quartz, a sandblasting process was used for surface treatment. The sandblasting process is a process in which embossing is formed on the surface of quartz through a mechanical process. However, when using the sandblasting process, chips or cracks can be generated on the surface of the quartz.

When chips or cracks are formed on the surface of quartz, even if the surface of quartz is sprayed, foreign matter may be generated during the plasma etching process or the diffusion process, thereby causing problems.

FIG. 2 is a diagram showing in sequence a method of manufacturing a quartz surface by spraying a process including chemical treatment of the quartz surface according to an embodiment of the present invention.

2, in the present invention, the surface of quartz can be chemically treated and then sprayed. After that, it is supplied to semiconductor manufacturing equipment through cleaning and inspection. As an example, quartz may be installed in a part of a chuck supporting a wafer in a semiconductor manufacturing equipment, or may be installed in a window or the like.

Fig. 3 is a flowchart showing in sequence a quartz surface treatment method for coating a quartz surface according to an embodiment of the present invention, and Figs. 4 to 7 are diagrams briefly showing the process of forming embossing on the surface of quartz.

Next, a method of processing the surface of the quartz 11 for semiconductor manufacturing equipment will be described with reference to FIGS. 3 to 7. The quartz surface treatment method includes a preparation step S10, a preparation cleaning step S20, a chemical treatment step S30, a cleaning step S40, and a drying step S50.

The preparation step S10 is a step of preparing the quartz 11.

The preparation cleaning step S20 is a step of cleaning the surface of the quartz 11 prepared in the preparation step S10. As an example, in the preparation cleaning step S20, the surface of the quartz 11 may be cleaned with DI-WATER. As an example, in the surface cleaning of the quartz 11, the surface can be cleaned by deionized water sprayed from a nozzle. On the contrary, the quartz 11 can be immersed in a cleaning chamber filled with deionized water and cleaned.

In the chemical treatment step S30, the surface of the quartz 11 can be embossed by supplying a chemical solution to the surface of the quartz 11.

Wherein, by forming embossing on the surface of the quartz 11, the surface of the quartz 11 has a predetermined range of surface roughness (Ra).

In the present invention, the surface roughness of the quartz 11 may be in the range of 1 to 5 μm. Preferably, the surface roughness value of the quartz 11 may be in the range of 2 to 4 μm.

When embossing is formed on the surface of the quartz 11, the adhesion between the coating material and the surface of the quartz 11 can be easily ensured in the subsequent coating process.

The liquid medicine includes hydrofluoric acid, acidic ammonium bifluoride, organic acid and deionized water. Among them, organic acids include formic acid and citric acid.

The composition ratio of the organic acid in the chemical liquid may be 40% to 70%. The composition ratio of acidic ammonium bifluoride in the chemical solution may be 5% to 40%.

Preferably, in the composition ratio of the chemical solution, hydrofluoric acid may be 4%, acidic ammonium bifluoride may be 31%, formic acid may be 44%, citric acid may be 4%, and deionized water may be 17%.

In the chemical treatment step S30, when a chemical solution is supplied to the surface of the quartz 11, embossing can be formed by the following reaction formula.

SiO ₂ +4HFSiF ₄ +2H ₂ O Reaction formula (1)

SiO ₂ +4NH ₄ HF ₂ SiF ₄ +2NH ₄ F+2H ₂ O Reaction formula (2)

3NH ₄ HF ₂ +SiO ₂ (NH ₄ ) ₂ SiF ₆ +NH ₄ OH+H ₂ O Reaction formula (3)

NH ₄ HF ₂ +SiO ₂ (NH ₄ ) ₂ SiF ₆ +NH ₃ +2H ₂ O Reaction formula (4)

In the chemical treatment step S30, embossing can be formed on the surface of the quartz 11 through the above chemical reaction. Specifically, when the chemical solution is supplied, the mask material 13 is formed on the surface of the quartz 11 by the reaction formula (3) and the reaction formula (4). As shown in FIG. 4, a mask material 13 can be generated on a partial area of the surface of the quartz 11. That is, the acidic ammonium bifluoride reacts with the surface of the quartz 11 to produce the mask material 13.

Wherein, the generated mask material 13 may be ammonium hexafluorosilicate.

As shown in FIG. 4, there is a region 15 on the surface of the quartz 11 where the mask material 13 is not formed. The surface area 15 of the quartz 11 where the mask material 13 is not formed on the surface of the quartz 11 reacts with the organic acid and the remaining substances. As shown in FIG. 5, the surface of the quartz 11 can be etched.

That is, embossing is formed on the surface of the quartz 11, so that a predetermined range of surface roughness can be obtained.

The chemical treatment step S30 includes a first surface treatment step S31, an intermediate cleaning step S32, and a second surface treatment step S33.

In the first surface treatment step S31, the surface of the quartz 11 can be treated for the first time by supplying a chemical solution on the surface of the quartz 11. Perform the first surface treatment process similarly to the above process.

The intermediate cleaning step S32 may be performed after the first surface treatment step S31. In the intermediate cleaning step S32, the surface of the quartz 11 is cleaned. As an example, the surface of quartz 11 can be cleaned with deionized water. In the intermediate cleaning step S32 and the cleaning step S40 described later, the mask material 13 and the etched quartz 11 can be cleaned.

The second surface treatment step S33 may be performed after the intermediate cleaning step S32. The second surface treatment step S33 is a step of performing a second treatment on the surface of the quartz 11 by supplying a chemical solution to the quartz 11. The second surface treatment step S33 may be performed similarly to the first surface treatment process described above.

As shown in FIG. 7, in the chemical treatment step S30, the above-mentioned process is repeated, so that the embossed area formed on the surface area of the etched quartz 1 can have a gentle cross section.

The cleaning step S40 may be performed after the chemical treatment step S30. As an example, in the cleaning step S40, the surface of the quartz 11 may be cleaned with deionized water. As an example, in the cleaning step S40, the mask material 13 formed on the surface of the quartz 11 or the etched quartz 11 may be removed.

The drying step S50 may be performed after the washing step S40. In the drying step S50, the cleaning liquid adhering to the surface of the quartz 11 may be dried. As an example, the drying step S50 may be performed by supplying an inert gas on the surface of the quartz 11. As an example, the inert gas can be supplied in the form of argon or nitrogen.

FIG. 8 is a diagram showing a comparison of the surface state of quartz when the surface of the quartz is not processed, when the surface treatment is performed by the sandblasting process, and when the chemical treatment process is used.

Referring to Fig. 8, the effect of the present invention will be explained.

When ceramic coating is performed without performing the surface treatment of the quartz 11, the coating film may peel off. In contrast, when the surface of the quartz 11 is sandblasted and then coated, chips or cracks can be confirmed on the surface.

In contrast, when the surface of the quartz 11 was chemically treated with a chemical solution, no chips or cracks were found on the surface of the quartz 11.

Chips or cracks generated on the surface of the quartz 11 can cause problems in the semiconductor manufacturing process due to the ceramic or quartz 11 on the surface being attached to the substrate during the process. Unlike this, when performing the quartz 11 surface treatment method of the present invention At this time, even if the quartz 11 is coated, chips or cracks will not be formed on the surface, so the possibility of foreign matter generated in the semiconductor manufacturing process is low.

As described above, in an embodiment of the present invention, the surface of the quartz is formed with a predetermined range of surface roughness by the chemical liquid, thereby preventing the formation of chips or cracks on the surface even after spraying. In addition, it can prevent foreign matter from being generated in the semiconductor manufacturing process.

The foregoing detailed description exemplifies the invention. In addition, the foregoing is intended to describe preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications can be made within the scope of the concept of the invention disclosed in this specification, the scope equivalent to the foregoing disclosure, and/or the scope of technology or knowledge in the art. The foregoing examples illustrate the most preferred embodiments, and various changes can be made to the specific practical fields and uses of the present invention. Therefore, the above detailed description of the invention is not intended to limit the invention to the disclosed embodiments. It should be understood that the scope of the appended invention claims is intended to include other embodiments.

S10‧‧‧Preparation steps

S20‧‧‧Prepare cleaning steps

S30‧‧‧Chemical treatment steps

S31‧‧‧First surface treatment step

S32‧‧‧Intermediate cleaning step

S33‧‧‧Second surface treatment step

S40‧‧‧Cleaning steps

S50‧‧‧Drying step

Claims (7)

A quartz surface treatment method for coating the surface of quartz. The method for surface treatment of quartz used in semiconductor manufacturing equipment before spraying with other substances includes: a preparation step of preparing the above-mentioned quartz; a chemical treatment step , The chemical treatment is performed by supplying a chemical solution to the surface of the quartz to form embossing on the surface of the quartz. The chemical treatment step includes; the first surface treatment step is to supply the chemical solution to the quartz to treat the quartz The surface of the quartz is treated for the first time; the intermediate cleaning step is to clean the surface of the quartz after the first surface treatment step; and the second surface treatment step is to supply the chemical solution to the quartz after the intermediate cleaning step To perform a second treatment on the surface of the quartz; a cleaning step, to clean the surface of the quartz after the chemical treatment step; and a drying step, to dry the surface of the quartz. In the semiconductor manufacturing process, plasma The semiconductor manufacturing equipment used in the etching process or semiconductor diffusion process supplies the quartz, the chemical solution contains organic acid and acidic ammonium bifluoride, the composition ratio of the organic acid is 40% to 70%, and the composition ratio of the acidic ammonium bifluoride is 5 % To 40%, in the above chemical treatment step, the acidic ammonium bifluoride reacts with the surface of the quartz to generate a mask material on a partial area of the surface of the quartz, and the surface area of the quartz without the mask material It reacts with the above-mentioned organic acid to etch the surface of the above-mentioned quartz. According to the first item of the scope of patent application, the quartz surface treatment method for coating the surface of quartz, wherein the chemical solution is composed of hydrofluoric acid, the acidic ammonium bifluoride, the organic acid and deionized water, and the organic acid includes formic acid and Citric acid. According to the second item of the scope of patent application, the quartz surface treatment method for coating quartz surface, wherein, in the composition ratio of the above-mentioned chemical solution, the above-mentioned hydrofluoric acid is 4%, the above-mentioned acidic ammonium bifluoride is 31%, and the above-mentioned formic acid is 44%, the above citric acid is 4%, and the above deionized water is 17%. According to the first item of the scope of patent application, the quartz surface treatment method for coating the surface of quartz further includes a preparatory cleaning step of cleaning the surface of the quartz before the chemical treatment step. The quartz surface treatment method for coating a quartz surface according to the first item of the patent application, wherein the cleaning step and the intermediate cleaning step are steps of removing the mask material generated on the surface of the quartz. According to the fifth item of the scope of patent application, the quartz surface treatment method for coating quartz surface, wherein the above-mentioned mask material is ammonium hexafluorosilicate. The quartz surface treatment method for coating the surface of quartz according to any one of items 1 to 6 of the scope of patent application, wherein, after the above chemical treatment step, the surface roughness of the above quartz is 1 to 5 μm.

Images