TW201913803A - Quartz surface treatment method for quartz surface coating preventing forming of chipping or crack after coating and performing chemical treatment before spraying other substances - Google Patents

Abstract

The present invention relates to a quartz surface treatment method for quartz surface coating, which is a surface treatment method for the quartz surface applied in semiconductor processing equipment before spraying other substances. According to an embodiment of the present invention, the present invention comprises: a preparation step of preparing the quartz; a chemical processing step of performing chemical treatment by supplying a chemical solution to the quartz surface to form an embossed pattern on the quartz surface; a cleaning step of cleaning the quartz surface after the chemical processing step; and a drying step of drying the quartz surface. In the art of semiconductor manufacturing process, the quartz is supplied to the semiconductor processing equipment used for plasma etching or semiconductor diffusion technique. The chemical solution contains an organic acid and an acidic ammonium bifluoride (NH4HF2). In the above chemical treatment step, the acidic ammonium bifluoride reacts with the quartz surface to generate mask matter in partial area of the quartz surface, and the area of the quartz surface not generating the mask matter is reacted with the organic acid, so as to etch the quartz surface.

Description

 Quartz surface treatment method for coating quartz surface  

The present invention relates to a method of treating a surface of a quartz used in a manufacturing apparatus for a semiconductor, and more particularly to a method of chemically treating a surface of quartz prior to spraying a surface of quartz.

Quartz products have high purity (99.999%), chemical stability, acid resistance, heat resistance (softening point temperature of 1683 ° C), excellent light transmission, small thermal expansion, excellent electrical insulation, and thus can be widely applied to semiconductors. , optical communications, electrical, electronics and other industries.

For example, in a conventional germanium wafer processing process, a germanium wafer is processed by processes such as chemical vapor deposition (CVD), etching, ashing, etc., in which quartz products are used. Support or configure the wafer.

Since a high temperature of 1000 ° C or more is applied in the above process, the portion where the wafer is in contact with the quartz surface causes a stress due to a difference in thermal expansion coefficient between the quartz and the germanium wafer, and a contact mark can be generated at the contact portion of the wafer (mark ).

In the case where the substance generated during the processing of the tantalum wafer is attached to the surface of the quartz material product to form a film, when the quartz material product is cooled after the treatment, the coefficient of thermal expansion between the film and the glass is different. Cracking or breaking can occur in quartz material products.

Moreover, 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 strong. Thus, the above film is still present during the subsequent processing of the tantalum wafer, and even if the quartz material product does not cause cracking or cracking, particles are generated before the film falls from the surface.

In order to prevent the generation of contact marks and reduce the contact area on the wafer, a sand blast treatment is performed on the surface of the quartz material product to roughen the surface of the quartz material product, and an uneven sandblasted surface can be formed.

Further, when the blast-treated surface is formed, the stress generated in the cooling step after the ruthenium wafer is treated on the surface of the blasted quartz is dispersed in various directions, thereby preventing the substance adhering to the quartz surface from being cooled. Dropped from the above surface.

However, when the blasting surface is in contact with the wafer, the cerium oxide particles are scraped off from the wafer, or the cerium oxide particles are confined inside the blasting surface, and in the molding step of the quartz material product, sandblasting is performed. The cerium oxide particles expand inside the surface region, and during the wafer processing, the particles float from the surface and the particles are dropped onto the surface of the patterned wafer, so that the blasted quartz surface can cause pattern defects.

The size of the generated particles is in the range of 0.2 μm to 5 μm, and even if the particle size is 0.3 μm or a small size of less than 0.3 μm, it can become a serious problem, and in particular, in recent years, in a fine semiconductor process, it is required A wiring pattern of 0.18 μm or less is an important problem in preventing the formation of the above-described fine particles in such a fine semiconductor process, which may cause a decrease in yield in semiconductor wafer fabrication.

That is to say, due to the characteristics of the quartz material, the surface treatment of quartz by the existing blasting process is highly brittle, so cracks can occur due to stress generated during blasting, and sparks can be generated on the surface, making it difficult to manipulate fine intervals and shapes. Complex quartz material. Moreover, only one product can be processed in one operation, and therefore, workability and productivity are lowered, and it is difficult to apply to a large-sized object.

In order to solve the above problems, the present invention provides a quartz surface treatment method for treating the surface of quartz by a chemical treatment process instead of a sand blasting process.

The present invention is not limited thereto, and other objects not mentioned may be clearly understood by those skilled in the art from the following description.

The present invention provides a method of surface treating the surface of quartz used in a semiconductor manufacturing apparatus prior to 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 quartz; and a chemical treatment step of performing chemical treatment by supplying a chemical solution to the surface of the quartz so as to be The surface of the quartz is embossed; the cleaning step is to clean the surface of the quartz after the chemical treatment step; and the drying step is to dry the surface of the quartz, and in the semiconductor manufacturing process, to an etching process using a plasma or semiconductor diffusion The semiconductor manufacturing apparatus used in the process supplies the quartz, the chemical liquid comprising an organic acid and an acidic ammonium hydrogen fluoride, and in the chemical treatment step, the acidic ammonium hydrogen fluoride reacts with the surface of the quartz to be on a surface of the quartz A masking substance is formed in the region, and a surface region of the quartz in which the masking substance is not formed is reacted 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 above organic acid may be 40% to 70%, and the composition ratio of the above acidic ammonium hydrogen fluoride may be 5% to 40%.

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

According to an embodiment, in the composition ratio of the chemical liquid, the hydrofluoric acid may be 4%, the acidic ammonium hydrogen fluoride may be 31%, the formic acid may be 44%, the citric acid may be 4%, and the deionization may be performed. The water can be 17%.

According to an embodiment, the chemical processing step may include: a first surface treatment step of performing the first treatment on the surface of the quartz by supplying the chemical liquid to the quartz; an intermediate cleaning step, in the first surface treatment After the step, the surface of the quartz is cleaned; and a second surface treatment step is performed, after the intermediate cleaning step, the surface of the quartz is subjected to a second treatment by supplying the chemical liquid to the quartz.

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

According to an embodiment, the cleaning step and the intermediate cleaning step may be a step of removing the mask substance generated on the surface of the quartz.

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

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

The effects of the present invention are not limited to the above effects, and those not mentioned in the present specification and the drawings can be clearly understood by those skilled in the art.

11‧‧‧Quartz

13‧‧‧ Masking substance

15‧‧‧Area

S10‧‧‧Preparation steps

S20‧‧‧Preparation of cleaning steps

S30‧‧‧Chemical treatment steps

S31‧‧‧First surface treatment steps

S32‧‧‧Intermediate cleaning steps

S33‧‧‧Second surface treatment steps

S40‧‧‧ cleaning steps

S50‧‧‧ drying step

Fig. 1 is a view sequentially showing a process of spraying a surface on which quartz is produced.

2 is a view sequentially showing a method of spraying a surface of a quartz by a process including chemically treating a quartz surface according to an embodiment of the present invention.

3 is a flow chart sequentially showing a quartz surface treatment method for coating a quartz surface according to an embodiment of the present invention.

4 to 7 are views schematically showing a process of forming an embossing on the surface of quartz.

Fig. 8 is a view showing a comparison of the surface state of quartz when a chemical treatment process is used when the surface of quartz is not treated, when surface treatment is performed by a sand blasting process.

Embodiments of the present invention will be described in further detail below with reference to the accompanying 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 embodiments. This embodiment is provided to more fully describe the present invention to those skilled in the art. Therefore, the shapes of the elements in the drawings may be exaggerated to emphasize a clearer description. Moreover, the terms or words used in the specification and the scope of the claims should not be construed as limited to the ordinary or dictionary meaning, and the inventor can appropriately define the concept of the term to describe the invention in the best way, and should be It is interpreted as conforming to the meaning and concept of the technical idea of the present invention.

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

Quartz supplied to the above semiconductor manufacturing equipment is usually supplied by spraying.

Fig. 1 is a view sequentially showing a process of spraying a surface on which quartz is produced.

Referring to this, the surface treatment was previously performed by a sandblasting process before the surface of the quartz was sprayed. The blasting process is a process of forming embossing on the surface of quartz by a mechanical process. However, when a sand blasting process is used, Chipping or Crack can be generated on the surface of the quartz.

When debris or cracks are formed on the surface of the quartz, even if the surface of the quartz is sprayed, foreign matter can be generated in the plasma etching process or the diffusion process, thereby causing a problem.

2 is a view sequentially showing a method of spraying a surface of a quartz by a process including chemically treating a quartz surface according to an embodiment of the present invention.

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

Fig. 3 is a flow chart sequentially showing a method of treating a quartz surface for coating a quartz surface according to an embodiment of the present invention, and Figs. 4 to 7 are views schematically showing a process of forming an 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 washing step S40, and a drying step S50.

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

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

In the chemical treatment step S30, embossing can be formed on the surface of the quartz 11 by supplying the chemical liquid to the surface of the quartz 11.

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

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 the embossing is formed on the surface of the quartz 11, the adhesion between the coating and the surface of the quartz 11 can be easily ensured in the coating step to be performed later.

The chemical solution includes hydrofluoric acid, acidic ammonium hydrogen fluoride, 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 solution may be 40% to 70%. The composition ratio of the acidic ammonium hydrogen fluoride in the chemical liquid may be 5% to 40%.

Preferably, in the composition ratio of the chemical liquid, hydrofluoric acid may be 4%, acidic ammonium hydrogen fluoride 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 the chemical liquid is supplied to the surface of the quartz 11, the 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 by the above chemical reaction. Specifically, when the chemical solution is supplied, the masking substance 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 substance 13 can be formed in a partial region of the surface of the quartz 11. That is, the acidic ammonium hydrogen fluoride reacts with the surface of the quartz 11 to form the masking substance 13.

The mask substance 13 formed may be ammonium hexafluoroantimonate.

As shown in FIG. 4, a region 15 where the masking substance 13 is not formed exists on the surface of the quartz 11. The surface region 15 of the quartz 11 on which no mask substance 13 is formed on the surface of the quartz 11 reacts with the organic acid and the remaining substance, and 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 surface roughness of a predetermined range 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 subjected to the first treatment by supplying the chemical liquid on the surface of the quartz 11. The first surface treatment process is performed similarly to the above process.

The intermediate washing 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 the 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 the second treatment on the surface of the quartz 11 by supplying the chemical solution to the quartz 11. The second surface treatment step S33 can be performed similarly to the first surface treatment process described above.

As shown in Fig. 7, in the chemical treatment step S30, the above process is repeated, so that the embossed region formed in the surface region of the etched quartz 1 has a gentle cross section.

The washing 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 can be washed with deionized water. As an example, in the cleaning step S40, the mask substance 13 formed on the surface of the quartz 11 or the etched quartz 11 can be removed.

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

Fig. 8 is a view showing a comparison of the surface state of quartz when a chemical treatment process is used when the surface of quartz is not treated, when surface treatment is performed by a sand blasting process.

The effect of the present invention will be described with reference to Fig. 8 .

When the ceramic coating is performed without performing the surface treatment of the quartz 11, the coating film can be peeled off. On the other hand, when the surface of the quartz 11 is subjected to sandblasting and coating, cracks or cracks can be confirmed on the surface.

On the other hand, when the surface of the quartz 11 was chemically treated with the chemical liquid, no debris or crack was observed on the surface of the quartz 11.

The cracks or cracks generated on the surface of the quartz 11 may be caused by problems in the semiconductor manufacturing process because the surface ceramic or quartz 11 may be attached to the substrate during the process, and unlike this, when the quartz 11 surface treatment method of the present invention is performed At the time, even if the quartz 11 is coated, no debris or cracks are formed on the surface, so that there is a low possibility that foreign matter is generated in the semiconductor manufacturing process.

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

The foregoing detailed description illustrates the invention. Furthermore, the foregoing is intended to be illustrative of the preferred embodiments of the invention, and may be used in various other combinations, modifications and environments. That is, it is possible to make changes or modifications within the scope of the concept of the invention disclosed in the present specification, the scope of the invention, and the scope of the technology or knowledge of the art. The foregoing embodiments illustrate the most preferred embodiments, and various modifications may be made in the specific field of the invention and the application. Therefore, the detailed description of the invention is not intended to limit the invention to the disclosed embodiments. It is to be understood that the scope of the appended claims is intended to cover the invention.

Claims (9)

 A quartz surface treatment method for coating a quartz surface, which is directed to a method for surface treatment of a surface of quartz used in a semiconductor manufacturing apparatus before spraying with other substances, comprising: a preparation step of preparing the quartz; and a chemical treatment step a chemical treatment by supplying a chemical solution to the surface of the quartz to form an embossing on the surface of the quartz; a cleaning step of cleaning the surface of the quartz after the chemical treatment step; and a drying step of performing the surface of the quartz Drying, in the semiconductor manufacturing process, supplying the quartz to a semiconductor manufacturing apparatus used in an etching process using a plasma or a semiconductor diffusion process, the chemical liquid comprising an organic acid and an acidic ammonium hydrogen fluoride, in the above chemical treatment step, the acidity Ammonium hydrogen fluoride reacts with the surface of the quartz to form a mask substance in a partial region of the surface of the quartz, and a surface region of the quartz in which the mask substance is not formed reacts with the organic acid to etch the surface of the quartz.    A method for treating a quartz surface for coating a quartz surface according to the first aspect of the invention, wherein the composition ratio of the organic acid is 40% to 70%, and the composition ratio of the acidic ammonium hydrogen fluoride is 5 % to 40%.    The method for treating a surface of quartz for coating a quartz surface according to the second aspect of the patent application, wherein the chemical liquid is composed of hydrofluoric acid, the above-mentioned acidic ammonium hydrogen fluoride, the organic acid and deionized water, and the organic acid includes formic acid and Citric acid.    A method for treating a quartz surface for coating a quartz surface according to the third aspect of the patent application, wherein, in the composition ratio of the chemical liquid, the hydrofluoric acid is 4%, and the acidic ammonium hydrogen fluoride is 31%, and the formic acid is 44%, the above citric acid was 4%, and the above deionized water was 17%.    A method for treating a quartz surface for coating a quartz surface according to the second aspect of the invention, wherein the chemical treatment step comprises: a first surface treatment step of supplying the surface of the quartz by supplying the chemical solution to the quartz. a first treatment; an intermediate cleaning step of cleaning the surface of the quartz after the first surface treatment step; and a second surface treatment step of supplying the chemical solution to the quartz after the intermediate cleaning step The surface of the quartz is treated a second time.    A method of treating a quartz surface for coating a quartz surface according to the fifth aspect of the invention, wherein the step of cleaning the surface of the quartz is further included before the chemical treatment step.    A method for treating a quartz surface for coating a quartz surface according to the fifth aspect of the invention, wherein the cleaning step and the intermediate cleaning step are steps of removing the mask substance formed on the surface of the quartz.    A method for treating a quartz surface for coating a quartz surface according to the seventh aspect of the invention, wherein the masking substance is ammonium hexafluoroantimonate.    The method for treating a surface of quartz for coating a quartz surface according to any one of claims 1 to 8, wherein the surface roughness of the quartz after the chemical treatment step is 1 to 5 μm.