TWI405743B - Multi-component thermal spray coating material for semiconductor processing equipment, and manufacturing and coating method thereof - Google Patents

Abstract

PURPOSE: A multi-component ceramic coating material for being thermally sprayed is provided to reduce internal defects of a protection coating film, to improve corrosion resistance, and to prolong the life span of the parts. CONSTITUTION: A multi-component ceramic coating material for being thermally sprayed on the parts of semiconductor processing devices comprises a composition of Al_(2(1-x))Zr_xO_(3-x), wherein x is 0.2-0.8. A method for preparing the coating material for the thermal spray comprises the steps of: mixing Al2O3 particles and ZrO2 particles with a diameter 0.1-30 microns to prepare a material with a composition of Al_(2(1-x))Zr_xO_(3-x); spraying and drying the material to form synthetic powder; and incinerating the powder at 800-1500 °C.

Description

Multi-component thermal spray material for semiconductor processing equipment and method of manufacturing and coating same Cross-references for related applications

This application claims the priority and benefit of Korean Patent Application No. 10-2009-0049115 (applied on June 3, 2009 at the Korea Intellectual Property Office, the entire contents of which are incorporated herein by reference) .

Background of the invention (a) Field of invention

This invention relates to a multicomponent thermal spray material for use in parts of semiconductor processing equipment, and methods of making and coating the same.

(b) Related technical description

A vacuum plasma system is widely used in the field of semiconductor device manufacturing methods and other ultrafine pattern forming methods. In a vacuum plasma system apparatus, there is a plasma-promoted chemical vapor deposition (PECVD) apparatus, in which a deposition layer is formed on a substrate by chemical vapor deposition mainly by plasma for physical use. A method of forming a deposition layer of a sputtering apparatus, and a dry etching apparatus for etching a substrate or a coating thereon to have a desired pattern.

Vacuum plasma systems etch semiconductor components or form ultra-fine patterns by using a high temperature plasma. When the high temperature plasma is generated in the vacuum plasma system, the chamber of the system and its built-in parts are damaged. Furthermore, it is highly likely that special elements and contaminating particles will be generated from the surface of the chamber and its parts and thus contaminate the interior of the chamber.

In particular, for a plasma etcher, when the reaction gas having the contents of F or Cl is injected into the chamber under a plasma atmosphere, the inner walls of the chamber and its built-in parts are placed in a severe corrosive environment. This corrosion primarily damages the chamber and its built-in parts, and secondly produces contaminating materials and particles, so that the products processed in the chamber have an increased defect ratio and deteriorated quality.

The above information disclosed in the Background section is only for the purpose of promoting an understanding of the background of the invention, and therefore, it may contain information that is not formed in the art for those skilled in the art.

Summary of invention

The present invention is directed to providing a coating material for a chamber of a vacuum plasma system and its built-in parts, which has reduced internal defects of a protective coating film during ceramic thermal spraying to promote corrosion resistance and increase The advantage of product life, and in particular, provides a coating material having a markedly improved etching resistance in a plasma etching atmosphere mainly composed of Cl groups, and exhibiting a coating material for manufacturing and coating the coating material. The method.

An exemplary embodiment of the present invention provides a thermal spray material for a semiconductor processing apparatus. The thermal spray material has a composition of Al _2(1-x) Zr _x O _3-x , wherein x is preferably in the range of from about 0.2 to about 0.8, and more preferably in the range of from 0.2 to 0.5. In the case where the value of x is 0.5 or less, the material has almost a non-crystalline structure, and in the case where the value of x exceeds 0.5, the material has a composite structure in which the ZrO ₂ structural phase is mixed with the matrix amorphous structure. .

The thermal spray material may comprise a powder having a particle diameter of from 1 μm to 100 μm.

For a thermal spray material for use in a semiconductor processing apparatus, a material having a composition of Al _{2 (1-x)} Zr _x O _3-x , wherein x is preferably in the range of from about 0.2 to about 0.8. More preferably, it is in the range of 0.2 to 0.5, which is first provided by mixing Al ₂ O ₃ particles and ZrO ₂ particles each having a diameter of 0.1 μm to 30 μm. This material is then spray dried to form a synthetic powder. Thereafter, the powder is sintered at 800 ° C to 1500 ° C.

For the step of mixing this material, static electricity can be applied to the Al ₂ O ₃ particles and the ZrO ₂ particles so that the individual particles have electrostatic charges of different polarities.

For the step of applying static electricity, polymethylmethacrylium ammonium salt (Darvan C) is added to the solvent such that the Al ₂ O ₃ particles have a negative electrostatic charge, and polyvinyl quinone imine (PI) is added to the solvent to make ZrO ₂ particles have a positive static charge.

For a method of coating a thermal spray material for a semiconductor processing apparatus, a thermal spray material having a composition of Al _{2 (1-x)} Zr _x O _3-x wherein x is preferably from 0.2 to 0.8 The range, and more preferably in the range of 0.2 to 0.5, is prepared first. The thermal spray material is then injected into a plasma flame to heat the material. A thermally sprayed material that is completely melted or semi-melted by heating is deposited on a surface of a part for a semiconductor processing apparatus to form a coating film having a non-crystalline structure.

For the step of providing a coating film, an intermediate metal layer can be formed.

For the step of providing a coating film, a coating film having an oblique gradient can be formed by sequentially distinguishing the compositions of the thermal spraying materials.

Furthermore, the coating film having an oblique gradient can be sequentially changed to Al _2(1-x) Zr _x O _3- by making the composition of the thermal spray material identical or similar to the composition of the base to be coated. The composition of _x , wherein x is preferably formed in the range of 0.2 to 0.8, and more preferably in the range of 0.2 to 0.5.

For the step of providing a coating film, the part can be a chamber of a vacuum plasma system or a built-in part of the chamber. The value of x may range from 0.2 to 0.5, and the thermal spray material may comprise a powder having a particle diameter of from 1 μm to 100 μm.

For a coating material for a chamber of a plasma processing system and its built-in parts according to an exemplary embodiment of the present invention, internal defects of the protective coating film during thermal spraying of the ceramic are reduced, and thus, Promotes corrosion resistance and increases part life.

In particular, for the coating material, the etching resistance in the plasma etching atmosphere mainly composed of Cl groups is remarkably promoted.

Simple illustration

Figure 1 is a vertical cross-sectional view of a plasma etcher as a semiconductor processing apparatus.

Figure 2 is a schematic cross-sectional view of a plasma gun for a plasma thermal spray system.

Fig. 3 is a scanning electron microscope (SEM) photograph of a cross section of a yttria (Y ₂ O ₃ ) coated film formed by using an external injection type plasma gun.

Fig. 4 is a SEM photograph of a cross section of a yttrium oxide (Y ₂ O ₃ ) coated film formed by using an internal injection type plasma gun.

Fig. 5 shows the results of X-ray analysis of a yttria (Y ₂ O ₃ ) coated film conventionally used for coating in a large amount.

Figure 6 is a schematic diagram showing the process of volume change when the liquid phase material is cooled to a solid phase material.

Fig. 7 is a schematic view showing a process of forming a crack when the liquid phase is transferred to a crystal phase.

Figure 8 is a schematic illustration of the volumetric shrinkage process as the liquid material cools to an amorphous phase.

Fig. 9 is a schematic view showing a method of avoiding the formation of crack-like defects when the liquid phase is transferred to an amorphous phase.

Fig. 10 is a view showing a method of producing a thermally sprayed composite powder having a large particle size by mixing a heterogeneous powder.

Figure 11 is a SEM photograph of a cross section of a coating film of Al _2(1-x) Zr _x O _3-x (x system 0.4) coated with a thermally sprayed composite powder according to an exemplary embodiment of the present invention.

Figure 12 is an X-ray analysis result of a coating film of Al _2(1-x) Zr _x O _3-x (x system 0.4) coated with a thermally sprayed composite powder according to an exemplary embodiment of the present invention. .

FIG. 13 illustrates an Al ₂ O ₃ and Y ₂ O ₃ thermal spray film according to the prior art, an Al-YO-based amorphous coating film according to a patent publication application, and one according to the present invention. The results of the comparative examples of the Al _2(1-x) Zr _x O _3-x (x-based 0.4) coating films are relatively rigid with each other.

Figure 14 is a SEM photograph of a cracked Al _{2 (1-x)} Zr _x O _3-x (x-based 0.4) coated film in accordance with an exemplary embodiment of the present invention.

Fig. 15 is a view showing an Al ₂ O ₃ , Y ₂ O ₃ , and B ₄ C coating film which is currently used as a protective film for a semiconductor processing apparatus, and Al _2(1-x) Zr according to an exemplary embodiment of the present invention. _x O _3-x (x-based 0.4) A comparison result of the etching resistance of the amorphous coating film in an etching environment mainly composed of F groups.

Fig. 16 is a photograph of a reaction product on the surface of an Al ₂ O ₃ coated film according to the prior art by plasma etching using an etching gas mainly composed of F groups.

Fig. 17 is a photograph of a reaction product on the surface of a Y ₂ O ₃ coated film according to the prior art by plasma etching using an etching gas mainly based on F groups.

Figure 18 is a plasma etching of an Al _{2 (1-x)} Zr _x O _3-x (x system 0.4) according to an exemplary embodiment of the present invention by using an etching gas mainly composed of an F group. High resolution photo on the surface of the crystalline coating film.

Fig. 19 illustrates the results of comparison of the corrosion resistance (for plasma) of the Al ₂ O ₃ and Y ₂ O ₃ thermal spray coatings and the coating film according to an exemplary embodiment of the present invention.

Detailed description of the embodiment

The invention will be more fully described hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.

Here, i) the shape, size, ratio, angle, number, movement, and the like shown in the drawings are merely exemplified and can be improved;

Ii) the drawing is drawn according to the viewpoint of the viewer, and the direction or position of the drawing can be changed according to the position of the viewer;

Iii) throughout the specification, the same reference numbers indicate the same elements;

Iv) words "including", "having", "including" are understood to include the element, but do not exclude any other element unless the word "only" is included;

v) When the description is in the singular, it can also be interpreted as a plural;

Vi) even if numerical values, shapes, dimensional comparisons, positional relationships, etc. are not described as "about" or "substantially", they are interpreted as encompassing a general range of error;

Vii) even if the words "after", "before", "after", "and", "here", "after", etc. are used, they are not used to specifically define the current position;

Viii) the words "first", "second" and the like are used selectively, interchangeably or repeatedly to facilitate a simple distinction in a convenient manner and are not intended to be limiting;

Ix) It is to be understood that when an element is referred to as "on", "upper", "lower" or "side" of another element, it may be directly above, above, below, or side, or Or a plurality of intervening elements may also be present; and

x) When two elements A and B are placed together with "A or B", they can be interpreted as containing elements A and B, but when these elements are placed together with "not A or B", they will It is interpreted as including only one of these components.

Figure 1 is a schematic diagram of a plasma dry etcher. Corrosion of a vacuum plasma chamber and its parts of this plasma etcher will be described with particular reference to Figure 1.

The plasma dry etching apparatus is, for example, used to etch a substrate (e.g., a semiconductor wafer) or a target portion of a film formed thereon to form a desired circuit or pattern on the substrate.

As shown in FIG. 1 , the plasma dry etching device comprises a chamber wall 1 , upper/lower electrodes 2 and 9 , an insulating window 3 , a support frame 4 , inner/outer supports 5 and 6 , and a connection transporter 7 . A substrate support 8, a plasma screen 10, a lining 11, a lining heating device 12, a gas diffusion plate 13, a fixed chuck 16, and a focus ring 17. The detailed description of the above elements is omitted for convenience, as they can be easily understood by those skilled in the art.

The structural components of this device and its operating principles can be described as follows. The etching gas flows into a chamber through a hole 14 formed in a gas diffusion plate 13. When an etching gas flows in, an RF current is applied to an upper electrode 2 and a lower electrode 9 to generate plasma and promote reactivity into the etching gas. The reactive etching gas is urged to collide with a substrate 15 on a support 8 to partially etch the substrate 15 or a film coated thereon.

The etching gas contains a gas containing F, such as C ₄ F ₈ , C ₅ H ₈ , CH ₂ F ₂ , CF, CF ₂ , CF ₃ , CF ₄ , SF ₆ , NF ₃ , F ₂ , CH ₂ F ₂ , CHF ₃ , and C ₂ F ₆ , a gas containing Cl, such as Cl ₂ , BCl ₃ , SiC ₁₄ , and HCl, a gas containing Br, such as HBr, Br ₂ , and CF ₃ Br, and SiN ₄ , O ₂ , a mixture of Ar, H ₂ , or the like.

However, the etching gas also affects the structural components other than the substrate 15 to which the target is etched. That is, the chamber of the etching apparatus and its built-in parts are chemically or physically damaged during the manufacturing process by the extreme atmosphere within the chamber.

When the etching method is a method in which a physicochemical impact is caused by using a corrosive gas, an accelerating ion, and a plasma applied to a part or the entire surface of the substrate to cause damage thereto, and the damaged portion is removed, The interior surface of the chamber and its built-in parts are also damaged by the same method. More specifically, the chamber and its built-in parts are subject to chemical attack due to highly chemically reactive etching gases. At the same time, the ionized gas particles are accelerated by the RF electromagnetic field, thus causing ion collisions on the surface of the chamber parts. In this way, the chamber is also subject to physical attacks.

As described above, in the event that the chamber and its built-in parts are damaged by the etching method, the damaged parts of the etching apparatus need to be replaced, cleaned, or repaired, and this brings additional cost. Furthermore, the processing line needs to be stopped in order to replace, clean, or repair the device, and this results in increased processing time.

In addition, because the contaminated material from the damaged chamber and the surface of its built-in parts can contaminate the wafer or LCD glass substrate to be etched, the defect ratio of the semiconductor and LCD increases.

Accordingly, various techniques have been introduced to increase the durability of vacuum plasma processing chambers and their built-in parts, and their conventional representatives for avoiding corrosion of vacuum plasma chambers and their built-in parts will be described below.

Vacuum plasma chambers are generally formed from stainless steel alloys, metallic materials such as aluminum or aluminum alloys and titanium or titanium alloys, or ceramic materials such as SiO ₂ , Si, and Al ₂ O ₃ .

The technique of forming an Al ₂ O ₃ ceramic coating film on the surface of the base by anodizing has been widely used for parts related to Al alloys. However, since the ceramic coating film mainly composed of this technique has many defects inside, it is difficult to obtain high rigidity and corrosion resistance, and the contaminated particle system is highly likely to be generated.

Meanwhile, for various metals and ceramics in which it is difficult to apply an anodizing method, a protective layer is formed by using a material which exhibits higher corrosion resistance from the outside and lower contamination particles.

A coating technique for thermally spraying a coating material in an individual or mixed manner is known, but this technique is problematic because when the material is coated in this manner, the characteristics of the coating film are severely deteriorated due to internal defect formation.

Further, a method of forming a protective layer by using a heterogeneous ceramic is also used for the Al-alloy material which can use the anodizing method. The most representative way to form a protective layer by using a heterogeneous ceramic is thermal spraying.

Thermal spraying is a coating technique in which a metal or ceramic powder is injected into a high temperature plasma flame and heated to completely melt or semi-melt. In this state, the coating material is applied to the surface of the base to form a coating film.

Figure 2 illustrates a plasma gun 20 that is the primary component of a thermal spray apparatus.

As shown in Fig. 2, the plasma gun 20 includes a cathode 22, a cooling passage 23, an anode 24, a support 26, and a powder injection device 27. The detailed description of the above elements is omitted for convenience, as they can be easily understood by those skilled in the art. The operating principle of the plasma gun 20 is as follows.

First, a plasma gas (such as Ar, N ₂ , H ₂ , and He) flowing through a gas injection hole 21 passes through a gap between a cathode 22 and an anode 24, during which a high power is applied (usually 30). To 100V, or 400 to 1000A), and at this time, the injected gas is partially decomposed to form a high temperature plasma flame 25 in the range of 5,000 to 15,000 °C.

The cathode 22 is generally formed of tungsten or a tungsten-reinforced metal material to prevent corrosion of the end portion of the cathode which is a portion of the plasma. The anode 24 is formed of copper or a copper alloy and has a built-in cooling passage 23 to prevent the anode life from being lowered by high temperature plasma.

The homogeneous or heterogeneous material can be applied to the surface of various materials such as metal and ceramic by thermal spraying, and a powder or a linear metal or ceramic can be used as the coating material.

Thereafter, the coating material is powdered and injected into a high temperature plasma flame 25 via a powder injection device 27. The powder injection device 27 can be fixed to the plasma gun by a support 26 (hereinafter referred to as an external type) or to the anode 24 (hereinafter referred to as an internal type).

The powder injected through the powder injection device 27 is completely melted or partially melted by a high-temperature plasma flame, and the fluid 28 at a high speed of 200 to 1000 m/s is caused to fly toward the coating target 30 to form a coating film 29.

If the ceramic oxide is sprayed by thermal spraying of the plasma, the coating can be carried out under an air atmosphere, but if the metal, carbide, or nitride which is easily oxidized or easily decomposed at a high temperature is coated, the coating is applied. It is sprayed by plasma heat spraying in a vacuum low temperature chamber.

However, thermal spray films are not sufficient to solve the problems that occur during actual semiconductor fabrication methods.

3 and 4 are SEM photographs of a cross section of a protective coating film formed by thermally spraying Y ₂ O ₃ , which is widely used as a protective coating material for parts of a semiconductor processing apparatus.

From the photograph of Fig. 3, it is known that the protective film coated by using an external plasma gun has a large number of irregular defects.

The coated film formed under the above conditions has relatively good mechanical properties such as rigidity, but this film has disadvantages because it depends on the distance between the plasma gun and the base, and the injected gas (such as He, H _{2 ).} The amount of , and Ar), and the thermal spray conditions of the applied power are extremely sensitive. Furthermore, since a large amount of electric power needs to be applied during the coating method, the energy efficiency is deteriorated. Further, a gas such as hydrogen which is advantageous in raising the plasma temperature is required to be used to melt a material having a high melting point such as ceramic, and in this case, a black dot is liable to be formed by the Y ₂ O ₃ coating film.

Figure 4 is a photograph of a section of a film coated by using a plasma gun of the above internal type. From the photograph of Fig. 4, it is known that the particles hit the surface of the base to form a splash, and most of the cracks form a slit perpendicularly in the splash, while the gap is formed at the edge region between the splashes.

The coating film formed under these conditions has poor mechanical properties such as rigidity, and the inside of the sputtering is broken and the edge gap at the sputtering is operated as a passage for the diffusion reaction gas. Therefore, the corrosion reaction of the coating film is promoted, and therefore, the formation of contaminating particles is accelerated. Furthermore, the coated film can be easily damaged by the semiconductor manufacturing method or the mechanical impact applied during the cleaning.

Now, the reason for the internal cracking of the splash and the edge gap of the splash generated when the conventional ceramic material is coated by thermal spraying will be explained with reference to Figs. 5 to 7 .

Fig. 5 illustrates an X-ray analysis structure when Y ₂ O _{3 which} is conventionally used as a protective coating material for a part of a semiconductor processing apparatus in a large amount is thermally sprayed. It is understood from Fig. 5 that the conventional coating material is formed in a crystalline phase. Fragmentation which occurs due to the formation of the crystalline phase coating film will now be more specifically explained.

For liquid phase ceramics, constituent elements (for example, Y and O in Y ₂ O ₃ ) are loosely bonded to each other, and the order of arrangement of these elements occurs irregularly. When the liquid phase ceramic is cooled to a temperature lower than its melting point Tm, it is transferred to a solid state, and thus, the crystal phase and the constituent elements in which the bonding of the constituent elements become stronger are regularly formed. Figure 6 illustrates the volume change as the liquid phase material is cooled and transferred to a crystalline phase solid.

When the temperature is lowered, the ceramic material shrinks due to a decrease in the distance between atoms constituting the elements. When the crystal phase in which the constituent elements are regularly arranged is formed, rapid volume shrinkage (ΔV in Fig. 6) occurs. This rapid volume shrinkage causes internal cracking at the splash and edge gaps at the splash during thermal spraying. Figure 7 illustrates a method of forming such defects.

When the liquid phase material is transferred to a solid phase having the same atomic configuration as the liquid phase, it is referred to as an amorphous phase. Figure 8 is a graph showing the change in volume when the liquid phase material is cooled to an amorphous phase. It can be seen that unlike the case where cooling occurs to form a crystalline phase, no basis volume shrinkage exists. As described above, if the amorphous phase is formed when the thermal spray material is cooled on the surface of the base, the possible excessive shrinkage of the volume accompanying the cooling does not exist, and therefore, as illustrated in Fig. 9, a crack and a splash gap therebetween A cooling film in which the formation of the holes is avoided can be obtained.

In order to cool and convert the liquid thermally sprayed ceramic into a crystalline phase solid, all constituent elements need to be disposed in situ. Therefore, the more the types of constituent elements are, the more complicated the arrangement structure of the crystal phase atoms becomes. Moreover, when multiple elements need to be moved to individual predetermined locations, it takes a considerable amount of time to achieve the desired configuration. Furthermore, if the thermodynamically stable material is mixed with a heterogeneous element, it advantageously forms an amorphous phase.

Whether or not the amorphous phase is formed with respect to various combinations of elements is identified by the present invention. As a result, the amorphous phase is easily formed as a mixture of Al-Zr-O atoms, and the crack of the coating film and the edge pores at the sputtering are lowered.

In the case where a coated film is formed by using a multi-component ceramic according to an exemplary embodiment of the present invention, when the amount of Zr is increased, the fraction of the amorphous phase is lowered, and the fraction of the crystalline phase of ZrO ₂ is increased. In the case where the composition of the Al _2(1-x) Zr _x O _3-x composition exceeds 0.5, the crystal phase starts to form, and the fraction of the crystal phase increases in proportion to the amount of increase in Zr. However, even when x is increased up to 0.8, the occurrence of internal chipping is considerably suppressed due to the formation of the amorphous matrix.

A method of forming a coating film mainly composed of Al-Zr-O according to an exemplary embodiment of the present invention will be described in detail.

A coating material according to an exemplary embodiment of the present invention comprises a multicomponent element having a three-component element of Al-Zr-O to easily form a coating film of an amorphous phase. The evaluation relates to a coating film containing Y, Si, N, and C in addition to the triple Al-Zr-O composition, but there is no special characteristic improvement regarding strength, rigidity, and etching resistance. . However, it is apparent that the formation of the amorphous phase occurs more easily by adding Y, Si, N, and C in addition to the element Al-Zr-O. Therefore, the present invention is not deteriorated by adding a few elements to the element Al-Zr-O.

The ratio of the constituent elements of the multicomponent ceramic material is established such that the composition of the composition having Al _2(1-x) Zr _x O _3-x is preferably in the range of 0.2 to 0.8, and more preferably 0.2. To the range of 0.5. In the case where the x system is less than 0.2, the ratio of the crystal phase of Al ₂ O ₃ increases. Conversely, in the case where the value of x exceeds 0.8, the fraction of the crystal phase of ZrO ₂ increases, making it difficult to remove internal defects by forming an amorphous phase. In the case where the x series is in the range of 0.2 to 0.5, a coated film having a substantially 100% amorphous phase can be obtained.

Multicomponent ceramic materials in accordance with one exemplary embodiment of the present invention can be formed in a variety of ways, and the most common manner of formation will now be described.

Al ₂ O ₃ particles and ZrO ₂ particles each having a size of 0.1 μm to 30 μm are prepared to form a composition of Al _2(1-x) Zr _x O _3-x (x system 0.2 to 0.8), It is mixed with a solvent, a binder, and a dispersing agent. Then, the mixture is spray-sprayed at a temperature of 70 to 80 ° C or by a fine groove structure of a high-speed rotating disk to form a powder having a diameter of 1 μm to 200 μm.

At the same time, the powder is uniformly mixed, and the multi-component mixture powder can be made into Al _{2 (1)} by making the Al ₂ O ₃ and ZrO ₂ particles having a size of 0.1 μm to 30 μm have charges of different polarities and mixing the charged particles. _-x) A composition of Zr _x O _3-x (x is in the range of from about 0.2 to about 0.8). In the case where the Al ₂ O ₃ powder and the ZrO ₂ powder are simply mixed mechanically, the mixture of the Al ₂ O ₃ powder and the ZrO ₂ powder may be uneven. However, when the two particles are loaded with different charges in a solvent having a specific acidity (for example, pH 6), the heterogeneous powder can be uniformly mixed. To make these powders chargeable, polymethylmethacrylium ammonium salt (Darvan C) can be added to the solvent to make Al ₂ O ₃ negatively charge, while polyvinyl quinone imine (PI) is added to the solvent to make ZrO ₂ carrying a negative charge.

For this method of preparing one of the above-described spray-dried powders, the subsequent processing steps are the same as those for the spray dryer, and the detailed description thereof is omitted.

Since the powder prepared by this method has weak strength, it is further heated at 900 to 1500 °C. For this heating step, the solvent, binder, and dispersant are evaporated leaving only the ceramic powder. When the remaining ceramic powder is sintered, the strength of the powder is promoted. The heat treatment step can be omitted occasionally and the subsequent steps are carried out.

Meanwhile, for the method of synthesizing the ceramic powder according to an exemplary embodiment of the present invention, in the case of mixing the Al ₂ O ₃ powder and the ZrO ₂ powder, a solvent and a dispersing agent may be used to make the mixing easier and to make the mixed particles uniform. dispersion. Further, a binder can be used to maintain shape during post processing, such as calcination.

A mixture of water, acetone, isopropyl alcohol, or the like can be used as the solvent used in the ceramic synthesis method, and the high molecular polymer is used as a dispersant. A polymer such as PVB 76 or benzyl decanoate can be used as a binder.

Fig. 10 is a diagram showing a method of producing a coating powder mainly composed of Al-Zr-O-.

A method of forming a coating film by using ceramic powder according to an exemplary embodiment of the present invention will now be described in detail.

The coating method according to an exemplary embodiment of the present invention comprises thermal spraying. For thermal spraying, the ceramic powder is injected into the plasma flame to heat it and form a fully molten or semi-molten powder, and the powder is deposited on the surface of the part of the plasma chamber (hereinafter referred to as the "base") to form a Coating the film.

First, a coating powder was prepared. The ceramic powder for thermal spraying is a powder having a particle size of from 1 μm to 100 μm according to an exemplary embodiment of the present invention. A powder having a particle size of from 20 μm to 60 μm is preferably used.

The monomer powder and coalesced powder are then injected into the plasma flame. The injected powder is heated by a flame while being scattered and deposited on the surface of the base. The deposited powder is cooled at a rate to form a coating film.

Various operating conditions can be established to effect this coating in a stable manner and to promote the properties of the coating material. The operating conditions may vary depending on the size of the equipment and the coating powder to be used.

Example

The invention will now be more particularly illustrated by the examples. For an embodiment of the present invention, a SG-100 plasma gun manufactured by Praxair, USA, is used, and power is applied to the plasma gun by using a power application system "PT-800" manufactured by Plasmatech, Switzerland. Re-soil, argon and helium were used to form a plasma and were individually controlled at 401/min and 201/min. At the same time, the applied power was established to be 25 to 36 Kw (600 A, 60 V), and the injection speed of the coated powder was 10 g/min. The distance between the plasma gun and the coated target is established to be approximately 120 mm.

The excellent properties of the coating material according to the present invention will now be described on the basis of a powder having a composition of Al-YO- based on Al _{2 (1-x)} Zr _x O _3-x (x system 0.4). Fig. 11 is a SEM photograph of a cross section of a coating film mainly composed of Al _{2 (1-x)} Zr _x O _3-x (x system 0.4). Although partially broken in the vertical direction, it was confirmed that the amount of cracks and voids was significantly lowered as compared with the Y ₂ O ₃ film according to the comparative example of Fig. 4. Fig. 12 is a view showing an X-ray diffraction result of a coating film mainly composed of a composition of Al _2(1-x) Zr _x O _3-x (x system 0.4) in Fig. 11. In view of the absence of specific crystal phase peak formation, it is known that most of this film is formed as an amorphous phase.

Fig. 13 is a view showing an Al ₂ O ₃ coating as a comparative example, a Y ₂ O ₃ coating which has been conventionally used in a large amount, and an Al-in the case of Korean Patent Application No. 10-2007-0060758. The YO-based amorphous coating is rigid to each other with the coating of Al _2(1-x) Zr _x O _3-x (x system 0.4) according to an embodiment of the present invention. It is understood that the coating according to this embodiment is about 10% higher than the Al ₂ O ₃ coating and about 25% higher than the Al-YO-based amorphous coating. Figure 14 is a SEM photograph of a fragmented Al _{2 (1-x)} Zr _x O _3-x (x system 0.4) coated film. As shown in this photograph, the coated film has a structure which is extremely rigid like a sintered ceramic material, and the film can be expected to have high mechanical strength.

Figure 16 illustrates the durability of a part of a plasma vacuum chamber having a coated film in accordance with an exemplary embodiment of the present invention. The durability was evaluated by etching the coating material with CF ₄ + O ₂ gas using a plasma etcher which is one of the semiconductor processing apparatuses, and measuring the etching depth.

Durability measurement conditions are more specifically described below. First, the etching resistance in a plasma etching environment containing an etching gas mainly composed of F- was investigated.

The injection speed of CF ₄ gas was established to be 40 sccm (standard cubic meter / minute), the injection speed of O ₂ gas was 10 sccm, the main electrode input power was 1000 W, the bias power was 150 W, and the pressure of the etching chamber was 5 mtorr. The internal temperature of the chamber was maintained at 25 °C.

As shown in Fig. 16, the etching resistance is improved by about 4 to 5 times more than the Al ₂ O ₃ or B ₄ C according to the comparative example, and is substantially similar to the etching gas mainly known as F-based. Y ₂ O ₃ exhibiting excellent tolerance.

When the bias power is established under the previous plasma etching conditions, the reaction product is attached to the surface of the base. Fig. 16 is a SEM photograph of the surface of an Al ₂ O ₃ coated film according to a comparative example in which particles produced by a reaction of 100 to 200 nm were observed. Particles generated during semiconductor processing contaminate the semiconductor and cause an increased defect ratio. Therefore, such particles need to be prevented from falling on the surface of the semiconductor, and more preferably, particles produced by the reaction of tens to hundreds of nanometers or more are prevented from being produced.

Figure 17 is a SEM photograph of the surface of the plasma-etched Y ₂ O ₃ coated film with a higher resistance to the F-based etching solution than the Al ₂ O ₃ coating film. Compared with Al ₂ O ₃ film by coating, the fine particles generated in the reaction was observed on the surface of the coating film of Y ₂ O _3.

Meanwhile, Fig. 18 illustrates a plasma-etched Al _2(1-x) Zr _x O _3-x (x system 0.4) coating film according to the present embodiment. Unlike the Al ₂ O ₃ and Y ₂ O ₃ coating films according to the comparative examples, the reaction-free product was found on the Al _{2 (1-x)} Zr _x O _3-x coating film, and the effect of extremely positive can be expected. The reduction in semiconductor defect ratio is reduced during application to semiconductor processing.

Finally, the etch resistance is investigated in a plasma etch environment containing a Cl-based etching gas in accordance with an exemplary embodiment of the present invention. For semiconductor processing, various corrosive gases (such as Cl ₂ , BCl ₃ , SiCl ₄ , CHF ₃ , SF ₆ , HBr, NF ₃ , CF ₄ C ₂ F ₆ , TOES, TIMB, TIMP, N ₂ O, and C) ₂ F ₆ ) is used. In the meantime, there are several processing steps using a corrosive gas containing a Cl group. The Cl-based etching gas system is extremely corrosive, and there is no existing material which is excellent in resistance to it. Therefore, processing defects are improved, and the promotion of semiconductor ability is hindered. Therefore, it has become extremely important to develop an etching resistant coating material which is durable to a Cl-based etching gas in the related art. In order to study the resistance of a Cl-based etching gas to an Al-Zr-O-based coating material according to an exemplary embodiment of the present invention, 100 sccm of BCl ₂ gas and 100 sccm of Cl ₂ gas are applied to The target is simultaneously generated by using a transformer coupled plasma (TCP) source. The etching test was carried out under the condition that the main power was established at 800 W, the bias power was 200 W, and the chamber pressure of the etching apparatus was 20 mtorr. As shown in Fig. 19, the etch resistance is promoted to 1600% in relation to the Al ₂ O ₃ coating, and is related to the Y ₂ O ₃ coating as a comparative example and the Korean Patent Application No. 10-2007-0060758 The Al-YO-based amorphous coating proposed by the No. XI case promoted 200%. It can be seen that the non-crystalline coating or the amorphous/crystalline composite coating mainly composed of Al-Zr-O- has higher mechanical properties and etching resistance than all coating materials according to the comparative example, or is equal thereto. . In particular, under the Cl-based plasma etching atmosphere, which is the most recent problem in semiconductor processing, Al-Zr-O- is the mainstay of the traditional materials to promote 200% to 1600%. Etch resistance, and this means that it can be extremely useful for semiconductor processing.

It should be noted that the compositional formula of the composition formula Al _2(1-x )Zr _x O _3-x , Al:Zr:O of the coating material according to an exemplary embodiment of the present invention is not absolutely in accordance with 2(1-x): x:3-x. This is because the ceramic powder originally used partially deviates from the chemically stable composition formula Al ₂ O ₃ or ZrO ₂ , or the mixture powder is decomposed by heating at a high temperature when passing through the ultra-high temperature plasma, so that oxygen and others evaporate to cause a composition ratio. Minor changes.

While the invention has been described with respect to the embodiments of the present invention, it is understood that the invention is not intended to Improved and equalized configuration.

1. . . Chamber wall

2. . . Upper electrode

3. . . Insulated window

4. . . Support frame

5. . . Inner support

6. . . Outer support

7. . . Connection transporter

8. . . Substrate support

9. . . Lower electrode

10. . . Plasma screen

11. . . lining

12. . . Lining heating device

13. . . Gas diffusion plate

14. . . hole

15. . . Substrate

16. . . Fixed chuck

17. . . Focus ring

20. . . Plasma gun

twenty one. . . Gas injection hole

twenty two. . . cathode

Figure 1 is a vertical cross-sectional view of a plasma etcher as a semiconductor processing apparatus.

Figure 2 is a schematic cross-sectional view of a plasma gun for a plasma thermal spray system.

Fig. 3 is a scanning electron microscope (SEM) photograph of a cross section of a yttria (Y ₂ O ₃ ) coated film formed by using an external injection type plasma gun.

Fig. 4 is a SEM photograph of a cross section of a yttrium oxide (Y ₂ O ₃ ) coated film formed by using an internal injection type plasma gun.

Fig. 5 shows the results of X-ray analysis of a yttria (Y ₂ O ₃ ) coated film conventionally used for coating in a large amount.

Figure 6 is a schematic diagram showing the process of volume change when the liquid phase material is cooled to a solid phase material.

Fig. 7 is a schematic view showing a process of forming a crack when the liquid phase is transferred to a crystal phase.

Figure 8 is a schematic illustration of the volumetric shrinkage process as the liquid material cools to an amorphous phase.

Fig. 9 is a schematic view showing a method of avoiding the formation of crack-like defects when the liquid phase is transferred to an amorphous phase.

Fig. 10 is a view showing a method of producing a thermally sprayed composite powder having a large particle size by mixing a heterogeneous powder.

Figure 11 is a SEM photograph of a cross section of a coating film of Al _2(1-x) Zr _x O _3-x (x system 0.4) coated with a thermally sprayed composite powder according to an exemplary embodiment of the present invention.

Figure 12 is an X-ray analysis result of a coating film of Al _2(1-x) Zr _x O _3-x (x system 0.4) coated with a thermally sprayed composite powder according to an exemplary embodiment of the present invention. .

FIG. 13 illustrates an Al ₂ O ₃ and Y ₂ O ₃ thermal spray film according to the prior art, an Al-YO-based amorphous coating film according to a patent publication application, and one according to the present invention. The results of the comparative examples of the Al _2(1-x) Zr _x O _3-x (x-based 0.4) coating films are relatively rigid with each other.

Figure 14 is a SEM photograph of a cracked Al _{2 (1-x)} Zr _x O _3-x (x-based 0.4) coated film in accordance with an exemplary embodiment of the present invention.

Fig. 15 is a view showing an Al ₂ O ₃ , Y ₂ O ₃ , and B ₄ C coating film which is currently used as a protective film for a semiconductor processing apparatus, and Al _2(1-x) Zr according to an exemplary embodiment of the present invention. _x O _3-x (x-based 0.4) A comparison result of the etching resistance of the amorphous coating film in an etching environment mainly composed of F groups.

Fig. 16 is a photograph of a reaction product on the surface of an Al ₂ O ₃ coated film according to the prior art by plasma etching using an etching gas mainly composed of F groups.

Fig. 17 is a photograph of a reaction product on the surface of a Y ₂ O ₃ coated film according to the prior art by plasma etching using an etching gas mainly based on F groups.

Figure 18 is a plasma etching of an Al _{2 (1-x)} Zr _x O _3-x (x system 0.4) according to an exemplary embodiment of the present invention by using an etching gas mainly composed of an F group. High resolution photo on the surface of the crystalline coating film.

Fig. 19 illustrates the results of comparison of the corrosion resistance (for plasma) of the Al ₂ O ₃ and Y ₂ O ₃ thermal spray coatings and the coating film according to an exemplary embodiment of the present invention.

Claims (13)

A thermal spray material for a semiconductor processing apparatus having a non-crystalline structure of one of Al _{2 (1-x)} Zr _x O _3-x , wherein x is 0.2 to 0.8. The thermal spray material of claim 1, wherein the x value is 0.2 to 0.5. The thermal spray material of claim 1, wherein the thermal spray material comprises a powder having a particle diameter of one of 1 μm to 100 μm. A method of fabricating a thermal spray material for a semiconductor processing apparatus, the method comprising: providing an Al by mixing each of Al ₂ O ₃ particles having a diameter of 0.1 μm to 30 μm with ZrO ₂ particles A material of a composition of _2(1-x) Zr _x O _3-x wherein x is 0.2 to 0.8; the material is spray dried to form a synthetic powder; and the powder is calcined at 800 ° C to 1500 ° C. The method of claim 4, wherein the step of mixing the material comprises applying static electricity to the Al ₂ O ₃ particles and the ZrO ₂ particles such that the individual particles have electrostatic charges of different polarities. The method of claim 5, wherein the step of applying the static electricity comprises: adding a polymethylmethacrylium ammonium salt (Darvan C) to the solvent to cause the Al ₂ O ₃ particles to have a negative static charge; And adding polyvinylimine (PI) to the solvent to give the ZrO ₂ particles a positive static charge. A method of coating a thermal spray material for a semiconductor processing apparatus, the method comprising: preparing a thermal spray material having a composition of Al _{2 (1-x)} Zr _x O _3-x , wherein the x system 0.2 to 0.8; injecting the thermal spray material into a plasma flame to heat the material; and depositing the thermal spray material completely or semi-molten via the heating on a surface of one of the parts for the semiconductor processing apparatus A coating film having a non-crystalline structure is provided. The method of claim 7, wherein the step of providing the coating film comprises forming an intermediate metal layer. The method of claim 7, wherein the step of providing the coating film comprises forming a coating film having an oblique gradient by sequentially distinguishing the composition of the thermal spray material. The method of claim 9, wherein the composition of the thermal spray material is sequentially changed from Al _{2 (1-x) to a} composition identical or similar to the composition of the base to be coated. The composition of Zr _x O _3-x wherein x is from 0.2 to 0.8. The method of claim 7, wherein the part is a chamber of a vacuum plasma system or an internal part of the chamber for the step of forming the coating film. The method of claim 7, wherein the value of x is from 0.2 to 0.5. The method of claim 7, wherein the thermal spray material comprises a powder having a particle diameter of from 1 μm to 100 μm.