JP4021325B2 - Manufacturing method of parts for plasma processing apparatus - Google Patents

Description

The present invention relates to a plasma processing apparatus for unit goods manufacturing how.

  Conventionally, in a semiconductor manufacturing process, for example, by using a plasma etching apparatus, an object to be processed such as a semiconductor wafer is subjected to an etching process, and a desired fine processing is performed on the surface of the object to be processed. .

  In this type of plasma processing apparatus, an upper electrode and a lower electrode are arranged opposite to each other in an airtight apparatus main body, and high frequency power is applied to the lower electrode on which an object to be processed is placed to lower the upper electrode and the upper electrode. Glow discharge is generated between the two. By this glow discharge, the processing gas supplied into the processing chamber is turned into plasma, and the workpiece is etched. Conventionally, CF (fluorocarbon) -based gas has been widely used as the processing gas.

In this plasma etching apparatus, the main body of the apparatus is made of anodized Al (aluminum) metal as a base material, and a sintered Al ₂ O ₃ (alumina) ceramic member is detachably attached to the inside of the main body of the apparatus. It is installed over the entire circumference.

In the conventional plasma etching apparatus, the apparatus main body is composed of an Al outer wall part and an inner wall part made of an Al ₂ O ₃ (alumina) ceramic member that is detachably attached to the inner peripheral surface of the outer wall part. Even when the inner wall of the apparatus main body is scraped and damaged by the plasma, the processing of the object to be processed can be resumed by replacing only the inner wall portion.

  Further, in a conventional plasma etching apparatus, components such as a focus ring, a baffle plate, and a shield ring are used to effectively confine plasma between an upper electrode and a lower electrode and perform a desired etching process on an object to be processed. (Hereinafter referred to as “in-chamber components”), that is, device components are arranged at predetermined positions around the upper electrode and the lower electrode.

This in-chamber component is required to have an insulating performance with a dielectric constant of 10 or less, and has been conventionally formed of quartz (SiO ₂ ), or a polyimide (PI) -based or polyamide-imide (PAI) -based resin material.

However, the SiO ₂ material, which is often used as a component material for the components in the chamber, has a large amount of crushing dust generated on the component surface during machining. When the plasma etching apparatus is operated with the crushed debris attached, the crushed debris becomes solid fine particles and scatters in the plasma atmosphere and adheres to the surface of the workpiece.

  For this reason, until the number of solid fine particles adhering to the object to be treated is within an allowable range (for example, the number of solid fine particles having a particle size of 0.2 μm or more is within 30), It is used for dummy operation. After the dummy operation, a new processed object is dry-etched to obtain a semiconductor product that has been subjected to desired fine processing.

  However, as described above, although conventional chamber components made of quartz or PI or PAI resin materials are exposed to the plasma atmosphere, these quartz or PI or PAI resin materials are Since it is inferior in plasma resistance, it can be easily scraped off by the plasma process gas, so these parts in the chamber must be frequently replaced with new ones as consumable parts, which requires labor and maintenance for the equipment. There was a problem that it was inferior in nature.

Further, in the conventional plasma etching apparatus, since the inner wall portion of the apparatus main body is formed of an Al ₂ O ₃ ceramic member as described above, Al ₂ O ₃ reacts with a CF-based gas as a processing gas. Thus, AlF ₃ (aluminum fluoride) is generated. The pressure in the processing chamber (chamber) approaches the vapor pressure of AlF ₃ (1.6 × 10 ⁻⁴ Pa at room temperature of 20 ° C.) due to the low pressure and high power of the processing chamber accompanying the microfabrication of the workpiece. ₃ becomes solid fine particles. The solid fine particles of AlF ₃ fall off from the inner wall portion and the parts arranged in the apparatus main body and are scattered in the plasma atmosphere. The scattered AlF ₃ solid fine particles adhere to the surface of the object to be processed, causing Al contamination which is a kind of metal contamination, resulting in a decrease in product yield.

Furthermore, when SiO ₂ material is used as a chamber internal part, a large amount of crushed debris adheres to the surface of the SiO ₂ material, so it takes a long time until the number of solid fine particles scattered in the plasma atmosphere is within the allowable range. There was a problem that a dummy operation had to be performed.

Therefore, the present invention has been made in view of such problems, and improves the plasma resistance of parts exposed to the plasma atmosphere disposed in the apparatus main body to extend the maintenance cycle. and its object is to provide a manufacturing how a plasma processing apparatus for unit products can be achieved.

Further, the present invention can improve the product yield by avoiding metal contamination of the object, producing a plasma processing apparatus for unit products capable of improving the productivity with further improved durability of components an object of the present invention is to provide an mETHODS.

  The inventors of the present invention conducted extensive research to find a material for a plasma processing apparatus component having excellent plasma resistance. Polybenzimidazole (hereinafter referred to as “PBI”) is made of quartz, PI resin, PAI resin, or the like. Compared to the parts materials used in conventional chamber parts, it has superior plasma resistance and adhesion, so it easily adsorbs solid particles generated in the processing chamber and scatters the solid particles. The knowledge that it can avoid as much as possible depositing on things was acquired.

  On the other hand, since PBI has a property of high water absorption, when PBI is used in a state of absorbing water as it is, there is a possibility that moisture adheres to the object to be processed and adversely affects the product.

As a measure to remove the moisture adhering to the workpiece, it is possible to remove the moisture by performing the dummy operation for a certain period of time after stopping the supply of processing gas after etching the workpiece. requires extra time for, it leads to reduced productivity.

Therefore , in the method for manufacturing a component for a plasma processing apparatus according to the present invention, after the PBI powder is vacuum-dried, the vacuum-dried powder is molded to produce a molded product having a predetermined shape , A first annealing treatment performed at a temperature of 280 ° C. to 300 ° C. for 2 to 4 hours and a second annealing treatment performed at a temperature of 340 ° C. to 360 ° C. for 2 to 4 hours are performed at the time of machining after the forming treatment. the it is with the features.

Also, from the viewpoint of avoiding the occurrence of cracking of the parts for a plasma processing apparatus the first drying treatment temperature vacuum drying process again a molded article with a high second drying treatment temperature than that is set in a vacuum drying process Is preferred.

In the method of manufacturing components for a plasma processing apparatus, a vacuum drying process have preferably be carried out 5-7 hours at a temperature 140 ° C. to 180 ° C..

Also, in the manufacturing method of the component for a plasma processing apparatus, after the first annealing process twice, it is preferable to perform the second annealing process once.

In the method of manufacturing components for a plasma processing apparatus, after the cleaning process after machining has preferably be subjected to a vacuum drying process performed 2 to 4 hours at a temperature 200 ° C. to 250 DEG ° C..

According to the above manufacturing method, since the PBI powder is molded after being vacuum dried, a desired PBI part can be easily obtained.

  DETAILED DESCRIPTION Hereinafter, a plasma processing apparatus component, a manufacturing method thereof, and a plasma processing apparatus according to embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an internal structural view showing an embodiment of a plasma etching apparatus as a plasma processing apparatus according to the present invention.

  In the processing chamber 22 in the plasma etching apparatus main body 1 (hereinafter referred to as the apparatus main body 1), a large number of various in-chamber parts formed in a predetermined shape are arranged at predetermined positions.

  Specifically, the apparatus main body 1 is provided with a lower electrode 2 made of a conductive material. An electrostatic chuck 4 for attracting and holding the semiconductor wafer 3 (object to be processed) is mounted on the upper surface of the lower electrode 2, and an elevating shaft 5 that can be moved up and down in the direction of arrow A is disposed below the lower electrode 2. The lower electrode 2 is supported by the lift shaft 5. The lifting shaft 5 is connected to a high frequency power source 7 through a matching unit 6.

  The electrostatic chuck 4 has a ceramic sprayed coating formed on an aluminum substrate by plasma spraying. It is preferable to apply methyl methacrylate as an impregnating agent on the surface of the sprayed coating for the purpose of sealing pores of the sprayed coating. By using methyl methacrylate as the impregnating agent, it is possible to sufficiently close the pores on the surface of the sprayed coating and form a desired heat transfer gas layer between the semiconductor wafer 3 and the electrostatic chuck 4, thereby The temperature of the semiconductor wafer 3 can be stably controlled.

  The bottom and side surfaces of the lower electrode 2 are covered and protected by the electrode protection member 8, and the side and bottom surfaces of the electrode protection member 8 are covered by the conductive member 9, and the conductive member 9 and the apparatus main body 1 are further protected. An expandable / contractible bellows 10 made of a conductive material such as stainless steel is attached between the inner bottom surface. A tubular member 11 made of an electrically conductive material such as oxidized aluminum is provided on the lower surface of the electrode protection member 8, and the lifting shaft 5 is inserted through the tubular member 11.

  A baffle plate 12 extending in the horizontal direction is fixed to the side surface of the electrode protection member 8, and a focus ring 13 and an insulator ring 40 are provided between the upper end surface of the electrode protection member 8 and the side surface of the electrostatic chuck 4. Is arranged. A first bellows cover 14 that extends downward is fixed to the lower surface of the baffle plate 12, and a second bellows cover is formed so as to partially overlap the first bellows cover 14 on the inner bottom surface of the apparatus body 1. 15 is erected.

  An upper electrode 16 made of a conductive material is disposed near the ceiling in the processing chamber 22 so as to face the lower electrode 2. A number of gas discharge holes 17 are formed in the upper electrode 16, and a processing gas containing a CF-based gas is supplied to the processing chamber 22 through the gas discharge holes 17 from a gas supply port 18 provided on the upper surface of the apparatus body 1. Is done. The gas supply port 18 is connected to a gas supply source 21 through a flow rate adjusting valve 19 and an on-off valve 20 provided in the gas pipe G. Accordingly, the processing gas supplied from the gas supply source 21 reaches the gas supply port 18 through the on-off valve 20 and the flow rate adjustment valve 19, is discharged from the gas discharge hole 17, and is introduced into the processing chamber 22.

  The upper electrode 16 is held at the periphery by a shield ring 41 formed of an insulating member. Further, a protective ring 42 is provided around the shield ring 41, and a shield member 43 is provided on the outer periphery of the protective ring 42. It is installed vertically.

  A discharge port 23 is formed at the bottom of the apparatus body 1. The discharge port 23 is connected to a vacuum pump 24, and a workpiece transfer port 25 is formed on the lower side surface of the apparatus body 1, and the semiconductor wafer 3 is loaded and unloaded through the workpiece transfer port 25. Is called.

  The semiconductor wafer 3 transferred into the processing chamber 22 through the workpiece transfer port 25 is masked and is electrostatically held by the electrostatic chuck 4.

  A permanent magnet 26 is disposed along the outer periphery of the side surface of the apparatus main body 1.

  By this permanent magnet, a magnetic field in a direction parallel to the surface to be processed of the semiconductor wafer 3 held by the electrostatic chuck 4 is generated in the processing chamber 22.

  In the plasma processing apparatus configured as described above, the position of the semiconductor wafer 3 is adjusted by moving the elevating shaft 5 in the direction of arrow A by a drive mechanism (not shown). The elevating shaft 5 functions as a power feeding rod, and can apply a high frequency power of 13.56 MHz, for example, from the high frequency power source 7 to the lower electrode 2. Glow discharge can be generated between the lower electrode 2 and the upper electrode 6 by applying the high frequency power. Thereby, an orthogonal electromagnetic field in which the electric field and the magnetic field are orthogonal is formed.

  The processing chamber 22 is decompressed to a predetermined vacuum atmosphere by the vacuum pump 24, and the processing gas from the gas supply source 21 is supplied to the processing chamber 22. This processing gas is turned into plasma, and a desired fine processing is performed on the surface to be processed of the masked semiconductor wafer 3 by the plasma confined between the lower electrode 2 and the upper electrode 16.

  Hereinafter, a first embodiment of the present invention will be described.

  In the first embodiment of the present invention, the in-chamber components exposed to the plasma atmosphere, that is, the focus ring 13, the shield ring 41, the protective ring 42, the shield member 43, the first and second bellows covers 14, 15 are: It is made of PBI resin with excellent plasma resistance.

  As described above, the semiconductor wafer 3 is subjected to a dry etching process, and the surfaces of the parts in the chamber that are exposed to the plasma atmosphere are also etched and consumed, so that these worn parts are replaced with new parts according to the degree of consumption. Need to be replaced. However, quartz, PI resin, and PAI resin that have been conventionally used as component materials for in-chamber components are inferior in plasma resistance. Therefore, it is necessary to frequently replace the in-chamber components to improve productivity. It was a hindrance.

  The experimental results of the present inventors have revealed that the PBI resin is superior in plasma resistance compared to the quartz, PI resin, and PAI resin. Therefore, in the first embodiment, the chamber is exposed to the plasma atmosphere. The inner part is made of PBI resin.

  Since this PBI resin has excellent adhesion, solid fine particles generated by reaction with the CF-based gas in the processing chamber 22 and scattered in the plasma atmosphere are easily adsorbed by the PBI resin chamber components. The solid fine particles can be effectively prevented from depositing on the object to be processed.

  By the way, the molecular structural formula of PBI is represented by the following general formula (1), and PBI contains an imide group (—NH group).

On the other hand, the processing gas is generally composed of a mixed gas containing Ar gas, O ₂ gas or the like in a CF-based gas. Therefore, in the processing chamber 22, the imide group of PBI reacts with O ₂ to react with a hydroxyl group (—OH group). ) Is produced. As a result, the amount of water absorbed by the PBI resin increases, and the water absorbed by the PBI resin may adhere to the semiconductor wafer 3.

  As a measure for removing water adhering to the semiconductor wafer 3, a method may be considered in which after a predetermined etching process is performed on the semiconductor wafer 3, the supply of the processing gas is stopped and a dummy operation is performed for a certain period of time so as to remove the moisture. However, this requires extra time for the dummy operation, and the productivity cannot be improved.

  Therefore, in the first embodiment of the present invention, the PBI resin is previously dried, and the dried PBI resin is used as the component material for the components in the chamber.

  Hereinafter, the manufacturing method of the in-chamber part will be described with reference to FIG.

  FIG. 4 is a flowchart showing the manufacturing process of the in-chamber components.

  First, the PBI powder was vacuum-dried by a vibration vacuum dryer at a temperature of 140 ° C. to 180 ° C. for 5 hours to 7 hours under a reduced pressure of 1,995 Pa (15 Torr) (S101). Then, a molded product having a predetermined shape, for example, a shape substantially corresponding to the focus ring 13, the shield ring 41, or the like is manufactured by a well-known hot press method (S 102), and then machining such as cutting is performed. Next, degreasing cleaning and pure water cleaning are performed (S104). During the machining, annealing is performed twice at a temperature of 280 ° C. to 300 ° C. for 2 to 4 hours, and then annealing is performed once at a temperature of 340 ° C. to 360 ° C. for 2 to 4 hours. Is preferred.

  Hereinafter, the verification test results of the annealing treatment temperature will be described.

  Annealing temperature verification test was conducted for cerazole sample A which was subjected to annealing treatment at 290 ° C. for 3 hours three times, and annealing treatment which was heated at 290 ° C. for 3 hours twice and then at 350 ° C. for 3 hours. The sample B of cerazole subjected to the annealing treatment to be heated once is heated at 120 ° C. or 350 ° C. for 30 minutes, and the outgas components generated at that time are measured. The results are shown in Table 1. .

  As is clear from Table 1, when heated at 350 ° C. for 30 minutes, 44 μg of phthalic anhydride and 17 μg of isobutyl alcohol are generated from 1 g of sample A, whereas 1 g of sample B contains phthalic anhydride. Only 5 μg and 1 μg of isobutyl alcohol are generated.

  From this, sample B contains only a small amount of impurities such as phthalic anhydride and isobutyl alcohol, that is, by performing annealing once at 350 ° C. for 3 hours, impurities in cerazole are removed. It turns out that there is an effect to remove.

  Thereafter, in order to avoid the occurrence of part cracking, vacuum drying was performed again at a temperature of 200 ° C. to 250 ° C. for 2 hours to 4 hours under a reduced pressure of 5,320 Pa (40 Torr) (S105). As a result, an in-chamber part made of PBI resin having a desired shape and a moisture content of 370 ppm or less can be manufactured.

  The water content was measured by highly accurate temperature-programmed desorption gas analysis.

  FIG. 5 is a characteristic diagram showing the change over time in the BTM (bottom) dimension of the etching groove. (A) shows the case where the PBI resin whose moisture content is suppressed to 370 ppm is used. When the PBI resin having a moisture content of 2240 ppm is used, respectively.

  In addition, the variation in BTM (bottom) size of etching grooves and changes over time were compared between the case where a PBI resin whose water content was suppressed to 370 ppm was used and the case where a PBI resin whose water content was 2240 ppm was used. . Thus, it can be seen that if the moisture content of the PBI resin is suppressed, variations in the BTM (bottom) dimension of the etching groove and changes with time can be suppressed.

  Further, the cleaning process after machining is performed as follows.

  The machined product is degreased and washed with pure water, removed heavy metal adhering to the surface with hydrofluoric acid, washed with pure water and ultrasonic, and then polished with a natural polymer material. Processing (polishing) is performed to remove solid fine particles on the surface, and then high-pressure cleaning and ultrapure water cleaning are performed, thereby performing cleaning processing after machining.

  As described above, according to the first embodiment of the present invention, since the in-chamber components exposed to the plasma atmosphere are formed of the PBI resin that has been subjected to the drying treatment, they are formed of quartz, PI resin, or PAI resin. The plasma resistance is improved as compared with the parts. As a result, the durability of the parts in the chamber is improved, the frequency of parts replacement is reduced, and the productivity can be improved.

  In addition, since the PBI resin has been subjected to a drying process, moisture does not adhere to the semiconductor product, and therefore, it is not necessary to perform an extra dummy operation and the usability is not impaired.

  Moreover, since the PBI resin is excellent in adhesion, even if the solid fine particles of the reaction product generated by reacting with the processing gas are scattered in the plasma atmosphere, it is easily adsorbed by the PBI chamber internal parts, Therefore, it is possible to avoid the solid fine particles from being deposited on the semiconductor product.

  Hereinafter, a second embodiment of the present invention will be described.

  In the second embodiment of the present invention, the apparatus main body 1 includes an anodized Al outer wall 1a and an inner wall 1b that is detachably mounted over the entire inner peripheral surface of the outer wall 1a. Further, the inner wall 1b is formed of a sintered ceramic material that does not contain an aluminum component, that is, an aluminum-less sintered ceramic material, so that even if the inner wall 1b is scraped by plasma, a semiconductor that is an object to be processed The wafer 3 is not contaminated by Al, and the product yield is improved.

  In the plasma processing apparatus, the in-chamber components such as the focus ring 13, the insulator ring 40, the electrode protection member 8, the baffle plate 12, and the first and second bellows covers 14 and 15 that are exposed to the plasma atmosphere are placed at predetermined positions. In the second embodiment of the present invention, the in-chamber parts are also formed of an aluminumless sintered ceramic material.

As the aluminumless sintered ceramic material, for example, one kind of material mainly composed of Si ₃ N ₄ , Y ₂ O ₃ , or SiC or two or more kinds of composite materials are used.

In addition, the SiO ₂ material, which has been widely used as a material for parts in the chamber from the past, needs to be operated for a long time because of the large amount of crushed debris generated during machining. Since the plasma resistance is also inferior, the exchange frequency is high and the productivity is poor.

For this reason, in the present embodiment, a material type that is excellent in plasma resistance as compared with SiO ₂ , and generates less crushed debris during machining than SiO ₂ , and therefore, dummy operation can be performed in a short time, that is, Si ₃ N ₄ , Y ₂ O ₃ , one or more composite materials mainly composed of SiC, preferably at least one of yttrium (Yb) and yttrium (Y) as a sintering aid The added material is used.

According to the experimental results of the present inventors, even when the chamber inner part (plasma-resistant part) is formed of the above-described aluminum-less sintered ceramic material in the same manner as the inner wall portion 1b, the chamber inner part is made of SiO _2. It becomes clear that the semiconductor wafer 3 can be finely processed with an etching rate substantially the same as that formed with a material, and therefore a desired etching rate can be ensured.

  These aluminum-less ceramic materials with excellent plasma resistance are well-known sintering methods such as atmospheric pressure sintering, pressure sintering (Hot Press), and isotropic pressure sintering (Hot Isostatic Press). Needless to say, it can be easily formed into a predetermined shape using a method.

  As described above, in the second embodiment of the present invention, since the inner wall portion 1b is formed of an aluminum-less sintered ceramic material, it is possible to avoid a situation in which the semiconductor wafer 3 as the object to be processed is contaminated with Al. The product yield can be improved.

Further, the chamber internal parts arranged inside the apparatus main body 1 are also made of aluminumless sintered mainly composed of Si ₃ N ₄ , Y ₂ O ₃ , SiC, etc. having excellent plasma resistance, like the inner wall 1b. Since it is formed of a ceramic material, preferably an aluminum-less sintered ceramic material to which at least one of yttrium and yttrium is added as a sintering aid, compared to the case of using a conventional SiO ₂ material, The time required for the dummy operation can be shortened. Therefore, the productivity can be improved while ensuring the etching rate substantially the same as that when the parts in the chamber are formed of SiO ₂ , and further, the plasma resistance of the parts is increased. Improvement, that is, durability can be improved.

By using an aluminumless sintered ceramic material mainly composed of Si ₃ N ₄ , Y ₂ O ₃ , SiC, etc., Al contamination can be surely avoided as described above. Since there is a possibility that the Fe component is mixed as an impurity in the commercially available product of the sintered ceramic material, there is a possibility that Fe contamination occurs as metal contamination other than Al contamination. However, such Fe contamination can be easily eliminated by reducing the Fe content.

  In the above embodiment, the magnetic field assist type plasma etching apparatus in which the permanent magnet 26 is disposed on the outer periphery of the apparatus main body 1 has been described as an example. However, instead of providing the permanent magnet 26, for example, the upper electrode Needless to say, the present invention can also be applied to an ion-assisted plasma etching apparatus that generates plasma by applying high-frequency power to both the lower electrode 2 and the lower electrode 2.

  Hereinafter, a third embodiment of the present invention will be described with reference to FIG.

  FIG. 11 is a schematic view showing a method of manufacturing a plasma processing apparatus component material in the third embodiment.

  In the third embodiment of the present invention, the component material for the plasma processing apparatus is manufactured by an oxyhydrogen melting method.

Specifically, the natural lens powder 101 a predetermined different materials having excellent plasma resistance with H ₂ and O ₂ (hereinafter, SiO ₂ powder 101) was added to, SiO ₂ powder 101 in the mixing can 102 and the heterologous Mix with ingredients. Thereby, the mixture 103 is obtained. Next, the mixture 103 is melted under a predetermined high-temperature gas atmosphere 104 (for example, 2000 ° C.), the melted mixture 103 is laminated on the ingot case 105 rotating in the direction of arrow A, and then naturally cooled to form an ingot. The part material 106 is manufactured.

As described above, in the third embodiment, the mixture 103 obtained by adding a predetermined dissimilar material to the SiO ₂ powder 101 is melted in the high temperature gas atmosphere 104 by the oxyhydrogen melting method as the gas melting method. _The part material 106 in which different kinds of materials are uniformly mixed in ₂ is manufactured.

Examples of the predetermined different materials include materials having excellent plasma resistance, specifically, rare earth compounds such as Y ₂ O ₃ , silicon compounds other than SiO ₂ such as SiC and Si ₃ N ₄ , Al ₂ O _{3, and the like.} Or a reaction product of a rare earth compound such as Y _{2 Al 5} O ₁₂ (yttrium-aluminum-garnet; YAG) and an aluminum compound can be used.

In the third embodiment, the content of the dissimilar material with respect to SiO ₂ is set to 1 wt% to 5 wt%.

  Here, the content of the dissimilar material is set to 1 wt% to 5 wt%. When the content of the dissimilar material is less than 1 wt%, the content of the dissimilar material is too small, which contributes to improvement of plasma resistance. On the other hand, even if a different material is contained in excess of 5 wt%, the plasma resistance is saturated and the effect of adding the different material cannot be achieved.

As described above, in the third embodiment, a predetermined dissimilar material having excellent plasma resistance, such as a rare earth compound, is uniformly added (mixed) into the SiO ₂ powder 101 by the oxyhydrogen melting method, and the component material 106 is obtained. Since it is manufactured, the plasma resistance of the parts for the plasma processing apparatus (shield ring 41, focus ring 13, insulating ring, etc.) manufactured using the component material 106 is improved, and the apparatus parts are replaced compared to the conventional one. The frequency is reduced, and the productivity of semiconductor manufacturing can be improved.

Examples Next, examples of the present invention will be described in detail.

  A first example corresponding to the first embodiment of the present invention will be described below.

[First embodiment]
In the present embodiment, the present inventors used two types of PBI (PBI-A and PBI-B) as PBI materials, and three types of PI (PI-A, PI-B, PI-C) as PI materials. In this case, one type of PAI (referred to as PAI-A) was used as the PAI material, and a test piece having a length of 20 mm, a width of 20 mm, and a thickness of 2 mm was produced using each of these materials. And as shown in FIG. 2, the outer peripheral part 30 of each test piece is masked with a polyimide film (DuPont, registered trademark “Kapton”), and an irradiation surface of 10 mm in length and 10 mm in width is provided in the central part 31. Plasma was irradiated for 20 hours under the discharge conditions described above, and the amount of abrasion (consumption amount) in the X-axis direction and Y-axis direction was measured with a surface roughness meter to evaluate plasma resistance.

[Discharge conditions]
High frequency power: 1300W
Power supply frequency: 13.56 MHz
Processing chamber pressure: 133 Pa (1.0 Torr)
Process gas components: CF ₄ / Ar / O ₂
FIG. 3 is a bar graph showing the measurement results, in which the horizontal axis represents each specimen material, and the vertical axis represents the amount of abrasion (μm) after 20 hours.

  As is apparent from FIG. 3, the PBI material is less consumed than the PI material and PAI material, and is excellent in plasma resistance.

  A second example corresponding to the second embodiment of the present invention will be described below.

[Second Embodiment]
The inventors first used a Si ₃ N ₄ material mainly composed of Si ₃ N ₄ as a present example, and a SiO ₂ material mainly composed of SiO ₂ as a comparative example. An insulator ring 40 having an inner diameter of 230 mm, an outer diameter of 280 mm, and an overall height of 15 mm was manufactured.

  Next, the insulator ring 40 is disposed at a predetermined position in the processing chamber 22, and an 8-inch (203.2 mm) semiconductor wafer 3 is attracted and held on the electrostatic chuck 4 to generate glow discharge under predetermined discharge conditions. Then, plasma irradiation was performed, and the number of solid fine particles before and after plasma irradiation was measured.

  Specifically, since crushed debris is adhered to the surface of the insulator ring 40 by machining, 5 pieces of semiconductor wafers 3 are used for 1 minute each to remove the crushed debris, for a total of 5 Then, a new semiconductor wafer 3 was attracted and held on the electrostatic chuck 4 and plasma irradiation was performed for 30 seconds, and the number of solid particles before and after plasma irradiation was measured with a Surfscan 6420 manufactured by KLA-Tencor.

  The discharge conditions are as follows.

[Discharge conditions]
High frequency power: 1500W
Power supply frequency: 13.56 MHz
Processing chamber pressure: 5.32 Pa (4.0 × 10 −2 Torr)
Reaction gas type: C ₄ F ₈ / CO / Ar / O ₂
Table 2 shows the number of solid fine particles adhering to the semiconductor wafer 3 before and after the test.

As is apparent from Table 2, the number of solid fine particles of 0.2 μm or more increased by 115 before and after plasma irradiation in the SiO ₂ material as a comparative example, whereas only 9 increases in the Si ₃ N ₄ material. Not done.

That is, in the case of SiO ₂ material, a large amount of crushed debris is adhered to the surface thereof, so that it is found that a dummy operation of about 5 minutes is insufficient and a dummy operation over a long time is necessary.

On the other hand, since the Si ₃ N ₄ material has a small amount of crushed debris adhering to its surface, the crushed debris adhering to the surface can be removed in a short dummy operation. It has been confirmed that it is possible to quickly shift to the main operation of performing microfabrication.

  A third example corresponding to the second embodiment of the present invention will be described below.

[Third embodiment]
Next, the inventors used a Y ₂ O ₃ material mainly composed of Y ₂ O ₃ as an example of the present invention, and an Al ₂ O ₃ material mainly composed of Al ₂ O ₃ as a comparative example. Insulator ring 40 similar to that of the second example was manufactured.

Next, for the Y ₂ O ₃ material (invention example) under the same discharge conditions as in the _second example, 5 dummy wafers were used for 1 minute each for a total of 5 minutes for dummy operation. _{For the 2} O ₃ material (comparative example), 25 dummy wafers were used for 3 minutes each for a total of 75 minutes of dummy operation, and then a 100-hour running test was performed to fix the 0 0 material on the semiconductor wafer 3. The change with time of the number of solid fine particles of 2 μm or more was measured.

FIG. 6 is a characteristic diagram showing the measurement results, in which the horizontal axis represents the application time (hr) of the high-frequency power, and the vertical axis represents the number of solid fine particles of 0.2 μm or more. In the figure, the solid line indicates the number of solid fine particles generated in the Y ₂ O ₃ material according to the embodiment of the present invention, and the broken line indicates the number of generated solid fine particles in the Al ₂ O ₃ material as a comparative example.

  As is apparent from FIG. 6, in the comparative example, the number of solid fine particles increased rapidly after the application time of about 25 hours, whereas in the embodiment of the present invention, solid fine particles were not generated. It can be seen that it has stabilized at a low level.

That is, Al ₂ O ₃ in the comparative example by reacting with C ₄ F ₈ gas generates AlF _3, said AlF ₃ scatters the plasma atmosphere becomes solid particulates, thereby solid particles semiconductor wafer 3 above It is inferred that it is attached to

On the other hand, in the Y ₂ O ₃ material according to the embodiment of the present invention, solid fine particles are generated but stabilized at a low level, and only about 40 solid fine particles are generated even when the application time has passed 100 hours. Thus, it was confirmed that the generation of solid fine particles was small.

  A fourth example corresponding to the second embodiment of the present invention will be described below.

[Fourth embodiment]
Next, the present inventors made SiC, Y ₂ O ₃ , Si ₃ N ₄ as this example, Al ₂ O ₃ , and SiO ₂ as comparative examples, each having a length of 20 mm, a width of 20 mm, and a thickness of 2 mm. As shown in FIG. 2, the outer peripheral portion 30 of each test piece is masked with a polyimide film (DuPont, registered trademark “Kapton”) as shown in FIG. The plasma was irradiated for 20 hours under the same discharge conditions as in the second embodiment, and the amount of wear (consumption amount) in the X-axis direction and the Y-axis direction was measured with a surface roughness meter.

  FIG. 7 is a bar graph showing the measurement results, in which the horizontal axis represents each ceramic material, and the vertical axis represents the amount of wear (μm) after 20 hours.

As can be seen from FIG. 7, the Si ₃ N ₄ material, the Y ₂ O ₃ material, and the SiC material have less scraping than the SiO ₂ material and are excellent in plasma resistance.

The Al ₂ O ₃ material is superior in plasma resistance as compared with the Si ₃ N ₄ material and SiC material, but as is apparent from the experimental results of the second embodiment, Al ₂ O ₃ is C _Since it reacts with ₄ F ₈ gas to produce solid fine particles composed of AlF _3, it is not suitable as a component material for a plasma processing apparatus.

  A fifth example corresponding to the second embodiment of the present invention will be described below.

[Fifth embodiment]
Next, the present inventors manufactured the insulator ring 40 in the same manner as in the second example using the Si ₃ N ₄ material as the present example and the SiO ₂ material as the comparative example, and the above-described example. The etching rates were compared under the discharge conditions.

FIG. 8 shows the measurement result of the Si ₃ N ₄ material, and FIG. 9 shows the measurement result of the SiO ₂ material. 8 and 9, the horizontal axis represents the wafer diameter (mm) of the semiconductor wafer, and the vertical axis represents the etching rate (nm / min). The measurement was performed on the XY plane of the semiconductor wafer in both the X-axis direction and the Y-axis direction.

Eighth etching rate in Si ₃ N ₄ material diagrams 314nm / min ± 2.1%, the etching rate of SiO ₂ material of the ninth figure next to 302nm / min ± 1.9%, resistance to the Si ₃ N ₄ material Even when used as a plasma component (in-chamber component), it was confirmed that substantially the same etching performance as that of the SiO ₂ material can be secured.

  A sixth example corresponding to the second embodiment of the present invention will be described below.

[Sixth embodiment]
Next, the present inventors made Si ₃ N ₄ -A, Si ₃ N ₄ having a Si ₃ N ₄ purity of 80% by adding yttrium and yttrium as sintering aids to Si ₃ N ₄ in this example. Si ₃ N ₄ purity added ytterbium and yttrium as a sintering aid is 91% Si ₃ N ₄ -B, and Si ₃ Si plus yttrium N ₄ as a sintering aid ₃ N ₄ purity of 98% of _{Si 3 N 4 -C, Si 3} N 4 -D the Si ₃ N ₄ purity of 99.5% plus magnesium as a sintering aid to Si ₃ N ₄ as a comparative example, and the Quartz, longitudinal 20 mm, A test piece having a width of 20 mm and a thickness of 2 mm was prepared. As shown in FIG. 2, the outer peripheral portion 30 of each test piece was masked with a polyimide film (DuPont, registered trademark “Kapton”), An irradiation surface of 10 mm and a width of 10 mm is provided. Plasma was irradiated for 20 hours under the following discharge conditions, and the amount of abrasion (consumption amount) in the X-axis direction and Y-axis direction was measured with a surface roughness meter.

[Discharge conditions]
High frequency power: 1400W
Power supply frequency: 13.56 MHz
Processing chamber pressure: 5.32 Pa (4.0 × 10 ⁻² Torr)
Reactive gas species :: CF ₄ / Ar / O ₂
FIG. 10 is a bar graph showing the measurement results. The horizontal axis represents each ceramic material, and the vertical axis represents the amount of wear when the amount of wear after 20 hours of Quartz is taken as 100.

As is apparent from Figure 10, the scraping amount the Si ₃ N ₄ in ytterbium and Si ₃ N ₄ was added yttrium -A and Si ₃ N ₄ -B as a sintering aid, about the Quartz the scraping amount is 1/3, Si ₃ N ₄ to less than the scraping amount of Si ₃ N ₄ -D plus magnesium as a sintering aid.

Further, Si ₃ N ₄ etching amount of Si ₃ N ₄ -C plus yttrium as a sintering aid is about 60% of the Quartz scraping amount, the magnesium as a sintering aid to Si ₃ N ₄ Less than the amount of Si ₃ N ₄ -D added.

From the above results, the scraping amount is independent of the Si ₃ N ₄ purity by adding a drying aid to the Si ₃ N _4, wear amount is reduced, also as a drying aid, of ytterbium and yttrium It turns out that it is suitable to use at least one of them.

  As described above in detail in the first embodiment, since the plasma processing apparatus component according to the present invention is made of polybenzimidazole (PBI) that has been subjected to a drying process, quartz, PI resin, and PAI resin are used. The plasma resistance is improved compared to the conventional product formed in (1), so that the durability of the components in the chamber can be improved, the maintenance cycle can be extended, and the frequency of component replacement is reduced.

  Moreover, since the plasma processing apparatus component according to the present invention is made of dried polybenzimidazole, moisture does not adhere to products such as semiconductor devices, and therefore it is necessary to perform an extra dummy operation. Disappear.

  In addition, in the method for manufacturing a component for a plasma processing apparatus according to the present invention, a polybenzimidazole powder is subjected to a vacuum drying process and then subjected to a molding process to produce a molded product having a predetermined shape. Therefore, it is possible to easily manufacture a plasma processing apparatus component having excellent plasma resistance and removing water absorption, thereby suppressing variation in the dimension of the BTM (bottom) portion of the etching groove and change over time. Can do.

  Furthermore, it is possible to avoid the occurrence of cracks in the molded product by subjecting the molded product to vacuum drying again at a second drying temperature higher than the first drying temperature set in the vacuum drying process.

  Further, in the plasma processing apparatus according to the present invention, the parts disposed inside the apparatus main body and exposed to the plasma atmosphere are formed of the dried polybenzimidazole, so that the plasma resistance of the parts is Thus improving the durability of these parts. For this reason, since the frequency of parts replacement also decreases, it is possible to improve the productivity of products such as semiconductor devices.

In addition, as described in detail in the second embodiment, the plasma processing apparatus according to the present invention is such that the parts exposed to the plasma atmosphere disposed in the inner wall of the apparatus main body and the processing chamber are made of aluminum. Since it is made of a sintered ceramic material that does not contain any components, it is possible to avoid the occurrence of Al contamination due to the adhesion of impurities such as AlF _{3 to} the surface of the semiconductor product, and to improve the product yield. Can do.

  Further, the sintered ceramic material is selected from one or two or more selected from materials mainly composed of silicon nitride, yttrium oxide, or silicon carbide. Since it consists of seeds or more, so-called dummy operation can be shortened and productivity can be improved.

Moreover, since these sintered ceramic materials are also superior in plasma resistance compared to quartz (SiO ₂ ), durability can be improved, and therefore the frequency of component replacement is reduced, and maintenance is improved.

  In addition, since at least one of yttrium and yttrium is added as a sintering aid to these sintered ceramic materials, the plasma resistance can be further improved, thereby further improving the durability. be able to.

  Further, as described in detail in the third embodiment, the plasma processing apparatus component according to the present invention is a plasma processing apparatus component used for an insulating component disposed inside the apparatus main body of the plasma processing apparatus. Since silicon oxide is contained as a main component and a predetermined different material other than silicon oxide is added, by selecting a material excellent in plasma resistance as the predetermined different material, A component for a plasma processing apparatus having excellent plasma resistance can be manufactured, whereby durability of the component can be improved and productivity of semiconductor manufacturing can be improved.

  In addition, a method for manufacturing a plasma processing apparatus component according to the present invention is a method for manufacturing a plasma processing apparatus component used for an insulating component disposed inside an apparatus main body of a plasma processing apparatus. A predetermined dissimilar material other than silicon oxide is added, the silicon oxide and the dissimilar material are melted under an oxyhydrogen flame, and then cooled to manufacture a part for a plasma processing apparatus. The material can be reliably mixed uniformly, and a desired plasma processing apparatus component having excellent plasma resistance can be obtained.

  In addition, as the dissimilar material, a material containing one or more selected from rare earth compounds, silicon compounds other than the silicon oxide, and aluminum compounds is selected. Can be easily improved.

Ru internal structure view showing an embodiment of a plasma etching apparatus as a plasma processing apparatus according to the present invention. Ru Figure der for explaining a method of measuring the abrasion amount (consumption). Ru bar der showing evaluation results of the plasma resistance of various ceramic materials in the first embodiment. Ru flowchart der processing and washing steps of the PBI. FIG. 5 (a) is a characteristic diagram showing the change over time of the BTM (bottom) dimension of the etching groove when using a PBI resin in which the water content is suppressed to 370 ppm. FIG. 5 (b) Ru characteristic view showing the time course of BTM (bottom) dimensions of etched grooves when water content using PBI resin is 2240Ppm. Ru characteristic view showing the change over time of the solid particles to be fixed on the semi-conductor wafer. Ru bar der showing evaluation results of the plasma resistance of various ceramic materials in the second embodiment. Ru etching characteristic diagram der when using the Si ₃ N ₄ material as off Okasuringu. Ru etching characteristic diagram der when using SiO ₂ material as off Okasuringu. Ru bar der showing evaluation results of the plasma resistance of various ceramic materials in the sixth embodiment. An object diagram showing a manufacturing method of a plasma processing apparatus component material in the third embodiment.

Explanation of symbols

1 Plasma etching system
2 Lower electrode
3 Semiconductor wafer
16 Upper electrode
22 treatment room
101 crystal powder
103 mixture
105 ingot case
106 Parts material

Claims (5)

Was subjected to vacuum drying process in powder polybenzimidazole, to produce a predetermined shape of the molded article is subjected to forming process to the powder which is vacuum dried, when machining after the molding process, 280 ° C. to 300 production of ° C. first annealing and 340 ° C. to 360 ° C. the second component characteristics and to pulp plasma processing apparatus that performs the annealing treatment carried out 2-4 hours at a temperature of performing 2-4 hours at a temperature of Method.   2. The plasma processing apparatus component according to claim 1, wherein the molded product is again vacuum-dried at a second drying temperature higher than the first drying temperature set in the vacuum drying. Method.   The method for manufacturing a component for a plasma processing apparatus according to claim 1 or 2, wherein the vacuum drying treatment is performed at a temperature of 140 ° C to 180 ° C for 5 to 7 hours. 4. The method of manufacturing a component for a plasma processing apparatus according to claim 1 , wherein the second annealing process is performed once after the first annealing process is performed twice. 5. After washing treatment after the machining, plasma processing apparatus according to any one of claims 1 to 4, characterized by applying vacuum drying process performed 2 to 4 hours at a temperature 200 ° C. to 250 DEG ° C. A manufacturing method for parts.

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