JP2006342364A - Method for surface-treating carrier member for machining semiconductor, and surface-treated article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an article which is a machining carrier to be used for extremely thinning and extremely smoothing a semiconductor made from a material such as silicon, gallium nitride and gallium phosphorus, and has a high-quality DLC film having a gradient structure caused by carbon ion implantation coated thereon so as to enhance its quality. <P>SOLUTION: A carrier member for machining a semiconductor has a DLC film formed thereon after the base material has been implanted with carbon ions through a plasma-based ion implantation/film-forming process comprising the steps of: introducing a gas of a hydrocarbon compound having at least one carbon atom into the vacuum atmosphere in the apparatus; generating plasma by supplying a high-frequency power to the apparatus; and applying a high-frequency pulse voltage onto the article to be treated. The surface treatment method includes the above process. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a surface treatment with improved wear resistance, corrosion resistance, and contamination resistance of a polishing semiconductor processing carrier member for ultra-smoothing the surface of a compound semiconductor such as a silicon wafer, gallium phosphide, gallium arsenide, and gallium nitride. It relates to a method and its articles.

  High-precision devices such as silicon wafers are used for high-speed and large-capacity digital information processing represented by personal computers, mobile phones, liquid crystal digital televisions, digital cameras, car navigation devices, and broadband information terminals. The material wafer tends to become thinner and thinner, and there is a demand for an ultra-flat surface with higher precision than before.

As a method for polishing an ultra-thin wafer, a lapping process or a polishing process is often employed. These are a lapping process in which a rough cut workpiece is set on a processing carrier provided with a predetermined circular hole, and then rotated and polished while quantitatively supplying a polishing liquid called slurry, and diamond fine particles are cast, Hard polishing process that pushes and rotates and polishes into a platen embedded in a relatively soft metal such as copper or tin, and also a polishing liquid (chemically active liquid) containing fine abrasive grains in a soft material such as cloth or urethane sponge There is a soft polishing processing method in which a mirror polishing is performed while rotating while supplying a fixed amount.

In polishing these semiconductor wafers, it is necessary to improve the processing accuracy of various polishing devices to the utmost, such as a cast housing that suppresses vibrations of the device as much as possible and has excellent vibration damping by the drive transmission unit. In addition, the processing accuracy, wear resistance, corrosion resistance, and contamination resistance of the carrier jig (hereinafter referred to as semiconductor processing carrier material) for fixing and rotating the wafer is increasingly required. .

Various semiconductor substrates such as stainless steel, titanium alloys, and glass epoxy resin plates are used for current semiconductor processing carrier materials. During the polishing of silicon single crystal plates, metal elution from the substrate, the substrate itself Damage to the carrier member, such as damage due to friction and wear, wear of the rotating gear, and corrosion of the metal, has a significant effect on the polishing process of the ultra-thin wafer. For this reason, the present situation is that the semiconductor processing carrier member is replaced every several hundred hours and used for high quality.

Conventionally, a method of forming a diamond-like carbon film (hereinafter referred to as a DLC film) has been proposed in order to impart slipperiness to the metal material surface or the ceramic material surface. A method of forming a carbon film by a plasma CVD method using raw materials such as methane gas and acetylene gas on the surface of a member that slides with a machine part or a contact member has already been put into practical use, such as a video tape capstan roller, a small bearing, Excellent performance such as hot / cold switching valve.

Reference is made to patent documents described in the following publications.
In the plasma CVD method disclosed in JP-A-2000-96233, the plasma generation method, applied voltage, gas composition, etc. have been devised to develop a plasma CVD apparatus capable of processing at as low a temperature as possible. In addition, a method for forming a DLC film has been proposed, and further, it has been proposed to use it for camera O-rings, automobile wiper rubber, and the like. However, these plasma CVD methods are methods in which the introduced gas is turned into plasma at a high frequency, and the activated carbon element is chemically reacted and deposited on the surface of the component. Therefore, the chemical reaction between the member surface and the DLC film layer is performed. Bonding strength is weak and adhesion may be poor.

In particular, in order to process a heat-sensitive material such as a plastic material or rubber, it is necessary to generate a soft plasma by modulating a high frequency in order to reduce (weaken) the plasma density. In order to attract carbon ions in the plasma, it is common to apply a bias voltage of several tens of volts to several hundreds of volts. However, with such a voltage, the carbon element is attached to the surface layer portion of the substrate. Therefore, it is not possible to implant ions into the base material (several tens of nm or more). Therefore, in the plasma CVD method, in order to improve the adhesion to the base material, silicon as a base treatment layer, silicon oxide, silicon nitride, silicon carbide, titanium tetrachloride, pentaethoxytitanium, tetraisoproxytitanium, etc. are used. It is necessary to improve the adhesion to the substrate by introducing an intermediate layer of a compound of silicon or titanium and carbon.

Also, in the PVD method (physical vapor deposition method) that forms a film by sputtering a carbon solid target, a DLC film is formed by heating the substrate temperature of metal or ceramic at 300 to 500 ° C. in order to improve adhesion. In addition, it was necessary to form a film by depositing silicon or chromium material, which is compatible with carbon, as a base treatment. Further, in order to attract carbon ions in plasma, it is common to apply a DC or AC bias voltage of several tens of volts to several hundreds of volts. This voltage is used as film forming energy, It is not possible to greatly improve the adhesion.

Furthermore, it is necessary to provide a device with a special reaction mechanism in order to uniformly apply the base, and a rotation mechanism is indispensable in order to ensure the uniformity of the film thickness. It could only deal with products with a certain shape. In particular, the semiconductor processing carrier member to be processed in this proposal consists of a high-precision disk having a large area ranging from 500 to 800 mm in diameter and 0.5 to 0.8 mm in thickness, and the DLC film is uniformly controlled with a 0.1 μm system on this surface. It is necessary to form a film.

  In the above plasma CVD method, if the area is large, the plate material is distorted and processing accuracy cannot be obtained. In the PVD method, even if a DLC film is formed by providing a rotation mechanism, the film thickness cannot be made uniform and 1 μm. The above thickness variation occurred. Furthermore, the film forming process has become complicated in both cases, and the processing cost has increased.

With the above-described technology, it is difficult to uniformly form a DLC film on a semiconductor processing carrier member, and a process capable of forming a DLC with high accuracy, low cost, and uniformity without requiring a complicated rotation mechanism has been desired.

In the present invention, a surface layer of a semiconductor processing carrier member composed of a high-precision disk having a large area ranging from 500 to 800 mm in diameter and 0.5 to 0.8 mm in thickness is surface-modified using a plasma-based ion implantation technique. A new DLC film formation process and high-quality DLC-coated semiconductor processing carrier that cannot be formed by physical film formation process (PVD) or chemical film formation process (CVD). A member is provided.

  A conventional diamond-like carbon film, or DLC film, has high hardness, excellent wear resistance, electrical insulation, hydrophilicity, etc., and the carbon content varies depending on the film formation method and raw materials used, and has various hardness. A membrane was obtained. In particular, the plasma CVD method, the sputtering method, the ion plating method, etc. have high hardness and excellent wear resistance, but they are not suitable because they have poor adhesion to the base material. The method is applied to the surface of semiconductor processing carrier members that are composites of various metal materials, ceramic materials, plastic molding materials, etc., and is provided as a surface modification technology with improved wear resistance, corrosion resistance, and contamination resistance. .

  The present invention uses plasma-based ion implantation / film formation to generate RF plasma by an external antenna or a self-bias voltage around a semiconductor processing carrier member (base material), and several hundred volts to this. By applying a negative pulse voltage of several tens of kV and injecting ions containing carbon into the surface of the molded product, a carbon gradient layer is formed, and further, a DLC film containing carbon and hydrogen is formed while controlling the voltage. In this way, the above-mentioned problems can be solved and the object can be achieved.

Semiconductor processing carrier members are not a single material, but are mostly members composed of a metal disc part such as stainless steel or titanium alloy and a resin gear part such as polyimide resin, polyamideimide resin, polyetheretherketone resin or nylon resin. Or a composite member in which disk members such as glass fiber reinforced epoxy resin and carbon fiber reinforced epoxy resin are combined. For this reason, it is necessary to form a DLC film under conditions that allow a metal or plastic film to be formed.

Specifically, surface modification of semiconductor processing carrier members using equipment configured in a vacuum chamber, vacuum exhaust system, gas supply / treatment system, high-frequency plasma source, negative high-voltage pulse power supply / high-pressure introduction system and cooling system do. Power can be supplied by simply connecting an electrode lead wire to a metal, but an insulator for ceramics, rubber, plastic, etc. is provided with an electrode for applying a voltage on the back or in the center to supply power to a high-frequency plasma source. When a negative high voltage pulse voltage is applied around the injection target (metal, plastics) by supplying a gas plasma, electrons in the plasma are expelled, and ions are scattered around the outline of the injection target. A sheath is formed. The ion sheath is covered along the contour of the implant, and then a negative voltage is applied to the ion sheath, so that only ions are attracted and accelerated from all directions to the implant and aim at the implant. Elements are ion-implanted.

  In the present invention, carbon ions can be implanted into insulators such as metals and plastics. Conventionally, since positive ions are implanted by applying a DC bias voltage, there is a case in which an insulator is charged and causes a breakdown due to a charge-up charge. In the method of applying a high-frequency, high-voltage negative pulse voltage according to the present invention, since the pulse is a pulse, the plasma approaches the base material when there is no pulse voltage, the charge charged on the base material is released into the plasma, and the charge-up is eliminated. The Further, by optimizing the pulse frequency and application time for each shape, it is possible to prevent dielectric breakdown and to prevent film non-uniformity and film formation rate decrease due to charge-up.

  It is as follows.

Parameters affecting the characteristics of plasma-based ion implantation and deposition include the frequency of the high-frequency plasma source, plasma amplification voltage, repetition frequency, number of pulses, etc., and parameters on the high-voltage induced pulse power supply side include applied voltage and current current. The number of repetitive pulses, the pulse width, the delay time, etc., and the gas flow rate, gas pressure, etc. of the plasma generation raw material have an effect. By controlling these, an ion sheath is formed along the contour of the injection target, and only ions are injected into various metals, ceramics, and plastic moldings that are the injection target, thereby providing wear resistance and corrosion resistance. The present invention provides a method for coating a surface of a semiconductor processing carrier member with a DLC film having improved contamination resistance and a coated article thereof.

  The hydrocarbon gas used here is a gas mainly composed of at least one selected from hydrocarbon compounds consisting of methane, acetylene, benzene, toluene, cyclohexanone, chlorobenzene, etc., and introduced into the vacuum chamber. Then, it is preferable to generate a carbon atom or a molecular ion by applying a high frequency voltage to turn the gas into a plasma, and accelerating the ion to perform ion implantation.

  As a method for selecting a hydrocarbon-based gas, the plasma state varies depending on the ratio of carbon atoms and hydrogen atoms, and it is preferable to determine the gas species and the mixing ratio thereof depending on what percentage of hydrogen atoms are contained in the DLC film. . In methane, acetylene, benzene, and toluene gases, it is known that the degree of carbon ion implantation and the state of film formation of the DLC film vary greatly depending on whether aliphatic or aromatic, and carbon difluoride as required. , Carbon tetrafluoride, carbon hexafluoride, sulfur hexafluoride, tetradecafluorocarbon, etc. to add DLC film with functions such as lubricity and water repellency. It is desirable to select.

  The high frequency power for generating the gas plasma is desirably a pulse width of 1.0 μsec or more in a frequency range of 0.2 MHz to 2.45 GHz and an output range of 10 W to 20 kW. The reason is that if the frequency is lower than 0.2 MHz, the plasma decomposition of the gas is not sufficient, and the deposition rate does not increase. If the frequency is higher than 2.45 GHz, the stability of plasma generation and the cost of the apparatus increase. Because. This is because if the high-frequency output is 10 W or less, the plasma density is low and film formation cannot be performed even if ion implantation is possible, and if it is 20 kW or more, the power supply capacity is large and the apparatus cost is increased. Further, when the pulse width is 1.0 μsec or less, the substantial ion implantation time is shortened, and in the case of an insulator, it is easy to charge up.

Furthermore, not only the above plasma generation but also a high frequency pulse application power source is very important. In the conventional mass separation type ion implantation, it is possible to inject only carbon ions after being excited by an electric field using a commercially available gas such as methane or acetylene. However, in the plasma method, a negative high voltage is applied to various substrates in a pulsed manner, and molecular ions bonded to carbon are also simultaneously implanted as impurities. The inventors of the present application have found that the following high-frequency pulse application conditions are suitable as a result of various investigations of favorable plasma conditions that can sufficiently inject carbon ions even in the presence of these extra ions.

As the high-frequency pulse applied voltage, it is necessary to optimize the frequency, pulse width, and applied voltage. The reason is that if the frequency is 100 Hz or less, the number of ion implantations within a certain period of time decreases, and the ion implantation efficiency decreases. On the other hand, when the frequency is 5000 Hz or higher, it is necessary to improve the performance of the high-frequency pulse power source, which causes an increase in the device cost. The pulse width is greatly related to the sheath width at the time of ion implantation. If the width is narrow, the sheath is formed along a complicated shape and is uniformly implanted, but if the width is wide, the sheath cannot be formed in the narrow gap. The injection volume is reduced. For this reason, if the pulse width is 1.0 μsec or less, the ion implantation efficiency of one pulse is shortened, so that the ion implantation efficiency is lowered, and an expensive high-frequency power source is required to form a nanosecond order pulse width. The equipment cost increases. On the other hand, when the pulse width is wide and 1000 μsec or more, the plasma density supplied to the periphery of the molded product is lowered, and not only the ion implantation efficiency is lowered, but also high performance of the pulse power source is required, resulting in an increase in apparatus cost. Become.

A particularly preferable negative pulse voltage is preferably -1.0 to 30 kV from the viewpoint of adhesion of the substrate, wear resistance, and corrosion resistance. The ion implantation depth to the substrate is shallow when it is −1.0 kV or less, the inclined structure between the substrate and the carbon film is not obtained, and it does not contribute to the improvement of the adhesion, and the high voltage is −30 kV or more. In this case, the inclined structure between the base material and the DLC film will progress, but the high-frequency pulse power supply will increase in size, leading to a significant increase in equipment cost. Generation of distortion of the product becomes remarkable, and 30 kV or more is not preferable.

  Although the ion implantation time to the surface of various base materials is not limited, it is preferably 30 to 120 minutes. More preferably, it is a short time treatment from the viewpoint of productivity, but in the plastic molding part of the semiconductor processing carrier member, the surface layer becomes brittle due to the carbon element injection, and the adhesion may be lowered. Must be selected.

  In conventional ion implantation by mass separation, the implantation current is less than mA, and in the case of high energy, it is on the order of several A. Therefore, it takes several hours to perform ion implantation of 1E17 ions / cm 2. On the other hand, in plasma-based ion implantation, a current flows into the molded product from the periphery at a time, and therefore, a current of several A to several tens of A flows, thereby enabling carbon ion implantation processing in a short time. In addition, since the ion implantation is performed not by direct current but by pulse, damage to the insulator due to charge-up is very small.

In the carbon ion implantation method of the present invention, ions are implanted with an energy sufficient to sufficiently penetrate the surface oxide layer, so that it is possible to easily form a carbon gradient structure. It is possible to form a DLC film while increasing the surface hardness by implanting carbon ions at a high energy for non-ferrous metals that are difficult to perform, and also by changing the DLC film formation energy and suppressing the elastic modulus of the DLC film. It is possible. As a result, the residual stress in the DLC film is low and adhesion is easily obtained. For this reason, it is possible to easily obtain a DLC film in the range of 2.0 to 10 μm in a semiconductor processed carrier member that requires wear resistance.

In addition, when a wafer is polished using a highly corrosive silicon polishing solution, it is necessary to perform DLC film formation that emphasizes corrosion resistance. In a sputtering film forming method in which a conventional graphite target is used as a raw material, carbon particles called droplets are present in the DLC film or a large number of minute pinholes are generated, resulting in a significant loss of corrosion resistance. In the carbon ion implantation + DLC film forming method of the present invention, an arbitrary amount of carbon can be implanted to easily form a carbon gradient structure, and the upper carbon layer is ionized by plasma decomposition of hydrocarbons. Since it is an amorphous carbon deposit obtained by recombining only the carbon that has been formed, a very dense DLC film without droplets or pinholes can be formed.

In this process, since it is possible to form the film while suppressing the elastic modulus of the DLC film by changing the energy at the time of forming the DLC film, the residual stress in the carbon film is low and the adhesion can be easily obtained. For this reason, it is possible to easily obtain a carbon film having a thickness of 2.0 to 10 μm, and for a semiconductor processing carrier member comprising a high-precision disk having a large area ranging from 500 to 800 mm in diameter and a thickness of 0.5 to 0.8 mm. It was found that the DLC film can be uniformly formed with an accuracy of 0.5 μm or less without being affected by the residence strain, and this process was found to be optimal.

In the DLC film-formed semiconductor processing carrier member of the present invention, carbon is ion-implanted by 10 nm or more from the surface of the non-processed object, and a hard DLC layer is formed at least 1.0 to 10 μm on the surface layer portion. It is said. In the conventional plasma CVD method, PVD method, etc., in order to attract carbon ions in the plasma, it is common to apply a DC voltage or an AC bias voltage of several tens to several hundreds V. Carbon atoms were not ion-implanted by 10 nm or more from the surface of the object, and it did not contribute to improving the adhesion to the substrate.

As a result of evaluating various changes in high-frequency pulse voltage, pulse width, frequency, loading time, processing temperature, etc., the fact that deeper carbon atoms are implanted from the surface of the workpiece contributes to improved adhesion. I found it. As a result of the experiment, it is preferable that at least 10 nm or more of ions are implanted, and it has been found that if it is shallower than this, the contribution rate to the adhesiveness decreases. The reason for this is thought to be that the residual stress of the carbon film to be formed cannot be relaxed in the tens of atomic layers from the surface layer, and a hundred atomic layers are necessary.

Carbon atoms are implanted deeper than the surface layer portion, and at least a hard DLC film layer formed on the surface thereof has a thickness of at least. When the film is formed to a thickness of 01 to 10 μm, a DLC film having wear resistance, corrosion resistance, lubricity and contamination resistance exhibits a greater effect. In the conventional plasma CVD method, PVD method, etc., it is common to form a carbon film of 0.1 to 2.0 μm due to residual stress generated at the base material interface. The residual stress generated at the substrate interface was reduced by the inclined structure, and the formation of a DLC film of 3.0 μm or more was facilitated. According to experiments, it was found that, for example, a DLC film having a thickness of 50 to 100 μm can be formed on a flexible aluminum substrate, and can be applied as a sliding member having a high function and a long life.

Furthermore, what is important in the semiconductor processing carrier member is that impurities are not eluted during polishing of the silicon wafer. In semiconductor processing carrier members using conventional stainless steel, trace impurities such as iron, chromium and nickel are eluted, which may adversely affect the wafer.
In the semiconductor processing carrier member formed with DLC film according to the present invention, it can be understood that the metal ion elution effect is also effective for reducing the metal elution, and the semiconductor processing carrier in which no elution of impurities is detected by the uniform DLC film formation. It became possible to obtain a member. A carbon ion implantation layer having a thickness of 10 nm or more was formed from the surface layer of the object to be treated of the present invention, and the carbon film was formed on the surface layer higher than the original carbon element concentration by several tens at% or more, thereby performing ion implantation. It is inferred that the base material reduces the interatomic distance and suppresses metal elution.

  In the semiconductor processing carrier member of the present invention, a metal and plastic composite member is attached to a negative voltage application sample stage and integrated with a high voltage feedthrough. Radio frequency (RF) power is applied between the feedthrough and the chamber, and electrons are reciprocated by electric field changes between them, and gas molecules are ionized by repeating collisions with gas molecules to form a high-density plasma. . Since ions, radicals, and electrons coexist in the plasma, if a high voltage pulse voltage is applied, the ions in the plasma can be injected into the metal and plastic composite sample. If the high voltage pulse voltage is not applied, self-bias (normal number) 10 volts) is deposited on the surface, and at this time, carbon elements are bonded by radical polymerization to form a film. Using this superposed plasma ion implantation / deposition apparatus, ion implantation / deposition or a combination of ion implantation and deposition can be performed by controlling RF power and high-voltage pulse power.

  The physical properties of the DLC film vary depending on the type of gas used, the gas pressure, the applied voltage, etc., but a DLC film having excellent adhesion to the substrate, high hardness and a large film thickness is preferred. In the plasma-based ion implantation / deposition apparatus, it is preferable to form a film by a process of at least three steps. After cleaning the substrate surface, ion implantation is performed at a high voltage, and then methane, acetylene, toluene at a voltage lower than the carbon ion implantation voltage. It is preferable to form a DLC film by introducing a gas such as, and then form a DLC film at a lower voltage (several kV). This is because when the DLC film is formed with high energy, the carbon bond is recut, the DLC fine film structure is disturbed, and it is difficult to obtain a hard and high-quality film, and it is difficult to obtain the film formation speed. In particular, it is preferable to form a film with lower energy as the surface layer portion is obtained because a high-quality DLC film can be obtained. Thus, it has been found that the three steps of high energy ion implantation, medium energy DLC film formation, and low energy DLC film formation are useful for relaxation of residual stress in the DLC film and are advantageous for thick film formation.

Embodiments of the present invention will be described below.
First, a schematic configuration of a plasma-based ion implantation / film formation apparatus used in the surface treatment method for various substrates of the present invention will be described with reference to FIG. This apparatus comprises a vacuum chamber 3 containing a frame 2 on which a semiconductor processing carrier member 1 is set. The set stand also serves as an electrode for applying a negative voltage. The inside of the vacuum chamber 3 can be maintained at a predetermined degree of vacuum by the exhaust device 4. In this apparatus, a predetermined hydrocarbon-based gas is introduced through the introduction port 5 to form a hydrocarbon-based gas plasma and, if necessary, ion implantation of a metal-based element to improve the adhesion of the DLC film. An organometallic gas introduction source 6 is also provided.

  The apparatus further includes a high voltage negative pulse power source 7 and a radio frequency (RF) power source 8 for applying a high voltage negative charge to the semiconductor processing carrier member 1 having various shapes. The high voltage negative pulse power source 7 generates a negative charge having a predetermined energy, and applies a negative charge pulse to the semiconductor processing carrier member 1 through the high voltage feedthrough 9. This feed-through is connected to the set frame, and the set frame is in an electrically floating state with an insulator 10. Further, when forming the DLC, it is possible to supply the power from the high-voltage feedthrough 9 through the superimposing device 11 that superimposes the high-voltage pulse and the high frequency to form the supply gas into a plasma. A shield cover 12 is attached to the high voltage feedthrough 9 to protect the feedthrough 9.

  A semiconductor processing carrier member 1 as shown in the A development view of FIG. 1 is set on the set frame 2 of this apparatus. This sets 3 to 9 semiconductor processing carrier members 1 having a diameter of 500 mm and a thickness of 0.7 mm. I can do it. Several holes a for fixing a silicon wafer are opened in the semiconductor processing carrier member 1, and a polyether resin ring 13 is bonded to the outer peripheral portion of the hole. The shape of the hole and the resin material are arbitrarily selected. In addition, in order to correctly evaluate the film thickness after the DLC film is formed on a part of the member, the physical and chemical characteristics of the 10 × 10 × 0.3 mm square silicon wafer (b) and the DLC film-formed product are evaluated. Thus, a 25 × 25 × 2 mm square stainless steel specimen (c) is attached to enable test evaluation.

When a negative charge pulse is applied to these semiconductor processed carrier members, carbon ions in the plasma or ions such as CH, CHx, and C2 are attracted to the semiconductor processed carrier member, and carbon ions or hydrogen ions are implanted. Since ions are implanted by applying a negative charge pulse to the semiconductor processing carrier member, an electric field is generated along the shape of the member, even if the member is not a flat plate but an uneven solid shape, and is almost perpendicular to the surface. Carbon ions collide with each other. Therefore, even if the insulating plastic member has irregularities, carbon ions can be implanted into the entire plastic surface. At the same time, hydrogen ions are also ion-implanted, but it is known that hydrogen in the base material diffuses and degass after injection, and it is considered that the physical properties of the base material are not greatly affected. .

A DLC film is continuously formed after carbon ion implantation. Carbon ion implantation is performed at a voltage of several kV or more, preferably 10 kV or more, but the DLC film is formed by mixing a mixture of hydrocarbon gases such as methane, acetylene, benzene, and toluene at an arbitrary ratio of 10 kV or less. The film is formed while applying a voltage of. This is because when the DLC film is formed at a high energy, the film structure of the DLC is disturbed by the collision energy of ions, and it is difficult to obtain a hard and high-grade film, and it is difficult to obtain a film formation speed. In particular, it is preferable to form a film with lower energy as the surface layer portion is obtained because a high-quality DLC film-coated article can be obtained. It is preferable to use a film forming technique in which the voltage is gradually lowered from the high voltage side to the low voltage side by automatic control during film formation.
This will be described below based on examples.

(Experimental example l)
Using a plasma-based ion implantation / film formation apparatus as shown in FIG. 1, test pieces b and c for analysis are placed beside the hole a provided in the semiconductor processing carrier member 1 as shown in the A development view in FIG. A large number were pasted and used for analysis evaluation. In the experiment, plasma was generated under the following conditions, and carbon ion implantation + carbon film was formed and evaluated.

Material used: Stainless steel (SUS304 made by Nippon Steel & Sumikin Stainless Steel)
Use gas type: Methane gas / acetylene mixed gas mixing ratio: Methane gas 50 / acetylene 50
Pressure during injection / film formation: 0.5 Pa to 1.0 Pa
Injection energy: 10 keV, 20 keV, 30 keV
Deposition energy: 10 keV → 2 keV
Injection time: 30 minutes Carbon film formation time: 180 minutes Application frequency: 2000 Hz

  Carbon ions were implanted into stainless steel with the energy of the above three conditions, and then a DLC film was formed using a methane / acetylene mixed gas while lowering the voltage. Since the pressure at the time of film formation fluctuates when the negative voltage or the film formation energy is changed, the pressure range at that time is shown, and the arrow of the film formation energy indicates that the experiment was performed while the voltage was reduced within the film formation time. The distribution of the implanted carbon element in the depth direction was evaluated by an Auger analyzer (AES), and the carbon implantation depth and the amount (Atomic Concentration (%)) were obtained. Further, the hardness and adhesion of the stainless steel substrate surface were measured with a dynamic hardness meter and a scratch adhesion evaluation tester, and the friction coefficient was measured with a steel ball in a friction test by a ball and disk method. The DLC film thickness was determined by obtaining the DLC film thickness adhered to the silicon wafers affixed to the semiconductor processing carrier member nine by nine, and evaluating the variation of the DLC film thickness. For AES analysis, the carbon injection distribution at injection energies of 10 keV, 20 keV, and 30 keV is shown in FIG. The hardness, adhesion, and friction coefficient are shown in FIG. 3 in comparison with untreated stainless steel.

  The horizontal axis in FIG. 2 indicates the depth direction of the stainless steel material, the origin indicates the DLC film material, and the vertical axis indicates the ratio of the carbon element in the material. In the analysis, the DLC film was analyzed after thinning it beforehand by argon sputtering. As can be seen from FIG. 2, the carbon layer, which is the main component of the DLC film, is formed on the stainless steel surface up to about 300 nm, and the vicinity of 330 nm is seen as the outermost layer portion of the stainless steel. From this, it can be seen that the carbon injection layer is a high-concentration carbon layer from 380 nm to about 450 nm. As a result, it can be seen that the higher the implantation energy, the deeper the carbon penetration depth, and the ion implantation into the interior. It can be seen that the carbon implantation depth is about 10 nm at 10 keV, 90 nm at 20 keV, and 120 nm at 30 keV. This shows that the higher the applied voltage before forming the DLC film, the deeper the carbon penetrates into the stainless material, indicating an inclined structure.

On the other hand, as shown in FIG. 3, the dynamic hardness, scratch adhesion and friction coefficient of the stainless steel surface are very soft with a hardness of 570 for the untreated stainless steel. It can also be seen that the scratch adhesion is 15 N or more even though the substrate is soft. Stainless steel exhibited a very high coefficient of friction of 0.3 or more, but all of the DLC films exhibited a low coefficient of friction of 0.18 or less. Looking at the relationship with the ion implantation energy, it was found that at a suitable implantation energy, the hardness was high and the friction coefficient was low.
Further, as a result of evaluating the uniformity of the DLC film thickness as a semiconductor processing carrier member, as a result of measuring nine points on each of six semiconductor processing carrier members as shown in FIG. It was found that DLC film formation was possible with an error range of 3 μm.

(Experimental example 2)
Using the plasma-based ion implantation / film formation apparatus as shown in FIG. 2, the test pieces b and c for analysis are placed beside the hole a provided in the semiconductor processing carrier member 1 as shown in the A development view in FIG. A large number were pasted and used for analysis evaluation. In the experiment, plasma was generated under the following conditions, and carbon ion implantation + carbon film was formed and evaluated.

Material used: Titanium alloy material (KS6-4 manufactured by Kobe Steel, Ltd.)
Gas type used: Acetylene / toluene gas mixture ratio: Acetylene 70 / toluene 30
Pressure during injection / film formation: 0.5 Pa to 1.0 Pa
Injection energy: 10 keV, 20 keV, 30 keV
Deposition energy: 10 keV → 2 keV
Implantation time: 30 minutes Carbon film formation time: 180 minutes Application frequency: 3000 Hz

  Carbon ions were implanted into the titanium alloy with the energy of the above three conditions, and then a DLC film was formed using an acetylene / toluene mixed gas while lowering the voltage. Since the pressure at the time of film formation fluctuates when the negative voltage or the film formation energy is changed, the pressure range at that time is shown, and the arrow of the film formation energy indicates that the experiment was performed while the voltage was reduced within the film formation time. The distribution of the implanted carbon element in the depth direction was evaluated by an Auger analyzer (AES), and the carbon implantation depth and the amount (Atomic Concentration (%)) were obtained. Further, the hardness and adhesion of the titanium alloy substrate surface were measured with a dynamic hardness meter and a scratch adhesion evaluation tester, and the friction coefficient was measured with a steel ball in a friction test by a ball and disk method. The DLC film thickness was determined by obtaining the DLC film thickness adhered to the silicon wafers affixed to the semiconductor processing carrier member nine by nine, and evaluating the variation of the DLC film thickness. For AES analysis, the carbon injection distribution at injection energies of 10 keV, 20 keV, and 30 keV is shown in FIG. Further, the hardness, adhesion, and coefficient of friction are shown in FIG. 6 in comparison with an untreated titanium alloy.

  The horizontal axis of FIG. 4 indicates the depth direction of the titanium alloy material, the origin indicates the DLC film material, and the vertical axis indicates the ratio of the carbon element in the material. In the analysis, the DLC film was analyzed after thinning it beforehand by argon sputtering. As can be seen from FIG. 4, the carbon layer, which is the main component of the DLC film, is formed up to around 330 nm on the titanium alloy surface, and around 340 nm is seen as the outermost layer portion of the titanium alloy. From this, it can be seen that the carbon injection layer is a high concentration carbon layer from 420 nm to around 540 nm. As a result, it can be seen that the higher the implantation energy, the deeper the carbon penetration depth, and the ion implantation into the interior. It can be seen that the carbon implantation depth is about 10 nm at 10 keV, about 160 nm at 20 keV, and about 200 nm at 30 keV. This shows that the higher the applied voltage before forming the DLC film, the deeper the carbon enters the titanium material, indicating a tilted structure.

On the other hand, as shown in FIG. 5, the dynamic hardness, scratch adhesion and friction coefficient of the titanium surface are very soft with an untreated titanium alloy having a hardness of 320. However, by forming a DLC film, the hardness is 1100 or more. In addition, it can be seen that the scratch adhesion is 12 N or more even though the substrate is soft. Titanium alloys showed a very high friction coefficient of 0.4, but both showed low friction coefficients of 0.16 or less by the DLC film. Looking at the relationship with ion implantation energy, it was found that the hardness tends to be slightly lower at higher energies.
Furthermore, as a result of evaluating the uniformity of the DLC film thickness, as a result of measuring 9 points on each of 6 semiconductor processed carrier members as shown in FIG. 5, an error of ± 0.3 μm with respect to the average film thickness of 2 μm. It was found that DLC film formation was possible within the range.

Although not described in the experimental examples, the same experiment and evaluation were performed with respect to the glass epoxy substrate. As a result, carbon ion implantation was confirmed up to about 130 nm with 10 keV energy, and a DLC film formed with acetylene / toluene. It was found that the physical properties after formation showed the same surface physical properties as titanium alloys. Thus, it became clear that pulse ion implantation of carbon regardless of metal or insulator and subsequent DLC film formation are indispensable.

As described above, according to the method of the present invention, carbon ion implantation is performed from a hydrocarbon-based gas plasma to a semiconductor processing carrier member using a plasma-based ion implantation / film formation method, and at least a hydrocarbon gas is added. It has been found that by forming a DLC film while mixing and introducing one or more kinds, it is possible to provide a DLC-coated article excellent in wear resistance, corrosion resistance, and contamination resistance of a semiconductor processed carrier member and a surface treatment method thereof.

Further, the DLC-coated article of the present invention has high surface hardness due to carbon ion implantation, and has excellent wear resistance, corrosion resistance, and contamination resistance. Therefore, an aluminum magnetic disk substrate other than a semiconductor, a glass magnetic disk substrate, It can also be used for polishing photomask glass substrates, crystal oscillators, optical lenses, and reflecting mirrors. Furthermore, the carbon ion implantation + DLC film formation technology of the present invention can increase lubricity, water repellency, and release properties in addition to wear resistance, corrosion resistance, and contamination resistance. The present invention can also be applied to industrial ceramic materials and metal material molded products such as increasing the surface hardness of ceramic materials and improving the functionality of lubricity and releasability.

It is the block diagram and member shape figure of the plasma base ion implantation and film-forming apparatus used for the semiconductor processing carrier member of this invention. It is a graph which shows the relationship between the carbon implantation depth by the Auger analysis after carbon ion implantation + DLC formation to SUS304, and carbon concentration. It is a table | surface which shows physical changes, such as the hardness after carbon ion implantation + DLC formation to SUS304, adhesion, and a friction coefficient, and film thickness distribution. It is a graph which shows the relationship between the carbon implantation depth by the Auger analysis after carbon ion implantation + DLC formation to a titanium material, and carbon concentration. It is a table | surface which shows physical changes and film thickness distribution, such as the hardness after carbon ion implantation to DLC + DLC formation, adhesive force, and a friction coefficient.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor carrier member 2 Base 3 Vacuum chamber 4 Exhaust device 5 Hydrocarbon gas inlet 6 Organometallic gas inlet 7 High voltage negative pulse power source 8 High frequency (RF) power source 9 High voltage feedthrough 10 Insulator 11 Superimposing device 12 Shield cover

Claims (9)

Carbon gas plasma is generated in a vacuum of 0.1 to 10 Pa, and a semiconductor processing carrier member made of stainless steel, a titanium alloy, a glass epoxy resin material or the like is exposed therein, and the semiconductor processing carrier member is exposed to 1 to 50 keV, 100 to 100- A method for treating a surface of a semiconductor processed carrier member, comprising applying a high voltage negative pulse of 5000 cycles to inject carbon ions into the surface of the semiconductor processed carrier member. A non-processed semiconductor processing carrier member is set in a vacuum of 0.1 to 10 Pa, and a hydrocarbon gas is introduced therein to generate plasma by supplying high-frequency power. , A high-pressure negative pulse of 500 to 5000 cycles is applied, and carbon ions are ion-implanted from the surface of the semiconductor-worked carrier member, and then a diamond-like carbon layer is deposited on the surface layer. . As a hydrocarbon gas, a gas mainly composed of at least one selected from gases consisting of methane, acetylene, benzene, toluene, cyclohexanone, chlorobenzene, carbon difluoride, carbon tetrafluoride, etc. is used. 3. The method of surface treatment of a semiconductor processing carrier member according to claim 2, wherein a DLC layer is formed after carbon ions are implanted. 3. The surface treatment method for a semiconductor processed carrier member according to claim 2, wherein at least an applied voltage to the semiconductor processed carrier member is 10 keV or more and a carbon ion implantation time is 30 to 120 minutes. The semiconductor processing carrier member is mainly composed of a composite member in which a metal part such as stainless steel or titanium alloy is combined with an engineering resin such as polyimide resin, polyamideimide resin, polyetheretherketone resin, nylon resin or glass epoxy resin. A surface treatment method for a semiconductor processing carrier member according to any one of claims 1 to 4. 6. The surface treatment method for a semiconductor-worked carrier member according to claim 5, wherein a carbon ion implanted layer is ion-implanted 10 nm or more from a member surface layer into a member mainly composed of a metal and an engineering resin. 7. The semiconductor processing carrier member according to claim 1, wherein carbon ion implantation is performed on a member mainly composed of a metal and an engineering resin, and a carbon concentration inside the member surface layer is 10 at% or more. Surface treatment method. 2. The semiconductor processing according to claim 1, wherein after the carbon ions are implanted into the surface of the semiconductor processing carrier member, a diamond-like carbon layer is continuously formed at least 1 μm or more so that the surface friction coefficient is 0.18 or less. A surface treatment method for a carrier member. A semiconductor processed carrier article manufactured using the method according to claim 1.

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