JP2005213636A - Combined film deposition apparatus and sputtering vapor source - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combined film deposition apparatus and a sputtering vapor source by which a hard coating having desired characteristics can be obtained without causing problems about film deposition. <P>SOLUTION: The apparatus for depositing the film is equipped with each one or more arc vapor sources 5, 6 and sputtering vapor sources 2, 3 having a magnetic field applying mechanism 4 disposed in one film depositing chamber 8, and the apparatus is equipped with a means which successively and relatively moves a substrate 1 where a film is to be deposited between the arc vapor sources 5, 6 and the sputtering vapor sources 2, 3. The magnetic field applying mechanism 4 is constituted in such a manner that the magnetic force lines 10 of the vapor sources adjacent to each other are connected to each other while depositing a film. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a composite film forming apparatus that includes an arc evaporation source and a sputtering evaporation source, and can form a hard film or the like having excellent characteristics, and a sputtering evaporation source for a composite film forming apparatus. The present invention can also be applied to the formation of a film other than a hard film as an abrasion-resistant film, but the following description will be focused on the formation of a hard film.

  In order to improve the wear resistance of a cutting tool based on cemented carbide, cermet or high-speed tool steel or a sliding member for automobiles, a wear-resistant film is provided on the surface of these members.

  As this wear-resistant film, conventionally, a hard film such as TiN, TiCN, or TiAlN which is a composite nitride film of Ti and Al is coated on the substrate.

  These wear-resistant hard coatings are generally composed of hard coatings in which thin films made of the same or different hard materials are repeatedly laminated in layers. For the formation of such a multilayer hard coating, each hard coating layer is formed on a substrate by combining a plurality of arc evaporation sources, sputtering evaporation sources, or electron beam evaporation sources according to the hard material. There are devices or methods to do this.

  Among these, an apparatus that forms a hard coating layer on a substrate by combining a plurality of arc evaporation sources or sputtering evaporation sources, respectively, or sequentially forms a film by utilizing different characteristics of the arc evaporation source and the sputtering evaporation source. In this respect, it can be said that the film forming efficiency is high.

  For example, when comparing the characteristics of an arc evaporation source and a sputtering evaporation source, arc evaporation has a higher film formation rate than sputtering evaporation, but it is difficult to adjust the film formation rate, and the thickness of the thin film layer is accurately controlled. It is difficult. In contrast, the sputtering evaporation source has a slower film formation rate than the arc evaporation source, but it is easy to adjust the film formation rate and operates with a very small input power. There is a characteristic that can be controlled accurately.

  Therefore, if an arc evaporation source is used for a relatively thick film layer and a sputtering evaporation source is used for a relatively thin film layer, the thickness of each film layer can be easily controlled, and the overall film formation rate can be increased. Can do.

  As a composite film forming apparatus in which a plurality of arc evaporation sources and sputtering evaporation sources are combined, a film forming apparatus in which a plurality of arc evaporation sources and sputtering evaporation sources are arranged in the same film forming chamber is known. .

  For example, the arc evaporation source and the sputtering evaporation source are alternately switched and operated, and after performing the metal ion etching with the arc evaporation source, the arc evaporation source is stopped, the process gas is introduced, and then the hard film is formed with the sputtering evaporation source. An apparatus or method for forming a film has been proposed (see Patent Document 1).

  In addition, a film forming apparatus having a magnetic field application mechanism for an arc evaporation source and a sputtering evaporation source has been proposed (see Patent Documents 2 and 3). Note that FIG. 7 of Patent Document 3 describes, as a conventional technique, the influence of mutual interference between magnetic fields of an arc evaporation source and a sputtering evaporation source that do not have a magnetic field application mechanism.

In addition, by operating the arc evaporation source and the sputtering evaporation source at the same time, a hard film is formed, a third element is added to the film, the crystal grains of the film are refined, and wear resistance, etc. It is also known to improve. For example, by adding Si or B to a TiAlN film such as a TiN film or a cutting tool, it has been proposed that the oxidation resistance is improved and the hardness is increased by refining crystal grains (Patent Document 4, 5, see Non-Patent Document 1). In addition, a method has been proposed in which B is added to a CrN film used for a sliding member as a representative of an automobile piston ring to improve the wear resistance by increasing the hardness (see Patent Document 6). .
US Pat. No. 5,234,561 (FIG. 1, rows 9 and 10) Japanese Patent No. 2836876 (claim, FIG. 1, page 9) JP 2000-144391 A (claim, FIG. 1) Japanese Unexamined Patent Publication No. 7-310174 Japanese Patent No.2793696 JP 2000-144391 A KHKim et al. Surf. Coat. Technol. 298 (2002) 243-244, 247

  However, when the arc evaporation source and the sputtering evaporation source are operated simultaneously in the same film forming chamber, even if the arc evaporation source and the sputtering evaporation source are switched alternately, the arc evaporation source and the sputtering evaporation source are operated depending on the hard coating material and the film forming conditions. It is difficult to avoid problems in film formation, such as difficulty in forming a target hard film having a target dense hard film or a target composition, and abnormal discharge during the film formation operation. For this reason, the actual situation is that there is a limit in improving the wear resistance by increasing the hardness of the obtained hard coating.

  For example, when forming a hard nitride film such as TiN, TiCN, or TiAlN, the film is formed in a mixed gas atmosphere of Ar and nitrogen in order to form a nitride. However, in the same film forming chamber, electrons emitted from the arc evaporation source or the sputtering evaporation source are easily guided to the chamber side serving as the anode as well as the substrate. As a result, the concentration of emitted electrons is reduced, collision with the sputtering gas or reactive gas is reduced, and it is difficult to ionize the gas with high efficiency.

  An inert sputtering gas such as Ar (argon), Ne (neon), or Xe (xenon) is used as the sputtering evaporation source, while a reactive gas such as nitrogen, methane, or acetylene is used as the arc evaporation source. (Reactive gas) is used. For this reason, when arc film formation and sputtering film formation are performed simultaneously in the same film formation chamber, especially when film formation is performed with a high partial pressure of a reactive gas such as nitrogen in order to improve the film performance. Depending on the material used for the sputtering evaporation source, the sputtering target material reacts with the reaction gas to generate an insulator (insulator) on the surface of the target material, and this insulator causes abnormal discharge (arcing) at the sputtering evaporation source. ) Is likely to occur. This problem also inhibits gas ionization with high efficiency.

  When gas ionization with high efficiency is inhibited in this way, ion irradiation to the substrate cannot be strengthened, the hard coating layer cannot be densified, and the surface properties such as the surface become rough are also lowered. As a result, in the conventional film forming apparatus, particularly when the arc evaporation source and the sputtering evaporation source are operated simultaneously in the same film forming chamber, it is great for high performance and high performance such as high hardness of the hard film. Limits arise.

  The present invention has been made in view of such circumstances, and its object is to solve the problem in film formation, particularly when an arc evaporation source and a sputtering evaporation source are operated simultaneously in the same film formation chamber. An object of the present invention is to provide a composite film forming apparatus and a sputtering evaporation source that can obtain a hard film having desired characteristics without causing the above.

  In order to achieve this object, the gist of the composite film forming apparatus of the present invention is a film forming apparatus in which one or more arc evaporation sources and sputtering evaporation sources each having a magnetic field application mechanism are arranged in the same film forming chamber. Means for sequentially moving the substrate on which the film is formed between the arc evaporation source and the sputtering evaporation source so that the magnetic lines of force between the adjacent evaporation sources are connected to each other during the film formation. The magnetic field application mechanism is configured.

  In order to achieve this object, another aspect of the composite film forming apparatus of the present invention is a composition in which one or more arc evaporation sources and sputtering evaporation sources each having a magnetic field applying mechanism are arranged in the same film forming chamber. A film apparatus comprising means for sequentially moving a substrate on which a film is to be formed between the arc evaporation source and the sputtering evaporation source, and during the film formation, sputtering gas is supplied from the vicinity of the sputtering evaporation source. The reaction gas is introduced from the vicinity of the arc evaporation source.

  In order to achieve this object, the gist of the sputtering evaporation source of the present invention is a sputtering evaporation source used in the composite film forming apparatus, and uses an electrically insulating material in a portion other than the erosion area. It is that.

  Similarly, another gist of the sputtering evaporation source of the present invention is a sputtering evaporation source used in the composite film forming apparatus, and a floating potential or a ground potential is set in a portion other than the erosion area with respect to the potential of the sputtering target. This is the provision of a shield.

  In the composite film forming apparatus of the present invention, as described above, the magnetic field applying mechanism is configured so that the magnetic lines of force between the adjacent evaporation sources are connected to each other during film formation.

  For this reason, the magnetic field lines in the same film forming chamber are in a closed state (closed magnetic field structure), and as will be described in detail later, electrons emitted from the evaporation source are trapped in the closed magnetic field structure, and the substrate and Similarly, it is not easily guided into the anode chamber. As a result, even when arc film formation and sputtering film formation are performed simultaneously in the same film formation chamber, the concentration of emitted electrons increases, collision with sputtering gas and reactive gas increases, and gas ionization is performed with high efficiency. Can be implemented.

  Further, in the composite film forming apparatus of the present invention, as described in the other aspect, during the film formation, the sputtering gas is introduced from the vicinity of the sputtering evaporation source and the reaction gas is introduced from the vicinity of the arc evaporation source. For this reason, when arc film formation and sputtering film formation are performed simultaneously in the same film formation chamber, and in particular, in order to improve the film performance, film formation is performed by increasing the partial pressure of a reactive gas such as nitrogen. Even in this case, it is difficult to mix a reaction gas such as nitrogen into the sputtering gas, and the problem that abnormal discharge occurs due to the formation of an insulating film on the target surface by the ionized mixed gas is suppressed. For this reason, ionization of gas can be implemented with high efficiency.

  In the present invention, the ion irradiation of the substrate can be enhanced by promoting the ionization of the gas with high efficiency by implementing each of the above two gist or a combination thereof, and by increasing the density of the hard coating layer, High characteristics such as hardness can be achieved. In addition, the occurrence of abnormality such as abnormal discharge during film formation can be suppressed.

  Further, as in the above two aspects of the sputtering evaporation source of the present invention, by preventing voltage from being applied to the non-erosion area of the sputtering evaporation source, particles sputtered from the erosion area can be subjected to nitrogen or the like on the non-erosion area. It reacts with and bonds with the reaction gas, and is not deposited. As a result, abnormal discharge resulting from this can be prevented, and gas ionization can be performed with high efficiency.

  Hereinafter, embodiments of the composite film forming apparatus of the present invention will be specifically described with reference to the drawings. FIG. 1 is a plan view showing an embodiment of the film forming apparatus of the present invention. FIG. 2 is a plan view showing a film forming apparatus of a comparative example. FIG. 3 is a front view showing another embodiment of the composite film forming apparatus of the present invention. FIG. 4 is a plan view showing still another embodiment of the composite film forming apparatus of the present invention.

  In the film forming apparatus shown in FIGS. 1 and 2, a plurality of substrates 1 (four symmetrical in FIG. 5) are arranged on a rotating disk 9 in a chamber 8 and are circumferentially (circular). On the circumference), the sputtering evaporation sources 2 and 3 and the arc evaporation sources 5 and 6 are arranged to face each other, the sputtering evaporation sources 2 and 3 and the arc evaporation sources 5 and 6, respectively. The sputtering evaporation source and the arc evaporation source are alternately arranged so as to be adjacent to each other.

  Then, each substrate 1 is rotated by the rotation of the turntable 9 so that the substrates 1 alternately pass in front of the arc evaporation sources 5, 6 and the sputtering evaporation sources 2, 3. In this case, the arc evaporation sources 5 and 6 and the sputtering evaporation sources 2 and 3 may be rotated around the substrate 1 without rotating the turntable 9 or the substrate 1. It suffices to have means for sequentially moving the substrate on which the film is formed between the arc evaporation source and the sputtering evaporation source.

  For example, when a hard film such as TiAlN is formed using the arc evaporation sources 5 and 6, a reactive gas such as nitrogen, methane, and acetylene is introduced into the chamber 8 and has a reactivity of several Pa. Film formation is performed using a TiAl target in an atmosphere of a pressure region containing gas.

  Further, for example, in the case where a hard film such as TiAlN is formed using the sputtering evaporation sources 2 and 3, for example, the point that the TiAl target is used is the same as the film formation by arc. However, an inert gas such as Ar, Ne, or Xe used as a sputtering gas is used by mixing a reactive gas with nitrogen or the like, and the total pressure of the atmosphere is 0. The pressure is about several Pa, which is lower than that in the film formation by arc.

  Then, the rotating disk 9 is rotated to rotate each substrate 1 so that the substrates 1 alternately pass in front of the arc evaporation sources 5 and 6 and the sputtering evaporation sources 2 and 3, respectively. By sequentially performing film formation and film formation by each arc, a hard film having the same or different composition and thickness can be sequentially formed in multiple layers on the substrate 1 using the same or different hard materials. Is possible.

(Magnetic field application mechanism)
Here, in the film forming apparatus shown in FIGS. 1 and 2, both the arc evaporation sources 5 and 6 and the sputtering evaporation sources 2 and 3 have a magnetic field application mechanism 4 such as a permanent magnet provided in each of these evaporation sources. Utilizing a magnetic field 10 generated and controlled by

  However, when this magnetic field 10 is used, in the film forming apparatus of the present invention shown in FIG. 1, the magnetic fields 10 of both adjacent evaporation sources, for example, the magnetic fields 10 of the arc evaporation source 5 and the sputtering evaporation sources 2 and 3 are Connected to each other. That is, the magnetic field application mechanism 4 is configured so that the magnetic lines of force (magnetic field 10) between the adjacent evaporation sources are connected to each other during film formation.

  For this reason, the magnetic field 10 (lines of magnetic force) in the same film forming chamber 8 is in a closed state (closed magnetic field structure), and electrons emitted from the evaporation source are trapped in the closed magnetic field structure, and the substrate 1 and Similarly, it is not easily guided to the chamber 8 serving as the anode. As a result, the concentration of emitted electrons increases, collisions with sputtering gas and reactive gas increase, and gas ionization can be performed with high efficiency.

  Thereby, even when arc film formation and sputtering film formation are performed simultaneously in the same film formation chamber, the directivity of ions from both adjacent evaporation sources is improved in the film formation apparatus of the present invention shown in FIG. It is possible to increase the ion irradiation to the film and form a film with more excellent characteristics.

  On the other hand, in the comparative example film forming apparatus of FIG. 2, the magnetic fields 10 of the two adjacent evaporation sources, for example, the magnetic fields 10 of the arc evaporation source 5 and the sputtering evaporation sources 2 and 3 are not connected to each other and are independent. ing.

  Therefore, the magnetic field 10 (lines of magnetic force) in the same film forming chamber 8 is in an open state (open magnetic field structure), and the emitted electrons from the evaporation source are along the direction of each magnetic field 10 (lines of magnetic force). , Promptly (easy) and easily guided to the chamber 8. As a result, when arc film formation and sputtering film formation are performed simultaneously in the same film formation chamber, the concentration of emitted electrons is reduced, collision with sputtering gas and reactive gas is reduced, and gas ionization efficiency is lowered.

  Therefore, in the case of the comparative example film forming apparatus of FIG. 2, the directivity of ions from both evaporation sources becomes slow, the amount of ion irradiation to the substrate is reduced, and there is a high possibility of hindering the film characteristics or film forming efficiency. Become.

(Proof of ion irradiation increase effect)
The ion current flowing through the substrate 1 was measured using the film forming apparatus shown in FIGS. In the film forming apparatus of the present invention shown in FIG. 1, an ion current of about 14 mA / cm ² flowing through the substrate 1 was obtained, and the ion current flowing through the substrate 1 was clearly increased. On the other hand, in the comparative example film forming apparatus of FIG. 2, the ionic current flowing through the substrate 1 is only about 7 mA / cm ² , which is half of the ionic current, and the ionic current flowing through the substrate 1 was not increased. This result also confirms that the film forming apparatus of the present invention can increase the ion irradiation to the substrate and form a film with more excellent characteristics.

(Another embodiment of the film forming apparatus)
Next, another embodiment of the film forming apparatus of the present invention will be described with reference to FIG. In the film forming apparatus shown in FIG. 3, as shown in FIG. 1, the sputtering evaporation sources 2 and 3 and the arc evaporation sources 5 and 6 are not arranged circumferentially in the chamber 8 but alternately in series. An example of arrangement is shown. The way of arranging the evaporation sources may not necessarily be linear or curved, and the number of the evaporation sources can be freely selected.

  Also in the case of the film forming apparatus of the present invention shown in FIG. 3, the substrate 1 which is the object to be processed, or the arc evaporation sources 5 and 6 and the sputtering evaporation sources 2 and 3 are moved relative to each other by appropriate means. The arc evaporation sources 5 and 6 and the sputtering evaporation sources 2 and 3 are alternately passed in front of each other. Then, in the atmosphere containing the reactive gas in the chamber 8, the components of the hard coating layer are evaporated using the arc evaporation sources 5 and 6, and the components of the hard coating layer are evaporated using the sputtering evaporation sources 2 and 3, respectively. Then, the hard coating layer and the hard coating layer are alternately and sequentially laminated on the substrate 1 to form a target hard coating.

  Also in the film forming apparatus of the present invention shown in FIG. 3, the magnetic fields 10 of both adjacent evaporation sources, for example, the magnetic fields 10 of the arc evaporation source 5 and the sputtering evaporation sources 2 and 3 are connected to each other. That is, the magnetic field application mechanism 4 is configured so that the magnetic lines of force between the adjacent evaporation sources are connected to each other during film formation. For this reason, the magnetic field 10 in the same film forming chamber 8 is in a closed state (closed magnetic field structure), and electrons emitted from the evaporation source are trapped in the closed magnetic field structure, Is not easily guided to the chamber 8. As a result, similarly to the film forming apparatus of the present invention shown in FIG. 1, the concentration of emitted electrons is increased, the collision with the sputtering gas and the reactive gas is increased, and the gas can be ionized with high efficiency.

(Nitrogen partial pressure)
When the arc evaporation source and the sputtering evaporation source are simultaneously operated to form a hard film containing nitrogen in the film forming apparatus of the present invention as described above with reference to FIGS. 1 and 3, nitrogen is mixed into the sputtering gas. In addition, the mixed nitrogen partial pressure is preferably 0.5 Pa or more.

  As described above, the atmospheric gas conditions and the pressure conditions are greatly different between the film formation by arc and the film formation by sputtering. For this reason, in the above-mentioned Non-Patent Document 1 or the like, for example, when a hard film such as TiSiN is formed by simultaneously operating an arc evaporation source and a sputtering evaporation source, Ar and nitrogen that are used as sputtering gases, etc. The reaction gas ratio is 3: 1, the total pressure is about 0.08 Pa, the partial pressure of nitrogen is about 0.02 Pa, Ti is vaporized by an arc evaporation source, and Si is evaporated by a sputtering evaporation source to form a film. ing.

  However, when the film is formed under such conditions, since the partial pressure of nitrogen to be mixed is too low, the addition of nitrogen to the hard film becomes insufficient, and the number of macro particles in the hard film also increases. For this reason, it becomes difficult to form a dense film.

  On the other hand, in order to sufficiently add nitrogen to the hard film, suppress the generation of macro particles in the hard film, and form a film having a fine and excellent surface property, a sputtering gas is used. As described above, the nitrogen partial pressure to be mixed is preferably 0.5 Pa or more.

  The influence of this nitrogen partial pressure was investigated in the case where a hard film of TiAlCrN was formed by simultaneously operating an arc evaporation source and a sputtering evaporation source using the film forming apparatus shown in FIG. While evaporating the TiAl alloy (Ti50: Al50) with the arc evaporation source, simultaneously evaporating Cr with the sputtering evaporation source, and variously changing the ratio of nitrogen as the reaction gas and nitrogen as the reaction gas (nitrogen partial pressure) Formed. For each example, the nitrogen content (atomic%) in the hard coating, the surface roughness Ra and the Vickers hardness (Hv) of the hard coating were measured.

  The results of arranging these in relation to the nitrogen partial pressure are shown in FIGS. 5 shows the relationship between the nitrogen partial pressure and the nitrogen content in the hard coating, FIG. 6 shows the relationship between the nitrogen partial pressure and the surface roughness Ra of the hard coating, and FIG. 7 shows the relationship between the nitrogen partial pressure and the Vickers hardness of the hard coating. Each relationship is shown.

  As can be seen from FIG. 5, there is a clear difference in the nitrogen content in the hard coating, with the nitrogen partial pressure at 0.5 Pa. That is, in the region where the nitrogen partial pressure is less than 0.5 Pa, the nitrogen content in the hard coating is substantially monotonous and significantly reduced compared to the region where the nitrogen partial pressure is 0.5 Pa or more. On the other hand, in the region where the nitrogen partial pressure is 0.5 Pa or more, the nitrogen content in the hard coating is stably maintained at a high level of about 50 atomic%.

  Further, as can be seen from FIG. 6, there is a clear difference in the surface roughness Ra of the hard coating at a nitrogen partial pressure of 0.5 Pa. That is, in the region where the nitrogen partial pressure is less than 0.5 Pa, the surface roughness Ra of the hard coating is rapidly increased to about 0.38 μm. On the other hand, in the region where the nitrogen partial pressure is 0.5 Pa or more, the surface roughness Ra of the hard coating is almost stably maintained at a low level of 0.1 μm or less.

  Furthermore, as can be seen from FIG. 7, there is a clear difference in the Vickers hardness of the hard coating when the nitrogen partial pressure is 0.5 Pa. That is, in the region where the nitrogen partial pressure is less than 0.5 Pa, the Vickers hardness is significantly reduced to a level of 1100 Hv. On the other hand, in the region where the nitrogen partial pressure is 0.5 Pa or more, the Vickers hardness of the hard coating is stably maintained at a high level of about 2500 Hv.

  From these results, in order to sufficiently add nitrogen to the hard coating, suppress the generation of macro particles in the hard coating, and form a dense and excellent surface texture, mixed in the sputtering gas The significance of setting the partial pressure of nitrogen to be 0.5 Pa or higher is understood. These results and trends also apply to other hard coatings such as TiN, TiCN or TiAlN other than the investigated TiAlCrN.

(Abnormal discharge problem due to insulator formation)
However, in the above-described film formation with a nitrogen partial pressure of 0.5 Pa or more, when arc film formation and sputtering film formation are performed simultaneously in the same film formation chamber, another problem occurs depending on the material used for the sputtering evaporation source. Sometimes. That is, the sputtering target material reacts with the reaction gas to generate an insulator (insulator) on the surface of the target material, and this insulator may cause abnormal discharge (arcing) in the sputtering evaporation source. For example, when Si is used as a target material and is sputtered in nitrogen, Si easily reacts with nitrogen to form an SiN insulator on the surface of the target material, and this abnormal discharge problem is particularly likely to occur.

  Even when such an insulator is not generated, even when the sputtering target material reacts with the reaction gas to generate a compound on the surface of the target material, the evaporation rate at the sputtering evaporation source is increased by the compound layer on the surface. May be reduced. These problems also cause high efficiency and hinder gas ionization.

  Conventionally, for such a problem, sputtering is performed by keeping the partial pressure of a reactive gas such as nitrogen with respect to an inert sputtering gas low and suppressing the reaction between the reactive gas such as nitrogen and the sputtering target material. Sputtering of the target material by the gas was preferentially generated.

  In the above-mentioned Non-Patent Document 1, etc., when a hard film such as TiSiN is formed by simultaneously operating an arc evaporation source and a sputtering evaporation source, as described above, nitrogen with respect to Ar or the like serving as a sputtering gas, etc. This is why the partial pressure of the reaction gas was lowered.

  However, as described above, when the film is formed using the film forming apparatus shown in FIGS. 1 and 2, the composition of the atmosphere and the pressure region are greatly different between the arc film formation and the sputtering film formation. For this reason, in the case of forming a film by simultaneously operating an arc evaporation source that requires a relatively high pressure and a sputtering evaporation source, the reaction gas such as nitrogen with respect to the sputtering gas can be used even from the above-described film performance. It is necessary to increase the partial pressure, and the possibility of occurrence of the above-described problem increases.

(Atmospheric gas introduction method)
This problem can be addressed by introducing a sputtering gas into the chamber from the vicinity of the sputtering evaporation source and introducing a reaction gas into the chamber from the vicinity of the arc evaporation source during film formation. This embodiment is shown in FIG. The basic configuration of the film forming apparatus of the present invention in FIG. 4 is the same as that in FIG. 1 described above, but during film formation, a sputtering gas is introduced from the vicinity of the sputtering evaporation source and a reactive gas is supplied in the vicinity of the arc evaporation source. The point to introduce more is characteristic.

  More specifically, the film forming apparatus of FIG. 4 introduces sputtering gas from the vicinity of the sputtering evaporation sources 3 and 4 through the conduit 12 and the branch pipes 12a and 12b during film formation. The reaction gas is introduced from the vicinity of the arc evaporation sources 5 and 6 through the conduit 11 and the branch pipes 11a and 11b.

  Thus, in the vicinity of the sputtering evaporation sources 3 and 4, the partial pressure of the reactive gas such as nitrogen with respect to the inert sputtering gas is kept low, and the reaction between the reactive gas such as nitrogen and the sputtering target material is suppressed, Sputtering of the target material by sputtering gas can be preferentially generated.

  On the other hand, the ratio (nitrogen partial pressure) of nitrogen, which is a reactive gas to the sputtering gas in the entire atmosphere in the chamber, can be increased from the viewpoint of improving the film performance. Also, in the vicinity of the arc evaporation sources 5 and 6, the pressure of the reactive gas can be increased according to the film forming conditions by the arc.

  Even if the introduction of these atmospheric gases is used in combination with the magnetic field application mechanism shown in FIGS. 1 and 4 or alone, the inert sputtering gas is less likely to be mixed with a reactive gas such as nitrogen. The problem that abnormal discharge occurs due to the formation of an insulating film on the target surface by the ionized mixed gas is suppressed. For this reason, ionization of gas can be implemented with high efficiency.

(Abnormal discharge problem due to magnetic field formation)
Note that the abnormal discharge in the sputtering target may be caused by other causes that are not the formation of the insulator on the surface of the target material by the above-described reactive gas such as nitrogen.

  This can be said to be a problem peculiar to sputtering control by a magnetic field such as the magnetic field application mechanism 4 described above. Details of this problem will be described with reference to FIGS. 9A and 9B show the detailed structure of the sputtering evaporation sources 2 and 3, FIG. 8A is a plan view of only the target material 20 in the sputtering evaporation sources 2 and 3, and FIG. It is a front view of sputtering evaporation sources 2 and 3. 8B, 4 is a magnetic field application mechanism, 13 is a shield of the target material 20, 15 is a ground ground of the shield 13, 14 is a backing plate of the target material 20, 16 is a sputtering power source, and 17 is a target material 20. It is a jig to do.

  As shown in FIG. 8B, the magnetron sputtering evaporation sources 2 and 3 using a magnetic field form a horizontal magnetic field 10 on the surface of the target material 20, and as described above, electrons are intentionally trapped and the electron density. To promote ionization of the sputtering gas and increase the sputtering efficiency.

  In this case, an erosion area 21 and a non-erosion area 22 are inevitably generated on the surface of the target material 20 shown in FIG. In the erosion area 21 which is a hatched portion, many ions of the sputtering gas are generated, the electron density is high, and sputtering proceeds preferentially. In contrast, almost no sputtering occurs in the center portion of the target material 20 and the non-erosion area 22 at the peripheral portion of the erosion area 21. For this reason, in the non-erosion area 22, the particles sputtered from the erosion area 21 react with and react with a reactive gas such as nitrogen and are easily deposited. For this reason, this deposit may become an insulator (insulating film) on the surface of the target material, which may cause a problem of abnormal discharge.

(Sputtering evaporation source)
To solve this problem, it is preferable that no voltage is applied to the non-erosion area 22 of the sputtering evaporation source during film formation.

  As one means for this, a material that is an electrically insulating material is used for a portion of the sputtering evaporation source other than the erosion area 21 in a non-erosion area. FIGS. 9 (a) and 9 (b) show an example of this embodiment, and the basic configuration of the apparatus is the same as FIGS. 8 (a) and 8 (b). 9A and 9B, a material that is an electrically insulating material is used for the non-erosion area 23 at the center of the target material 20 and the peripheral edge of the erosion area 21, and the insulating material 23 is configured. ing. As such a material, it is preferable to use BN (boron nitride), alumina, or the like having heat resistance that can withstand the heat generated in the sputtering evaporation source.

  FIG. 10 shows an example in which a shield that is a floating potential or a ground potential is provided at a portion other than the erosion area with respect to the potential of the sputtering target as another means for preventing voltage from being applied to the non-erosion area. Is shown.

  10 (a) and 10 (b) also have the same basic configuration as the apparatus shown in FIGS. 8 (a) and 8 (b). 10A and 10B, a non-erosion area 25 at the center of the target material 20 is provided with a shield that has a floating potential. The non-erosion area 24 at the peripheral edge of the erosion area 21 is provided with a shield that is ground potential (connected to the ground earth 15).

  In the embodiment of FIGS. 9 and 10 having the above-described configuration in which no voltage is applied to the non-erosion area 22, particles sputtered from the erosion area 21 react with a reactive gas such as nitrogen on the non-erosion area 23. , It will not bond and deposit. Therefore, the problem of the abnormal discharge is prevented from occurring.

(Film composition)
Using the film forming apparatus of the present invention having the above-described configuration, the film composition and the film material and the evaporation source when forming a hard film by simultaneously operating the arc evaporation source and the sputtering evaporation source in the same chamber. The relationship will be described below.

  As the hard coating composition, for example, nitride having a cubic rock salt type structure containing any of Ti, Cr, Al, such as TiN, CrN or TiAlN, which are frequently used for cutting tools and wear-resistant sliding parts Any one of carbonitride, carbide and carbide can be applied. Other than these, any compound selected from 4A, 5A, 6A, and an element selected from one or more of Al and Si and an element selected from one or more of B, C and N can be used. All of these compounds have a cubic rock salt structure as a crystal system, and have high hardness and excellent wear resistance.

  The composite film forming apparatus of the present invention is suitable for forming a multilayer film by sequentially laminating the hard film as described above using a difference in film forming speed between an arc evaporation source and a sputtering evaporation source. The combination of the layers is a compound of an element selected from one or more of 4A, 5A, 6A and Al and Si, and an element selected from one or more of B, C and N, and It is also possible to form films having different compositions using an arc evaporation source and a sputtering evaporation source, respectively.

  And (1) a compound layer of an element selected from one or more of 4A, 5A, 6A and Al and Si and an element selected from one or more of B, C and N, (2) Si, Cu, Select a nitride, carbonitride, carbide layer of an element selected from one or more of Co, Ni, B and C, and (3) a layer selected from the metals Cu, Ni and Co, respectively, and arc It is also possible to laminate (film formation) with an evaporation source and a sputtering evaporation source.

Among the compounds of elements selected from one or more of 4A, 5A, 6A and Al and Si formed by an arc evaporation source and one or more elements selected from one or more of B, C and N, Ti, Cr, Al, Compounds containing any of V have higher hardness and are suitable as wear-resistant coatings. For this compound, the general formula is Ti (C _1-x N _x ), Cr (C _1-x N _x ), V (C _1-x N _x ), where x is 0 to 1 value, and so on]
In the binary system, TiAl (C _1-x N _x ), TiSi (C _1-x N _x ), TiCr (C _1-x N _x ), TiV (C _1-x N _x ), TiB (C _{1- x N x), CrAl (C} 1-x N x), CrSi (C 1-x N x), CrV (C 1-x N x), CrB (C 1-x N x), VAl (C 1- _{x N x), VSi (C} 1-x N x), VB (C 1-x N x) can be expressed by the like.
In the ternary system, TiAlSi (C _1-x N _x ), TiAlCr (C _1-x N _x ), TiAlV (C _1-x N _x ), TiAlB (C _1-x N _x ), TiCrSi (C _{1- x} N _x ), TiCrV (C _1-x N _x ), TiCrB (C _1-x N _x ), TiVSi (C _1-x N _x ), TiVB (C _1-x N _x ), CrAlSi (C _{1- x} N _x ), CrAlV (C _1-x N _x ), CrAlB (C _1-x N _x ), CrSiV (C _1-x N _x ), CrSiB (C _1-x N _x ), CrVB (C _{1- x N x), VAlSi (C} 1-x N x), VAlB (C 1-x N x), expressed by the like.
In the quaternary system, TiAlSiCr (C _1-x N _x ), TiAlSiV (C _1-x N _x ), TiAlSiB (C _1-x N _x ), TiAlCrV (C _1-x N _x ), TiAlCrB (C _{1 -x x} N _x ), TiAlVB (C _1-x N _x ), TiCrSiV (C _1-x N _x ), TiCrSiB (C _1-x N _x ), TiCrVB (C _1-x N _x ), CrAlSiV (C _{1- x N x), CrAlSiB (C} 1-x N x), CrAlVB (C 1-x N x), CrSiVB (C 1-x N x), VAlSiB (C 1-x N x) can be expressed by the like.

  In addition, as a compound formed by the sputtering evaporation source, among compounds of an element selected from one or more of 4A, 5A, 6A, and Al and Si, and an element selected from one or more of B, C and N, A compound of an element selected from one or more of B 1, C 2, and N 3 including W 3, Mo, and Nb is suitable. The reason why these are formed by the sputtering evaporation source is that the compounds containing the above elements are hard and excellent in oxidation resistance, but the target containing these elements generally has a high melting point and is difficult to form in the arc evaporation source. This is because of this.

These compounds include, for example, W (C _1-x N _x ) [where x is a value from 0 to 1, the same shall apply hereinafter], Mo (C _1-x N _x ), Nb (C _1-x N _x ), WSi (C _{1 -x} N _x ), MoSi (C _{1 -x} N _x ), NbSi, WAl (C _{1 -x} N _x ), NbAl (C _{1 -x} N _x ), and the like.
In addition to this, as the compound formed by the sputtering evaporation source, any one of BN, BCN, SiN, SiCN, CuN, CuCN, or metallic Cu is recommended.

  Of these compounds, compounds containing any of Ti, Cr, and Al have higher hardness. Examples of this compound include compounds such as TiN, TiCN, TiAlN, CrN, TiCrAlN, and CrAlN. In particular, a compound containing Al is excellent in oxidation resistance, and is preferable for cutting tool applications in which this oxidation resistance is particularly required. In addition, compounds containing Cr (for example, CrN, TiCrN, CrCN) are suitable for use in machine parts.

  When these hard coatings are formed in the same chamber by simultaneously operating an arc evaporation source and a sputtering evaporation source, an inert gas such as Ar as a sputtering gas and a reactive gas such as nitrogen are mixed. The film is formed by evaporating Ti with an arc evaporation source and evaporating Cr or Al with a sputtering evaporation source.

  Further, when the film is formed by simultaneously operating the arc evaporation source and the sputtering evaporation source in the same chamber, as described above, for example, the same TiAl target is used for the arc evaporation source and the sputtering evaporation source, and the respective evaporation sources are used. The film formation may be performed by controlling the composition and pressure of the nearby atmospheric gas.

(Formation of composite hard coating)
As described above, the film forming apparatus of the present invention can efficiently form a hard film by simultaneously operating an arc evaporation source and a sputtering evaporation source in the same chamber. It is particularly suitable for forming a composite hard film. The composite hard coating referred to here has a coating structure in which a hard coating layer A having a cubic rock salt structure and a hard coating layer B having a crystal structure other than the cubic rock salt structure are alternately laminated, This is a microcrystalline hard coating in which the thickness of the hard coating layer A is larger than the thickness of the hard coating layer B.

  Such a laminated composite hard coating is obtained by combining two hard coating layers having different crystal structures to form a laminated structure, whereby crystal grains of the hard coating layer A having a cubic rock salt structure as a main phase are obtained. The diameter can be easily and arbitrarily controlled finely. That is, when the hard coating layer A having a cubic rock salt type crystal structure is alternately and sequentially deposited (laminated) with the hard coating layer B having a crystal structure not having a cubic rock salt type structure, the hard coating layer B In this part, the crystal growth of the hard coating layer A as the lower layer is temporarily interrupted. Further, when the hard coating layer A is formed (laminated), crystal growth of the hard coating layer A newly starts on the hard coating layer B. Therefore, the crystal particle diameter of the hard coating layer A can be finely controlled.

  As a result, when the hard coating layer B is not provided and only the hard coating layer A is laminated, or even when the components are different, the hard coating layers A having the same cubic rock salt type crystal structure are laminated. As in the case of film formation, the crystal grain size of the hard coating layer A can be remarkably controlled as compared with the case where the crystal growth of the hard coating layer A is continued without being interrupted. By refining the crystal grains of the hard coating layer A, it is possible to obtain excellent properties that are not found in conventional hard coatings, such as increasing the hardness of the hard coating and improving wear resistance.

  As the composition of the hard coating layer A, among the hard coating compositions described above, a cubic rock salt type crystal structure is applicable.

  The composition of the hard coating layer B is selected from the group consisting of nitrides, carbonitrides, and carbides of elements selected from one or more of B, Si, Cu, Co, and Ni that do not have a cubic rock salt structure. Or selected from metal Cu, metal Co, and metal Ni. Among these, BN, BCN, SiN, SiCN, CuN, CuCN, or metal Cu is preferably exemplified.

  When these composite hard coatings are formed by using the composite film forming apparatus of the present invention and simultaneously operating an arc evaporation source and a sputtering evaporation source in the same chamber, a nitride is formed during film formation. In an atmosphere of a mixed gas of Ar and nitrogen (for example, a mixing ratio of 50:50), in the case of carbonitride, an atmosphere of a mixed gas of Ar, nitrogen and methane (for example, a mixing ratio of 50: 45: 5) Film formation is performed at a pressure of 2 to 4 Pa.

  At this time, the thicknesses of the layer A and the layer B are determined by the ratio of electric power supplied to the respective evaporation sources, and the thickness of the layer A + the layer B is determined by the rotation period of the substrate. The layer A is formed by an arc evaporation source, and the layer B is formed by a sputtering evaporation source.

  For example, when TiN is selected as layer A and SiN is selected as layer B, Ti that is a component of layer A is evaporated by arc evaporation sources 5 and 6, and Si that is a component of layer B is converted by sputtering sources 2 and 3. Evaporate. Then, when film formation is performed in the sputtering gas Ar + reactive gas nitrogen, and the apparatus shown in FIG. 1 is used, the substrate 1 is rotated so that the substrate 1 is alternately used as an arc evaporation source and a sputtering evaporation source. By passing through the front, TiN and SiN can be laminated alternately and sequentially on the substrate, and a composite hard film with a laminated structure of TiN as layer A and SiN as layer B can be easily formed. .

  The thickness of the hard coating layer A per layer is selected from the range of 2 to 200 nm. The thickness of the hard coating layer B per layer is selected from the range of 0.5 nm or more, preferably 1.0 nm or more and 1/2 or less of the thickness of the hard coating layer A per layer.

  As a laminated structure, layer A / layer B / layer A / layer B, which are alternating layers of hard coating layer A and hard coating layer B (layer A / layer B), are used as a unit. Multi-layering (multilayering) is preferred. However, as the third hard coating layer C, it has a cubic rock salt type structure, but a hard coating layer (another substance) having a different component composition is selected, and this hard coating layer C is interposed therebetween. For example, layer A / layer B / layer C or layer B / layer A / layer B / layer C may be used as one unit, and these units may be combined to perform lamination. The layer A and the layer B are used as one unit, and the number of these units can be selected from any number such as 20 to 1000.

  By applying the film forming apparatus of the present invention to the film formation of such a laminated composite hard film, each characteristic of arc evaporation and sputtering evaporation can be exhibited to the maximum. In particular, arc evaporation has a higher film formation rate than sputtering evaporation. For this reason, by forming the component of the hard coating layer A with the arc evaporation source, the layer A requiring a film thickness of about 5 times or more that of the layer B can be formed at high speed. Also, the sputtering evaporation source is easier to adjust the film deposition rate than the arc evaporation source, and operates from a very small input power (for example, 0.1 kW). Therefore, the thickness of the thin film layer such as the layer B can be accurately set. There are characteristics that can be controlled.

  In addition, by combining the characteristics of arc evaporation and sputtering evaporation, the ratio of the thickness of layer A and layer B is set within a preferable range according to the ratio of input power of the arc evaporation source and sputtering evaporation source, and then the rotation of the substrate is performed. By changing the number (rotation speed, movement speed), the repetition cycle of layer A + layer B can be arbitrarily determined. In addition, the thickness of the layer A, that is, the crystal particle diameter can be set arbitrarily and can be formed.

  As described above, according to the present invention, it is possible to provide a composite film forming apparatus and a sputtering evaporation source that can obtain a hard film having desired characteristics without causing problems in film formation. Therefore, the present invention can be applied to film formation with improved properties of wear-resistant coatings such as cutting tools and sliding members for automobiles made of cemented carbide, cermet or high-speed tool steel.

It is a top view which shows one embodiment of the film-forming apparatus of this invention. It is a top view which shows the film-forming apparatus of a comparative example. It is a front view which shows another embodiment of this invention composite film-forming apparatus. It is a top view which shows another embodiment of this invention composite film-forming apparatus. It is explanatory drawing which shows the relationship between nitrogen partial pressure and the nitrogen content in a hard film. It is explanatory drawing which shows the relationship between nitrogen partial pressure and surface roughness Ra of a hard film. It is explanatory drawing which shows the relationship between nitrogen partial pressure and the Vickers hardness of a hard film, respectively. FIG. 8A is a plan view of a sputtering target material, and FIG. 8B is a front view of the sputtering evaporation source. FIG. 9 (a) is a plan view of a sputtering target material, and FIG. 9 (b) is a front view of the sputtering evaporation source. FIG. 10 (a) is a plan view of a sputtering target material, and FIG. 10 (b) is a front view of the sputtering evaporation source.

Explanation of symbols

1: substrate, 2, 3: sputtering evaporation source, 4: magnetic field application mechanism,
5, 6: Electron beam evaporation source, 8: chamber, 9: rotating disk, 10: magnetic field,
11, 12: Conduit, 13: Shield, 14: Backing plate, 15: Ground earth, 16: Sputtering power supply, 17: Jig, 20: Target material, 21: Erosion area,
22, 24, 25: Non-erosion area

Claims (8)

  A film forming apparatus in which one or more arc evaporation sources and sputtering evaporation sources each having a magnetic field application mechanism are arranged in the same film forming chamber, wherein a substrate on which a film is formed is connected to the arc evaporation source and the sputtering evaporation source. A composite film forming apparatus, characterized in that the magnetic field applying mechanism is configured so that the magnetic field lines of the adjacent evaporation sources are connected to each other during film formation. .   A film forming apparatus in which one or more arc evaporation sources and sputtering evaporation sources each having a magnetic field application mechanism are arranged in the same film forming chamber, wherein a substrate on which a film is formed is connected to the arc evaporation source and the sputtering evaporation source. And a means for relatively moving them between them. During the film formation, a sputtering gas is introduced from the vicinity of the sputtering evaporation source, and a reactive gas is introduced from the vicinity of the arc evaporation source. Membrane device.   A film forming apparatus in which one or more arc evaporation sources and sputtering evaporation sources each having a magnetic field application mechanism are arranged in the same film forming chamber, wherein a substrate on which a film is formed is connected to the arc evaporation source and the sputtering evaporation source. The magnetic field applying mechanism is configured so that the magnetic lines of force between adjacent evaporation sources are connected to each other during film formation, and a sputtering gas is formed during film formation. Is introduced from the vicinity of the sputtering evaporation source, and the reactive gas is introduced from the vicinity of the arc evaporation source.   When the arc evaporation source and the sputtering evaporation source are simultaneously operated to form a hard film containing nitrogen, nitrogen is mixed in the sputtering gas, and the partial pressure of the mixed nitrogen is 0.5 Pa or more. Item 4. The composite film forming apparatus according to any one of Items 1 to 3.   The composite film-forming apparatus of any one of Claims 1 thru | or 4 which used the material which is an electrically insulating material for parts other than an erosion area as said sputtering evaporation source.   The composite film-forming apparatus of any one of Claims 1 thru | or 4 which provided the shield which becomes a floating electric potential or a ground electric potential with respect to the electric potential of a sputtering target in parts other than an erosion area as said sputtering evaporation source.   6. A sputtering evaporation source used in the composite film forming apparatus according to claim 5, wherein a material that is an electrically insulating material is used in a portion other than the erosion area. The sputtering evaporation source used in the composite film forming apparatus according to claim 6, wherein a shield other than the erosion area is provided with a shield having a floating potential or a ground potential with respect to the potential of the sputtering target.

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