JP2015093997A - Film deposition apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film deposition apparatus capable of stably applying a high bias voltage to a work stored in a process chamber.SOLUTION: There is provided a film deposition apparatus that applies a bias voltage to a work to be processed such that plasma is transported to its surface. The film deposition apparatus includes: a process chamber; a stage holder for housing which is stored in the process chamber; an insulation stage which is arranged on a surface of the stage holder and made of an insulating material; a work holder which is mounted with a work, arranged on the stage holder through the insulation stage, and stored in the process chamber; an insulation pipe which is arranged in the stage holder at least partially, and has one end part penetrating a wall surface of the stage holder and the insulation stage so that an opening end of the end part faces the work holder, and is made of an insulating material; and a bias introduction shaft which is arranged in the insulation pipe, and applies the bias voltage to the work through the work holder.

Description

  The present invention relates to a film forming apparatus that applies a bias voltage to a workpiece being processed in a process chamber.

  A film forming apparatus using plasma transported on a workpiece to be processed is used. For example, according to a vacuum arc deposition apparatus using a method called a filtered arc deposition (FAD) method or a filtered cathodic vacuum arc (FCVA) method, an arc is formed on the target surface (cathode) of the material. A thin film is formed on the work by continuously generating a discharge and guiding the ionized material to the work surface.

  In a film forming apparatus using plasma, a method of drawing a plasma transported on a workpiece onto the workpiece surface by applying a bias voltage to the workpiece can be employed. For example, in a vacuum arc deposition apparatus, an ion mixing method has been proposed in which ions are injected into a work with high energy in order to improve film adhesion (see, for example, Patent Document 1). This improves the adhesion of the film.

Japanese Patent No. 3555928

  However, the higher the bias voltage, the more difficult it is to apply the bias voltage to the workpiece while ensuring the insulation between the portion where the bias voltage propagates and the portion of the ground potential. When insulation cannot be ensured, there arises a problem that a desired bias voltage cannot be applied to the workpiece due to leakage current flowing between the portion where the bias voltage propagates and the portion of the ground potential. In addition, abnormal discharge may occur between the portion where the bias voltage propagates and the portion of the ground potential, and the workpiece, parts in the process chamber, or the like may be damaged.

  In view of the above problems, an object of the present invention is to provide a film forming apparatus capable of stably applying a high bias voltage to a work housed in a process chamber.

  According to one aspect of the present invention, there is provided a film forming apparatus for applying a bias voltage to a workpiece to be processed whose plasma is transported to a surface, wherein the film forming device is stored in (a) a process chamber and (b) a process chamber. (C) an insulating stage made of an insulating material disposed on the surface of the stage holder, and (d) a work is mounted and placed on the stage holder via the insulating stage and placed in the process chamber. The stored work holder and (e) at least part of the work holder is disposed in the stage holder, one end penetrates the wall surface of the stage holder and the insulating stage, and the open end of the end faces the work holder. A tubular insulating pipe made of a material, and (f) a bias introduction shaft that is arranged inside the insulating pipe and applies a bias voltage to the work through the work holder. Film forming apparatus is provided with and.

  ADVANTAGE OF THE INVENTION According to this invention, the film-forming apparatus which can apply a high bias voltage stably to the workpiece | work stored in the process chamber can be provided.

  The surface of the insulating pipe and the insulating stage is uneven along the creeping distance from the end of the insulating material covering the portion where the bias voltage propagates to the portion set to the ground potential along the surface of the insulating material. Form. Thereby, while suppressing an increase in the size of the process chamber and the stage holder, it is possible to ensure the insulation between the portion where the bias voltage propagates and the portion of the ground potential by increasing the creepage distance.

  Furthermore, the work holder can be attached to or detached from the insulating stage before and after the processing by further providing a work attaching / detaching mechanism for attaching / detaching the work holder to / from the stage holder. Also, a work rotation mechanism that exposes the end of the insulation pipe to the outside of the stage holder via a rotation introducer arranged in the stage holder, and rotates the work in the process chamber with the insulation pipe and the bias introduction shaft as a rotation axis. Thus, the film can be uniformly formed on the main surface of the workpiece. At this time, a bias voltage can be propagated to the bias introduction shaft by disposing a rotary connector at the other end of the insulating pipe.

  Further, by providing an inclination mechanism for inclining the stage holder in the process chamber, it is possible to prevent only a specific region of the main surface from being directed in the plasma supply direction when the main surface of the workpiece is a curved surface.

It is a schematic diagram which shows the example of the film-forming apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the structure of the film-forming apparatus which concerns on embodiment of this invention. 3A and 3B are schematic views showing the structure of an insulation shield and a bias introduction shaft of a film forming apparatus according to an embodiment of the present invention. FIG. 3A is a cross-sectional view along the extending direction, and FIG. It is sectional drawing along the III-III direction of (a). FIG. 4A is a schematic diagram illustrating a work detachment mechanism of a film forming apparatus according to an embodiment of the present invention, and FIG. 4A illustrates a state in which a work holder on which a work is mounted is closely attached to and held on an insulating stage on a stage holder; FIG. 4B shows a state where the work holder on which the work is mounted is separated from the stage holder. It is a schematic diagram which shows the workpiece | work rotation mechanism of the film-forming apparatus which concerns on embodiment of this invention. It is a schematic diagram explaining the function of the inclination mechanism of the film-forming apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the example of the workpiece | work processed by the film-forming apparatus which concerns on embodiment of this invention, FIG.7 (a) shows the example which has a convex curved surface, FIG.7 (b) shows a concave curved surface. The example which has is shown. It is a schematic diagram which shows the example of arrangement | positioning of each mechanism of the film-forming apparatus which concerns on embodiment of this invention. 6 is a schematic diagram illustrating an example of a film forming apparatus of Comparative Example 1. FIG. 10 is a schematic diagram illustrating an example of a film forming apparatus of Comparative Example 2. FIG. 10 is a schematic diagram illustrating an example of a film forming apparatus of Comparative Example 3. FIG. It is a schematic diagram which shows the example of the spatial distance in the film-forming apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the example of the creeping distance in the film-forming apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the other example of the creeping distance in the film-forming apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the example which lengthens a creeping distance in the film-forming apparatus which concerns on embodiment of this invention.

  Embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic. Further, the embodiment described below exemplifies an apparatus and a method for embodying the technical idea of the present invention, and the embodiment of the present invention has the following structure and arrangement of components. It is not something specific. The embodiment of the present invention can be variously modified within the scope of the claims.

  A film forming apparatus 1 according to an embodiment of the present invention is shown in FIG. FIG. 1 shows an arc plasma film forming apparatus employing a FAD method in which a desired thin film is formed on a workpiece 100 to be processed using a plasma 300 generated by arc discharge. First, the arc plasma film forming apparatus will be described.

  The arc plasma film forming apparatus shown in FIG. 1 generates a plasma 300 containing positive ions of raw materials contained in the target 200 by arc discharge generated in the discharge chamber 420 using the film forming target 200 as a cathode. Generate. The target 200 is stored in the storage chamber 410 and a part thereof is exposed in the discharge chamber 420. The positive ions of the target 200 included in the plasma 300 are transported from the discharge chamber 420 to the surface of the work 100 in the process chamber 10 via the plasma transport path 430, and a thin film is formed on the work 100.

  The plasma 300 is induced along the plasma transport path 430 by a magnetic field formed by the multistage induction coils 441 to 446 arranged along the plasma transport path 430. Hereinafter, the induction coil 441 to the induction coil 446 are collectively referred to as “induction coil 440”. The induction coil 440 is, for example, an annular electromagnetic induction coil that is excited by a supplied current. The strength of the magnetic field formed by the induction coil 440 is controlled according to the magnitude of the current supplied by the excitation current source (not shown). The central magnetic field is controlled by controlling the current flowing through the induction coil 440, and the plasma 300 is induced in the plasma transport path 430. As shown in FIG. 1, the discharge chamber 420, the plasma transport path 430, and the induction coil 440 are collectively referred to as “gun source unit 400” below.

  In the arc plasma film forming apparatus shown in FIG. 1, the plasma 300 transported from the gun source unit 400 onto the work 100 in the process chamber 10 by applying a bias voltage to the work 100 is indicated by an arrow A1. To the surface of the workpiece 100. The process chamber 10 will be described below with reference to FIG.

  The process chamber 10 stores a stage holder 20 on which a work holder 21 on which a work 100 is mounted is disposed. The stage holder 20 is a casing having a hollow inside. During processing of the workpiece 100 by the film forming apparatus 1, the inside of the process chamber 10 is in a vacuum state, but the inside of the stage holder 20 is maintained at atmospheric pressure. Note that the inside of the process chamber 10 is evacuated by a vacuum pump 11 to maintain a vacuum state.

  The workpiece 100 is fixed to the workpiece holder 21, and the workpiece 100 is held by the stage holder 20 together with the workpiece holder 21. An insulating stage 22 made of an insulating material is disposed on the work holder mounting surface of the stage holder 20, and the work holder 21 is held by the stage holder 20 with the insulating stage 22 interposed therebetween.

  Inside the stage holder 20, a tubular insulating pipe 30 made of an insulating material is disposed through the wall surface on which the work holder 21 of the stage holder 20 is disposed. That is, one end 31 of the insulating pipe 30 is exposed outside the stage holder 20. At this time, a through hole is formed in the stage holder 20 and the insulating stage 22 so that the open end of the end portion 31 faces the work holder 21. For example, an alumina material or the like is used for the insulating pipe 30 and the insulating stage 22.

  Further, a bias introduction shaft 40 is disposed inside the insulating pipe 30. The bias introduction shaft 40 is electrically connected to the work holder 21 at the opening end of the end portion 31 of the insulating pipe 30, and applies a bias voltage to the work 100 fixed to the work holder 21. For the bias introduction shaft 40 and the work holder 21, a conductor such as stainless steel (SUS), copper (Cu), or aluminum (Al) is used.

  The work holder 21 is fixed to the end of the bias introduction shaft 40 by, for example, a pin or a hook.

  The insulating pipe 30 and the bias introduction shaft 40 may be in close contact with each other, or a gap may be provided between the insulating pipe 30 and the bias introduction shaft 40. When there is a gap between the insulating pipe 30 and the bias introduction shaft 40, for example, as shown in FIGS. 3A and 3B, an O-ring seal 35 is arranged to provide the insulation pipe 30 and the bias introduction shaft 40. Perform a vacuum seal in between.

  As shown in FIGS. 4A and 4B, the film forming apparatus 1 includes a work detaching mechanism 70 that detaches the work holder 21 from an insulating stage 22 provided on the stage holder 20. That is, the insulating pipe 30 and the bias introduction shaft 40 in the interior of the insulation pipe 30 and the bias introduction shaft 40 connected to the insulation pipe 30 and the bias introduction shaft 40 formed in the insulation pipe 30 through the pipe support portion 75 of the insulation pipe 30 are indicated by an arrow A3. Move as shown. As a result, the work holder 21 is separated from or in close contact with the insulating stage 22. By separating the work holder 21 from the insulating stage 22, the work holder 21 can be attached to or detached from the insulating stage 22 before and after processing.

  For example, an air cylinder or the like can be employed as the work detaching mechanism 70. FIG. 4 shows an example in which the workpiece attaching / detaching mechanism 70 is disposed on both sides of the insulating pipe 30. However, if the insulating pipe 30 and the bias introduction shaft 40 can move stably, even if the workpiece attaching / detaching mechanism 70 is one unit. Good.

  Further, as shown in FIG. 5, the film forming apparatus 1 includes a work rotation mechanism 80 that rotates the work 100 fixed to the work holder 21 around the insulating pipe 30 and the bias introduction shaft 40 in the process chamber 10. . For example, by rotation of the work rotation mechanism 80 indicated by an arrow A4 in FIG. 5, the extending direction of the insulating pipe 30 and the bias introduction shaft 40 is rotated in the direction of the arrow A5 via the gear 85 connected to the insulating pipe 30. . For the work rotating mechanism 80, for example, a motor or the like is employed.

  In order to rotate the work 100 and the work holder 21 arranged outside the stage holder 20 by the rotation of the insulating pipe 30 and the bias introduction shaft 40 arranged in the stage holder 20, the rotation introducer 50 is rotated by the stage holder 20. Is placed inside. The rotation introducer 50 is, for example, a magnetic fluid seal, and the ends of the insulating pipe 30 and the bias introduction shaft 40 are exposed to the outside (in vacuum) of the stage holder 20 via the rotation introducer 50. By connecting the bias introduction shaft 40 to the work holder 21 outside the stage holder 20, the work 100 can be rotated in a vacuum.

  By rotating the main surface of the workpiece 100 facing the plasma supply direction from the gun source unit 400 with the surface normal direction of the main surface as the rotation axis direction as described above, the film is uniformly formed on the main surface of the workpiece 100. Can be processed.

  In the film forming apparatus 1 shown in FIG. 2, a bias voltage is supplied from the bias supply apparatus 12 into the process chamber 10. The bias supply device 12 outputs a DC voltage or a DC pulse voltage, for example. The bias voltage output from the bias supply device 12 passes through the inside of the support portion 13 that supports the stage holder 20 in the process chamber 10, and propagates through the bias cable 16 disposed in the stage holder 20. The bias cable 16 is covered with an insulating material, and is further wired in the air away from the wall surface of the process chamber 10 and the wall surface of the stage holder 20.

  As shown in FIG. 2, the bias cable 16 is supported by the insulating support portion 14 inside the hollow support portion 13, and the bias cable 16 is disposed so as to be separated from the inner wall of the support portion 13. . The bias cable 16 has a structure in which a conductor is covered with an insulating material, and an insulating support portion 14 is formed on the outside thereof.

  In order to rotate the work holder 21 together with the insulating pipe 30 and the bias introduction shaft 40 as described above, the bias introduction shaft 40 and the bias cable 16 are preferably electrically connected using, for example, the rotary connector 60 or the like. In other words, the rotary connector 60 is disposed at the end 32 of the insulating pipe 30 opposite to the end 31 on the workpiece 100 side. The rotary connector 60 electrically connected to the bias introduction shaft 40 and the bias cable 16 are electrically connected. The rotary connector 60 is covered with an insulating material 65.

  The film forming apparatus 1 further includes an inclination mechanism 15 that inclines the stage holder 20 in the process chamber 10. The tilt mechanism 15 rotates the support portion 13 that supports the stage holder 20 with the extending direction of the support portion 13 as the rotation axis direction as indicated by an arrow A2 in FIG. As a result, the stage holder 20 is tilted as indicated by an arrow A6 in FIG. 6, and the direction of the main surface of the workpiece 100 mounted on the stage holder 20 changes. FIG. 6 is a view seen from the extending direction of the support portion 13.

  The tilt mechanism 15 is, for example, a case where the main surface 101 to be processed of the workpiece 100 has a convex curved surface as shown in FIG. 7A, or a concave curved surface as shown in FIG. 7B. This is effective. That is, when the main surface 101 of the workpiece 100 is a curved surface, it is possible to prevent only a specific region of the main surface 101 from being directed to the plasma supply direction from the gun source unit 400. Thereby, even if the main surface 101 of the workpiece 100 is a curved surface, the entire main surface can be processed uniformly.

  For example, as shown in FIG. 8, the workpiece attaching / detaching mechanism 70 and the workpiece rotating mechanism 80 are arranged around the rotation introducer 50 in the stage holder 20. FIG. 8 is a plan view of the insulating pipe 30 and the bias introduction shaft 40 as viewed from the extending direction. Although FIG. 8 shows an example in which the cross section of the insulating pipe 30, the bias introduction shaft 40, and the stage holder 20 is circular, the cross section may be other shapes such as a polygon.

  Since the inside of the stage holder 20 is at atmospheric pressure, the workpiece attaching / detaching mechanism 70, the workpiece rotating mechanism 80 and the like do not need to be vacuumed. For this reason, the manufacturing cost of the film-forming apparatus 1 can be suppressed.

  Next, securing insulation in the film forming apparatus 1 will be described. Hereinafter, a portion included in a path through which the bias voltage applied to the workpiece 100 propagates is referred to as a “bias application unit”. That is, the bias introduction shaft 40, the rotary connector 60, the work holder 21, the work 100, and the like are bias application units. In addition, a portion that is set to the ground potential during the processing process of the workpiece 100 is hereinafter referred to as a “ground potential portion”. For example, the wall surface of the process chamber 10, the stage holder 20, the support portion 13, and the like are ground potential portions.

  If insulation is not maintained between the bias application unit and the ground potential unit, a leak current flows between the bias application unit and the ground potential unit, and a bias voltage having a desired magnitude cannot be applied to the workpiece 100. Problems arise. In addition, abnormal discharge may occur between the bias application unit and the ground potential unit, and the workpiece 100 and the components in the process chamber 10 may be damaged.

  For this reason, the bias introduction shaft 40 which is a bias application part is shielded by the insulating pipe 30. The material and thickness of the insulating pipe 30 are selected in consideration of the magnitude of the bias voltage and the dielectric breakdown voltage of the material so that the bias introduction shaft 40 can be shielded even when the bias voltage is high. For example, the insulating pipe 30 is made of an alumina material having a thickness of about 10 cm.

  The work holder 21 and the stage holder 20 are shielded by an insulating stage 22. Also for the insulation stage 22, the material and thickness of the insulation stage 22 are selected in consideration of the magnitude of the bias voltage and the dielectric breakdown voltage of the material. For example, the insulating stage 22 is made of an alumina material having a thickness of about 20 cm. Further, the rotary connector 60 is shielded with an insulating material 65 having a sufficient thickness.

When the insulating pipe 30, the insulating stage 22, and the insulating material 65 are made of alumina having a dielectric breakdown voltage of 13.0 kV / mm, for example, the following expression (1) is established as the bias voltage V (kV). Set the film thickness d (mm) of alumina to:

d ≧ V / 13.0 × k (1)

In equation (1), k is a safety factor. In order to make the insulating material 65 covering the rotary connector 60 sufficiently thick, for example, k = 10.

  In addition, it is necessary to maintain insulation between a portion exposed without being covered with the insulating material of the bias applying portion and the ground potential portion.

  According to the process chamber 10 according to the embodiment of the present invention, it is possible to apply a bias voltage higher than that of the prior art to the workpiece and to suppress an increase in the size of the apparatus. This will be explained by comparison with.

  Comparative Examples 1 to 3 shown in FIGS. 9 to 11 will be discussed below. Comparative Examples 1 to 3 are examples of plasma chambers that can be used in a vacuum arc deposition apparatus using the FAD method.

  In the comparative example 1 shown in FIG. 9, the rotary introducer 502 is used to introduce the rotary shaft 501 connected to the work holder 21a to which the work 100 is fixed into the process chamber 10a maintained in a vacuum. Then, a bias voltage is supplied from the bias supply device 503 to the rotation introducer 502, and the bias voltage is applied to the workpiece holder 21 a and the workpiece 100 via the rotation shaft 501 disposed inside the rotation introduction device 502.

  In Comparative Example 2 shown in FIG. 10, a bias voltage is applied to the workpiece 100 via a slip ring 504 such as a carbon brush installed at the end of the rotating shaft 501 in the stage holder 20a.

  In Comparative Example 1 and Comparative Example 2, the process chamber 10a and the stage holder 20a are ground potential parts, and the work holder 21a and the rotation introducer 502 are bias application parts. 9 to 11, the bias application unit is indicated by a bold line. In order to ensure insulation between the bias application unit and the process chamber 10a and the stage holder 20a, an insulating material 505 is disposed between the rotation introducer 502 and the process chamber 10a.

  When a bias voltage of about −10 kV to −50 kV is applied to the workpiece 100 via the magnetic fluid seal rotation introducer 502 as in Comparative Example 1, heat generation and deterioration of the bearing of the rotating unit and the magnetic flow of the vacuum seal unit occur. Damaged parts. For this reason, in the configuration of Comparative Example 1, a high bias voltage cannot be applied to the workpiece 100.

  Further, when a high bias voltage is applied to the workpiece 100 via the slip ring 504 as in the comparative example 2, it is necessary to use a large size slip ring 504 for high voltage.

  Furthermore, in Comparative Example 1 and Comparative Example 2, in order to ensure the insulation between the bias application unit and the ground potential unit, it is sufficient between the bias application unit such as the rotation introducer 502 and the work holder 21a and the ground potential unit. It is necessary to secure a large clearance and creepage distance. For example, it is necessary to increase the distance between the rotation introducer 502 and the stage holder 20a and the distance between the slip ring 504 and the wall surface of the stage holder 20a. For this reason, the problem that the size of the process chamber 10a or the stage holder 20a becomes large arises.

  In the comparative example 3 shown in FIG. 11, in order to rotate the workpiece | work 100, the rotating shaft 601 is penetrated inside the process chamber 10b. The rotating shaft 601 is rotated by an external motor 605. By supplying a bias voltage to the rotary shaft 601 from the bias supply device 604, the bias voltage is applied to the workpiece 100 on the workpiece holder 21b via the bearing 602 and the gear 603.

  When a high bias voltage is applied to the workpiece 100 in the configuration of the comparative example 3, a high bias voltage is applied to the rotating shaft 601, the bearing 602, the gear 603, and the workpiece holder 21b arranged in a vacuum. For this reason, the insulating material 606 is disposed at the introduction portion of the rotating shaft 601 into the process chamber 10b, and the insulating material 607 is disposed at a portion where the bearing 602 is supported by the process chamber 10b. An insulator 608 is disposed between the motor 605 and the rotating shaft 601. It is necessary to ensure a sufficient spatial distance and creepage distance between the bias applying unit and the inner wall surface of the process chamber 10b which is the ground potential unit. As a result, there arises a problem that the size of the process chamber 10b increases.

  In the process chamber 10 according to the embodiment of the present invention, the following countermeasures are taken for the problem of the comparative example described above with respect to the spatial distance and creepage distance between the bias application unit and the ground potential unit. The following measures can be set based on new knowledge obtained by the present inventors through repeated experiments.

First, with the bias voltage set to V, the condition of equation (2) is set for the spatial distance Y1 between the bias applying unit and the ground potential unit:

Y1 (mm) ≧ | V (kV) | × 3 (2)

The spatial distance Y1 is a distance between the bias application unit and the ground potential unit that directly faces the bias application unit.

  For example, the distance D1 between the workpiece 100 and the inner wall surface of the process chamber 10 shown in FIG. 12 is an example of the spatial distance Y1. When a bias voltage of −25 kV is applied to the workpiece 100, the distance D1 is set to 75 mm or more.

For the creepage distance Y2 between the bias applying part and the ground potential part, the condition of the formula (3) is set:

Y2 (mm) ≧ | V (kV) | × 6 (3)

The creepage distance is, for example, a distance from the end portion of the insulating material covering the bias application portion to the ground potential portion along the surface of the insulating material. An example of the creepage distance is shown in FIG.

  As shown in FIG. 13, a distance D <b> 2 along the surface of the insulating pipe 30 from the bias introduction shaft 40 to the pipe support 75 at the end 32 of the insulating pipe 30 is an example of a creeping distance. A distance D3 along the surface of the insulating pipe 30 from the bias introducing shaft 40 to the rotation introducing device 50 at the end 31 of the insulating pipe 30 is also a creeping distance.

  Furthermore, as shown in FIG. 14, the distance D4 along the surface of the insulating stage 22 and the surface of the insulating pipe 30 from the work holder 21 to the stage holder 20 is also a creepage distance.

  The distance D2 to the distance D4 are set so as to satisfy the expression (3). For example, the distance D2 to the distance D4 are set to 150 mm or more when the bias voltage is −25 kV, and 300 mm or more when the bias voltage is −50 kV.

  In order to increase the distance D2 while suppressing an increase in the size of the process chamber 10 or the stage holder 20, unevenness may be formed on the outer surface of the insulating pipe 30, for example, as shown in FIG. That is, the outside of the insulating pipe 30 is formed into a fin shape.

  In order to increase the distance D4, it is effective to make the insulating stage 22 thick. Alternatively, irregularities may be formed on the surface of the insulating stage 22.

  The length of the bias introduction shaft 40 can be shortened as the height difference of the unevenness formed on the outer surface of the insulating pipe 30 is larger. Moreover, the distance from the work holder 21 to the stage holder 20 can be shortened as the height difference of the unevenness formed on the surface of the insulating stage 22 is larger. For example, the distance from the end portion 32 of the insulating pipe 30 to the pipe support portion 75 is set to about 100 mm when unevenness is formed on the outer surface of the insulating pipe 30, and is set to 200 mm or more when there is no unevenness. The film forming apparatus 1 can be downsized as the height difference of the unevenness increases.

  As described above, in the film forming apparatus 1 according to the embodiment of the present invention, the bias introduction shaft 40 that propagates the bias voltage applied to the workpiece 100 is shielded by the insulating pipe 30. For this reason, it is possible to stably apply a high bias voltage to the workpiece 100 while ensuring insulation between the bias application unit and the ground potential unit while suppressing an increase in the size of the film forming apparatus 1. Furthermore, by defining the spatial distance Y1 and the creepage distance Y2 as shown in the equations (2) and (3), the insulation between the bias applying portion and the ground potential portion can be reliably maintained. When the apparatus size is the same, the bias voltage that can be stably applied to the work 100 is about −500 V in the conventional structure, whereas the film forming apparatus 1 can stably apply a bias voltage of about −30 kV to the work 100. Can be applied.

  For example, according to the arc plasma film forming apparatus shown in FIG. 1, a film having high adhesion can be formed on the workpiece 100 by applying a high bias voltage of about −30 kV to the workpiece 100. By using a carbon target for the target 200, a diamond-like carbon (DLC) film or the like can be favorably formed on the workpiece 100.

  The workpiece 100 is, for example, a lens mold or a substrate. According to the film forming apparatus 1 that can apply a high bias voltage of about −30 kV to the workpiece 100 and further includes the workpiece rotating mechanism 80 that rotates the workpiece 100 and the tilting mechanism 15 that tilts the workpiece 100, the surface has a curved surface. A desired film can be satisfactorily formed on the mold. For example, a carbon film is formed on the surface of a lens mold as a heat resistant protective film.

  Moreover, since abnormal discharge in the process chamber 10 is suppressed, damage to the workpiece 100 to be processed and shortening of the product life are prevented. The surface roughness is reduced, and it is possible to reduce the friction coefficient and improve the friction resistance when a tool or a machine part is a processing target.

(Other embodiments)
As mentioned above, although this invention was described by embodiment, it should not be understood that the description and drawing which form a part of this indication limit this invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  For example, the configuration of the process chamber 10 according to the embodiment of the present invention can be applied to a plasma chemical vapor deposition (CVD) apparatus other than the arc plasma film forming apparatus, a plasma sputtering apparatus, a plasma ashing apparatus, a plasma etching apparatus, and the like. is there. Even in these apparatuses, plasma can be effectively drawn into the surface of the workpiece 100.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1 ... Film-forming apparatus 10 ... Process chamber 13 ... Support part 15 ... Inclination mechanism 16 ... Biasing cable 20 ... Stage holder 21 ... Work holder 22 ... Insulating stage 30 ... Insulating pipe 31, 32 ... End part 40 ... Bias introduction shaft 50 DESCRIPTION OF SYMBOLS ... Rotation introducer 60 ... Rotary connector 70 ... Work removal mechanism 80 ... Work rotation mechanism 100 ... Work 200 ... Target 300 ... Plasma 400 ... Gun source part 410 ... Storage chamber 420 ... Discharge chamber 430 ... Plasma transport path 440 ... Induction coil

Claims (8)

A film forming apparatus for applying a bias voltage to a workpiece to be processed whose plasma is transported to the surface,
A process chamber;
A stage holder of a housing stored in the process chamber;
An insulating stage made of an insulating material disposed on the surface of the stage holder;
The work holder on which the work is mounted and disposed on the stage holder via the insulating stage and stored in the process chamber;
A tube shape made of an insulating material, at least a part of which is arranged in the stage holder, one end of which penetrates the wall surface of the stage holder and the insulating stage, and the open end of the end faces the work holder. Insulated pipes,
A film forming apparatus comprising: a bias introduction shaft that is disposed inside the insulating pipe and applies the bias voltage to the work through the work holder. The spatial distance between the portion where the bias voltage propagates and the portion set at the ground potential directly opposite to the portion is equal to or greater than | V | × 3 (mm), where the bias voltage is V (kV). ,
The creepage distance from the end of the insulating material covering the portion where the bias voltage propagates to the portion set to the ground potential along the surface of the insulating material is represented by | V, where the bias voltage is V (kV). The film forming apparatus according to claim 1, wherein | × 6 (mm) or more.   The film forming apparatus according to claim 2, wherein unevenness is formed along the creepage distance on the surfaces of the insulating pipe and the insulating stage.   The film forming apparatus according to claim 1, further comprising a work detaching mechanism that detaches the work holder from the stage holder. A work rotation mechanism for rotating the work in the process chamber with the insulating pipe and the bias introduction shaft as a rotation axis;
And a rotation introducer disposed in the stage holder, wherein the end of the insulating pipe is exposed to the outside of the stage holder through the rotation introducer. 5. The film forming apparatus according to any one of 4 above.   The film forming apparatus according to claim 5, further comprising a rotary connector disposed at the other end of the insulating pipe and propagating the bias voltage to the bias introduction shaft.   The film forming apparatus according to claim 1, further comprising an inclination mechanism for inclining the stage holder in the process chamber. A discharge chamber in which the target is stored;
A plasma transport path connecting the process chamber and the discharge chamber; and arc plasma formed on the surface of the target by exciting an arc discharge in the discharge chamber on the workpiece via the plasma transport path. The film forming apparatus according to claim 1, wherein a film that is transported and mainly includes a raw material contained in the target is formed on the workpiece.

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