JP2003277937A - Electrode member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode member capable of preventing any mixture of a film deposited on an electrode surface in a thin film under film deposition as an exfoliation film, or any defective film deposition attributable to minor abnormal discharge generated from the exfoliation film. <P>SOLUTION: A diamond-like carbon protective film of homogeneous film quality is deposited on a magnetic base material 7 having a ferromagnetic thin film fed from a feeding roller 9 by optimizing the area ratio of the electrode member 18 to an aperture 19, and a magnetic medium capable of suppressing the drop-out number and improving the durability is manufactured. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode member having a conductive plate member housed in an enclosure having an opening, and more particularly to injecting a charge into a deposition material such as plasma polymerization or plasma chemical vapor deposition. The present invention relates to an electrode member suitable for the vapor deposition method.

[0002]

2. Description of the Related Art Recent products using thin films have been extensively researched and developed, beginning with semiconductors and expanding to information recording devices such as thermal recording heads, information recording media such as magnetic recording media and phase change recording media. Has been done in. Among them, attention has been paid to the formation of a functional thin film material as an interlayer insulating film or a protective film, and the performance of the interlayer insulating film or the protective film is one of the important basic techniques for determining the reliability of the product. On the other hand, for industrially stable supply, lengthening and high-speed stable film formation are essential. A plasma polymerization method and a plasma chemical vapor deposition (plasma CVD) method, which have a high film formation rate, are advantageous for this high-speed stabilized film formation, and various proposals have been made.

[0003]

However, in the method proposed hitherto, when the supply of the film-forming raw material is increased to form the film over a long length in order to improve the film-forming rate, the film is also formed on the surface of the plasma discharge electrode. The film formed on the surface of the electrode peels off (hereinafter referred to as the peeling film) and is mixed into the film being formed, and the fragments of the peeling film induce a minute abnormal discharge inside the discharge tube. However, there is a problem that a film formation defect occurs. This problem is, for example, an increase in dropout when applied to a protective film of a magnetic recording medium or a phase change recording medium,
Oxidation deterioration etc. occurs due to deterioration of durability or contact of the material of the recording layer with the outside air, for example, when used as an interlayer insulating film of semiconductor etc., defects or durability decrease due to decrease of insulation resistance. The recording head has a problem that non-uniformity of heat conduction causes dropout in a print or an image and shortens the life.

The present invention has been made to solve the above-mentioned conventional problems and is caused by the fact that the film formation on the electrode surface is mixed into a thin film during film formation as a peeling film or a minute abnormal discharge caused by the peeling film. It is an object of the present invention to provide an electrode member capable of preventing the film formation defect.

[0005]

In order to achieve this object, an electrode member of the present invention includes a plate-shaped member and an enclosure having an opening, the main surface of the plate-shaped member facing the opening. In addition, the plate-shaped member is housed in the enclosure, and the ratio of the area of the plate-shaped member to the projected area of the opening on the plate-shaped member is 30% or more and 97% or less.

When the main surface of the plate-like member facing the opening of the electrode member is the front surface and the main surface of the plate-like member facing the front surface is the back surface, a gap extending from the front surface to the back surface is formed. A portion of the plate-shaped member, the total surface area of the wall surface of the void formed by the void, the outer peripheral side surface of the plate-shaped member, the front surface and the back surface is equal to 2 of the area of the surface.
It is more than twice and less than 100 times.

Further, the thin film forming method of the present invention comprises an inflow pipe for introducing gas into the enclosure of any one of the plate-like members and a wire for supplying a voltage to the plate-like member, and the enclosure is provided. Decompress, while flowing the raw material gas from the inflow pipe into the enclosure, while applying a voltage from the wiring to the plate-shaped member,
The raw material gas having the electric charge is applied to a base material provided by discharging the raw material gas from the plate-shaped member to provide the raw material gas with an electric charge and separating the raw material gas from the plate-shaped member with respect to the opening. It is discharged from the opening of the enclosure to form a thin film.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the electrode member of the present invention, the ratio of the area of the plate member to the projected area of the opening on the plate member is 30.
% To 97%, the area of the electrode member with respect to the opening can be optimized, and when applied to a film forming method for forming a film on a substrate by a vapor deposition method while applying a voltage to the electrode member. In the vicinity of the outer periphery of the electrode member and the opening, a thin film formed on the base material can suppress a deposited film deposited near the outer periphery of the electrode member, and a minute abnormal discharge caused by the deposited film deposited on the electrode member and / or Alternatively, the deterioration of the quality of the thin film due to the inclusion of the deposited film in the thin film formed on the base material can be eliminated, and the film formation efficiency on the base material can be improved.

In the electrode member of the present invention, the plate member is provided with a void having a continuous void from the front surface to the back surface, and the side wall of the void portion and the pair of main surfaces of the plate member facing each other and the plate member. Since the total surface area with the outer peripheral side surface of the electrode is 2 times or more and 100 times or less than the area of only the surface facing the opening, the surface area of the electrode member can be optimized, and vapor phase deposition can be performed while applying voltage to the electrode member. When applied to a film forming method of forming a thin film on a base material by a method, it is possible to control the charge injected into the raw material gas for forming a thin film on the base material, and to perform a more efficient formation of a uniform thin film. be able to.

Further, according to the thin film forming method of the present invention, a charge is injected into the raw material gas by the electrode member to form a thin film on the base material facing the plate-like member through the opening. A film can be formed efficiently. As a result, it is possible to obtain a thin film with few film formation defects due to the inclusion of the peeling film and the minute abnormal discharge, while maintaining a high film formation rate.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the electrode member of the present invention is applied as a plasma excitation electrode in a plasma CVD method will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a configuration diagram showing a main part of an apparatus for forming a protective film of a magnetic recording medium by a plasma CVD method, and FIG. 2 is a sectional view showing the configuration of the magnetic recording medium. Is. In FIG. 2, 1 is a non-magnetic substrate, 2 is a magnetic layer formed on one main surface of the non-magnetic substrate 1, 3 is a protective film formed on the magnetic layer 2, and 4 is a protective film formed on the protective film 3. Formed slipping layer,
Reference numeral 5 is a back coat layer formed on the other main surface of the non-magnetic base material, and the magnetic recording medium 6 is composed of a back coat layer 5, a non-magnetic base material 1, a magnetic layer 2, a protective film 3, and a slipping layer 4. To be done. Hereinafter, in this embodiment, the non-magnetic base material 1 provided with the magnetic layer 2 is referred to as a magnetic base material 7, and the magnetic base material 7 provided with the protective film 3 is referred to as a magnetic recording precursor 8.

As a material applicable to the non-magnetic base material 1,
It is a polymer material such as polyethylene terephthalate, polyethylene naphthalate, and polyamide, and has a thickness of 3 to
Generally, about 15 μm is used. The magnetic layer 2 is a coating type in which a so-called magnetic ink obtained by dispersing magnetic material powder in a binder resin solution and diluted with a solvent for adjusting viscosity is applied, for example, Co-O, Co-Ni-O, Co-Cr. -A dry type in which a ferromagnetic metal such as Ni is formed by a vapor deposition method such as a reactive vapor deposition method or a reactive sputtering method is applicable, but when a film is formed by a plasma CVD method, a dry type is generally applied. To be done. The protective film 3 is a carbon film called diamond-like carbon in order to impart a function of preventing the oxidation of the ferromagnetic metal and mechanically protecting the evaporated magnetic layer in the ferromagnetic metal evaporated magnetic recording medium, and is a low molecular weight film. A hydrocarbon compound as a main raw material can be formed into a film by a plasma CVD method, and its thickness is 3 to 50.
It is about nm. For the slippery layer 4, a fluorine-containing lubricant is generally applied and can be formed by a wet coating method or a vacuum vapor deposition method.
The thickness is about 1 to 20 nm. As a material applied to the back coat layer 5, a solid lubricant such as carbon or fine particles such as silicon dioxide is a polyester resin and / or a binder resin such as nitrocellulose, for example, methyl ethyl ketone, toluene, cyclohexanol, etc., alone or mixed. Dispersed in a solution dissolved in a solvent that was formed by wet coating,
Its thickness is about 0.3 to 1 μm.

Next, the thin film forming apparatus of FIG. 1 will be described as an embodiment of the thin film forming method of the present invention. In FIG. 1, 9 is a feeding roller for feeding the magnetic base material 7, 10 is a main roller for transporting the protective film 3 formed on the magnetic base material 7 to form the magnetic recording precursor 8, and 11 is the magnetic recording precursor 8. A winding roller for winding, 12 and 13 are pass rollers, 14 is a vacuum pump, and 15 is a valve for adjusting the degree of vacuum of the film forming chamber 16. The pass roller 13 applies a predetermined DC voltage or AC voltage or a voltage obtained by superimposing them to the plasma excitation electrode 18 by the voltage applying means 17. However, since the pass roller 13 is a current path through the magnetic layer 2, the pass roller 13 is electrically insulated from the film forming chamber 16, and similarly, the pass roller 1 is also provided.
2 is also electrically insulated from the film forming chamber 16. In the present embodiment, the case where the voltage applying means 17 is connected to the pass roller 13 has been shown, but only 12 pass rollers may be connected to the voltage applying means 7, or both 12 and 13 may be connected. Since the current flowing through the layer 2 is limited, if the current is supplied from both the pass rollers 12 and 13, it is possible to form a film at a high rate. The plasma excitation electrode 18 is housed in an enclosure 20 having an opening 19 and constitutes a discharge tube 21 which is an electrode member. A metal or a ceramic material of a semiconductor region can be applied to the plasma excitation electrode 18, and the plasma generated in the plasma excitation electrode 18 leaks to the film forming chamber 16 in the enclosure 20 and the components inside the film forming chamber 16 and the middle of the process. Magnetic base material 7 and magnetic recording precursor 8
It is necessary to surround the plasma excitation electrode 18 except for the openings 19 in order to prevent the contamination of the plasma excitation electrode 18, and an insulating material having heat resistance is provided as a material to be applied. Also, 22
Is a raw material introduction pipe, and the raw material gas and the auxiliary gas are supplied to the inside of the enclosure 20 while controlling the flow rate.

Next, the operation of each component shown in FIG. 1 will be described.
With the vacuum pump 14 evacuated, the valve 15 is opened and the film forming chamber 16 is degassed, and the specified vacuum degree (for example, 1 × 10 ^-2 P
reach a). Feeding roller 9 with magnetic layer 2 outside
The magnetic base material 7 wound around is continuously conveyed from the feeding roller 9 through the pass roller 12 by the main roller 13 at a constant speed. In order to suppress the phenomenon of heat loss of the non-magnetic base material 1 and / or the magnetic layer 2 due to the temperature rise due to plasma when the protective film 3 is formed by plasma CVD, which will be described later, a refrigerant is placed inside the main roller 13. Etc. are circulated to control the temperature to a constant temperature and electrically insulated from the film forming chamber 16. Magnetic substrate 7 conveyed by main roller 13
Forms the protective film 3 in the area of the opening 19 of the discharge tube 21. That is, the organic molecule vapor that flows in from the raw material introduction tube 22 at a controlled flow rate is turned into plasma by the plasma discharge of the plasma excitation electrode 18, and passes through the opening 19 of the discharge tube 21 in the state of ions and / or radicals containing carbon and is magnetized. Base material 7
Is deposited on the magnetic layer 2 and the protective film 3 is formed to form the magnetic recording precursor 8. In this embodiment, the mixed gas of nonane and argon gas is controlled in flow rate and supplied from the raw material introduction pipe 22, and a predetermined voltage is applied between the plasma excitation electrode 18 and the pass roller 13 from the voltage application means 17. A plasma CVD diamond-like carbon protective film 3 was formed on the magnetic layer 2 to obtain a magnetic recording precursor 8. Since the plasma current generated under the above conditions flows through the magnetic recording precursor 8 and the pass roller 13, the denseness of the protective film 3 formed on the magnetic layer 2 is high. In this embodiment, the voltage applying means 17 applies the voltage only between the plasma excitation electrode 18 and the pass roller 13, but only between the plasma excitation electrode 18 and the pass roller 12, or between the plasma excitation electrode 18 and the pass rollers 12 and 13. May be between The magnetic recording precursor 8 is wound around the winding roller 11 via the pass roller 13.

Next, the relationship between the plasma excitation electrode 18 and the opening 19 in the discharge tube 21 will be described. Figure 3
4 is an example for explaining the relationship between the plasma excitation electrode 18 and the opening 19 as viewed from the magnetic substrate 7 side. In the figure,
The plasma excitation electrode 18 is housed in an enclosure 20, and the enclosure 20 has a raw material introduction tube 22 (not shown because it is hidden by the plasma excitation electrode 18) and an opening 19 only. Further, 23 is a transport direction in which the magnetic base material 7 and the magnetic recording precursor 8 are transported by the main roller 10, and 24 is a rotation axis direction of the main roller 10. As shown in the figure, it is preferable that the length in the transport direction 23 is longer than the length in the rotation axis direction 24 because the film formation time can be lengthened. This opening 1
9 is a projected area on the plasma excitation electrode 18 (actually, a plane parallel to the plasma excitation electrode 18) (when the projection surface of the opening 19 is rectangular, the length in the transport direction 23 and the length in the rotation axis 24 direction). Of the plasma excitation electrode 18 facing the opening 19 is defined as an opening area ratio, and the plasma excitation electrode 18 facing the opening 19 is shaded. The area of the shaded area is defined as the apparent area. By the way, as a means for increasing the plasma generation efficiency by increasing the contact area with the raw material vapor, a punched steel plate, a sintered metal, a laminated expanded metal, a porous metal such as a foam metal is applied to the plasma excitation electrode 18 as an electrode. It The apparent area defined above refers to the area of the electrode surface of the plasma excitation electrode 18 of FIG.
Is not included. By the way, if the efficiency of generating plasma from the plasma excitation electrode 19 is a problem, it is also necessary to consider the total surface area of the plasma excitation electrode 18 as described above.
That is, the total surface area refers to the electrode outer peripheral surface of the plasma excitation electrode 18, the surface facing the opening 19 of the porous metal of the material applied to the void processing portion 25 and its back surface, and the void inner peripheral side surface of the void processing portion 25. When the ratio of the total surface area of the plasma excitation electrode 18 to the apparent area is defined as the total area ratio, the total area ratio also becomes a factor in forming the plasma CVD film. Therefore, it is a technical idea to suppress the film formation defect by optimizing the opening area ratio and the total area ratio, and the opening area ratio is preferably in the range of 30% or more and 97% or less. It is more preferable to set the total area ratio to 2 times or more and 100 times or less under the above conditions.

Next, polyethylene terephthalate having a width of 500 mm and a thickness of 6 μm is used as the non-magnetic substrate 1, and a ferromagnetic metal thin film containing Co as a main component is formed on the non-magnetic substrate 1 to a thickness of 150 nm by a vapor deposition method. On the magnetic base material 7 having the magnetic layer 2 formed as described above, a diamond-like carbon protective film 3 having a Vickers hardness of about 25 GPa is plasma-formed by using a raw material in which the mixing ratio of nonane as a carbon source and argon as an auxiliary gas is 2: 1. Experiments and results of film formation by the CVD method will be described. The voltage applying means 17 is applied to the plasma excitation electrode 18.
The application condition from 2 was kept constant at 2 MHz at 2 MHz, and the characteristics of diamond-like carbon were evaluated using the opening area ratio of the plasma excitation electrode 18 and the total area ratio as parameters.
As a method of changing the opening area ratio and the total area ratio, the material applied to the plasma excitation electrode 18 is a stainless steel punched steel plate (hereinafter referred to as SUS punched plate), a stainless multilayer expanded metal (hereinafter, the number of layers is n). Then, n layer expanded SUS) and stainless sintered metal (hereinafter referred to as SUS sintered metal) were appropriately selected and used. The side area of the void of the void processed portion 25 needs to be calculated in order to calculate the total area ratio, but it is calculated from the measured porosity values assuming that the same void is provided over the entire surface of the void processed portion 25. The volume and weight are measured and calculated from the specific gravity of the material applied to the void processing portion 25, but the simplest method is to use the catalog value of the maker to purchase.

The protective film 3 was formed by using the plasma excitation electrodes 18 having the opening area ratios of 30%, 60% and 97% and the total area ratios of 2, 50 and 100 times. 10
1-110 were obtained. The combination of the material of the plasma excitation electrode 18, the opening area ratio, and the total area ratio is shown in (Table 1).

As comparative examples, opening area ratios of 29% and 98
%, The protective film 3 was formed using the plasma excitation electrodes 18 having a total area ratio of 1.6 times, 50 times, and 110 times.
201-204 were obtained. Material of the plasma excitation electrode 18,
The combination of the opening area ratio and the total area ratio is shown in (Table 1).

The sample No. obtained in the above examples. 101-1
10 and the sample No. 10 obtained in the comparative example. For evaluation of Nos. 201 to 204, a practical reliability test was conducted after taking the form of the magnetic recording medium 6. First, in order to take the form of the magnetic recording medium 6, as the back coat layer 5 of each sample, a dispersion liquid in which carbon black is mixed as a filler in a solution in which a polyester resin and a nitrocellulose resin are mixed is prepared from methyl ethyl ketone, toluene and cyclohexanone. It was diluted with a mixed solvent and applied to a dry thickness of 1 μm, and as a slipping layer 4, a fluorinated carboxylic acid-based lubricant was applied to a dry thickness of 3 nm.
The magnetic recording medium 6 created in this way has a width of 6.35 m.
After cutting into m and 70 m in length and mounting in a digital video cassette, dropout and durability were evaluated using a device obtained by modifying a commercially available digital video camera.
The dropout was measured by measuring a dropout of 3 μsec 6 dB for 10 minutes and evaluating the average value for 1 minute. The number of dropouts in which the image quality is clearly deteriorated when reproducing the image signal is about 240 per minute on average, and therefore the number of dropouts is 20 in consideration of the image signal, the audio signal and the data signal.
0 was used as the acceptance criterion. In this example, the image durability was measured by repeatedly reproducing a signal in which signals were recorded at 5 locations for 1 minute in the same cassette, and evaluated by the number of passes in which the output was reduced by 6 dB. The pass / fail judgment criterion for the number of passes is, for example, at least 5000 times, assuming that the data signal is frequently accessed during reproduction,
In this embodiment, 5000 times is adopted. The results of evaluating dropout and durability in this manner are shown in (Table 1).

[0021]

[Table 1]

Dropout and durability are both evaluated from different viewpoints of the film quality of the diamond-like carbon film.
A comparison is made from the viewpoint of the opening area ratio and the dropout and durability, and a comparison is made from the viewpoint of the total area ratio and the dropout and durability.

First, considering the relationship between the opening area ratio and the dropouts with the same total area ratio of the parameters, the dropout number tends to decrease as the total area ratio of the parameter increases, and the dropout increases as the opening area ratio increases. It can be seen that the number of outs tends to be low. Looking at the tendency of the dropout number with respect to the opening area ratio when the total area ratio is 50 times and the total area ratio is 97 times, the opening area ratio is 60%.
Since the change above is small, it is assumed that the opening area ratio is about 60% and stable in terms of dropout.

The smaller the opening area ratio, the smaller the area of the plasma excitation electrode 18. When the area of the plasma excitation electrode 18 decreases, the absolute amount of the raw material plasma supplied to the magnetic substrate 7 decreases. Therefore, it is assumed that the film forming efficiency of the protective film 3 (diamond-like carbon film) is lowered and the film quality is deteriorated. On the contrary, as the value of the opening area ratio increases, the absolute amount of the raw material plasma supplied from the plasma excitation electrode 18 increases, which indicates that a diamond-like carbon film having a dense film quality tends to be formed. There is. However, due to the relationship between the number of dropouts and the opening area ratio at the total area ratio of 50 times, the sample No. 201 and sample No. 102, and sample No. 109 and sample No. Looking at the relationship with Sample No. 204, Sample No. 102
The dropout number between 106 and 109 is sharply changed compared to the rate of change, but it can be assumed that the cause is as follows. First, the sample No. 201 and sample No. 10
The relationship with Sample No. 2 is as follows. In 201, the supply amount of the raw material plasma is severely insufficient, and it is difficult to form the diamond-like carbon film as a uniform film. It is assumed that one of the reasons is that the quality of the film becomes fragile by being mixed in the film, and therefore it is understood that the opening area ratio is preferably 30% or more. In addition, the sample No. 109 and sample No. The relationship with Sample No. 204 is as follows. In 204, since the gap between the opening 19 and the plasma excitation electrode 18 is small, the source gas hits the inner wall of the enclosure 20 near the boundary of the opening 19 and wraps around the outer peripheral surface of the plasma excitation electrode 18, and the source plasma is deposited on the outer peripheral surface. It is assumed that the deposited film peels off and mixes into the diamond-like carbon film as a peeled film and / or causes the abnormal discharge to cause damage to the diamond-like carbon film and / or the magnetic layer 2. Therefore, it is understood that the upper limit of the opening area ratio is preferably 97% or less.

Next, considering the relationship between the opening area ratio and the durability with the total area ratio of the parameters being the same, there is a tendency that the optimum value of the opening area ratio is around 60% and the total area ratio that is the parameter. Also, there is a tendency that the optimum value is exhibited around 50 times.

Note that the sample No. 1 has a tendency of durability with respect to the opening area ratio at a total area ratio of 50 times. 201 and sample No. 1
02 and sample No. 109 and sample No. Since the change ratio of 204 is steep like the dropout described above, the same cause as described above is assumed, and therefore the aperture area ratio is 3
It can be seen that 0% or more and 97% or less is preferable. Sample No. 201 and sample No. 102 and the sample No. 109 and sample No. From the point that the latter is overwhelmingly larger in the amount of change from 204, the inclusion of the exfoliation film in the diamond-like carbon film than the thinness and / or non-uniform film formation of the diamond-like carbon film. And / or the influence of abnormal discharge is assumed to be greater.

Next, the relationship between the total area ratio and the number of dropouts will be considered with the opening area ratio as a parameter. The number of dropouts tends to decrease as the total area ratio increases. This tendency is that as the total area ratio increases, the ratio of the raw material gas turned into plasma at the plasma excitation electrode 18 increases, so that sufficient raw material plasma is supplied to the magnetic base material 7 during film formation to form a dense diamond-like carbon film. It is assumed that the film can be formed.

Sample No. 1 having an opening area ratio of 60% was kept constant. 202, 104, 105, 106, 107, 20
Considering Sample No. 3, 202 and sample No.
The change ratio of the dropout number between the sample No. 104 and the sample No.
104 and sample No. It is much steeper than the fluctuation ratio with respect to 105 whether the supply amount of the raw material plasma to the magnetic base material 7 is insufficient due to the low efficiency of plasma formation, and /
Alternatively, it is assumed that the raw material gas that has not been turned into plasma is mixed into the raw material plasma and the unreacted raw material in the diamond-like carbon film is trapped. Therefore, the total area ratio is preferably twice or more, and the sample No. 104 and sample N
o. Considering the fluctuation ratio with 105, 10 times or more is desirable.

Next, the relationship between the durability and the total area ratio will be considered using the opening area ratio as a parameter. From the viewpoint of durability, it can be seen that the opening area ratio of 60% is superior to any total area ratio or any total area ratio. Therefore, as described above, the opening area ratio is preferably around 60%. . In addition, the sample No. under the condition that the opening area ratio is constant at 60%. 202, 104, 105, 106, 107, 20
For sample 3, In Nos. 202, 104, and 105, the same tendency as the above-mentioned relationship between the number of dropouts and the total area ratio is seen, but the sample No. Even in 202, the durability reference value in this embodiment is satisfied. On the other hand, sample N
o. 107 and sample No. The decrease variation ratio between the sample No. 203 and the sample No. 106 and sample No. 106. There was almost no change with the fluctuation ratio between the values of 107 and 107, but the value was below the reference value of durability in this example. This is because the supply amount of the raw material gas increases as the total area ratio increases, and the raw material gas that has not been turned into plasma also mixes into the diamond-like carbon film, and / or the voltage applying means 17 increases the total area ratio. It is assumed that the factor is that the supply gas amount is insufficient (that is, the current density per unit area decreases), and the plasma generation of the source gas decreases. In this example, the standard value of durability was satisfied when the total area ratio was up to about 100 times, but was lower than the reference value when the total area ratio was 110 times. Therefore, the upper limit of the total area ratio is about 100 times. I understood.

From the above, it is found that the opening area ratio of the plasma excitation electrode 18 is preferably 30% or more and 97% or less, and if it is out of this range, the variation ratio in both the dropout number and the durability may sharply decrease. found. Also,
If the total area ratio is less than 2 times, the dropout number drops sharply, but the fluctuation amount is gentler than the opening area ratio, and it is possible that the characteristic deterioration due to the total area ratio can be absorbed by optimizing the opening area ratio. is there. However, it can be said from the above-mentioned embodiment that the total area ratio is preferably 2 times or more and 100 times or less.

In this embodiment, the plasma excitation electrode 18
A sample was prepared using the material of (1) above with a SUS punched plate, a laminated expanded metal, and a sintered metal, but almost the same results were obtained even if a combination of the above materials or a foam metal was used.

Further, in this embodiment, the plasma excitation electrode 18
For the outer shape of, the electrode shape with chamfered squares was applied,
Even a rectangular shape can be applied. However, if the outer shape is rectangular, current is likely to concentrate at the corners and abnormal discharge is likely to occur. Therefore, it is preferable to chamfer as in this embodiment. The outer shape may be an elliptical shape, but when the elliptical shape is applied, non-uniformity occurs in the axial direction 24. Therefore, a chamfered rectangular shape as in this embodiment is preferable. The shape of the void processing portion 25 is also elliptical in this embodiment, but the external shape of the plasma excitation electrode 18 may be either a similar shape or a rectangular shape.

In this embodiment, the protective film 3 is formed on the magnetic base material 7 before the back coat layer 5 is formed, but after the back coat layer 5 is formed on the magnetic base material 7 in advance. Of course, the protective film 3 may be formed.

(Embodiment 2) Next, another embodiment using the electrode member of the present invention will be described. FIG. 4 is a conceptual configuration diagram of a main part of an apparatus for manufacturing an interlayer insulating film of a semiconductor element as another embodiment of the thin film manufacturing method of the present invention. In the figure,
Vacuum pump 14, valve 15, voltage applying means 17, plasma excitation electrode 18, opening 19, enclosure 20, discharge tube 2
1. The raw material introduction pipe 22 is the same as the plasma CVD film forming unit and the like described in Embodiment 1 with reference to FIG. The only difference from FIG. 1 is the carrying roller 32 that carries the substrate carrier 31, and the substrate 26 is carried by the substrate carrier 31 through the film forming chamber 16 at a constant speed. Film forming chamber 16
Prevents the raw material from mixing in a mounting chamber (not shown) for mounting the substrate 26 on the substrate carrier 31 and an electrode film forming chamber (not shown) for forming an electrode on the insulating film substrate 28 from the substrate carrier 31. Therefore, it is isolated. In this embodiment, FIG.
As shown in FIG. 6, a model substrate 30 in which a silicon substrate is applied to the substrate 26, silicon oxide is applied as the interlayer insulating film 27 on the silicon substrate 26, and aluminum is formed as the electrode 29 formed on the interlayer insulating film 27. Then, the formation of the interlayer insulating film 27 was examined. Tetraethoxysilane was introduced into the material gas for the interlayer insulating film 27 at a pressure of 40 Pa from the material introducing pipe 22, and a silicon oxide thin film was formed to a thickness of 2 μm by the plasma CVD method. After forming the interlayer insulating film 27, the electrode 2
9 was formed into a film with a thickness of 5 μm by a sputtering method, and sample No. 111-1
20 and sample No. 20. 270-212 were obtained. The plasma excitation electrode 18 used in this example is the same as the electrode used in Example 1.

In order to evaluate the characteristics of the interlayer insulating film 27 of the model substrate 30 in which the interlayer insulating film 27 of 2 μm is formed on the silicon substrate 26 and the electrode of 5 μm is formed in this way,
The initial resistance value immediately after cutting and the resistance value after standing for 7 days in an atmosphere of 80 ° C. and 90% relative humidity were each measured by applying a voltage of DC 12 V, and the average value was measured. For each sample No. The measurement results are shown in (Table 2) together with the material of the plasma excitation electrode 18.

The higher the resistance value and the rate of change of the interlayer insulating film, the more preferable, but from the practical point of view, the initial resistance value is 200 kΩ or more, and the resistance value after leaving is 100 kΩ.
That is, a resistance change rate of 50% or more is generally required, and therefore, in the present embodiment, the satisfaction of the three conditions was used as the evaluation criterion.

[0037]

[Table 2]

First, the relationship between the initial resistance value and the opening area ratio and the total area ratio shown in (Table 2) will be described. Regarding the relationship between the initial resistance value and the opening area ratio using the total area ratio as a parameter, the initial resistance value of 200 kΩ is satisfied under the condition that the opening area ratio is 30% or more and 97% or less. On the other hand, Sample No. with an opening area ratio of 29%. The reason why the initial resistance value of 205 is low is that the area of the plasma excitation electrode 18 is small and the absolute amount of the source plasma is insufficient, and it is difficult to form a uniform silicon oxide film. It is assumed that either of them is mixed in the insulating film 27 and deteriorates the film quality. The opening area ratio is 98
% Of sample No. The reason why the initial resistance value of 208 is low is that when the source gas passes through the gap between the plasma excitation electrode 18 and the opening 19, it hits the inner wall of the enclosure 20 and rebounds, and a thin film is deposited on the plasma excitation electrode 18, and the deposited thin film. Is assumed to be a peeling film and mixed in the interlayer insulating film 28.
Therefore, the opening area ratio is preferably 30% or more and 97% or less,
It can be seen that around 60% is desirable.

Next, regarding the relation between the initial resistance value and the total area with the opening area ratio as a parameter, the opening area ratio is 29% and 9%.
8% of sample No. 206 and 207, sample No. with a total area ratio of 110 times. Other than 207, the initial resistance value of 200 kΩ or more is satisfied. Sample No. 206 and 207
It is presumed that the reason why the resistance value does not satisfy the initial resistance value is due to the above. Sample No. It is assumed that the main reason why 207 does not satisfy the initial resistance value is that the total area ratio is large, so that the current density is lowered and there is a sign of insufficient ability to turn the raw material into plasma. However, the sample No. The initial resistance value of 207 is 195 kΩ, which does not reach 200 kΩ, and the influence of the cause assumed to be the current density is extremely small. From the above results, it can be said that the total area ratio is 100 times or less in terms of the initial resistance value according to the criteria of the present embodiment.
Even if it is 110 times, it can be applied for life depending on the application.

From the relationship between the resistance change rate and the opening area ratio using the total area ratio as a parameter, it can be seen that the value of the resistance change rate increases almost uniformly with respect to the opening area ratio. 111, 112, 113, 114, 116, 1
The resistance change rates of all 17, 118, 119, 120, 206, and 207 satisfy 50% or more of the evaluation reference value of this embodiment. Therefore, although the dependency of the resistance change rate on the opening area ratio is numerically satisfied, the sample No. 205 and 11
2 and the sample No. Since the inclination between 119 and 208 is peculiar, the sample No. It suggests that the film quality of the interlayer insulating film 27 of 205 and 208 has discontinuity. As can be seen from the values shown in (Table 2), the two samples have low initial resistance values, and the low initial resistance values mean that there are defects in the interlayer insulating film 27 as described above, and Even if a reliability test is performed on a film having a low resistance value, it is considered that the change is smaller than that of an insulating film having a good film quality. Further, in the dependence of the total area ratio of the resistance change rate with the opening area ratio as a parameter, the total area ratio of Sample No. 2 is less than twice. In Sample No. 206, the rate of change in resistance sharply decreased, indicating that the interlayer insulating film 27 was not uniformly formed, and the total area ratio exceeded 100 times. Also in 207, the rate of resistance change sharply decreases, so it is expected that abnormal discharge due to the peeling film or the peeling film is mixed in the interlayer insulating film 27. Therefore, from these facts, the opening area ratio is preferably 30% or more and 97% or less, and more preferably about 60% or more,
The total area ratio is preferably 2 times or more and 100 times or less, and more preferably 10 times or more.

Although the protective film of the magnetic recording medium and the interlayer insulating film used for the semiconductor have been described in the above embodiments, the durability, the conversion efficiency, the current carrying capacity and the durability of the liquid crystal insulating film, the photoelectric conversion element, the superconducting thin film, etc. Improvement of life is recognized.

[0042]

As described above, when the electrode member of the present invention is applied to a thin film forming method for forming a film while applying a voltage,
A thin film having a uniform film quality, high density, and high film formation efficiency, because it is possible to suppress adverse effects such as a minute abnormal discharge caused by a film deposited on the electrode member and / or the film being mixed in the formed film. Can be formed. As a result, good magnetic properties can be maintained for a long period of time when applied to the formation of a protective film of a magnetic recording medium, and a highly reliable thin film can be obtained when applied to the formation of an interlayer insulating film of a semiconductor.

[Brief description of drawings]

FIG. 1 is a configuration diagram of essential parts showing an embodiment of a thin film manufacturing apparatus.

FIG. 2 is a conceptual sectional view of a magnetic recording medium.

FIG. 3 is a plan view of a discharge tube.

FIG. 4 is a main part configuration diagram showing another embodiment of the thin film manufacturing apparatus.

FIG. 5 is a conceptual sectional view of a semiconductor.

[Explanation of symbols]

1 Non-magnetic base material 2 Magnetic layer 3 protective film 6 Magnetic recording media 9 Feeding roller 10 Main roller 11 winding roller 12 pass rollers 13 Pass Roller 16 Film forming chamber 18 Plasma excitation electrode 19 opening 20 enclosure 21 discharge tube 25 Void processing part 26 Silicon substrate 27 Interlayer insulation film 29 electrodes

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor, Toshihiro Hayase             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 4K030 BA28 BA44 CA04 CA07 CA12                       EA06 GA14 KA15 LA20                 5D112 AA07 BC05 FA10

Claims (3)

[Claims] 1. A plate-shaped member and an enclosure having an opening, a main surface of the plate-shaped member facing the opening, the plate-shaped member being housed in the enclosure, An electrode member, wherein a ratio of an area of the plate-shaped member to an area projected on the plate-shaped member is 30% or more and 97% or less. 2. When the main surface of the plate-shaped member facing the opening is the front surface and the main surface of the plate-shaped member facing the front surface is the back surface, a void portion continuous from the front surface to the back surface is formed in the plate. For the wall-shaped member, the wall surface of the void formed by the void,
The electrode member according to claim 1, wherein a total total surface area of the outer peripheral side surface, the front surface, and the back surface of the plate-shaped member is 2 times or more and 100 times or less of an area of the surface. 3. An inflow pipe for flowing gas into the enclosure of the plate-like member according to claim 1, and a wire for supplying a voltage to the plate-like member, and decompressing the enclosure. A raw material gas is flown into the enclosure from the inflow pipe, a voltage is applied to the plate-shaped member from the wiring, the raw material gas is discharged from the plate-shaped member, and the raw material gas is charged. A method for forming a thin film, comprising: discharging a charged raw material gas from an opening of the enclosure to form a thin film on a base material provided on the opposite side of the plate member with respect to the opening.