JPH097169A - Thin film forming device - Google Patents

Abstract

PURPOSE: To eliminate the need for interrupting film forming work and cleaning a microwave transmission window by providing a thin film forming device with a deposition preventive plate which can transmit microwaves freely exchangeably so as to face the microwave transmission window disposed at the microwave reaction tube of a plasma reaction plasma reaction tube. CONSTITUTION: The microwaves through a waveguide are introduced through the microwave transmission window 2a of the plasma reaction tube 2 to which reactive gases are supplied. The plasma is then excited and cyclotron resonance is induced by the magnetic field by a coil 3 for ECR. The film formation by plasma CVD is thus executed. The reaction tube 2 is internally freely exchangeably provided with the deposition preventive plate 4 which is supplied from a deposition preventive plate holder 5 via push rods 6, 9 and is discharged to a deposition preventive plate recovering pocket 13 so as to face the window 1a, thereby, the deposition of carbon, etc., accompanying the CVD work on the deposition preventive plate 4 is prevented. Accordingly, the need for interrupting the film forming work, removing the window 2a from the reaction tube 2 and cleaning the window is eliminated. The continuation of the good CVD film forming work without interruption is thus made possible.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an apparatus for forming, for example, a diamond-like carbon film.

[0002]

BACKGROUND OF THE INVENTION In a magnetic recording medium such as a magnetic tape, due to a demand for high density recording, a magnetic layer provided on a support is not a coating type using a binder resin and does not use a binder resin. A metal thin film type has been proposed. That is, there has been proposed a magnetic recording medium having a magnetic layer formed by a wet plating means such as electroless plating or a dry plating means such as vacuum deposition, sputtering or ion plating. This type of magnetic recording medium has a high filling density of a magnetic material and is suitable for high-density recording.

In order to protect the metal magnetic film in this type of magnetic recording medium, it has been proposed to provide various protective films on the surface. For example, a diamond-like carbon film is one of these proposals. There are various means for providing the diamond-like carbon film on the surface. For example, hot filament CVD device, photo CVD device, RF plasma CVD device, microwave plasma CV
C such as D device and ECR microwave plasma CVD device
There is a VD (Chemical Vapor Deposition) device.

Among them, ECR microwave plasma CVD
The device is most widely used because it can form a particularly good protective film. Here, FIG. 6 shows a schematic structure of the ECR microwave plasma CVD apparatus. Figure 6
Among them, 31 is a raw material of a magnetic recording medium in which a Co metal magnetic film having a thickness of 1600Å is provided on the surface of a support, 32 is a vacuum chamber, 3
3a is a supply side roll of the original fabric 31, 33b is a winding side roll of the original fabric 31, and 34 is a cooling can roll.
Is configured to travel from the supply side roll 33a through the cooling can roll 34 to the winding side roll 33b and be wound up.

Reference numeral 35 is a plasma reaction tube provided to face the cooling can roll 34, 35a is a conical microwave transmission window made of quartz glass, and 36 is a reaction gas (for example,
Pipe for supplying mixed gas of methane and hydrogen, 37 is microwave waveguide, 38 is microwave (2.45 GHz)
The oscillator 39 is an ECR coil having an ECR magnetic field of 875 Gs. The port of the reaction gas supply pipe 36 is located inside the plasma reaction tube 35 and near the cooling can roll 34.

In this apparatus, the reaction gas is supplied to the pipe 36.
From inside the plasma reaction tube 35 and the waveguide 37
By introducing a microwave of wavelength λ into the plasma reaction tube 35 to excite the plasma and apply a magnetic field in the ECR coil 39 in the same direction as the traveling direction of the microwave to cause cyclotron resonance and generate ECR microwave plasma. CVD
Is to be done.

By the way, in such an ECR microwave plasma CVD apparatus, carbon particles are gradually adhered and deposited on the inner surface of the microwave transmission window 35a, and accordingly, the amount of microwave transmission is reduced. Then, after a certain amount of time has passed, the required amount of permeation cannot be obtained, and the microwave cannot be sufficiently supplied into the plasma reaction tube 35. Therefore, the film forming rate is not constant and becomes unstable, and if the work is continued as it is, a defect may occur in the product.

Therefore, at present, the adhesion of carbon particles
Before the influence of deposition cannot be ignored, the work is interrupted, for example, every one hour, and the microwave transmission window 35a is once removed to perform cleaning, but a reduction in work efficiency cannot be avoided.

[0009]

DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a thin film forming apparatus which does not require cleaning of a microwave transmitting window during a film forming operation and can perform the film forming operation continuously and efficiently. An object of the present invention is an apparatus for forming a thin film on a support located at a position facing a plasma reaction tube by a plasma CVD method, and facing a vacuum chamber and a support arranged in the vacuum chamber. And a plasma reaction tube provided with a microwave transmission window on one end side thereof, a reaction gas supply means for supplying a reaction gas into the plasma reaction tube, and a plasma reaction tube in the plasma reaction tube through the microwave transmission window. A microwave oscillating means for supplying microwaves, a protective plate for transmitting microwaves, which is provided in the plasma reaction tube so as to be opposed to the microwave transmitting window and is exchangeable, and a used protective plate is not used. This is achieved by a thin film forming apparatus, characterized in that it comprises an adhesion preventing plate exchanging means for exchanging the same.

Further, there is provided an apparatus for forming a thin film on a support located at a position facing a plasma reaction tube by a plasma CVD method, the position facing a vacuum chamber and a support arranged in the vacuum chamber. And a plasma reaction tube provided with a microwave transmission window on one end side thereof, a reaction gas supply means for supplying a reaction gas into the plasma reaction tube, and a microwave reaction tube inside the plasma reaction tube through the microwave transmission window. A microwave oscillating means for supplying a microwave, an anti-adhesion plate that is provided in the plasma reaction tube so as to be exchangeable and faces the microwave transmission window, and an anti-adhesion plate that holds a predetermined number of the anti-adhesion plates. A holding means, an adhesion-preventing plate sending-out means for receiving an unused adhesion-preventing plate from the holding-preventing plate holding means, and sending it out facing the microwave transmission window, and collecting the used adhesion-preventing plate. That is achieved by a thin film forming apparatus characterized by comprising; and a deposition preventing plate recovery means.

In particular, it is an apparatus for forming a thin film on a support located at a position facing a plasma reaction tube by a plasma CVD method, and a position facing a vacuum chamber and a support provided in the vacuum chamber. And a plasma reaction tube provided with a microwave transmission window on one end side thereof, a reaction gas supply means for supplying a reaction gas into the plasma reaction tube, and a microwave reaction tube inside the plasma reaction tube through the microwave transmission window. A microwave oscillating means for supplying a microwave, an anti-adhesion plate that is provided in the plasma reaction tube so as to be exchangeable and faces the microwave transmission window, and an anti-adhesion plate that holds a predetermined number of the anti-adhesion plates. The holding means, the adhesion-preventing plate sending-out means for receiving an unused adhesion-preventing plate from the holding means, and sending it to the front of the microwave transmitting window, and the used protection plate are rotated. And a protection plate recovery means, the protection plate holding means and the protection plate recovery means are provided at positions sandwiching the microwave transmission window, and the protection plate retention means and the protection plate recovery means are provided. According to a thin film forming apparatus, the deposition preventing plate is sent out from the deposition preventing plate holding means side to the deposition preventing plate collecting means side by being guided by a rail stretched between the means and the means. To be achieved.

That is, according to the present invention, since the deposition plate for transmitting microwaves is provided on the front surface of the microwave transmission window in a replaceable manner, the microwave transmission window is not polluted without affecting the supply of microwaves. Can be prevented. Therefore,
It is not necessary to remove the microwave transmission window for cleaning during film formation work, and simply replace the deposition-prevention plate with an unused one. It is possible to omit the trouble of making a vacuum state, and it is not necessary to stop the film forming operation, and the film forming operation can be continuously and efficiently performed.

In the above thin film forming apparatus, the rail is provided with a hooking portion for stopping an unused adhesion preventing plate sent by the adhesion preventing plate sending means in front of the microwave transmitting window. It is preferable. That is, the unused attachment-preventing plate that is sent out is automatically set to a fixed position by the action of the hook portion, so that the position can be easily adjusted. In addition, a hole is formed in the center of the adhesion-preventing plate, and the tip of the adhesion-preventing plate collecting means is wider than the diameter of the hole formed in the adhesion-preventing plate, and the rail position is adjusted. A shaft is provided that protrudes and retracts beyond, and after the tip of the shaft is inserted into the hole of the used deposition-prevention plate at the collection position, it is opened and forcibly used. It is preferable that the rail is separated from the rail to be collected. As a result, the used deposition preventive plate can be collected more reliably.

The apparatus of the present invention is used, for example, for forming a diamond-like carbon film. The reaction gas used for forming the diamond-like carbon film is, for example, a chain hydrocarbon such as methane, a cyclic hydrocarbon such as benzene or cyclohexane, or a mixture of these hydrocarbons and a nitrogen compound such as nitrogen or ammonia. , Or pyrazine, pyrazolidine, pyrazoline, pyrazole, pyridine, pyridazine, pyrimidine, piperidine, piperazine, imidazole, pyrrole, or a hydrocarbon-based one such as nitrogen-containing cyclic hydrocarbon such as homologues and derivatives thereof.

The present invention is used, for example, to form a diamond-like carbon film on a metal thin film type magnetic film. The support in the magnetic recording medium may be magnetic or non-magnetic. Generally, it is non-magnetic. For example, polyester such as PET, polyamide, polyimide, polysulfone, polycarbonate,
An olefin resin such as polypropylene, a cellulosic resin, a polymer material such as a vinyl chloride resin, an inorganic material such as glass or ceramic, and the like are used. On this support, a metal thin film type magnetic film is provided by dry plating means such as vapor deposition or sputtering. Examples of the material of the magnetic particles forming the metal thin film type magnetic film include Fe and C.
o, Ni, and other metals, Co-Ni alloy, Co-Pt
Alloy, Co-Ni-Pt alloy, Fe-Co alloy, Fe-
A Ni alloy, an Fe-Co-Ni alloy, an Fe-Co-B alloy, a Co-Ni-Fe-B alloy, a Co-Cr alloy, or those containing a metal such as Al is used.

The present invention is not limited to the formation of the protective film of the magnetic recording medium. Only a typical example is given.

[0017]

1 to 4 show a thin film forming apparatus (E) according to the present invention.
FIG. 1 is a plan view of the main part of the ECR microwave plasma CVD device, FIG. 2 is a front view of the main part of the device as seen from the cooling can roll side, and FIG. FIG. 4 is a plan view of relevant parts of the device showing a situation where the protection plate is being replaced, and FIG. 4 is a plan view of relevant parts of the device showing a condition where replacement of the protection plate has been completed.

ECR microwave plasma CV of this embodiment
Since the basic configuration of the D device is substantially the same as that of the conventional device described above, except for the main part, the description of the entire structure will be omitted here, and only the main part will be described in detail. In each drawing, reference numeral 1 denotes a vacuum chamber, and inside thereof, a supply side roll, a winding side roll, a cooling can roll and the like of the raw material of the magnetic recording medium are provided as in the conventional apparatus of FIG.

Reference numeral 2 is a plasma reaction tube provided opposite to the cooling can roll, and 2a is a conical microwave transparent window made of quartz glass. The conventional apparatus shown in FIG. 6 faces the microwave transparent window 2a. Similarly to the above, a microwave oscillator and a microwave waveguide are provided. Reference numeral 3 is an ECR coil provided around the plasma reaction tube 2. Reference numeral 4 is a disc-shaped protection plate made of quartz with a thickness of several mm, and 5 is a protection plate 4.
The deposition-preventing plate 4 is previously housed in the holder 5 in a required number according to the time for film formation.

Reference numeral 6 denotes a push rod penetrating the end face of the holder 5 so that the push rod 6 can be displaced while maintaining airtightness. Reference numeral 7 denotes a deposition-prevention plate extruded plate attached to the tip of the push rod 6.
Reference numeral 8 is a knob for operating the push rod. Reference numeral 9 is a push rod that pushes the deposition-inhibitory plate 4 sent from the holder 5 to a fixed position, that is, the front position of the microwave transmission window 2a. The push rod 9 penetrates the side wall of the plasma reaction tube 2 and is provided so as to be displaced while maintaining airtightness. An arc-shaped fork 10 corresponding to the diameter of the deposition-inhibitory plate 4 is provided at the tip of the push rod 9. A knob 11 for operation is attached to the other end. The push rod 9 is coated with a fluororesin to prevent malfunction due to the adhesion of carbon particles. The push rods 6 and 9 can be operated either manually or automatically.

Reference numerals 12a and 12b are a pair of stainless rails provided at intervals corresponding to the diameter of the deposition preventive plate 4. The facing surfaces of the rails 12a and 12b are concave so that the attachment-preventing plate 4 having rounded edges can be reliably held from both sides. The rails 12a and 12b are the holder 5
Through the microwave transmission window 2a from the position facing the opening of
It extends to the position of the protection plate recovery pocket 13, and the protection plate 4 is configured to be guided by the rails 12a and 12b so as to be able to move from the holder 5 to the protection plate recovery pocket 13. The rails 12a and 12b are provided so that the distance between the deposition preventing plate 4 and the microwave transmission window 2a that moves along the rails 12a and 12b is about 0.5 to 20 mm.

Numerals 14a and 14b are a convex portion and a concave portion respectively formed on the facing surfaces of the rails 12a and 12b, and by a locking mechanism composed of the convex portion 14a and the concave portion 14b,
The deposition preventive plate 4 is temporarily fixed at the front position of the microwave transmission window 2a. That is, since the unused attachment-preventing plate 4 sent out by the push rod 9 is temporarily depressed by the depth of the recess 14b at the position where the latching mechanism is provided, it is not necessary to perform a troublesome position adjustment. .

Reference numeral 15 is a partition wall for preventing the deposition preventive plate 4 from falling into the plasma reaction tube 2, and 16 is an unused deposition preventive plate 4.
It is a fixed and adhesion-preventing plate for preventing the stain of the. In the ECR microwave plasma CVD apparatus configured as described above, the film forming operation is started from the state shown in FIGS. Then, when a predetermined time has passed and the deposition prevention plate 4 set on the front surface of the microwave transmission window 2a becomes dirty, it is replaced with an unused one. Replacement of the deposition preventive plate 4 is performed as follows.

First, push the knob 11 to move the rail 12
An unused adhesion-preventing plate 4 preset between a and 12b
Send out. As shown in FIG. 3, the unused deposition-inhibiting plate 4 contacts the used deposition-inhibiting plate 4 and pushes it out from the fixed position. Then, the used attachment plate 4 is the rail 12
It separates from a and 12b and falls into the attachment-prevention plate recovery pocket 13.

On the other hand, the unused adhesion-preventing plate 4 includes rails 12a,
It stops at the position of the hooking mechanism provided between 12b. After the unused deposition-inhibiting plate 4 is set in place, the knob 1
Pull 1 to retract push rod 9 to its original position. Subsequently, as shown in FIG. 4, the knob 8 is pushed to push out the unused attachment-preventing plate 4 housed in the holder 5, and the leading one is set between the rails 12a and 12b. Of course, film formation is also performed during this replacement work.

As described above, the ECR microwave plasma CVD apparatus of the present embodiment is constructed so as to prevent the microwave transmission window 2a from being soiled by repeatedly replacing the deposition preventive plate 4 during the film forming operation. So, microwave transmission window 2
It is not necessary to interrupt the film forming operation for cleaning a, and it is possible to obtain a product of excellent work efficiency and high quality. Next, in order to confirm the effectiveness of the ECR microwave plasma CVD apparatus of this example, a diamond-like carbon film was formed under the following conditions and changes in the film formation rate were examined. The results are shown. The comparative example is the data when the diamond-like carbon film was continuously formed without using the deposition preventive plate, directly exposing the microwave transmission window to plasma, and cleaning.

[Conditions] Microwave frequency: 2.45 GHz Microwave output: 600 W ECR magnetic field: 875 Gs Reaction gas: CH ₄ (50 sccm) Degree of vacuum before starting film formation: 4.0 mTorr Raw material (thickness): PET (10 μm) Original fabric running speed: 1 m / min Deposition plate diameter: 80 mm Deposition plate thickness: 3 mm [Result] Initial period 1 hour 2 hours 3 hours 4 hours Example (Å / min) 1000 950 950 950 950 Comparative example (Å / min) 1000 950 875 800 720 As can be seen from these results, the apparatus of this example performs film formation more stably than the conventional apparatus, and forms a uniform protective film. It turns out that it exerts an excellent effect.

In the above-mentioned embodiment, the one having a mechanism for naturally dropping the used deposition preventive plate from the rail and collecting it is shown, but in addition to this, a collecting mechanism as shown in FIG. 5 may be used. it can. In FIG. 5, reference numeral 21 is a deposition preventive plate having a hole 21a formed in the center thereof, and 22a and 22b are rails, from a holder (not shown) holding an unused deposition preventive plate to a used deposition preventive plate recovery holder 23. Extends to a position facing the opening.

Reference numeral 24 denotes a shaft which projects and retracts beyond the rails 22a and 22b, and has an opening and closing claw 25a at its tip.
25b are provided. When the claws 25a and 25b are in the closed state, the diameter of the tip portion is equal to the diameter of the hole 21 of the deposition preventing plate 21.
The diameter is smaller than the diameter of a, and conversely, it is larger than that in the open state. In the apparatus using this recovery mechanism, the shaft 24 is inserted into the deposition-inhibitory plate 21 that has been sent to the opening position of the used deposition-inhibition plate recovery holder 23, and the claw portion 2
5a and 25b are opened and the attachment plate 21 is hooked. Then, by retracting the shaft 24, the deposition-inhibitory plate 21 is disengaged from the rails 22a and 22b and is forcibly drawn into the deposition-inhibition plate recovery holder 23.

[0030]

[Effect] According to the present invention, it is not necessary to clean the microwave transmission window during the film forming operation, and the film forming operation can be continuously and efficiently performed.

[Brief description of drawings]

FIG. 1 is a plan view of a main part of an ECR microwave plasma CVD apparatus.

FIG. 2 is a front view of the main part of the apparatus viewed from the cooling can roll side.

FIG. 3 is a plan view of the main parts of the device showing a situation in which the attachment-preventing plate is being replaced.

FIG. 4 is a plan view of an essential part of the device showing a situation in which the replacement of the deposition preventive plate is completed.

FIG. 5 is a plan view of an essential part of an apparatus showing another embodiment of the deposition prevention plate recovery mechanism.

FIG. 6 is a schematic diagram of a conventional ECR microwave plasma CVD apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Vacuum tank 2 Plasma reaction tube 2a Microwave transmission window 4 Adhesion prevention plate 5 Adhesion plate holder (adhesion plate holding means) 9 Push rods (adhesion plate sending means) 12a, 12b Rails 13 Adhesion plate collection pocket Plated plate collecting means) 14a Convex portion (locking mechanism) 14b Recessed portion (locking mechanism)

Claims (5)

[Claims] 1. An apparatus for forming a thin film by a plasma CVD method on a support located at a position facing a plasma reaction tube, the position facing a vacuum chamber and a support disposed in the vacuum chamber. And a plasma reaction tube provided with a microwave transmission window on one end side thereof, a reaction gas supply means for supplying a reaction gas into the plasma reaction tube, and a microwave reaction tube inside the plasma reaction tube through the microwave transmission window. A microwave oscillating means for supplying a microwave, an anti-adhesion plate that is provided in the plasma reaction tube so as to be exchangeable and faces the microwave transmission window, and a used anti-adhesion plate is an unused one. A thin film forming apparatus, comprising: a deposition-preventing plate replacement means for replacement. 2. An apparatus for forming a thin film by a plasma CVD method on a support located at a position facing a plasma reaction tube, the position facing a vacuum chamber and a support provided in the vacuum chamber. And a plasma reaction tube provided with a microwave transmission window on one end side thereof, a reaction gas supply means for supplying a reaction gas into the plasma reaction tube, and a microwave reaction tube inside the plasma reaction tube through the microwave transmission window. A microwave oscillating means for supplying a microwave, an anti-adhesion plate that is provided in the plasma reaction tube so as to be exchangeable and faces the microwave transmission window, and an anti-adhesion plate that holds a predetermined number of the anti-adhesion plates. A holding means, an adhesion-preventing plate sending-out means for receiving an unused adhesion-preventing plate from the holding means, and sending it out so as to face the microwave transmission window, and a used protection plate Thin film forming apparatus characterized by comprising; and a deposition preventing plate recovery means. 3. The adhesion-preventing plate holding means and the adhesion-preventing plate collecting means are provided at positions sandwiching a microwave transmission window, and are bridged between the adhesion-preventing plate holding means and the adhesion-preventing plate collecting means. The thin film forming apparatus according to claim 2, wherein the deposition preventing plate is sent out from the deposition preventing plate holding means side to the deposition preventing plate collecting means side by being guided by the formed rail. 4. The rail is provided with a hooking portion for stopping an unused adhesion-preventing plate sent out by the adhesion-preventing plate sending means, facing the microwave transmission window. The thin film forming apparatus according to claim 3. 5. A hole is formed in the center of the adhesion-preventing plate, and a tip portion of the adhesion-preventing plate collecting means has a diameter larger than the diameter of the hole formed in the adhesion-preventing plate, and A shaft is provided that protrudes and retracts beyond the rail position, and after inserting the tip of the shaft into the hole of the used deposition prevention plate at the recovery position,
The thin film forming apparatus according to claim 3 or 4, wherein the thin film forming apparatus is configured to be opened and expanded, and a used deposition preventing plate is forcibly separated from the rail and collected.