JP3100888B2 - Vacuum deposition equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an improvement in a vacuum evaporation apparatus.

[0002]

2. Description of the Related Art A vacuum deposition apparatus of this type ionizes a film-forming raw material gas by thermal electrons in a vacuum, accelerates ionized vapor deposition material molecules in the direction of a substrate by a negative voltage, and processes the material to be processed held on the substrate. An evaporation film is formed on an object.

[0003] In this vapor deposition process, when the vapor deposition material is an insulator, the substrate is covered with the vapor deposition film, so that current does not gradually flow through the substrate, and the film forming speed is reduced.
According to the measurement result, even if the initial current value was 4 mA on the substrate having a diameter of 250 mm, the current value after 30 minutes became 2 mA or less, and almost no current finally flowed. Has almost stopped growing. For this reason, in order to prepare for the next processing, the work of peeling the deposited film from the surface of the substrate is indispensable.

At the time of such a stripping operation, an inner cover, a cathode, and an anode provided inside the vacuum chamber are disassembled, and an operation of removing a deposited film adhered thereto is also performed. In this case, since the deposited film adheres well and cannot be easily removed, it is necessary to remove (clean) it by 4 to 5 times.
This was time consuming and this was a significant production time loss.

Although a DC negative voltage is applied to the substrate, when the workpiece is an insulator, it is difficult to control the acceleration of the ionized vapor deposition material molecules.
It was difficult to perform uniform deposition over an area of [mm] or more. If a high-frequency power supply is used instead of a DC power supply and a high-frequency voltage is applied to the substrate, the deposition area of the insulating film becomes larger than when the DC power supply is used.
The power supply device is expensive because it is about twice as high.

[0006]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to suppress a decrease in the current of a substrate during the process of depositing an insulating film, to increase the deposition area of an insulator sample when a DC voltage is applied to the substrate, and to further reduce the vacuum. The purpose is to make it easy to clean the inner cover, cathode and anode inside the tank.

[0007]

According to the above object, the present invention applies a voltage to a cathode and an anode in a vacuum chamber to emit thermoelectrons from the cathode toward the anode. In a vacuum deposition apparatus that forms a deposition film on a workpiece held by a substrate by ionizing a film source gas and accelerating ionized deposition material molecules in the direction of the substrate by a negative voltage applied to the substrate, The area is larger than the area of the film forming surface of the workpiece, a shielding plate is provided on the cathode / anode facing side of the substrate, and an opening having a size corresponding to the film forming area of the workpiece is formed on this shielding plate. At the same time, a control electrode made of conductive mesh is placed at a predetermined distance from the substrate on the side of the shield plate facing the cathode and anode, and this control electrode is set to the same negative potential as the substrate Furthermore, the inner cover is detachably attached to the vacuum tank, the cathode / anode socket and the receiver inside the vacuum tank, and the cathode and the anode are detachably attached to the cathode / anode holder. ing.

[0008] At the time of vapor deposition, the shielding plate is
Since the ionized vapor deposition material molecules are blocked on the side facing the anode, the ionized vapor deposition material molecules do not adhere to the substrate at the blocked portion, and thus the substrate current does not decrease. In addition, there is a control electrode on the side of the shield plate facing the cathode and anode, which uniformly diffuses ionized deposition material molecules, so that even if the workpiece is an insulator, a uniform electric field can be obtained over a large range. Thus, the insulating film can be deposited over a large area.

Further, since the inner cover can be easily taken out from the inside of the vacuum chamber and the cathode and anode can be easily attached to and detached from the holder, they can be replaced by a spare one in a continuous vapor deposition process. Can be continuously performed without any loss time.

[0010]

1 to 7 show a vacuum deposition apparatus 1 according to the present invention.
Is shown. The vacuum evaporation apparatus 1 includes a cathode 3, an anode 4, an inner cover 5,
A substrate 6 and a control electrode 7 are provided. Vacuum chamber 2
Is configured so that it can be hermetically closed by the bottom plate 8, the cylindrical body 9, and the lid plate 10. The lid plate 10 can be opened and closed vertically with respect to the upper surface of the cylindrical body 9 by an opening and closing mechanism.

The cathode 3 and the anode 4 are connected to a vacuum chamber 2
Are slightly opposed to each other, are housed in an insulator socket receiver 13 by insulator sockets 11 and 12, and are electrically connected to terminals 14 and 15 by nuts 16. It is detachably attached to the socket receiver 13. The socket receiver 13
And terminals 14 and 15 are connected to a terminal plate 19 attached to the bottom plate 8 by two supports 17 and pipes 18.
It is fixed to.

The inner cover 5 is of a top opening type, is housed in the vacuum chamber 2 and has a support 20 on the substrate 8.
On the socket receiver 13 and the socket receiver 1 against the socket receiver 13.
3 is detachably attached to the socket receiver 13 by upper and lower presser nuts 21 at a hole portion substantially equal to that of the socket receiver 3. Note that a film forming material gas 22 such as a hydrocarbon gas or an organic metal gas (Mo gas) is supplied to the inside of the vacuum chamber 2 from a gas discharge port 24 substantially at the center of the inner cover 5 via an introduction valve 23. Radiation flows in by the diffusion plate 40.

The substrate 6 is attached to the lower end of the rotary shaft 26 inside the vacuum chamber 2 and holds, for example, four workpieces 28 in a downward direction at the holder 27. . The rotating shaft 26 also serves as a cooling water circulation path, is rotatably mounted on a bearing 29 mounted on the cover plate 10, and is driven by a drive motor 30 and a timing belt pulley 31 during a vapor deposition process. It is mounted so that it can rotate at speed. In addition, a vacuum pump 32 is attached to the exhaust port 25 with a filter.

The area of the substrate 6 is larger than the total film forming area of the four workpieces 28 and has a shielding plate 33 on the side facing the cathode 3 and the anode 4.
The shielding plate 33 is substantially the same size as the substrate 6, is attached in parallel with the substrate 8 at an appropriate interval, and has an opening slightly larger than the film forming area of the four workpieces 28. 34.

The control electrode 7 is made of a conductive mesh, is located on the side facing the cathode 3 and the anode 4 with respect to the shielding plate 33, and is arranged at a predetermined distance from the substrate 6. Have been. The size of this mesh corresponds to the maximum value of the deposition area by DC power supply,
Set it to 7 mm or less. In addition, a shielding plate 38 having an opening 39 is attached to the control electrode 7 on the side facing the cathode 3 and the anode 4 as necessary.

The cathode 3 is connected to an AC power supply 35.
The anode 4 is connected to the positive side of a DC power supply 36, and the substrate 6 and the control electrode 7 are both connected to the negative side of a common DC power supply 37.

At the time of vapor deposition, the four workpieces 28 are
With the cover 7 fixed to the substrate 6 with 7 and the cover plate 10 applied to the upper surface of the cylindrical body 9, the inside of the vacuum chamber 2 is brought into a state of an appropriate degree of vacuum by the vacuum pump 32. In this state, a hydrocarbon (CH ₄ ) -based source gas 22 is supplied from the introduction valve 23 into the vacuum chamber 2 to form, for example, a diamond-like carbon film. Cathode 3 and anode 4
Is applied, a thermoelectron is emitted from the cathode 3 toward the anode 4. These thermoelectrons ionize the film forming raw material gas 22 inside the vacuum chamber 2 to be in a plasma state. The substrate 6 and the control electrode 7 accelerate the ionized deposition substance molecules (ionized hydrocarbon molecules) in the direction of the substrate 6 by the negative potential, and form a diamond-like carbon film on the surface of the workpiece 28.

In this vapor deposition process, the ionized hydrocarbon molecules are uniformly diffused by the control electrode 7, and therefore collide with a large area against the workpiece 28, which is a DC potential insulator. In addition, the ionized hydrocarbon molecules almost collide with the vapor deposition surface of the workpiece 28 through the opening 34 of the shielding plate 33, and do not go around the outer peripheral surface of the electrode 6 and the back surface of the shielding plate 33. As a result, adhesion of the ionized hydrocarbon molecules to the substrate 6 is reduced, and a decrease in current due to this can be prevented. Similarly, since the control electrode 7 also has the shielding plate 38, the opening 3 of the shielding plate 38 is formed.
The formation of an insulating vapor-deposited film in portions other than those corresponding to No. 9 is suppressed. Therefore, a stable film can be formed at a constant film forming rate over a long time.

When the vapor deposition is completed, the cover plate 10 is opened, and the workpiece 28 is removed from the holder 27 of the substrate 6. In this state, if necessary, the cathode 3 and the anode 4
And the inside of the inner cover 5 is cleaned (removal of the deposited film). During this cleaning, the cathode 3 and the anode 4 can be easily removed from the socket receiver 13 by loosening the nut 16. Further, by loosening the presser nut 21, the inner cover 5 is separated from the socket receiver 13, so that the inner cover 5 can be taken out of the vacuum chamber 2 and cleaned. Therefore, if the spare inner cover 5, the cathode 3, and the anode 4 are attached during the cleaning of the inner cover 5, the cathode 3, and the anode 4 after the removal, the used inner cover 5, the cathode 3, and the anode 4 are cleaned during the cleaning. In addition, the preliminary operation allows the vapor deposition operation to be continued.

[0020]

According to the present invention, the following specific effects can be obtained. During deposition, the shielding plate blocks the ionized vapor deposition material molecules on the cathode / anode facing side of the substrate, so that the ionized vapor deposition material molecules do not adhere to the substrate at the cut-off portion, thereby reducing the current. Disappears. Also,
There is a control electrode on the cathode / anode facing side of the shielding plate, which uniformly diffuses the ionized deposition material molecules, so that even if the workpiece is an insulator, a uniform electric field can be obtained over a large range. An insulating film can be deposited over a large area. Furthermore, since the inner cover can be easily removed from the inside of the vacuum chamber and the cathode and anode can be easily attached to and detached from the holder, replacing them with spare ones in the continuous evaporation process can reduce the evaporation time. It can be done continuously without any

[Brief description of the drawings]

FIG. 1 is a sectional view of a vacuum evaporation apparatus.

FIG. 2 is a front view of an anode and a supporting portion of the anode.

FIG. 3 is a cross-sectional view of a part of a supporting portion of a cathode and an anode.

FIG. 4 is a plan view of a substrate and a shielding plate.

FIG. 5 is a sectional view of a substrate and a shielding plate.

FIG. 6 is a plan view of a control electrode and a shielding plate.

FIG. 7 is a sectional view of a control electrode and a shielding plate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Vacuum vapor deposition apparatus 21 Holding nut 2 Vacuum tank 22 Film forming material gas 3 Cathode 23 Introducing valve 4 Anode 24 Gas discharge port 5 Inner cover 25 Filter outlet 6 Substrate 26 Rotating shaft 7 Control electrode 27 Holder 8 Bottom plate 28 Cover Workpiece 9 Cylindrical body 29 Bearing 10 Cover plate 30 Drive motor 11 Socket 31 Timing belt pulley 12 Socket 32 Vacuum pump 13 Socket receiver 33 Shielding plate 14 Terminal 34 Opening 15 Terminal 35 AC power supply 16 Nut 36 DC power supply 17 Support 37 DC Power supply 18 Pipe 38 Shielding plate 19 Terminal plate 39 Opening 20 Support 40 Diffusion plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C23C 14/00-14/58

Claims (1)

(57) [Claims] 1. A voltage is applied to a cathode and an anode in a vacuum chamber to emit thermoelectrons from the cathode to the anode, and the thermoelectrons ionize a film-forming material gas in the vacuum chamber to form an ionized vapor deposition material. In a vacuum deposition apparatus that forms a vapor deposition film on a workpiece held on a substrate by accelerating molecules in the direction of the substrate by a negative voltage applied to the substrate, the area of the substrate is reduced by the area of the film formation surface of the workpiece. Larger than the area,
A shield plate is provided on the cathode / anode facing side of the substrate, and an opening having a size corresponding to the film formation area of the workpiece is formed on the shielding plate. A control electrode made of a conductive mesh is arranged at a predetermined interval, the control electrode is set to the same negative potential as the substrate, and an inner cover is provided inside the vacuum chamber with respect to the vacuum chamber and the cathode / anode holder. And a cathode and an anode are detachably attached to a cathode / anode socket receiver.