JP4173759B2 - Arc evaporation film deposition system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an arc evaporation type film forming apparatus including an arc evaporation source.
[0002]
[Prior art]
The arc evaporation type film forming apparatus can form a film made of a material constituting the target cathode of the arc evaporation source by generating arc discharge by the arc evaporation source.
[0003]
FIG. 2 is a diagram showing a structure of an arc evaporation source 60 used in a conventional arc evaporation film forming apparatus (see, for example, Utility Model Registration Document 1 and Patent Document 2). FIG. 2 schematically shows the connection between the arc evaporation source 60 and the power source 64.
[0004]
The arc evaporation source 60 is disposed in the vacuum chamber and is connected to a DC power source 64 disposed outside the vacuum chamber. The arc evaporation source 60 is supplied with electric power from the DC power source 64 and forms an arc discharge in the vacuum chamber.
[0005]
As a result of the arc discharge being formed, the material constituting the target cathode 62 evaporates, and a film is formed on a base material (not shown) arranged to face the arc evaporation source 60 in the vacuum chamber.
[0006]
As shown in FIG. 2, the conventional arc evaporation source 60 is provided with a trigger electrode 65. That is, in the conventional arc evaporation source 60, the trigger electrode 65 is moved away from the target cathode 62 in the vertical direction from the state in which the tip of the trigger electrode 65 is in contact with the surface of the target cathode 62, and arc discharge is started. I am doing so.
[0007]
The arc evaporation film forming apparatus including the arc evaporation source 60 and the arc evaporation source 60 is also provided with a mechanism for driving the trigger electrode 65 in the vertical direction with respect to the target cathode 62.
[0008]
In addition, the trigger electrode 65 is retracted from the vicinity of the evaporation source 60 once discharge is started, so that film formation by the evaporation source 60 after starting arc discharge is not hindered. 0009
[Utility model registration document 1]
Japanese Utility Model Publication No. 3-11226 (FIG. 1).
[Patent Document 2]
Japanese Patent No. 3287163 (FIG. 1).
[0010]
[Problems to be solved by the invention]
As described above, in the conventional arc evaporation source 60, the trigger electrode 65 is provided, and the trigger electrode 65 and a mechanism for supporting and driving the trigger electrode 65 are connected to the arc evaporation source 60 or the vicinity thereof. Had to be established.
[0011]
For this reason, the arc evaporation source 60 could not have a simple structure. Further, when the discharge is started by the trigger electrode 65, the substance constituting the trigger electrode 65 is mixed in the film to be formed, and the film quality is lowered.
[0012]
Therefore, an object of the present invention is to provide an arc evaporation type film forming apparatus capable of easily starting discharge and solving the above problems by removing a trigger electrode from an arc evaporation source.
[0013]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a target cathode, a shield plate disposed so as to surround the target cathode in the vicinity of the side of the tip of the target cathode, and a magnet disposed on the base end side with respect to the target cathode. An arc evaporation source, a vacuum chamber, and a power supply means for supplying power to the arc evaporation source, and a predetermined DC power is supplied to the arc evaporation source by the power supply means to cause arc discharge in the vacuum chamber. The arc discharge is formed on the base material disposed in the vacuum chamber by forming the arc discharge and stabilizing the arc discharge by the shield plate and the magnet. A power supply means for applying a predetermined high voltage between the target cathode and the shield plate. To generate a spark discharge by pressure, the is configured to form the arc discharge a spark discharge after generating, after generating the spark discharge by applying a high voltage by the power supply unit, the high voltage A switching means for switching to stop the application is provided.
[0014]
According to the arc evaporation type film forming apparatus of the present invention, a spark discharge is generated between the target cathode and the shield plate, and the arc discharge is generated by generating the spark discharge.
[0015]
Therefore, according to the arc evaporation type film forming apparatus of the present invention, arc discharge can be generated without providing a trigger electrode in the arc evaporation source. Thus, by omitting the trigger electrode, the arc evaporation source can have a simple structure, and contamination of the film to be formed can be prevented and deterioration of the film quality can be prevented.
[0016]
Further, the power supply means includes a high voltage generator for supplying a high voltage for generating the spark discharge and a direct current power source for supplying power for forming the arc discharge,
In the first circuit for connecting the DC power supply, the target cathode and the vacuum chamber are connected such that the negative terminal is connected to the target cathode and the positive terminal is connected to the vacuum chamber. Intervening,
The high-voltage generator can be interposed in a second circuit that connects the target cathode and the shield plate (Claim 2).
[0017]
According to the present invention, the high voltage for generating the spark discharge is supplied by the high voltage generator, and the electric power for forming the arc discharge is supplied by the DC power source. Thereby, since the high voltage generator and the DC power supply can be individually controlled, it is easy to control the power supply means related to the generation of the spark discharge.
[0018]
Further, for an arc evaporation type film forming apparatus in which the power supply means includes a high voltage generator and a DC power supply (Claim 2), current detection for detecting the occurrence of the arc discharge by detecting conduction of a predetermined current Further providing means,
A switching means is provided in a portion excluding a portion overlapping the first circuit in the second circuit,
The switching means is maintained in a state where the electric resistance of the second circuit is reduced until the arc discharge occurs, and when the occurrence of the arc discharge is detected by the current detection means, the electric current of the second circuit is detected. The resistance can be switched so as to increase (claim 3).
[0019]
According to the present invention, when the occurrence of arc discharge is detected, the switching means switches the second circuit to a state where the electrical resistance is increased. As a result, the shield plate is in an electrically floating state from the vacuum chamber, and arc discharge is formed between the target cathode and the inner surface of the vacuum chamber.
[0020]
The switching means can be an on / off switch that switches between conduction and non-conduction between both ends. Thereby, the switching means for switching the connection between the shield plate and the power supply means can be simplified.
[0021]
Further, when the occurrence of arc discharge is detected by the current detection means, the operation of the high voltage generator can be stopped (Claim 5). Thereby, after generating arc discharge, a high voltage generator can be stopped and inefficient operation | movement of an apparatus can be prevented.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a diagram showing an outline of the configuration of an arc evaporation type film forming apparatus 1 according to an embodiment of the present invention. FIG. 1 shows a schematic cross-sectional view of the arc evaporation source 6 of the arc evaporation film forming apparatus 1 and a schematic relationship between the arc evaporation source 6, the power supply means 10, and the vacuum chamber 25. Yes.
[0023]
The arc evaporation type film forming apparatus 1 includes an arc evaporation source 6, a power supply means 10, and a vacuum chamber 25. The arc evaporation source 6 includes a target cathode 7, a shield plate 8, and a magnet 9.
[0024]
The target cathode 7 is disposed at the tip of the arc evaporation source 6. The shield plate 8 has a hollow disk shape, and is disposed in the vicinity of the side of the tip of the target cathode 7 so as to surround the target cathode 7. The magnet 9 is disposed on the base end side with respect to the target cathode 7.
[0025]
The state of arc discharge in the vicinity of the surface of the target cathode 7 can be stabilized by the magnet 9 and the shield plate 8.
[0026]
The arc evaporation source 6 is supplied with electric power from the electric power supply means 10. The power supply means 10 includes a DC power supply 11 and a high voltage generator 12. The DC power source 11 supplies DC power for forming arc discharge to the arc evaporation source 6.
[0027]
The DC power source 11 includes a negative electrode side terminal and a positive electrode side terminal, and has a voltage value of about 10 to 100 V (volt) as DC power, and a power value of about 10 to 500 A (ampere). Output.
[0028]
The DC power source 11 is interposed in a first circuit that connects the target cathode 7 and the vacuum chamber 25. The first circuit is a circuit for connecting the target cathode 7 and the vacuum chamber 25 through output terminals 12a and 12b of the high voltage generator 12 and a DC power supply 11 which will be described later.
[0029]
The DC power supply 11 has a negative terminal connected to the target cathode 7 side and a positive terminal connected to the vacuum chamber 25 side. The vacuum chamber 25 is set to the ground potential, and the positive terminal of the DC power supply 11 is set to the ground potential.
[0030]
The positive terminal of the DC power supply 11 is also connected to the shield plate 8 via the changeover switch 13. The structural member of the vacuum chamber 25 is made of a conductive material and constitutes a part of a circuit that operates the arc evaporation source 6. Further, when the arc evaporation source 6 is disposed in the vacuum chamber 25, the target cathode 7 is electrically insulated from the structural members of the vacuum chamber 25.
[0031]
The high voltage generator 12 supplies a high voltage for generating a spark discharge to the arc evaporation source 6. The spark discharge is an initial discharge for forming an arc discharge after this discharge.
[0032]
The high voltage generator 12 outputs a high voltage of about several thousand to several tens of thousands of volts (V). The high voltage formed by the high voltage generator 12 is output from the two output terminals 12a and 12b.
[0033]
The high voltage generator 12 is interposed in a second circuit that connects the target cathode 7 and the shield plate 8. The second circuit is a circuit for connecting the target cathode 7 and the shield plate 8 through the output terminals 12a and 12b of the high voltage generator 12, the DC power source 11, and an on / off switch 13 described later.
[0034]
One output terminal 12 a of the high voltage generator 12 is connected to the target cathode 7. The other output terminal 12 b of the high voltage generator 12 is connected to the negative terminal of the DC power supply 11.
[0035]
The negative terminal of the DC power supply 11 is connected to the target cathode 7 via the output terminal of the high voltage generator 12. The other terminal 12 b of the high voltage generator 12 is connected to the on / off switch 13 via the DC power supply 11 and further connected to the shield plate 8.
[0036]
As the high-voltage generator 12, it is preferable to use a device that outputs a high voltage using AC power. This is because, when the high voltage generator 12 is an apparatus that outputs AC power, the operation of the high voltage generator 12 can be easily controlled when supplying a high voltage to the arc evaporation source 6. In particular, it is more preferable to use a device that outputs a high frequency high voltage.
[0037]
In addition, a current sensor 14 is provided in a circuit that connects the power supply means 10 to the arc evaporation source 6 and the vacuum chamber 25. This current sensor 14 detects the current supplied from the power supply means 10 to the arc evaporation source 6.
[0038]
When this current sensor 14 detects a constant current and detects that arc discharge has been formed, the high voltage generator 12 is controlled to stop its operation, and the changeover switch 13 is controlled to be turned off. The The current sensor 14 corresponds to current detection means for detecting the occurrence of arc discharge.
[0039]
The on / off switch 13 is interposed in a portion of the second circuit that connects the target cathode 7 and the shield plate 8 except for a portion that overlaps the first circuit.
[0040]
In the circuit shown in FIG. 1, when the changeover switch 13 is closed and turned on, the shield plate 8 and the vacuum chamber 25 are short-circuited by the changeover switch 13, and the shield plate 8 is set to the ground potential.
[0041]
On the other hand, when the changeover switch 13 is opened and turned off, the target cathode 7 and the shield plate 8 are opened, the connection to the high voltage generator 12 is disconnected, and a high voltage is applied between the target cathode 7 and the shield plate 8. Not supplied.
[0042]
Further, when the changeover switch 13 is turned off, the shield plate 8 is in an electrically floating state from the vacuum chamber 25 and takes a potential different from that of the grounded vacuum chamber 25.
[0043]
The change-over switch 13 is provided for switching the second circuit between a state where the electric resistance is small and a state where the electric resistance is large, and corresponds to a switching means.
[0044]
1 is electrically insulated from the vacuum chamber 25. The circuit connecting the changeover switch 13 and the shield plate 8 shown in FIG.
[0045]
Further, the arc evaporation type film forming apparatus 1 includes a controller (not shown) for controlling the operation thereof. The current value detected by the current sensor 14 is detected by this controller.
[0046]
Further, the controller is configured to stop the operation of the high voltage generator 12 and control the on / off of the changeover switch 13 based on the detection of the current by the current sensor 14.
[0047]
The vacuum chamber 25 is evacuated by an evacuation unit (not shown) with the inside thereof being closed from the outside space, and a vacuum atmosphere required for executing the film forming process by operating the arc evaporation source 6 is obtained. .
[0048]
The arc evaporation type film forming apparatus supplies a required process gas into the vacuum chamber 25 so that the inside of the vacuum chamber 25 can be adjusted to a required pressure by the gas. As this process gas, an inert gas such as an argon (Ar) gas is supplied.
[0049]
The film forming apparatus 1 is configured such that a base material holder (not shown) is disposed in the vacuum chamber 25. The base material to be deposited is held by the base material holder so as to face the arc evaporation source 6.
[0050]
An example of operating the film forming apparatus 1 described above will be described. The arc evaporation source 6 is disposed in the vacuum chamber 25 such that the target cathode 7 and the shield plate 8 are located in the vacuum chamber 25 as shown in FIG.
[0051]
Then, a base material (not shown) is disposed in the vacuum chamber 25 and the vacuum chamber 25 is closed. Then, while evacuating the vacuum chamber 25, argon gas is supplied as an inert gas to adjust to a required gas pressure.
[0052]
In supplying argon gas into the vacuum chamber 25, in the process of generating spark discharge in the arc evaporation source 6 described below, the gas pressure is adjusted slightly higher than in the process of forming a film by forming arc discharge. preferable.
[0053]
Next, when the power supply unit 10 is operated, a DC voltage output from the DC power source 11 and a high voltage output from the high voltage generator 12 are applied to the arc evaporation source 6.
[0054]
The arc evaporation source 6 generates a spark discharge by the high voltage supplied from the high voltage generator 12. The arc evaporation source 6 generates arc discharge after generating this spark discharge.
[0055]
Here, when the arc evaporation source 6 generates arc discharge, the current sensor 14 detects conduction of current accompanying the occurrence of arc discharge. When the occurrence of arc discharge is detected, the high voltage generator 12 is controlled to stop its operation, and the changeover switch 13 is controlled to be turned off.
[0056]
When the changeover switch 13 is turned off, the shield plate 8 is brought into an electrically floating state from the vacuum chamber 25. Thereby, arc discharge is formed between the target cathode 7 and the inner surface of the vacuum chamber 25.
[0057]
Then, arc discharge is formed by the arc evaporation source 6, whereby the raw material of the film constituting the target cathode 7 is ionized. Then, the ionized film material is discharged from the target cathode 7 toward the space in the vacuum chamber 25. Thereby, a film is formed on the substrate held in the vacuum chamber 25.
[0058]
As described above, according to the arc evaporation type film forming apparatus 1, a high voltage is applied between the target cathode 7 and the shield plate 8 of the arc evaporation source 6 by the power supply means 10 to generate a spark discharge. Is generated.
[0059]
Thereby, it is not necessary to provide a trigger electrode in the arc evaporation source 6. Thereby, the structure of the arc evaporation source 6 can be simplified, and maintenance for exchanging the target cathode 7 of the arc evaporation source 6 can be facilitated. In addition, since discharge by the trigger electrode is not used, it is possible to prevent impurities from being mixed into the film and to prevent deterioration of the film quality.
[0060]
In the above description based on FIG. 1, the DC power supply 11 and the high voltage generator 12 are connected in series, and the first circuit in which the DC power supply 11 is interposed and the high voltage generator 12 are interposed. The example which provided so that a part of 2nd circuit might overlap was given.
[0061]
In carrying out the present invention, a first circuit and a second circuit are provided independently of each other, a DC power source is interposed in the first circuit, and a high voltage generator is interposed in the second circuit. You can also
[0062]
Moreover, in the above description, the example which comprises the power supply means 10 by providing two types of power supplies, DC power supply 11 and the high voltage generator 12, was given. Thus, it is preferable to provide two types of power supplies, because the operation can be controlled for each power supply, so that it is easy to control the operation after the spark discharge is generated.
[0063]
On the other hand, the power supply means for operating the arc evaporation source 6 can be configured by a single power source. That is, it is possible to supply a high voltage output for generating a spark discharge with a single power source and a DC power for forming an arc discharge for film formation.
[0064]
In the above description, the changeover switch 13 is provided as a changeover means, and when the occurrence of arc discharge is detected, the changeover switch 13 is turned off to disconnect the electrical connection between the vacuum chamber 25 and the shield plate 8. An example has been given in which the electric resistance of the second circuit is increased and the electric potential of the shield plate 8 is made different from the electric potential of the vacuum chamber 25.
[0065]
As another example of the changeover means, the changeover switch 13 and a resistor (not shown) connected in parallel to the changeover switch 13 can be used. If the switching means is configured in this way, when the switch 13 is turned off, the resistance of the circuit connecting the target cathode 7 and the shield plate 8 is switched to a state in which the resistance connected in parallel increases the shield. The potential of the plate 8 is different from the potential of the vacuum chamber 25.
[0066]
【The invention's effect】
According to the present invention, as described above, arc discharge is generated by applying a high voltage between the target cathode of the arc evaporation source and the shield plate to generate spark discharge. Thereby, the trigger electrode can be omitted from the arc evaporation source.
[0067]
Thereby, the structure of the arc evaporation source can be simplified. In addition, deterioration of the film quality of the formed film can be prevented.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of an arc evaporation type film forming apparatus.
FIG. 2 is a diagram showing a conventional arc evaporation source.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Arc evaporation type film-forming apparatus 6 Arc evaporation source 7 Target cathode 8 Shield plate 9 Magnet 10 Power supply means 11 DC power supply 12 High voltage generator 12a One output terminal 12b The other output terminal 13 Changeover switch 14 Current sensor 25 Vacuum chamber 60 (conventional) arc evaporation source 62 target cathode 64 DC power supply 65 trigger electrode

Claims (5)

An arc evaporation source comprising a target cathode, a shield plate disposed so as to surround the target cathode in the vicinity of the side of the tip of the target cathode, and a magnet disposed on the base end side with respect to the target cathode; a vacuum chamber; Power supply means for supplying power to the arc evaporation source,
A predetermined DC power is supplied to the arc evaporation source by the power supply means to form an arc discharge in a vacuum chamber, and the arc discharge is stabilized by the shield plate and the magnet. An arc evaporation type film forming apparatus for forming a film on a substrate disposed in the vacuum chamber by forming
A spark discharge is generated by applying a predetermined high voltage between the target cathode and the shield plate by the power supply means, and the arc discharge is formed after the spark discharge is generated .
An arc evaporation type film forming apparatus, comprising: switching means for switching so as to stop the application of a high voltage after generating a spark discharge by the application of a high voltage by the power supply means . The power supply means includes a high voltage generator for supplying a high voltage for generating the spark discharge and a DC power source for supplying DC power for forming the arc discharge,
The DC power supply is configured in a first circuit that connects the target cathode and the vacuum chamber such that a negative terminal is connected to the target cathode and a positive terminal is connected to the vacuum chamber. Is intervening,
The arc evaporation film forming apparatus according to claim 1, wherein the high voltage generator is interposed in a second circuit that connects the target cathode and the shield plate. Current detection means for detecting the occurrence of the arc discharge by detecting conduction of a predetermined current,
The switching means is provided in a portion of the second circuit excluding a portion overlapping with the first circuit,
The switching means maintains the electric resistance of the second circuit at a low level until the arc discharge occurs, and the electric current of the second circuit is detected when the occurrence of the arc discharge is detected by the current detection means. 3. The arc evaporation type film forming apparatus according to claim 2, wherein the resistance is switched so as to increase the resistance. 4. The arc evaporation type film forming apparatus according to claim 3, wherein the switching means is an on / off switching switch for switching between conduction and non-conduction between both ends. 5. The arc evaporation type film forming apparatus according to claim 3, wherein when the occurrence of arc discharge is detected by the current detection means, the operation of the high voltage generator is stopped. 6.

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