JPH0570949A - Evaporation rate detector of arc ion plating device - Google Patents

Abstract

PURPOSE:To easily and surely detect a change in the evaporation rate of a target material by connecting a detecting electrode to a DC power source in such a manner that the electrode has a more negative potential than cathode and detecting the current flowing in the detecting electrode by an electrode detector. CONSTITUTION:The target 14 is mounted on the cathode 12. Arc ion plating is executed by generating an arc discharge between an anode 11 and the target 14 within a vacuum vessel 10 and forming the film of the target on the surfaces of objects 16 for vapor deposition. The detecting electrode 18 is, thereupon, provided in front of the cathode 12. The detecting electrode 18 is so connected to the DC electrode 19 as to attain the more negative potential than the cathode 12. The current flowing in the detecting electrode 18 is detected by a current detector 20. The operating conditions of the arc ion plating device are corrected in this way.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an evaporation amount detecting device in an arc ion plating device.

[0002]

2. Description of the Related Art FIG. 2 shows an outline of a conventional arc ion plating apparatus. In FIG. 2, reference numeral 1 is a metal vacuum container, and a pair of an anode 2 and a cathode 3 are provided on the wall surface of the vacuum container 1.
And are installed. It is also possible to use the wall surface of the vacuum container as the anode. The anode 2 is electrically connected to the + side of the arc power source 4, and the cathode 3 is electrically connected to the-side thereof. Further, the cathode 3 is attached with an evaporation material generally made of metal or the like, that is, a target 5.

A rotary table 6 is rotatably provided on the bottom surface of the vacuum container 1, and the rotary table 6 is connected to a bias power source 7 so as to have a predetermined negative potential with respect to the vacuum container 1.
In this arc ion plating device, the deposition object 8 is now placed on the rotary table 6, the inside of the vacuum container 1 is evacuated to a predetermined vacuum degree by a vacuum device (not shown), and then attached to the anode 2 and the cathode 3. An arc discharge is generated between the targets 5. Then, the target 5 material evaporates and ionizes,
A film of the target material is formed on the surface of the object to be vapor-deposited 8. At this time, by introducing a predetermined amount of reaction gas (nitrogen gas, hydrocarbon gas, oxygen, etc.) into the metal container 1, a metal nitride, carbide, or oxide film can be formed.

[0004]

In this type of device, the arc current and the evaporation amount of the target material are generally in a proportional relationship. However, when the target thickness decreases due to the consumption of the target 5, the evaporation amount decreases for the same arc current, and if operating under the same operating conditions, the thickness of the film formed on the deposition object 8 decreases. There is a problem in operation management.

Therefore, conventionally, a test piece is put in periodically and the thickness of the film formed on the test piece is actually measured to deal with it. However, this is very complicated and the operation rate There is a problem of causing a decrease. In view of the above conventional problems, it is an object of the present invention to measure the ion current of a target material and to easily and surely detect a change in the evaporation amount.

[0006]

According to the present invention, a target 12 is attached to a cathode 12, and an anode 11 and a target are placed in a vacuum container 10.
In an arc ion plating device in which an arc discharge is generated between 14 to form a film of the target material on the surface of the deposition object 16, a detection electrode is provided in front of the cathode 12.
18 is provided, the detection electrode 18 is connected to a DC power source 19 so as to have a negative potential than the cathode 12, and a current detector 20 for detecting a current flowing through the detection electrode 18 is provided.

[0007]

Since the detection electrode 18 in front of the cathode 12 has a negative potential with respect to the cathode 12, an ionic current from the target material flows through the detection electrode 18. Since the ionization rate of this target material has a certain value depending on the metal material,
The amount of evaporation can be known by detecting the ion current with the current detector 20.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. In FIG. 1, 10 is a vacuum container made of metal, and a pair of anode 11 and cathode 12 are attached to the wall surface. The anode 11 is connected to the + side of the arc power source 13, the cathode 12 is connected to the-side thereof, and the cathode 12 is attached with the target 14.

Reference numeral 15 denotes a turntable, which is rotatably provided on the bottom surface side in the vacuum container 10.
Is placed. Reference numeral 17 denotes a bias power source, which keeps the rotary table 15 at a negative potential with respect to the vacuum container 10. Reference numeral 18 denotes a detection electrode, which is fixed in front of the cathode 12 and at a position where it does not interfere with the material 16 to be deposited. The detection electrode 18 is connected to the negative side of a DC power source 19 that is interposed between the detection electrode 18 and the vacuum container 10 and has a voltage of 20 to 50 V
A voltage of a negative potential is applied sufficiently more than the cathode 12 of a certain degree. A current detector 20 detects the current flowing through the detection electrode 18, and is interposed between the detection electrode 18 and the DC electrode 19.

As described above, by providing the independent dedicated detection electrode 18 and connecting the current detector 20 thereto, the target
The evaporation amount of 14 can be known accurately. That is, in the arc evaporation phenomenon, the target material is highly ionized. This ionization rate has a constant value depending on the metal material, and the evaporation amount can be known by measuring the ion current. Therefore, although appearing as a tendency of the current flowing in the bias power source 17, the amount, shape, and
It is greatly affected by the vacuum pressure, and it is difficult to accurately grasp the change in the evaporation amount.

However, if the detection electrode 18 is provided, the cathode
Since the potential is sufficiently negative with respect to 12, an ionic current flows while preventing the inflow of electrons to the detection electrode 18, so that the vacuum pressure and arc current during measurement are kept constant by detecting the current. As long as it is, the change in the evaporation amount of the target 14 can be accurately known without being affected by the deposition object 16. That is, the current detector 20 can obtain a signal proportional to the evaporation amount of the target material. Therefore, this current detector 20
It is possible to correct the operating conditions by using the signal of 1 for control.

As the correction method at this time, specifically, it is most desirable to correct the arc current. For example, if the ion current is reduced by 10% due to the reduction of the target thickness, the initial ion current, that is, the initial evaporation amount can be obtained by increasing the arc current by 10%. Can be reproduced. Note that this correction operation is performed when the degree of vacuum is sufficiently high (1 × 10 ^-4 Torr
It is more accurate if it is performed (about the following), and usually, it may be performed at the beginning of the coating cycle, but the vacuum degree may be occasionally increased during coating.

[0013]

According to the present invention, the cathode 12 and the target 14 are
Mounted, by generating an arc discharge between the anode 11 and the target 14 in the vacuum container 10, in the arc ion plating apparatus to form a film of the target material on the surface of the deposition object 16, the cathode 12 of Since the detection electrode 18 is provided on the front side, the detection electrode 18 is connected to the DC power source 19 so as to have a negative potential than the cathode 12, and the current detector 20 for detecting the current flowing through the detection electrode 18 is provided. By measuring the ion current of the target material, the change in the evaporation amount can be detected easily and reliably.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a conventional example.

[Explanation of symbols]

 10 Vacuum container 11 Anode 12 Cathode 14 Target 16 Deposition object 18 Detection electrode 19 DC power supply 20 Current detector

Claims (1)

[Claims] 1. A target (14) is attached to a cathode (12), an arc discharge is generated between an anode (11) and a target (14) in a vacuum container (10), and a target material (16) is deposited. In an arc ion plating device that forms a film of target material on the surface, a detection electrode (18) is provided in front of the cathode (12), and this detection electrode (18) is at a negative potential than the cathode (12). A vaporization amount detection device in an arc ion plating device, characterized in that a current detector (20) for detecting a current flowing through the detection electrode (18) is provided by being connected to a DC power source (19).