JPH076894A - Plasma measuring probe - Google Patents

Abstract

PURPOSE:To prevent deviation in measurement of a plasma condition from being caused due to an effective area or change or the like of an electrode part of a plasma measuring probe by suppressing plasma pollution in the electrode part of the plasma measuring probe. CONSTITUTION:In a plasma measuring probe 10 arranged in a plasma generator so as to measure a condition of plasma generated in the plasma generator, a shielding member 12 is provided to shield an electrode part 100b of the plasma measuring probe 10 from the plasma generated in the plasma generator, and when the condition of the plasma generated in the plasma generator is not measured by the plasma measuring probe 10, the electrode part 100b is shielded from the plasma generated in the plasma generator by the shielding member 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma measuring probe, and more particularly to a plasma measuring probe for measuring the state of plasma in a plasma generator.

[0002]

2. Description of the Related Art Conventionally, a plasma measuring probe has been known as an apparatus for measuring the state of plasma in a plasma generator.

FIG. 3 shows a conventional plasma measuring probe 1.
00 shows a method of measuring the state of the plasma generated in the plasma generator 102.

The plasma generator 102 includes a vacuum reaction chamber 1
04, and a pair of electrodes 106 and 108 that are arranged to face each other in the vacuum reaction chamber 104. And
The electrode portion 100b protruding from the main body portion 100a of the plasma measurement probe 100 is arranged so as to be exposed between the pair of electrodes 106 and 108, and the plasma state is measured.

In the above structure, when the vacuum reaction chamber 104 is depressurized and a voltage is applied to the pair of electrodes 106 and 108 to generate plasma in the vacuum reaction chamber 104, the state of the plasma is measured by the plasma measurement probe. It could be measured by 100.

[0006]

By the way, in the above-mentioned conventional plasma measurement probe, the electrode portion of the plasma measurement probe is always exposed in the vacuum reaction chamber. Therefore, the electrode portion of the plasma measurement probe will be left in the plasma for a long time even though the state of the plasma is not measured,
On the surface of the electrode part of the plasma measurement probe, there is a possibility that plasma contamination such as film formation and sputtering action may occur. When such plasma contamination occurs, it causes a change in the effective area of the electrode portion, which causes a deviation in the measurement of the plasma state, which makes it impossible to ensure reproducibility of measurement. There was a point.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to suppress plasma contamination in the electrode portion of the plasma measurement probe and to obtain the plasma measurement probe. An object of the present invention is to provide a plasma measurement probe that does not cause a deviation in measurement of the plasma state due to a change in the effective area of the electrode part.

[0008]

In order to achieve the above object, a plasma measuring probe according to the present invention is arranged in a plasma generator and is used for measuring the state of plasma generated in the plasma generator. In the plasma measurement probe, the electrode part of the plasma measurement probe is provided with a shielding member capable of shielding from the plasma generated in the plasma generation device, and the state of the plasma generated in the plasma generation device by the plasma measurement probe. Is measured, the electrode portion is shielded from the plasma generated in the plasma generator by the shielding member.

[0009]

When the state of the plasma generated in the plasma generator is not measured, the electrode part of the plasma measurement probe is shielded from the plasma generated in the plasma generator by the shield member.

Therefore, the state where the electrode portion of the plasma measurement probe is always exposed to the plasma can be eliminated, so that the generation of plasma contamination in the electrode portion of the plasma measurement probe is suppressed and the electrode portion of the plasma measurement probe is prevented. It is possible to prevent the deviation of the measurement of the plasma state due to the change of the effective area.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a plasma measuring probe according to the present invention will be described in detail below with reference to the drawings. It should be noted that configurations that are the same as or equivalent to the configurations shown in FIG. 3 are denoted by the same reference numerals, and detailed description of the configurations and actions thereof will be omitted.

FIG. 1 shows the structure of a plasma measuring probe according to an embodiment of the present invention. The plasma measuring probe 10 is movable in the axial direction of the main body 100a (the direction of the arrow in FIG. 1). It is configured to include a cylindrical shield cover 12 arranged and a shield cover movable device 14 for axially moving the shield cover 12.

That is, the shield cover 12 can be moved in the axial direction by driving the shield cover moving device 14 based on a shield cover moving signal generated in response to an operation of an operator (not shown). It is said that. In addition,
Ceramic or the like can be used as the material of the shielding cover 12.

Therefore, when the state of plasma is not measured, a shield cover moving signal for moving the shield cover 12 to the left in the axial direction of FIG. 1 is transmitted to the shield cover movable device 14, and the shield cover movable device 14 causes the shield cover 12 to move. Is moved to the left in the axial direction in FIG. 1 to arrange the shielding cover 12 in the state shown in FIG. In this way, by covering the electrode part 100b of the plasma measurement probe 10 with the shield cover 12, the electrode part 100b can be shielded from the plasma.

On the other hand, when the plasma state is measured by the plasma measuring probe 10, a shield cover moving signal for moving the shield cover 12 to move the shield cover 12 rightward from the state shown in FIG. Then, the shield cover moving device 14 moves the shield cover 12 to the right in the axial direction in FIG. By moving the shield cover 12, the electrode portion 100b of the plasma measurement probe 10 can be exposed to the plasma, and the plasma state can be measured by the plasma measurement probe 10.

FIG. 2 shows a state in which the plasma measuring probe 10 described above is arranged in the plasma generator 102. In addition, as an example of the shield cover movable device 14,
A configuration is disclosed in which the shield cover 12 is moved in the axial direction by the attraction force of the electromagnetic coil.

That is, the shield cover movable device 14 is provided on the inner peripheral surface of the cylindrical support member 16 and is provided with electromagnetic coils 18 and 20 which are axially spaced with a predetermined gap. The electromagnetic coil 18 is arranged on the electrode part 100 b side of the plasma measurement probe 10, while the electromagnetic coil 20 is arranged on the body part 10 of the plasma measurement probe 10.
It is arranged on the base side of 0a.

Further, these electromagnetic coils 18, 20
The switch 22 switches the connection with the power source 24 to select the excitation or the non-excitation.

Further, the shielding cover 12 has an iron piece 26 arranged on the outer peripheral surface of the main body portion 100a of the plasma measuring probe 10 on the base side.

The shield cover 12 covers the electrode portion 100b when the iron piece 26 is attracted to the electromagnetic coil 18, and the electrode portion 100b is exposed when the iron piece 26 is attracted to the electromagnetic coil 20. The dimensions are set so that

In the above configuration, the plasma generator 1
When the plasma in 02 is not measured, the switch 22 is switched to excite the electromagnetic coil 18, and the iron piece 26 is attracted by the electromagnetic coil 18 to move the shield cover 12 to the positional relationship shown in FIG. . As a result, the electrode portion 100b of the plasma measurement probe 10 is covered with the shield cover 12, and contact with the plasma in the plasma generator 102 is suppressed.

On the other hand, when measuring the plasma in the plasma generator 102, the switch 22 is switched to excite the electromagnetic coil 20, and the iron piece 26 is excited by the electromagnetic coil 20.
By suctioning, the shield cover 12 is moved to the right in the axial direction. Thereby, the plasma measurement probe 10
The electrode part 100b is exposed to the plasma in the plasma generator 102, and the state of the plasma can be measured.

That is, when the shield cover 12 covers the electrode portion 100b, it becomes possible to prevent the invasion of plasma into the electrode portion 100b.
Plasma contamination of b is prevented. Therefore, it is possible to prevent the occurrence of the deviation of the measurement of the plasma characteristics due to the change of the effective area of the electrode portion 100b due to the plasma contamination.

[0024]

Since the present invention is constructed as described above, it has the following effects.

In a plasma measuring probe arranged in the plasma generator for measuring the state of the plasma generated in the plasma generator, the electrode part of the plasma measuring probe is connected to the plasma generated in the plasma generator. A shielding member capable of shielding is provided, and the shielding member shields the electrode portion from the plasma generated in the plasma generator when the state of the plasma generated in the plasma generator is not measured by the plasma measurement probe. Therefore, since the electrode portion of the plasma measurement probe can be eliminated from the state of being constantly exposed to plasma, generation of plasma contamination in the electrode portion of the plasma measurement probe is suppressed, and the effective area of the electrode portion of the plasma measurement probe is reduced. No measurement of plasma state due to changes It is possible to prevent the occurrence.

Therefore, according to the plasma measuring probe of the present invention, there is no deviation in the measurement of the plasma state.
The reproducibility of the measurement can be secured, and the reliability of the measurement can be greatly improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory diagram of a plasma measurement probe according to an embodiment of the present invention.

FIG. 2 is a partially enlarged side sectional view of a plasma measurement probe according to an embodiment of the present invention in a state in which it is arranged in a plasma generator.

FIG. 3 is a schematic side view showing a conventional plasma measurement probe in a state of being arranged in a plasma generator.

[Explanation of symbols]

 10 Plasma Measurement Probe 12 Shielding Cover 14 Shielding Cover Moving Device 16 Cylindrical Support Member 18 Electromagnetic Coil 20 Electromagnetic Coil 22 Switch 24 Power Supply 26 Iron Piece 100a Main Body 100b Electrode 102 Plasma Generator 104 Vacuum Reaction Chamber

Claims (1)

[Claims] 1. A plasma measuring probe arranged in a plasma generator for measuring a state of plasma generated in the plasma generator, wherein an electrode portion of the plasma measuring probe is provided in the plasma generator. A shield member capable of shielding from the generated plasma, and when the state of the plasma generated in the plasma generator is not measured by the plasma measurement probe, the shield member causes the electrode portion to move to the plasma generator. A plasma measuring probe, characterized in that it is shielded from the plasma generated inside.