JPH06163186A - Plasma measuring probe - Google Patents

Abstract

PURPOSE:To achieve high accurate measuring a plasma parameter in plasma of large area by measuring plasma distribution in a vacuum vessel with a plurality of probes mounted to a mounting base moved to the right and left. CONSTITUTION:When a moving flange 12 is moved to the right and left by a driving gear 17, a supporting pipe 5 is guided by a groove of pulleys 4 and moved to the right and left. A plurality of probes 7a to 7c, mounted to a mounting base 6 in an internal end of the pipe 5, are moved to the right and left, to measure by plane at a time distribution of plasma generated in a vacuum vessel 1. Thus by simultaneously measuring many points by a plurality of the probes 7a to 7c, high density measuring a plasma parameter in plasma of large area can be effectively and properly performed, and further two-dimensional measurement can be performed.

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 suitable for measuring the plasma state of a plasma chemical vapor deposition apparatus.

[0002]

2. Description of the Related Art A conventional plasma measuring probe is shown in FIG.
As shown in the front view, one probe 7 covered with a ceramic coating is inserted into the wall of the vacuum chamber 1 where plasma is generated, and the linear plasma state is measured.
However, in such a plasma measuring probe, since the single probe 7 is moved in the linear direction, it is effective for measuring a small cylindrical container in which plasma is symmetrically generated along the central axis, but it is a box type. For a large area plasma in a vacuum container, only one-dimensional measurement is possible, and it is not suitable for measuring the spatial distribution due to the time change of plasma. In addition, in the Langmuir method usually used,
The probe characteristics may become blunt due to dirt on the probe surface, fluctuations in plasma, etc., and the plasma space potential may not be clear.

[0003]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and is a plasma measurement capable of effectively and accurately performing highly accurate measurement of plasma parameters in a large area plasma. It aims at providing the probe for.

[0004]

To this end, the present invention is directed to a pulley attached to a fixing flange fixed to an insertion port of a vacuum container in which plasma is generated, and a wall of the vacuum container slidably supported by the pulley. A support pipe protruding in and out of
Between a plurality of probes protruding from the mounting base provided at the inner end of the support pipe at a predetermined interval from each other, and between the movable flange and the fixed flange provided at the outer end of the support pipe. It is characterized by comprising a stretched flexible tube and a drive device for moving the moving flange toward or away from the fixed flange.

[0005]

In the plasma measuring probe of the present invention, by attaching a plurality of probes, the conventional linear measurement can be two-dimensionally measured, and the simultaneous multi-point measurement makes it possible to obtain information on the plasma at each probe position. Can be derived, and the distribution in space can be observed without causing a change over time. Further, if the support pipe, the probe, and the mounting base are configured to be separable, the probe and the like can be assembled and disassembled from the moving flange and the flexible tube attached to the vacuum container. Moreover, by using the emissive method as the probe, the probe characteristics that tend to be ambiguous in the Langmuir method are clarified.

[0006]

1 is a front view of the entire probe, FIG. 2 is a perspective view of a mounting base, and FIG. 3 is a sectional view showing a vacuum connector. 4 is a diagram showing the plasma measurement results of the conventional probe and this probe, FIG. 5 is a perspective view of a mounting base in which the emissive probes are distributed, FIG. 6 is an enlarged view of VI portion of FIG. 5, and FIG. It is an upper part sectional view of a stand.

First, in FIG. 1, a fixed flange 3 is attached to the insertion port 2 of the vacuum container 1 where plasma is generated, and three pulleys 4 are attached to the fixed flange 3. A support pipe 5 is supported on the pulley 4 so as to be slidable right and left in the groove, and is projected inside and outside the wall of the vacuum container 1. At the inner end of the support pipe 5, a mount 6 is attached.
2, the mounting base 6 has a box-shaped rail shape as shown in FIG. 2, and three probes 7a, 7b, 7c covered with a ceramic coating are provided on the mounting base 6 via an adjuster 8, respectively. It is fitted with a certain interval,
The adjuster 8 can be adjusted and fixed in any position in the vertical direction, and a spacer 9 can be incorporated between the adjusters 8 if necessary. As shown in FIG. 3, a vacuum connector 10 is attached to the mounting base 6, and a vacuum insulated cable 11 having a signal line and guided through the inside of the support pipe 5 holds a sufficient length in the vertical direction. Are connected to each other, and the vacuum insulated cable 11 similarly holds a sufficient length in the vertical direction, and each probe 7a ...
7c.

Then, returning to FIG. 1 again, a moving flange 12 is attached to the outer end of the support pipe 5, and a flexible tube surrounding the support pipe 5 is provided between the moving flange 12 and the fixed flange 3. 13 is stretched and is kept in vacuum up to the position of the moving flange 12. A connector 14 for extracting a signal to the atmosphere side is attached to the moving flange 12, and the outer end of the vacuum insulated cable 11 guided through the inside of the support pipe 5 is connected to the connector 14. The connector 14 has a probe changeover switch. 1
A measuring instrument 16 is connected via 5. On the atmospheric side, a drive device 17 for driving the moving flange 12 for moving the support pipe 5, the mounting base 6 and the probes 7a to 7c.
Is provided.

In such a device, by moving the moving flange 12 left and right by the driving device 17,
The support pipe 5 is guided by the groove of the pulley 4 and moves left and right,
The three probes 7a to 7c attached to the attachment table 6 at the inner end of the support pipe 5 move to the left and right to measure the distribution of plasma generated in the vacuum container 1 in a plane at a time. However, since the three probes 7a to 7c simultaneously measure multiple points, the measurement can be performed accurately even when the parameters in the plasma fluctuate with time. FIG. 4 shows a case (A) in which the measurement is repeated by the conventional apparatus and a case (B) in which the measurement is performed by the apparatus of the present invention. However, in the measurement of the device of the present invention, any distribution can be measured under the same conditions.

Next, in the case where a plurality of emissive probes are distributed in a plane on the mount at a predetermined interval,
Referring to FIGS. 5 to 7, in FIGS. 5 and 6, five glass-covered conductors 18 provided with a glass-covered 18 ′ are crossed in parallel vertically and horizontally, and the three-dimensionally crossed glass-covered conductors 18 are shown. A part of the glass coating 18 'is peeled off at the closest position, and one emissive probe 19 is formed by connecting each with a tungsten wire. A total of 25 emissive probes 19 are formed on the entire surface of the mounting base 6. Are distributed in a plane. As for the internal structure of the mounting base 6, as shown in the upper sectional view of FIG. 7, the upper end of the glass-coated conductive wire 18 is connected to the vacuum connector 10 via the terminal base 20 which also serves as tension adjustment. The glass-coated conductor wire 18 in the lateral direction as viewed from the side is also output from the connector. Thus, in this case, by using the emissive probe 19 in a flat shape, the plasma potential can be directly measured easily without measuring the IV characteristic, and the measurement at any point can be performed quickly. Therefore, it is possible to deal with the fluctuation of plasma and the change over time.

[0011]

In summary, according to the present invention, a pulley attached to a fixing flange fixed to an insertion port of a vacuum container where plasma is generated, and a wall of the vacuum container slidably supported by the pulley are provided. A projecting support pipe, a plurality of probes projecting from a mounting base provided at the inner end of the support pipe at a predetermined distance from each other, and a moving flange provided at the outer end of the support pipe. Equipped with a flexible tube stretched between the fixed flange and a drive device for moving the moving flange closer to or further from the fixed flange, it is possible to effectively measure plasma parameters in a large area plasma with high accuracy. The present invention is extremely useful industrially because a plasma measuring probe that can be accurately performed is obtained.

[Brief description of drawings]

FIG. 1 is a front view of the entire probe in one embodiment of a plasma measurement probe of the present invention.

FIG. 2 is a perspective view of a mounting base in the above.

FIG. 3 is a cross-sectional view showing the vacuum connector of the above.

FIG. 4 is a diagram showing plasma measurement results of a conventional probe and this probe.

FIG. 5 is a perspective view of a mounting base on which emissive probes are distributed.

6 is an enlarged view of a VI portion of FIG.

FIG. 7 is a top sectional view of the same mounting base.

FIG. 8 is a front view of a conventional probe.

[Explanation of symbols]

 1 Vacuum container 2 Insertion port 3 Fixed flange 4 Pulley 5 Support pipe 6 Mounting stand 7a, 7b, 7c Probe 8 Adjuster 9 Spacer 10 Vacuum connector 11 Vacuum insulation cable 12 Moving flange 13 Flexible tube 14 Connector 15 Probe changeover switch 16 Measuring instrument 17 Drive 18 Glass-coated conductor 19 Emissive probe 20 Terminal block

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Yoshikazu Nawata 1-1, Atsunoura-machi, Nagasaki City, Nagasaki Shipyard Co., Ltd. Inside the shipyard

Claims (2)

[Claims] 1. A pulley attached to a fixing flange fixed to an insertion port of a vacuum container where plasma is generated, a support pipe slidably supported by the pulley and protruding inside and outside a wall of the vacuum container. Between a plurality of probes protruding from the mounting base provided at the inner end of the support pipe at a predetermined interval from each other, and between the movable flange and the fixed flange provided at the outer end of the support pipe. A plasma measuring probe comprising: a stretched flexible tube; and a drive device for moving the moving flange toward or away from the fixed flange. 2. The probe for plasma measurement according to claim 1, wherein a plurality of emissive probes are distributed in a plane on the mounting base at a predetermined interval from each other.