JP2006275584A - Measuring probe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measuring probe capable of condensing only the emission of plasma itself without receiving disturbance such as scattered light or the like even if the distance between the plasma electrodes of a plasma discharge processor is narrow or a discharge space has any shape. <P>SOLUTION: The measuring probe 1 is equipped with a photoconductive member 2 for transmitting light data for use in the measurment of the spectral intensity of the plasma P produced between the plasma electrodes E1 and E2 in the plasma discharge processor D, a condenser lens 3 for condensing the emission of the plasma P to the end surface of the photoconductive member 2 and the slit member 4 having a plurality of slits 6 arranged between the condensing lens 3 and the plasma electrodes E1 and E2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a measurement probe, and more particularly to a measurement probe for measuring the spectral intensity of plasma generated between plasma electrodes of a plasma discharge processing apparatus.

  Recently, plasma discharge processing technology has been widely used for various processes such as film formation, etching, and cleaning on a substrate. Plasma discharge treatment is usually performed by introducing a gas into a discharge space formed between a pair of opposed electrodes, so-called plasma electrodes, and applying a high voltage to the plasma electrode to convert the gas in the discharge space into plasma. Is called.

Conventionally, such plasma discharge treatment is normally performed in a vacuum chamber of a plasma discharge treatment apparatus with a low pressure of about several Pa, and the spectral intensity of the plasma generated between the plasma electrodes is measured between the lens and the light. Plasma emission is collected by a condensing lens by a measurement probe equipped with a fiber or the like and incident on an optical fiber or the like, and the optical information is transmitted to a spectroscope or the like (for example, Patent Document 1) reference).
JP 10-104073 A

  In such a conventional plasma discharge processing apparatus that performs processing in a low-pressure environment, the gap between the plasma electrodes can be made relatively wide. However, in a plasma discharge treatment apparatus that performs discharge treatment under a pressure in the vicinity of atmospheric pressure that has been developed in recent years, the distance between the plasma electrodes must be narrowed to about several tens of μm to 1 mm.

  In recent years, a plasma discharge processing apparatus or the like in which a plasma electrode is not a simple parallel plate shape, for example, a single or a plurality of second electrodes are opposed to a drum-shaped first electrode has been developed. Yes. For this reason, the discharge space formed between the plasma electrodes has various shapes other than the space having a plane as a boundary.

  When the spectral intensity of the plasma is measured with the conventional measurement probe as described in Patent Document 1 for such a plasma discharge processing apparatus in which the gap between the plasma electrodes is narrow or the discharge space has a complicated shape, scattered light is obtained. The measurement results are susceptible to disturbance due to the influence of the above.

  That is, as shown in FIG. 5A, in the conventional measurement probe 100, the light collected by the condenser lens 101 is transmitted through the optical fiber 102 and sent to a spectroscope (not shown). As shown in FIG. 5B, the range focused by the lens 101 is a comparison including the plasma electrode of the plasma discharge processing apparatus D, that is, the portion of the plasma P generated in the gap between the first electrode E1 and the second electrode E2. Wide range.

  The light condensed on the condenser lens 101 in this state includes not only light emitted from the plasma itself but also scattered light of light emitted from the plasma P by the first electrode E1 and the second electrode E2, for example. included. When such scattered light enters the optical fiber 102 via the condenser lens 101 and is dispersed, a large amount of noise caused by unevenness or dirt on the electrode surface contained in the scattered light is measured with a certain level of intensity. Therefore, it is difficult to accurately measure the spectral intensity of the plasma P.

  Therefore, there is a demand for the development of a measurement probe that can collect only light emitted from the plasma P itself without being affected by scattered light. 5A is a side view of the plasma discharge processing apparatus D provided with the drum-shaped first electrode E1, and FIG. 5B is the same plasma discharge processing apparatus D viewed from the measurement probe 100 side. FIG.

  Therefore, the present invention provides a measurement probe capable of condensing only light emitted from plasma without being affected by disturbance such as scattered light regardless of the distance between plasma electrodes of the plasma discharge processing apparatus or the shape of the discharge space. The purpose is to provide.

In order to solve the above-mentioned problem, the measurement probe according to claim 1 comprises:
An optical member for transmitting optical information for measuring the spectral intensity of the plasma generated between the plasma electrodes in the plasma discharge treatment apparatus;
A condensing lens for condensing the plasma emission on the end face of the optical member;
It is provided with the slit member which is arrange | positioned between the said condensing lens and the said plasma electrode, and has a some slit.

  According to the first aspect of the present invention, the measuring probe blocks scattered light from the plasma electrode among the plasma emission generated between the plasma electrodes of the plasma discharge processing apparatus at a portion other than the slit of the slit member. As light information for measuring the spectral intensity of the plasma generated between the plasma electrodes in the plasma discharge processing device, the light emitted from the plasma that has passed through is collected by the condenser lens and incident on the end face of the light guide member. To transmit.

  According to a second aspect of the present invention, in the measurement probe according to the first aspect, the plurality of slits of the slit member are a distance between plasma electrodes of a plasma discharge processing apparatus and a discharge space formed between the plasma electrodes. The slit pattern is determined according to the shape.

  According to the invention described in claim 2, the slit member includes a plurality of slits having a slit pattern determined according to the distance between the plasma electrodes of the plasma discharge processing apparatus and the shape of the discharge space formed between the plasma electrodes. The light emitted directly from the plasma to the outside passes through these slits, and the scattered light reflected by the plasma electrode hardly passes.

  According to a third aspect of the present invention, in the measurement probe according to the second aspect, the slit member can be replaced with another slit member having a different slit pattern.

  According to the third aspect of the present invention, a plurality of slit members having different slit patterns are formed so as to correspond to plasma discharge processing apparatuses having different discharge space shapes and the like, and are replaced as necessary. In addition, when using the measurement probe for the same plasma discharge processing apparatus, the slit probe is replaced with another slit member having a different slit shape, slit width, slit pattern, or the like.

  According to the first aspect of the present invention, the measuring probe blocks scattered light from the plasma electrode among the plasma emission generated between the plasma electrodes of the plasma discharge processing apparatus at a portion other than the slit of the slit member. As light information for measuring the spectral intensity of the plasma generated between the plasma electrodes in the plasma discharge processing device, the light emitted from the plasma that has passed through is collected by the condenser lens and incident on the end face of the light guide member. Configured to transmit.

  By comprising in this way, it becomes possible to interrupt | block most of the scattered light reflected by the plasma electrode of the plasma discharge processing apparatus in parts other than the slit of a slit member. Therefore, in the measurement probe of the present invention, the light that has passed through the slit of the slit member can be directly emitted to the outside from the plasma containing almost no scattered light. It is possible to transmit optical information that hardly contains noise caused by dirt or the like.

  According to the invention described in claim 2, the slit member includes a plurality of slits having a slit pattern determined according to the distance between the plasma electrodes of the plasma discharge processing apparatus and the shape of the discharge space formed between the plasma electrodes. The light emitted directly from the plasma to the outside passes through these slits, and the scattered light reflected by the plasma electrode hardly passes.

  Therefore, even if the distance between the plasma electrodes of the plasma discharge processing apparatus is narrow or the shape of the discharge space is irregular, by forming a slit pattern of a plurality of slits in the slit member so as to correspond to it, Scattered light can be almost blocked, and the effect of the invention of claim 1 can be exhibited more accurately.

  According to the third aspect of the present invention, a plurality of slit members having different slit patterns are formed so as to correspond to plasma discharge processing apparatuses having different discharge space shapes and the like, and are replaced as necessary. Moreover, when using a measurement probe with respect to the same plasma discharge processing apparatus, it comprised so that it might replace | exchange for another slit member from which the shape of a slit, a slit width, a slit pattern, etc. differ.

  Therefore, when the measurement probe is used in another plasma discharge processing apparatus having a different discharge space shape or the like, the effect of the invention described in each of the claims can be easily obtained by replacing the slit probe with another slit member having a different slit pattern. It can be demonstrated. In addition, by using different slit members with different slit shapes, slit widths, slit patterns, etc. for the same plasma discharge treatment apparatus, optical information transmitted through the optical member can be made more noise-free. Alternatively, it is possible to increase the amount of light incident on the optical member.

  Embodiments of a measurement probe according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram illustrating the configuration of the measurement probe according to the present embodiment. The measurement probe 1 of the present embodiment includes an optical member 2, a condenser lens 3, and a slit member 4.

  The plasma discharge treatment apparatus D used in the present embodiment is a plasma discharge treatment apparatus that performs plasma discharge treatment under a pressure close to atmospheric pressure. In FIG. 1, a drum-like shape similar to that shown in FIG. Although the plasma discharge processing apparatus having the first electrode E1 is shown, the present invention is not limited to this. 1 shows a state in which the measurement probe 1 collects light from the end face side of the drum-shaped first electrode E1 in the plasma discharge processing apparatus D, but from the side of the first electrode E1 and the second electrode E2. It is also possible to arrange so as to collect light.

  In this embodiment, the optical member 2 is made of an optical fiber as shown in FIG. 2A, and is composed of a bundle of a plurality of optical fibers as shown in the enlarged view of FIG. The shape of the optical member 2 can be changed flexibly, and a spectral intensity measuring device 10 is attached to one end side of the optical member 2.

  The other end side of the optical member 2 is an incident surface 5, and the optical member 2 is connected to the incident surface 5 by a support member (not shown) through the condenser lens 3 and the slit member 4. The position is fixed so as to face the gap between the first electrode E1 and the second electrode E2.

  The light collected by the condenser lens 3 is incident on the incident surface 5 of the optical member 2, and the light incident on the incident surface 5 passes through the interior of the optical member 2 as optical information and has a spectral intensity. It is transmitted toward the measuring instrument 10. The optical member 2 can be made of a single optical fiber or other material capable of transmitting optical information.

  The spectral intensity measuring device 10 measures the spectral intensity of the plasma P generated between the plasma electrodes E1 and E2 in the plasma discharge processing apparatus D based on the optical information transmitted through the optical member 2. . Further, the spectral intensity measuring device 10 can be disposed outside the plasma discharge processing apparatus D by giving the optical member 2 a sufficient length.

  A convex lens-like condensing lens 3 supported by a holding means (not shown) and movable in the optical axis direction is disposed on the plasma discharge processing apparatus side of the incident surface 5 of the light guide member 2. The condensing lens 3 condenses the light emission of the plasma P in the discharge space S formed between the plasma electrodes E1 and E2 of the plasma discharge processing apparatus D and enters the light incident surface 5 so as to be in focus. It is arranged to let you.

  A plurality of condensing lenses 3 can be arranged, and a concave lens or a special lens having various functions can be combined. In addition, the condenser lens 3 can be focused on an arbitrary position of the plasma P formed in the discharge space S between the plasma electrodes E1 and E2 by moving one or a plurality of lenses. Yes.

  Between the condenser lens 3 and the plasma discharge treatment apparatus D, a slit member 4 having a plurality of slits 6 is disposed by being supported by a support means (not shown). In the present embodiment, the slit member 4 has a distance between the plasma electrodes E1 and E2 of the plasma discharge processing apparatus D and plasma as shown in FIGS. 3A to 3C when viewed from the condenser lens 3 side. A plurality of slits 6 having a specific slit pattern are formed at positions corresponding to the discharge space S according to the shape of the discharge space S formed between the electrodes E1 and E2.

  In the present embodiment, the slit member 4 has different slit patterns of the plurality of slits 6 depending on the shape of the discharge space S of the plasma discharge processing apparatus D used as shown in FIGS. It can be exchanged with other slit members. Moreover, it is also possible to replace and use the slit member 4 having a different shape, slit width, slit pattern, etc. for the same plasma discharge processing apparatus D.

  In addition, although the case where the slit 6 is formed in a circular shape is shown in FIG. 3, for example, it is also possible to form the slit 6 in a thin line shape, or in an appropriately effective shape and length. is there. Moreover, although the slit member 4 is comprised in square shape in FIG. 3, it can be formed in arbitrary shapes.

  Further, the measurement information of the spectral intensity of the plasma P formed between the plasma electrodes E1 and E2 obtained by the spectral intensity measuring device 10 is transmitted to a control device (not shown) of the plasma discharge processing apparatus D, and the plasma electrodes E1 and E2 are transmitted. It is also possible to automatically adjust the distance between them and the voltage applied to the electrodes.

  Next, the operation of the measurement probe 1 according to this embodiment will be described.

  When a voltage is applied to the first electrode E1 and the second electrode E2 that are plasma electrodes of the plasma discharge treatment apparatus D, the gas introduced into the discharge space S formed between the plasma electrodes E1 and E2 is turned into plasma. Light is emitted and light is emitted from the plasma P to the surroundings. A part of the light emission of the plasma P is directly emitted from the discharge space S to the outside, and the other light emission is emitted to the outside after being reflected by the first electrode E1 and the second electrode E2.

  A part of the light emitted from the plasma P is directed toward the measurement probe 1. At that time, as shown in FIG. 4, the light L <b> 1 directed to the slit 6 formed in the slit member 4 passes through the slit 6, is diffracted and spreads, and is condensed and refracted by the optical member 2. Is incident on the incident surface 5.

  However, if the slit member 4 does not exist, most of the scattered light L2 and L3 collected on the condenser lens 3 is blocked by the slit member 4 and is not condensed on the condenser lens 3, and thus the optical member. 2 is not incident.

  In this way, the light that has passed through the slit 6 of the slit member 4 is light emission of the plasma P that is radiated directly to the outside and contains almost no scattered light, and such light is incident on the incident surface 5 of the optical member 2. And transmitted to the spectral intensity measuring instrument 10 as optical information. Then, the spectral intensity measuring device 10 measures the spectral intensity of the plasma P generated between the plasma electrodes E1 and E2 in the plasma discharge processing apparatus D.

  When measuring the spectral intensity of the plasma P of another plasma discharge processing apparatus D, the measurement is performed by exchanging the slit member 4 provided with slits 6 having slit patterns corresponding to the discharge spaces S of the apparatus D. I do. Moreover, it is also possible to replace the same plasma discharge processing apparatus D with another slit member 4 having a different shape, slit width, slit pattern, or the like.

  As described above, according to the measurement probe 1 according to the present embodiment, the measurement probe 1 is provided with the slit member 4 having the slit 6 having the slit pattern corresponding to the shape or the like of the discharge space S of the plasma discharge processing apparatus D. This makes it possible to block most of the scattered light reflected by the plasma electrode of the plasma discharge treatment apparatus D, that is, the first electrode E1 and the second electrode E2.

  Therefore, in the measurement probe 1 of the present embodiment, the light that has passed through the slit 6 of the slit member 4 can be emitted from the plasma P that is emitted directly to the outside and contains almost no scattered light. Thus, it is possible to transmit optical information containing almost no noise due to the unevenness or dirt of the plasma electrodes E1 and E2 to the spectral intensity measuring instrument 10.

  Further, as shown in FIGS. 3A to 3C, the distance between the plasma electrodes E1 and E2 of the plasma discharge processing apparatus D is narrow, or the discharge space S can have any shape. As described above, by forming the slit pattern of the plurality of slits 6 in the slit member 4, it is possible to block disturbances such as scattered light.

  Although the light emission and scattered light of the plasma P are blocked by the slit 6, the light emission of the plasma P under a pressure near atmospheric pressure is sufficiently strong, and the light passing through the plurality of slits 6 is sufficient. It has been confirmed that the spectral intensity of the plasma P can be measured.

It is a figure explaining the structure of the measurement probe which concerns on this embodiment. It is a figure explaining the structure of the optical member of the measurement probe of FIG. 1, (A) is a general view, (B) is an enlarged view of an incident surface part. It is a figure explaining the structure of the slit member of the measurement probe of FIG. It is a figure explaining the state by which scattered light is interrupted | blocked by the slit member of the measurement probe of FIG. It is a figure explaining the condensing state by the conventional measurement probe, (A) is the figure seen from the side, (B) is the figure seen from the measurement probe side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Measurement probe 2 Optical member 3 Condensing lens 4 Slit member 6 Slit D Plasma discharge processing apparatus E1 1st electrode E2 2nd electrode P Plasma S Discharge space

Claims (3)

An optical member for transmitting optical information for measuring the spectral intensity of the plasma generated between the plasma electrodes in the plasma discharge treatment apparatus;
A condensing lens for condensing the plasma emission on the end face of the optical member;
A measurement probe comprising a slit member disposed between the condenser lens and the plasma electrode and having a plurality of slits.   The slit pattern of the plurality of slits of the slit member is determined according to a distance between plasma electrodes of a plasma discharge processing apparatus and a shape of a discharge space formed between the plasma electrodes. The measurement probe according to 1.   The measurement probe according to claim 2, wherein the slit member is exchangeable with another slit member having a different slit pattern.

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