JP6339816B2 - Plasma processing judgment system - Google Patents

Description

  The present invention relates to a plasma processing determination system for determining the suitability of plasma processing by a plasma processing apparatus using an indicator.

  In recent years, plasma processing has been performed on objects to be processed in various fields, such as industrial objects to be processed such as circuit boards and assembly products, and medical objects to be processed such as instruments used in hospitals. As a useful technique, plasma processing using a plasma processing apparatus is employed. On the other hand, since the plasma cannot be visually confirmed, it may not be possible to determine whether or not the plasma processing is appropriately performed on the target object by observing the appearance of the target object. For this reason, as described in the following patent document, the development of an indicator whose optical characteristics change by plasma irradiation has been developed, and the suitability of plasma processing by a plasma processing apparatus can be determined using such an indicator. It has been judged.

JP 2013-178922 A JP 2005-315828 A

  By using the indicator described in the above-mentioned patent document, it is possible to determine the suitability of plasma processing by the plasma processing apparatus to some extent. However, when the optical characteristics of the indicator change significantly due to plasma irradiation, it is possible to appropriately determine the suitability of the plasma processing by the plasma processing apparatus. On the other hand, if the change in the optical characteristics of the indicator is not so large, there is a possibility that the suitability of the plasma processing by the plasma processing apparatus cannot be clearly determined. The present invention has been made in view of such circumstances, and an object of the present invention is to clearly and appropriately determine the suitability of plasma processing by the plasma processing apparatus regardless of the degree of change in the optical characteristics of the indicator. It is to judge.

In order to solve the above-mentioned problems, a plasma processing determination system described in the present application uses an indicator whose optical characteristics change due to plasma irradiation, and determines whether or not plasma processing by a plasma processing apparatus is appropriate. A detection sensor for detecting an index value indicating an optical characteristic of the indicator plasma-processed by the plasma processing apparatus, and the index value detected by the detection sensor is partitioned by a set value. And the index value detected by the detection sensor is included in the other region partitioned by the set value, when the plasma processing apparatus determines that the plasma processing is appropriately performed. The plasma processing apparatus determines that the plasma processing is not properly performed. A plasma processing determination system comprising a decision device, the index value, characterized in that at least one of a value indicating the reflectance value indicating the transmittance of light and the light.

  In the plasma processing determination system described in the present application, an index value indicating an optical characteristic of an indicator plasma processed by the plasma processing apparatus is detected by a detection sensor. Then, when the index value detected by the detection sensor is included in one of the areas defined by the set value, it is determined that the plasma processing by the plasma processing apparatus is appropriately performed, and is detected by the detection sensor. When the index value is included in the other region partitioned by the set value, it is determined that the plasma processing by the plasma processing apparatus is not properly performed. That is, the change in the optical characteristic of the indicator is digitized, and the suitability of the plasma treatment by the plasma treatment apparatus is determined based on the digitized value and the set value. Thereby, for example, even if the change in the optical characteristics of the indicator is small, it is possible to clearly and appropriately determine whether the plasma processing by the plasma processing apparatus is appropriate.

It is a top view which shows the atmospheric pressure plasma generator which is an Example of this invention. It is a schematic sectional drawing which shows the plasma irradiation head with which the atmospheric pressure plasma generator of FIG. 1 is provided. It is a side view which shows the transmittance | permeability detector with which the atmospheric pressure plasma generator of FIG. 1 is provided. It is a block diagram which shows the control apparatus with which the atmospheric pressure plasma generator of FIG. 1 is provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as modes for carrying out the present invention.

<Configuration of atmospheric pressure plasma generator>
FIG. 1 shows an atmospheric pressure plasma generator 10. The atmospheric pressure plasma generation apparatus 10 is an apparatus that irradiates an object to be processed with plasma generated under atmospheric pressure, and is an apparatus that can determine the suitability of plasma processing using the irradiated plasma. The atmospheric pressure plasma generator 10 includes a transfer device 12, a plasma irradiation head 14, and a transmittance detector 16.

  The conveying device 12 has a pair of conveyor belts 20, and the pair of conveyor belts 20 are disposed on the base 22 so as to be parallel to each other and extend in a predetermined direction. The pair of conveyor belts 20 support a mounting plate 24 for mounting the object 23 to be processed, and convey the mounting plate 24 in a predetermined direction by driving an electromagnetic motor (see FIG. 4). To do. Further, the transport device 12 has a holding device (see FIG. 4) 28, and the placing plate 24 supported by the conveyor belt 20 is fixedly held at a predetermined position by the holding device 28.

  The plasma irradiation head 14 is a working head that irradiates plasma at atmospheric pressure, and is fixed to the first beam portion 30. The first beam portion 30 is overlaid on the base 22 and is disposed so as to straddle the pair of conveyor belts 20. The plasma irradiation head 14 is fixed to the first beam portion 30 so as to be positioned above the pair of conveyor belts 20. As shown in FIG. 2, the plasma irradiation head 14 has a housing 32, and a reaction chamber 34 is formed inside the housing 32. A pair of electrodes 36 are disposed inside the reaction chamber 34. Each electrode 36 is generally L-shaped, and each end portion faces each other.

  The housing 32 of the plasma irradiation head 14 is formed with an inflow path 38 for allowing a processing gas to flow into the reaction chamber 34. An end portion of the inflow passage 38 on the reaction chamber 34 side is opened between a pair of opposed electrodes 36. On the other hand, a processing gas supply device (see FIG. 4) 40 is connected to the end of the inflow path 38 opposite to the reaction chamber 34. The processing gas supply device 40 is a device that supplies a processing gas obtained by mixing an inert gas such as a rare gas or nitrogen gas and an active gas such as oxygen at a predetermined ratio. As a result, the processing gas is supplied to the reaction chamber 34 via the inflow path 38.

  A plurality of air outlets 46 are formed in the housing 32 of the plasma irradiation head 14 so as to face the inflow path 38. That is, the inflow passage 38 and the plurality of outlets 46 are formed in the housing 32 so as to sandwich the pair of electrodes 36.

Further, the transmittance detector 16 includes a projector 50 and a light receiving sensor 52 as shown in FIG. The projector 50 is fixed to the second beam portion 54. The second beam portion 54 is overlaid on the base 22 and is disposed so as to straddle the pair of conveyor belts 20. The light projector 50 is fixed to the second beam portion 54 so as to be positioned above the pair of conveyor belts 20. Note that the second beam portion 54 is disposed on the downstream side of the first beam portion 30 in the conveyance direction of the conveyance device 12. On the other hand, the light receiving sensor 52 is disposed on the base 22 between the pair of conveyor belts 20 and faces the projector 50. For this reason, the mounting plate 24 supported by the pair of conveyor belts 20 passes above the light receiving sensor 52, that is, between the light projector 50 and the light receiving sensor 52 when being transported.

  The atmospheric pressure plasma generator 10 further includes a control device 70 as shown in FIG. The control device 70 includes a controller 72, a plurality of drive circuits 76, and a plurality of control circuits 78. The plurality of drive circuits 76 are connected to the electromagnetic motor 26, the holding device 28, and the processing gas supply device 40. The control circuit 78 is connected to the electrode 36. The controller 72 includes a CPU, a ROM, a RAM, and the like, mainly a computer, and is connected to a drive circuit 76 and a control circuit 78. Thereby, the operation of the transfer device 12 and the plasma irradiation head 14 is controlled by the controller 72. Further, the controller 72 is in contact with the transmittance detector 16 and acquires the detection result by the transmittance detector 16. Further, the controller 72 is connected to the panel 80 via the control circuit 78. The panel 80 displays information necessary for work by the atmospheric pressure plasma generator 10 and is controlled by the controller 72.

<Plasma treatment with atmospheric pressure plasma generator>
In the atmospheric pressure plasma generation apparatus 10, the processing gas is converted into plasma in the plasma irradiation head 14 by the above-described configuration, and the object to be processed 23 conveyed by the conveying apparatus 12 is irradiated with plasma, thereby the object to be processed. 23 is subjected to a plasma treatment. Specifically, according to a command from the controller 72, the mounting plate 24 on which the workpiece 23 is mounted is transported to the lower side of the plasma irradiation head 14 and is fixedly held by the holding device 28 at that position. . Next, the processing gas supply device 40 supplies the processing gas to the inflow path 38 in the plasma irradiation head 14 according to a command from the controller 72. As a result, the processing gas flows into the reaction chamber 34.

  In the reaction chamber 34, a voltage is applied to the pair of electrodes 36 at a predetermined timing according to a command from the controller 72, and a current flows between the pair of electrodes 36. Thereby, a discharge is generated between the pair of electrodes 36, and the processing gas is turned into plasma by the discharge. And plasma blows out from the blower outlet 46. As a result, the object to be processed 23 positioned below the plasma irradiation head 14 is irradiated with plasma, and the object to be processed 23 is subjected to plasma processing. When the plasma processing by the plasma irradiation head 14 is completed, the mounting plate 24 is transported to the downstream side, and the workpiece 23 is unloaded from the atmospheric pressure plasma generator 10.

<Plasma treatment suitability determination>
In the atmospheric pressure plasma generator 10, as described above, the plasma processing is performed on the object 23 by the plasma irradiated from the plasma irradiation head 14. However, due to insufficient voltage applied to the electrode 36, insufficient flow rate of the processing gas supplied to the reaction chamber 34, or the like, the processing gas may not be appropriately converted into plasma, and the plasma processing on the object 23 may not be performed properly. is there. For this reason, in the atmospheric pressure plasma generator 10, the suitability of the plasma treatment by the plasma irradiation head 14 is determined using an indicator.

  Specifically, the indicator is placed on the placement plate 24 as the object to be processed 23, and the placement plate 24 is set on the conveyor belt 20 of the transport device 12. Then, according to the procedure described above, the indicator is subjected to plasma treatment by the plasma irradiation head 14. This indicator is one whose transmittance is reduced by plasma irradiation. Since the indicator whose transmittance is changed by plasma irradiation is a known indicator, detailed description thereof is omitted. However, as described in JP 2013-178922 A, hydrogen ions obtained by nitrogen oxides are used. An indicator comprising a composition that changes by reacting with azobenzene, a composition comprising an azo-based dye, a nitrogen-containing polymer, and a cationic surfactant, as described in JP-A-2005-315828 An indicator or the like including an object can be employed.

  When the plasma processing by the plasma irradiation head 14 is completed, the indicator is transported to the lower side of the projector 50 of the transmittance detector 16 together with the mounting plate 24 according to a command from the controller 72. Next, the projector 50 irradiates laser light toward the light receiving sensor 52 according to a command from the controller 72, and the light receiving sensor 52 receives the laser light transmitted through the indicator and the mounting plate 24. A transparent acrylic plate is used as the mounting plate 24 at the time of measuring the transmittance.

  When receiving the laser light, the light receiving sensor 52 transmits a detection value of the received light to the controller 72. Then, the controller 72 calculates the transmittance based on the received detection value. Further, the controller 72 determines whether the calculated transmittance is equal to or less than the first threshold value. As described above, the transmittance of the indicator is reduced by the plasma irradiation, and the first threshold value is set to the maximum value of the transmittance of the indicator when the indicator is appropriately irradiated with the plasma. For this reason, when the transmittance calculated by the controller 72 is equal to or less than the first threshold, it is determined that the indicator is appropriately irradiated with plasma. That is, it is determined that the plasma processing by the plasma irradiation head 14 is being performed appropriately. Thereby, it is possible to appropriately perform the plasma processing by the plasma irradiation head 14.

  On the other hand, when the transmittance exceeds the first threshold value, it is determined whether or not the transmittance is equal to or less than the second threshold value. The second threshold value is set to the maximum value of the transmittance of the indicator when the indicator is slightly irradiated with plasma, and is a value larger than the first threshold value. For this reason, when the transmittance is equal to or lower than the second threshold, it is determined that the indicator is slightly irradiated with plasma. However, since the amount of plasma irradiation is small, appropriate plasma treatment cannot be performed. For this reason, a comment is displayed on the panel 80 that the appropriate plasma treatment cannot be performed because the amount of plasma irradiation is small. Thus, the operator can perform a treatment for increasing the plasma irradiation amount, and can perform an appropriate treatment against a decrease in the plasma irradiation amount.

  When the transmittance exceeds the second threshold, it is determined that the plasma is hardly irradiated on the indicator. For this reason, since the plasma is hardly irradiated on the panel 80, a comment indicating that appropriate plasma processing cannot be performed is displayed. As a result, the operator can search for a factor that does not generate plasma and can perform a predetermined treatment for the factor.

  Note that the controller 72 of the control device 70 has a determination unit 88 as shown in FIG. 4 as a functional unit for determining the suitability of plasma processing by the plasma irradiation head 14.

  As described above, in the atmospheric pressure plasma generator 10, the transmittance of the indicator subjected to the plasma treatment by the plasma irradiation head 14 is measured by the transmittance detector 16, and whether or not the transmittance is equal to or less than the first threshold value. Accordingly, the suitability of the plasma treatment by the plasma irradiation head 14 is determined. This makes it possible to clearly and appropriately determine whether or not the plasma treatment by the plasma irradiation head 14 is appropriate.

  Further, in the atmospheric pressure plasma generation apparatus 10, when it is determined that the plasma treatment by the plasma irradiation head 14 is not properly performed, the measured transmittance is equal to or less than the second threshold value that is larger than the first threshold value. It is determined whether there is any. At this time, if the transmittance is equal to or lower than the second threshold value, it is determined that the indicator is slightly irradiated with plasma, and if the transmittance exceeds the second threshold value, the indicator is almost irradiated with plasma. It is determined that it has not been done. Each determination result is displayed on the panel 80. Thereby, the operator can perform a treatment according to the determination result displayed on the panel 80, and can appropriately inspect and repair the plasma irradiation head 14.

  Incidentally, in the above embodiment, the plasma irradiation head 14 is an example of a plasma processing apparatus. The transmittance detector 16 is an example of a detection sensor. The determination unit 88 is an example of a determination device. The system configured by the transmittance detector 16 and the determination unit 88 is an example of a plasma processing determination system. The first threshold is an example of a set value. The second threshold value is an example of a second setting value.

  In addition, this invention is not limited to the said Example, It is possible to implement in the various aspect which gave various change and improvement based on the knowledge of those skilled in the art. Specifically, for example, in the above embodiment, an indicator whose transmittance is changed by plasma irradiation is adopted, but various indicators are adopted as long as the optical property is changed by plasma irradiation. It is possible. Here, the optical characteristics change depending on the wavelength of light, the amount of reflection, energy, vividness, etc., for example, adopting an indicator that changes reflectance, brightness, saturation, hue, luminance, etc. It is also possible to determine the suitability of the plasma treatment by measuring changes in reflectance, brightness, saturation, hue, brightness, and the like.

  Moreover, in the said Example, although the indicator whose optical characteristic falls by plasma irradiation is employ | adopted, it is possible to employ | adopt the indicator whose optical characteristic becomes high by plasma irradiation. However, when an indicator whose optical characteristics are enhanced by plasma irradiation is employed, when the index value indicating the optical characteristics is equal to or higher than the first threshold, the plasma processing by the plasma irradiation head 14 is performed as follows: When it is determined that it is appropriately performed and is less than the first threshold value, it is determined that the plasma processing by the plasma irradiation head 14 is not appropriately performed. The second threshold value is set to a value smaller than the first threshold value, and when the index value indicating the optical characteristic is less than the first threshold value and equal to or greater than the second threshold value, the plasma irradiation amount is set. When it is determined that the amount is less than the second threshold value, it is determined that the plasma is hardly irradiated.

  In the above embodiment, the determination unit 88 for determining the suitability of the plasma treatment by the plasma irradiation head 14 is provided in the control device 70 that controls the operation of the atmospheric pressure plasma generator 10. The unit 88 and the control device 70 can be separate devices.

  In addition, the object to be processed 23 to be subjected to plasma processing of the atmospheric pressure plasma generator 10 is not particularly limited, and is a medical object such as an industrial object to be processed such as a circuit board or an assembly product, or a device used in a hospital or the like. It is possible to employ members in various fields such as the object to be processed.

  14: Plasma irradiation head (plasma processing apparatus) 16: Transmittance detector (detection sensor) (plasma processing determination system) 88: Determination unit (determination apparatus) (plasma processing determination system)

Claims (2)

In the plasma processing determination system for determining the suitability of the plasma processing by the plasma processing apparatus, using an indicator whose optical characteristics change by plasma irradiation,
The plasma processing judgment system is
A detection sensor that detects an index value indicating an optical characteristic of the indicator that has been plasma processed by the plasma processing apparatus;
When the index value detected by the detection sensor is included in one of the areas defined by the set value, it is determined that the plasma processing by the plasma processing apparatus is appropriately performed and detected by the detection sensor has been the index value, if included in the other region partitioned by the set value, at a plasma processing determination system comprising a judgment device that plasma processing by the plasma processing apparatus is determined not done properly There,
The index value is
A plasma processing determination system characterized by being at least one of a value indicating light transmittance and a value indicating light reflectance . The determination device is
When it is determined that the plasma processing by the plasma processing apparatus is not properly performed, the index value detected by the detection sensor is divided into two by the second set value included in the other region 2. The plasma processing determination system according to claim 1, wherein it is determined in which of the regions.

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