JP2506030Y2 - Plasma processing equipment for painting - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention irradiates microwave plasma generated in a plasma generation furnace onto an object to be coated, particularly an olefin resin, housed in a vacuumed reaction chamber. Thus, the present invention relates to a coating plasma processing apparatus that performs microwave plasma pretreatment to improve the adhesion of the coating film.

[Conventional technology]

According to JP-A-60-217244, in order to prevent the reduction of the coating film adhesion strength due to the fluctuation of the plasma generation amount in this type of microwave plasma processing device easily and reliably, It has been proposed to monitor the plasma emission during plasma processing, based on the confirmation that there is a correlation with the plasma emission phenomenon. This makes it possible to prevent a decrease in the adhesion strength of the coating film by a simple method.

[Problems to be solved by the device]

On the other hand, during actual operation, the plasma state may deteriorate in the quartz tube, Teflon (registered trademark) joint, plasma irradiation tube, etc. in the process from the plasma generation furnace to the reaction chamber. In the case of sex, the degree of collapse tends to increase. Also, in the reaction chamber, plasma gas reacts with the volatile components due to the components volatilized from the object to be coated and deteriorates the plasma state. Especially, if the standing time after the steam cleaning in the previous step is short, the plasma state is significantly affected. There is.

In other words, when monitoring the amount of emitted light, the illuminance may change in the path from the plasma generation furnace to the reaction chamber, but in the above-mentioned JP-A-60-217244, in order to ensure monitoring accuracy, It has not been clarified whether or not the amount of light emission should be measured in the part.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a coating plasma processing apparatus that can more reliably monitor the adhesion strength based on the emission state of plasma.

[Means for solving the problem]

The present invention provides a coating film by generating microwave plasma in a plasma generation furnace by being supplied with a processing gas and microwaves, and irradiating the microwave plasma with a coating object housed in a vacuumed reaction chamber. In order to achieve the above-mentioned object, in a plasma processing apparatus for coating that performs microwave plasma pretreatment for improving the adhesion of the object, an optical sensor for detecting the brightness around the object to be coated is provided on the wall of the reaction chamber. In addition, an indicator that displays the brightness by using the detection signal of this optical sensor as an input, a comparator that detects that the detection signal falls below a reference level, and an alarm that operates in response to the detection signal of the comparator. It is characterized by having.

[Action]

During irradiation of microwave plasma to the object to be coated in the reaction chamber, the optical sensor detects the brightness in the reaction chamber and displays the level on the display to monitor the actual plasma generation amount effective for pretreatment. Let When the detection signal falls below the reference level, the comparator detects that it falls below and activates the alarm.

〔Example〕

1 and 2 show a plasma processing apparatus for coating according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 is a plasma generating furnace, which supplies microwaves supplied from a microwave oscillator 2 through a waveguide to O ₂ and N ₂ supplied from a gas tank 3 through a pipe.
To generate a microwave plasma. Reference numeral 5 denotes a reaction chamber, which is evacuated by a vacuum pump 6 and is irradiated with microwave plasma supplied from the plasma generation furnace 1 through a quartz tube through a plasma shower tube 7.

The reaction chamber 5 is formed in a cylindrical shape, and the walls on both sides are configured as doors 8 provided with a peephole 10, and a polypropylene bumper 9 is housed therein for processing. Peep window 10 provided at the center of one door 8
As shown in FIG. 2, a wide-angle condenser lens 12 for collecting plasma light in the entire reaction chamber 5, that is, the surrounding area of the bumper 9 is placed in front of the outside of the chamber and is visible to the processing gas. An optical sensor case 11 provided with an optical sensor 13 that outputs a photoelectric signal of a level corresponding to the illuminance around the area is screwed so as not to cause light leakage. Then, the amplifier 15 for the detection signal of the optical sensor 13, the display 16 for numerically displaying the brightness with the amplified signal as an input, the comparator 17 for detecting that the detection signal falls below the reference level, and the comparator Alarm device 18 that is, for example, a buzzer that operates in response to a detection signal
And are followed. Each of these parts is provided in a control panel 14 for operating the microwave oscillator 2 and the vacuum pump 6, and a blind lid is usually attached to the observation window 10 of the door 8 on the reaction side.

The operation of the coating plasma processing apparatus configured in this way is as follows.

When the operation is started by operating the control panel 14, the microwave plasma is applied to the bumper 9 from the plasma shower tube 7. At the same time, the optical sensor 13 receives the light emitted from almost the entire reaction chamber 5 including the entire circumference of the bumper 9 through the condenser lens 12,
A detection signal of a level corresponding to the illuminance is output. Therefore, the display 16 displays the lens numerically, and the plasma reaction state can be monitored. The alarm device 18 is also activated after tens of seconds in which an equilibrium state is reached after the start-up time of light emission. As a result, when the light emission level falls below a level that causes a problem in quality control, the comparator 17 detects this and causes the alarm 18 to generate an alarm sound.

It should be noted that the mounting position of the optical sensor is preferably mounted on the end wall in the cylindrical direction in order to monitor the entire region functioning for the reaction when the reaction chamber is cylindrically long as in the above-mentioned embodiment, but the shape is Depending on the case, it may be possible to mount it on a cylindrical surface or arrange a plurality of optical sensors to give an alarm when any one of them detects a low level. In short, the reaction chamber area is appropriately set according to the shape of the processed material.

[Effect of device]

As described above, according to the present invention, it is possible to reliably measure and monitor whether or not plasma processing can be performed over the entire area of an object to be coated by monitoring the brightness around the object to be coated in the reaction chamber. . Therefore, the plasma effective for the actual treatment can be monitored, and the generated vapor region of the object to be coated can be reliably monitored in consideration of the deterioration in the plasma transfer process.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a plasma processing apparatus for coating according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view and an attached circuit diagram of an illuminance sensor portion of the embodiment. 5 ... Reaction chamber, 9 ... Bumper, 13 ... Optical sensor.

Claims (1)

(57) [Scope of utility model registration request] Claim: What is claimed is: 1. A process gas and a microwave are supplied to generate a microwave plasma in a plasma generation furnace, and the microwave plasma is applied to an object to be coated contained in a reaction chamber which has been evacuated to form a coating film. In a plasma processing apparatus for coating that performs microwave plasma pretreatment to improve the adhesion of the film, an optical sensor is installed on the wall of the reaction chamber to detect the brightness around the object to be coated. It is provided with an indicator for displaying the brightness with a signal as an input, a comparator for detecting that the detection signal falls below a reference level, and an alarm device which operates in response to the detection signal of the comparator. Characteristic plasma processing equipment.