JPH11183111A - Method for measuring change in film thickness and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the speedy and accurate simultaneous measurement of film thickness and variations in film thickness without individually measuring the substrate surface and film forming surface of a body to be measured by measuring film thickness by an eddy current sensor and calculating changes in film thickness on the basis of the measurement results of a contact-type displacement measuring device which scans simultaneously with the eddy current sensor. SOLUTION: An object to be measured W is placed at a predetermined location on a measuring table 2 on a base 1 and is fixed by a fixing means. Next, the location of a part to be measured of the object W is matched to the location of a measuring terminal 8. With this state maintained, a contact-type displacement detector 5 is lowered by a vertically driving machine provided for a stand 3. The measuring terminal 8 of an eddy current sensor 7 integrally installed to the displacement detector 5 comes into contact with the surface of a film to be measured W2 of the object W. Next, the measuring table 2 is moved by a predetermined amount and is set in an X-direction. The scanning of the table 2 is started by an instruction from a control part 10, and measurement data from the eddy current sensor 7 and the displacement detector 5 is inputted to a measurement data processing part 11. In other words, the amount of displacement of the detector 5 is related to the data of the sensor 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring the thickness of a non-conductive film formed on the surface of a conductor, the change in the thickness and the unevenness of the thickness.

[0002]

2. Description of the Related Art A component in which a nonconductive film is formed on a surface of a metal body by coating or the like is widely used in many electronic devices such as a roller of an electronic copying machine.

[0003] Since these film thicknesses and film thickness unevenness are closely related to the function of the component, predetermined management is performed for each function.

For example, an eddy current sensor, a contact type displacement detector, and a dimension measuring device are used as a method of measuring the thickness of the coated film and the unevenness of the film thickness.

That is, when using an eddy current sensor,
The measurement terminal of the eddy current sensor is brought into contact with the surface of the film of the object to be measured, and the distance from the position to the surface of the base material as the base is measured as the film thickness. The measurement of the film thickness unevenness is determined from the measurement result of the film thickness at each position of the measured object.

When a contact type displacement detector is used, first, when an object to be measured in a state of a lower ground surface before film coating is placed on a surface plate or a moving table and the object to be measured is moved. Measure the displacement. Next, a change in the surface of the film is measured in the same manner after the film is formed on the base surface. The film thickness unevenness is measured by obtaining a change in the film thickness with respect to the shape of the base surface from the two measurement results.

When a dimension measuring device is used, the state of the base surface and the dimensions after film formation are measured at a plurality of positions at the same position, and the film thickness unevenness is measured by obtaining a dimensional change before and after the film formation. .

In some cases, a non-contact type displacement detector is used to measure the displacement of the object to be measured, as shown in FIG. That is, in FIG. 5, the object to be measured W "is placed on a measurement table 2" which is provided on a base 1 "and is movable in a predetermined direction, and two stands which stand on the base 1" at predetermined intervals. Non-contact displacement gauges 22 are provided on one of 20, 21.
On the other hand, an eddy current sensor 8 "and a reflector 23 are suspended on an arm 4" via a spring 15. Note that the reflection plate 23 is disposed so as to be located below the non-contact sensor 22.

[0009]

According to the above-described measuring methods, in the measurement of the film thickness unevenness of the coating film, the relationship between the under ground of the film and the film thickness cannot be measured simultaneously. Therefore, in many cases, these relationships are usually obtained by measuring the state of the ground under the film and the state after the film is applied, and comparing the measured results. In this case, it is difficult to accurately match the measurement position on the ground under the film with the measurement position after the film is applied, so that it is difficult to obtain a correct value.

In addition, since it is necessary to perform the measurement before and after the film thickness, and different measuring instruments may be used for each measurement, the measurement time and the measurement cost are not preferable.

When a non-contact type displacement detector is used, the measurement range is narrower than that of a contact type displacement detector, and when the workpiece W has a curved surface, the measuring device becomes complicated.

Since the present invention has been made based on these circumstances, it is possible to measure the lower ground surface and the film-forming surface of an object to be measured at the same time without separately measuring them, thereby achieving a quick and accurate film thickness and film thickness. An object of the present invention is to provide a method and an apparatus for measuring unevenness.

[0013]

According to the present invention, there is provided a method for measuring a change in film thickness of a non-conductive film formed on a surface of a conductor, wherein the film thickness is measured by an eddy current sensor, and the change in film thickness is measured by the eddy current sensor. There is provided a method for measuring a change in film thickness, characterized in that it is calculated based on a measurement result of a contact type displacement measuring device scanned simultaneously with an eddy current sensor.

According to the present invention, in the method for measuring the change in the thickness of the non-conductive film formed on the surface of the conductor, the thickness is measured by an eddy current sensor, and the change in the thickness is common to the eddy current sensor. And measuring the change in film thickness, based on a measurement result of a contact displacement measuring device that operates using the measurement terminal.

According to the present invention, there is provided a method for measuring a change in film thickness, wherein the non-conductive film is a Teflon film coated on the surface of an aluminum roller. Further, according to the present invention, there is provided a film having a measurement table on which a measurement object having a non-conductive film formed on a surface of a conductor is placed, and a measurement unit provided to be scannable relative to the measurement table. In the thickness change measuring device, the measuring unit measures an amount of displacement of the eddy current sensor while the eddy current sensor measures the film thickness by contacting the surface of the non-conductive film and measures the film thickness. And a contact-type displacement detector for detecting the change in film thickness.

According to the present invention, the eddy current sensor and the displacement detector operate using a common measurement terminal, and a pressure is applied to the measurement terminal by a spring of the displacement detector. Measuring device for measuring the change in film thickness.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a film thickness and film thickness unevenness measuring apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram showing the operation of the film thickness and film thickness unevenness measuring apparatus according to the embodiment of the present invention. FIG.

The test object W has a non-conductive thin film as a test film W2 formed on the surface of a base body W1 formed of a metal as a conductor. The object to be measured W is placed and fixed at a predetermined position on a measurement table 2 provided on the base 1. The measurement table 2 is slidably provided in the horizontal direction with respect to the base 1 by a driving device (not shown).

A stand 3 is provided at one end of the base 1. The stand 3 is provided with an arm 4 extending in a right angle direction. This arm 4 holds a contact type displacement detector 5 at the tip.

The contact type displacement detector 5 has a detector main body 5a provided at an upper part, a fixing jig 6 guided at a lower part by a linear guide structure, and a spring 15 adjusted to a predetermined tension.
Suspended by. Therefore, the fixing jig 6 has a structure that can be displaced only in the vertical direction with a stroke of about 10 mm.

The fixing jig 6 is made of a lightweight material such as aluminum, and has a measurement terminal 8 of the eddy current sensor 7 at one end. The measurement terminal 8 of the eddy current sensor 7 extends vertically downward from the fixing jig 6. doing. As a result, the measurement terminal 8 always applies a predetermined measurement pressure to the measured object W.

The contact type displacement detector 5 and the eddy current sensor 7 are connected to a control device 9. The control device 9 includes a control unit 10 that controls the entire device, and a measurement data processing unit 11 that checks a mutual relationship between respective measurement data of the contact displacement detector 5 and the eddy current sensor 7. .

The measurement data processing unit 11 has a function of synchronizing and acquiring measurement data from the contact type displacement detector 5 and the eddy current sensor 7, and a function based on the position data of the contact type displacement detector 5 based on the acquired measurement data. It has a function to correspond the measurement data of the eddy current sensor 7 to this.

That is, based on the measurement data obtained by scanning the surface of the film to be measured W2 with the measuring terminal 8, the change in the film thickness with respect to the shape of the surface of the film to be measured W2 is calculated, so that the film thickness unevenness is obtained. It has been calculated.

The operation of the above device will be described below.

First, the object to be measured W is placed at a predetermined position on the measurement table 2 on the base 1 and fixed by fixing means such as a magnet chuck (not shown). Next, the position of the part to be measured of the object to be measured W and the position of the measuring terminal 8 are matched. In this matching method, the arm 4 engaged with the stand 3 is rotated by a predetermined angle in the Y direction and set to a predetermined position. In the X direction, the measurement table 2 on the base 1 is moved by a predetermined amount and set at a predetermined position. In this state, the contact type displacement detector 5 is gently lowered by a vertical driving mechanism (not shown) provided on the stand 3. Due to this lowering, the measurement terminal 8 of the eddy current sensor 7 integrally mounted on the contact type displacement detector 5 comes into contact with the surface of the measurement target film W2 of the measurement target. Next, in the X direction, the measurement table 2 on the base 1 is moved by a predetermined amount and set to a predetermined position, and the measurement start position is positioned.

Next, the measurement table 2 starts scanning at a predetermined speed in response to a command from the control unit 10. By this scanning, measurement data is sequentially input from the eddy current sensor 7 and the contact type displacement detector 5 to the measurement data processing unit 11.

At this time, in the eddy current sensor 7, since the measuring terminal 8 applies the measurement pressure from the contact type displacement detector 5 and follows the film surface precisely, the film thickness can always be measured accurately. I can do it.

Since the contact type displacement detector 5 has the measurement terminal 8 also serving as the measurement terminal 8 of the eddy current sensor 7, the contact type displacement detector 5 always follows the film thickness surface with a predetermined measurement pressure, so that the film surface can be accurately measured. Measure the displacement.

The measurement data input from the contact type displacement detector 5 and the eddy current sensor 7 input to the measurement data processing unit 11 is based on the position data of the contact type displacement detector 5 as a reference. The relationship between the shape of the ground surface and the film thickness can be obtained by comparing and correlating the measurement data of the displacement amount obtained from the sensor 7 and the displacement amount from the contact displacement detector 5 with the data from the eddy current sensor 7. I can do it.

That is, as shown in FIGS. 3 (a) to 3 (d), the eddy current sensor 7 measures
The data (A) of FIG. 3 is obtained, and the data (B) of FIG. Therefore, FIG.
By overlaying these two data (BA) as in (d), the film thickness unevenness can be accurately detected.

Therefore, by performing the above-described measuring method using the film thickness and film thickness nonuniformity measuring device, it is possible to obtain the film thickness and the film thickness nonuniformity simultaneously and accurately with a single measurement.

Next, another embodiment of the present invention will be described with reference to FIG.

In the above-described embodiment, the thickness of the object to be measured W is measured with the film to be measured W2 formed on the surface of the planar base body W2. The case where the measurement object W is cylindrical will be described. That is,
In this embodiment, the film to be measured W2 is a cylindrical substrate W
It is formed in a cylindrical shape on the surface of 2 '.

Since the basic configuration is the same as that of the above-described embodiment, the description of the same parts will be omitted. However, in the above-described embodiment, the position of the film to be measured is detected by a straight line because the film to be measured W is flat, but in this embodiment, since the film to be measured W2 'is cylindrical, the cylindrical body is rotated. Then, the film thickness and the displacement amount are simultaneously measured by the position detection for each rotation.

That is, the measurement table 2 'provided on the base 1' is formed in a disk shape and is rotatable around a rotation axis. A contact type displacement detector 5 'holding an eddy current sensor 7 having a measuring terminal 8' movable along the radial direction of the rotating shaft is provided on an upright stand 3 '. The stand 3 'is placed on the XY table 12, and the operating direction of the measuring terminal 8' is adjusted so as to always face the rotation center of the measuring table 2 '.

When measuring a cylindrical film W2 'to be measured by this device, first, the center of rotation of the cylindrical body as the object W to be measured is made to exactly coincide with the center of rotation of the measuring table 2'. The center of rotation of the cylindrical body is the center of rotation of the conductor forming the cylindrical body.

Next, the XY table 12 on which the stand 3 'is placed is gently operated to adjust the measurement terminal 8' so as to contact the film W2 'to be measured. In this state, the measurement table 2 'is gently rotated to set the measurement start position.
Thereafter, the measurement is started by a command from the control unit 10 as in the above-described embodiment, and each measurement data is input to the measurement data processing unit 11 to obtain the measurement results of the film thickness and the film thickness unevenness.

In these embodiments, the measuring terminal 8 and the spring 15 are provided at different positions in the same direction, but are provided coaxially at the same position to support the measuring terminal 8 'and the spring 15'. The distortion of the fixing jig 6 does not affect the measurement result.

[0041]

As described above, according to the present invention, the eddy current sensor for measuring the film thickness of the object to be measured and the contact type displacement measuring device for measuring the amount of displacement of the film thickness are simultaneously scanned to obtain the film. The thickness data and the displacement data of the film thickness are simultaneously obtained for each measurement position.

Therefore, by comparing and comparing the measured data, it is possible to grasp the fluctuation data of the base surface and the fluctuation data of the film surface, and to quickly and accurately measure the film thickness and the film thickness unevenness in one measurement. Can be measured.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an entire apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating an operation of the device according to the embodiment of the present invention.

FIG. 3A is a schematic diagram showing a main part of a measurement principle according to an embodiment of the present invention. (B) A graph showing output data from the eddy current sensor according to the embodiment of the present invention. (C) A graph showing output data from the contact displacement detector according to the embodiment of the present invention. (D) A graph combining output data from the eddy current sensor and output data from the contact displacement detector according to the embodiment of the present invention.

FIG. 4 is a schematic diagram of the entire apparatus showing another embodiment of the present invention.

FIG. 5 is a schematic diagram using a non-contact sensor as a displacement detector.

[Explanation of symbols]

1, 1 '... base, 2', measurement table, 3, 3 '...
Stand, 5, 5 '... contact type displacement detector, 7, 7' ... eddy current sensor, 8, 8 '... measuring terminal, 9 ... control device, 11
... Measurement data processing unit, 15 ... Spring, W, W '... Measurement object, W1, W1' ... Substrate, W2, W2 '... Measurement film

Claims (5)

[Claims] 1. A method for measuring a change in film thickness of a non-conductive film formed on a surface of a conductor, wherein the film thickness is measured by an eddy current sensor, and the change in film thickness is scanned simultaneously with the eddy current sensor. A method for measuring a change in film thickness, which is calculated based on a measurement result of a displacement measuring device. 2. A method for measuring a change in film thickness of a non-conductive film formed on a surface of a conductor, wherein the film thickness is measured with an eddy current sensor, and the change in film thickness is measured using a common measurement terminal with the eddy current sensor. A method for measuring a change in film thickness, characterized in that it is calculated on the basis of a measurement result of a contact displacement measuring device that operates by a manual operation. 3. The method according to claim 1, wherein the non-conductive film is a Teflon film coated on a surface of an aluminum roller. 4. A film thickness change comprising a measurement table on which an object to be measured having a non-conductive film formed on a surface of a conductor is placed, and a measurement section provided to be scannable relative to the measurement table. In the measuring device, the measuring unit detects an amount of displacement of the eddy current sensor while the eddy current sensor measures the film thickness by contacting the surface of the non-conductive film and measures the film thickness. An apparatus for measuring a change in film thickness, comprising: a contact-type displacement detector. 5. The apparatus according to claim 4, wherein the eddy current sensor and the displacement detector operate using a common measurement terminal, and apply pressure to the measurement terminal by a spring included in the displacement detector. Measurement device for film thickness change.