TWI227319B - Method of measuring film thickness and microwave measuring unit - Google Patents

Abstract

A method of measuring film thickness and microwave measuring unit are provided. The method comprises providing an object and then measuring a needful time, t0, which a first signal of microwave region transmitting from a measuring point to the object surfaces. An object under test (OUT) that an object being took place a surface treatment is provided, wherein there is a surface treatment film on a surface of the object. A needful time, t1, which a second signal of microwave region transmitting from a measuring point to the OUT surfaces is measured, wherein the second signal is the same as the first signal. A film thickness of the surface treatment film of the OUT, d, is then calculated by the wavelength of the first signal, lambda, and time lag, t0-t1, wherein a calculating formula is d=lambda(t0-t1). Because of emission, reflection, and receiving of the signal and utilization of microwave region, it can easily and accurately measure thinner film thickness.

Description

1227319 _ Case No. 92115651 V. Description of the invention (1) 93. 10. The technical field to which the invention belongs in January 2015 The present invention relates to a film thickness measurement method and a microwave measurement device, and more particularly to a film thickness measurement method and a microwave measurement device. Measurement method and microwave measurement equipment capable of accurately measuring non-planar film thickness. Prior art

At present, the development of 3 C products is gradually diversified and the appearance is lively with the needs of customers, and different coating, sputtering, transfer, plating, and even impregnation technologies are given to the shell. These technologies are often difficult to control the film thickness of the shell, so it is easy to increase product variability. This is not that the product itself has many problems, but that the distribution of film thickness cannot be accurately grasped in order to provide customer design guidelines. 5 Above micron, this corresponds to the thickness of a layer of paint.

For the measurement of film thickness or film thickness distribution, it is common to obtain the film thickness or film thickness distribution using the so-called single-point destruction or single-point non-destructive measurement and the ultrasonic C-scan method. The biggest problem is that as far as single-point damage or single-point non-destructive measurement is concerned, little data is obtained, so it is impossible to provide accurate information, and the position of the measurement point itself is greatly variably. For the ultrasonic C-scan method, it can only measure a minimum film thickness of 15 micrometers or more (the deviation value is currently known to about ± 1 micrometer), so it is difficult to accurately measure a thin film thickness. And a big problem occurred, even more so 1227319 _ case number 92115651_ year month day _ «V. Description of the invention (2) The quantity and accuracy of the method can be measured and measured, thick and thick film type. A thin cloth is provided for comparison. The thickness of the ground is the precise and clear surface of the test film and the light weight of the body. It can be faced with this method. Thick square film »MJ JnJ It is thick and thin in the film species layer. The surface is provided for the purpose of the surface. The test is to be performed until the light is released. It is equipped with a measurement and absorption method. One of the thick mask sheet species at the measurement point is for measurement and measurement. It is measured and measured to avoid the need to avoid light. If the device is broken, the device is broken, the device is clear, the method of measuring the thickness of the film, and the method of measuring the thickness of the film. It is easy to supply and withdraw. When the difference between the values is different, the device will receive the iiuu # message. Make the sound impactable, and the external receiver will measure a certain amount of thick film wave micro-micro-a measurement of the long-distance wave wave measurement ΓΤΠ, which is related to the substance and a description of the evidence. The method of extracting the donor, after the middle, then, the time-honored space between the body and the object, the surface and the surface of the object should be measured to the point, and the amount of the object should be measured from the number 1 to 1 IHd. . Duan Yu. The sample in the wave is slightly different. The source of the long-distance wave is the long-term wave. The source of the wave is required. It is measured by the following table. The object to be measured should be measured at the front layer, and the number should be measured on the meter. The number of the equipment used is λ U, d, and the thickness of the film is JnJ £. For the physical calculation of the formula in the formula, the estimated value of the table J is a fake. The step j shot the tiger against its flf, and the law of the square shot of the law I 'will be the thickness of the skin after 0 ^ ^ 置 一 装 # * U 达提 ^ and then the U-shot broadcast sends the middle wave Micro, one side

Page 8 1227319 Case No. 92115651 ία Month Revision V. Description of the invention (3) After receiving the first reflection signal by using the microwave transmitting / receiving device to obtain the% of time required for the signal to reach the sample from the microwave transmitting / receiving device. Then, the microwave transmitting / receiving device is used to transmit a signal with the same wavelength to a sample that has been surface-treated and has a surface-treated layer, wherein a second reflection signal is reflected after the signal reaches the surface-treated layer. Subsequently, the microwave reflection / receiver is used to receive the second reflection signal to obtain the time t i required for the signal to reach the surface treatment layer from the microwave transmission / reception device. Then, the film thickness d of the surface treatment layer of the sample is estimated by using the difference between the wavelength λ and the reflection receiving time (tQ-h), where the estimation formula is d = A (tQ-h). In addition, the present invention also proposes a microwave measuring device, which is suitable for measuring a test object having a non-planar surface, and then estimates the difference in surface thickness of the test object before and after the surface treatment according to the obtained data. The microwave measuring device includes at least a microwave transmitting / receiving device and a processing device, wherein the microwave transmitting / receiving device has a plurality of transmitters and a plurality of receivers arranged in an array. The microwave transmitting / receiving device is located above the object under test. The transmitter is used to transmit signals in the microwave range to the surface of the object under test, and the receiver is used to receive the signal through the surface of the object under test The signal emitted by the transmitter. The processing device is connected to the microwave transmitting / receiving device to measure the time required for the signal to reach the object under test based on the difference between the transmitting / receiving time of the signal. Because the present invention transmits, reflects, and receives signals, and sets the microwave band in the short-wave high-frequency range, it can easily and accurately measure thinner film thicknesses. In order to make the above and other objects, features, and advantages of the present invention more comprehensible, preferred embodiments are described below with reference to the accompanying drawings.

Page 9 1227319 __ Case No. 92115651_ ± _9 _ V. Description of the invention (4) The detailed description is as follows:

Figures 1A and 1B are schematic diagrams illustrating the principle of film thickness measurement according to the present invention. Please refer to Figure 1A. Assuming that the thickness of the surface treatment layer on an object 100 with an irregular plane is to be measured, it can be provided first-object 100, which has not been surface-treated and is mainly used as a background. Measurement of values. Then, a transmitter 104 transmits a signal 104 to an unsurfaced object 100, and sets the wavelength range of the signal 104 to the short-wave and high-frequency microwave band, such as the wavelength of the signal 104 〇 · 〇 1 ~ 10 cm, the frequency is between 3 G Η z ~ 3 0 0 0 G Η z. When the signal 104 reaches the surface of the object 100, a reflected signal 106 will be reflected. At this time, a receiver 1 〇 2 b can be used to receive this reflected signal 10 6, so the signal with a wavelength range in the microwave band can be measured. 〇 4 from the transmitter 1 0 2 a (that is, the measurement point) to the object 1 〇0 surface required time. In addition, when the transmitter 10 2 a is used to transmit the signal 1 〇 04 to the object 100, the object 1 0 can be fixed first, and then the transmitter 1 0 2 a can be moved in a moving direction 1 08 relative to the object 1 0 0. mobile. After that, please refer to Figure 1B. Lifu has the same principle as Figure 1A.

Measure an object 100 (that is, a test object 120) that has been surface-treated and has a surface treatment layer 110, where the test object 120 is, for example, subjected to mouth coating, money plating, transfer printing, A surface treatment layer 1 1 0 is formed on the surface of the object 100 by plating or impregnation. The measurement principle here is the same as that in Figure 1A. The transmitter 1 0 2 a emits a signal 10 4 to the object to be measured 120. The wavelength of the signal 1 04 must be the same as that used in Figure 1 A. The same. In addition, when using the transmitter 丨 〇2 a to transmit the signal 104 to the test object 丨 2 〇, the test object 1 2 〇 can be fixed first, and then the transmitter 丨 〇 2 a Move in a direction of 1.08. when

Page 10 1227319 _ Case No. 92115B51_ Year Month and Day _ V. Description of the invention (5) When the signal 1 0 4 reaches the surface of the object 1 2 0 to be measured, it will reflect another reflection signal 1 from the surface of the surface treatment layer 1 1 0 〇6 a. At this time, the receiver 1 0 2 b can be used to receive this reflected signal 1 0 6 a, so the measured signal 1 0 4 in the microwave range is measured from the transmitter 1 0 2 a to the surface of the object to be measured. The time required b. Therefore, the wavelength of the signal 104 can be used; the time difference (tG-I) between I and the reflection receiving time (tG-I) can be used to estimate the film thickness d of the surface treatment layer 110 of the object 100. The estimation formula is as follows:

In addition, by measuring the overall film thickness distribution of the surface treatment layer object 110 of the object 100 with microwave measurement, in addition to using the one-by-one receiving characteristics of the aforementioned signals, it can also be performed by Fast Fourier Transform (Fast Fourier Transform, for short) FFT). According to the above principle, the present invention can be applied to the following embodiments. First Embodiment Figure. Please send the surface number of the device, and 3GHz ~ the emitted wave for the sample microwave axis. The first inverse 2 diagram is a film thickness measurement step t τ d according to the first embodiment of the present invention. In step 2 0 ', a microwave transmission / bucket is used. Without

The wavelength of the signal; I, for example, the second reflection a after the second reflection flood between 3 0 0 0 GHz). This 10.01 ~ 10 cm (frequency is ^ long and long signal to the sample when using the microwave transmitting / receiving device: When the microwave transmitting / receiving surface, the sample can be fixed before the phase transmitting / receiving device such as It is set to move in a moving direction again. After that, in step 202, the mobile radio signals containing multiple microwave transmitters are received to obtain the information / received by the microwave transmitting / receiving device or the arrival book from the microwave transmitting / receiving device.

Page 11 1227319

: I < 3. LU. 1 D _ case number 92115651_ year month day __ 5. Description of the invention (6) The time required for the product tD. Then, please continue to refer to FIG. 2. In step 204, the microwave transmitting / receiving device is used to transmit a signal with a wavelength of λ to a sample that has undergone surface treatment and has a surface treatment layer, and the signal reaches the surface treatment layer. After that, a second reflection signal is reflected, and the wavelength of the signal transmitted here needs to be the same as the wavelength of the signal transmitted in step 200. In addition, the surface treatment of the sample includes spray coating, low-plating, transfer printing, electric ore mining or impregnation. In addition, when using the microwave transmitting / receiving device to transmit a signal to the surface of the surface treatment layer, the sample can be fixed first, and then the microwave transmitting / receiving device can be moved in a moving direction relative to the sample. The microwave transmitting / receiving device contains The axis of the microwave transmitter. Next, in step 206, the microwave reflection / reception device is used to receive the second reflection signal to obtain the time t i required for the signal to reach the surface treatment layer from the microwave transmission / reception device. Please refer to FIG. 2 again, and perform step 208, using the wavelength; I and the reflection receiving time difference (tQ- td to estimate the film thickness d of the surface treatment layer of the sample, where the estimation formula is d = λ (tQ- D. In addition, the overall film thickness distribution calculation of the surface treatment layer of the sample measured by microwave measurement can be obtained through fast Fourier transform in addition to the one-by-one reception characteristics of the signal. The following are two examples of applying the present invention : 1 · Using a microwave transmitting / receiving device with a wavelength of 3 G 波长 z (wavelength equivalent to 10 cm or 100 micrometers), using the method of the present invention to measure a coating with an estimated film thickness of 10 micrometers, then As long as the required time difference is 0.1 ms and the relative accuracy of the microwave transmitter / receiver is within 0.1 ms, the overall film thickness distribution on the curved surface can be obtained during the synchronous scanning process.

1227319 on page 12 _Case No. 92115651_Year Month Date__ V. Description of the invention (7) 2. A microwave transmitting / receiving device with a wavelength of 3 0 0 0 GHz (wavelength equivalent to 0.01 cm or 100 micrometers), using this The method of the invention measures a coating with an estimated film thickness of 10 microns, so long as the required time difference is 100 ms, and the relative accuracy of the microwave transmitter and receiver is within 10 ms, then the synchronous scanning process can be used. The overall film thickness distribution on the curved surface is obtained. It can be known from the above examples that the present invention uses signals in the microwave range for measurement, and can be used with existing receivers to easily obtain the film thickness of the object to be measured. In addition, in order to illustrate the advantages of the present invention, please refer to the table below. The range of wavelengths (cm), frequency (Hz), energy (eV), wireless electromagnetic waves > 10 < 3xl09, < 105 microwaves 10 to 0.01 3xlOP to 3xl 〇12 10 · 5 ～ 0.01 Infrared ο · οι ～ 7xio.5 3xl〇12 ～ 4.3xl〇14 0.01 ～ 2 · Visible light 7X1CT5 ～ 4X1CT5 4.3M014 ～ 7.5X1014 2 ～ 3 Ultraviolet light 4x100.5 ～ 10.7 7.5xl〇 14 ～ 3xl〇17 3 ～ 103 X-ray ίο · 7 ～ 10 · 9 3xl〇17 ～ 3xl〇19 103 ～ ίο5 Gamma ray < 10 · 9 > 3x1019 > ισ5

Table 1 shows the general signal radiation spectrum. According to Table 1, it can be known that the main reason for not using X-rays and gamma rays in the present invention is that the energy entrained by them is very large, which may easily cause problems such as genetic diseases of the operator. If you choose UV,

Page 13 1227319 _ Case No. 92115651 Car month 9 _ ^ __ V. Description of the invention (8) Although visible energy, although its energy is not high, it is easy to damage the surface treatment layer. Infrared rays are absorbed by the molecules of the surface treatment layer by means of rotation, vibration and shear harmonic motion. As for the wireless signal, the wavelength is too long. At present, it is not easy for the receiver to measure the time difference and it is susceptible to external influences. In summary, the present invention uses a signal in the microwave range to measure the film thickness, which can not only easily and accurately measure a thinner film thickness, but also avoid the aforementioned disadvantages. Second Embodiment The present invention also proposes a microwave measurement device, which can be used to achieve the film thickness measurement method of the present invention, as shown in FIG. 3. Fig. 3 is a schematic diagram of a microwave measuring device according to a second embodiment of the present invention. Referring to FIG. 3, the microwave measuring device 300 of the present invention is suitable for measuring an object to be measured 3 on a non-planar surface of the tool. The microwave measuring device 300 includes a microwave transmitting / receiving device 3o. 2 and a processing device 308. The microwave transmitting / receiving device 3 0 2 is located above the test object 3 1 0. The microwave transmitting / receiving device 3 0 2 has a plurality of transmitters 3 04 and a plurality of receivers 3 0 6 arranged in an array. The receiver 3 〇4 is used to transmit the signal in the wavelength range of the microwave band to the surface of the DUT 3 1 〇, and the receiver 3 〇6 is used to reflect the surface of the DUT 3 1 0 to receive the transmitter 3 〇 4 emitted signals. The processing device 3 0 8 is connected to the microwave transmitting / receiving device 3 02 and measures the time required between the signal and the object to be measured 3 based on the difference between the transmitting / receiving time of the f signal. In addition, the device 300 of the present invention may further include a moving shaft (not shown), a transmitter 3 04 and / or a receiver 306 connected to the microwave transmitting / receiving device 3 02, for simultaneously moving the transmitter 3 〇4 and / or receiver 3 06. In addition, the device 300 of the present invention can also be added with a positioning device (not

Page 14 1227319 _ Case No. 92115651 V. Description of the invention (9) 9: ι Αα ί 〇 _ _ (shown), used to locate the test object 3 1 0. In summary, the present invention is characterized by transmitting, reflecting, and receiving signals, and setting its wavelength range in the microwave range, so that thinner film thicknesses can be easily and accurately measured. In addition, the present invention proposes a microwave transmitter with an array, which can more effectively measure curved objects to be measured. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and retouches without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be determined by the scope of the attached patent application.

Page 15 1227319 _Case No. 92115651_ 年月 日 _iti_ Schematic illustrations Figures 1A and 1B are schematic diagrams of the principle of film thickness measurement according to the present invention; Figure 2 is a diagram according to the present invention The film thickness measurement step diagram of the first embodiment, and FIG. 3 are schematic diagrams of a microwave measurement device according to a second embodiment of the present invention. Description of the diagrams 1 0 0: Object 10 2a, 3 0 4 ·· Transmitter 10 2b, 3 0 6: Receiver 1 0 4: Signal 1 0 6, 1 0 6 a: Reflected signal 1 0 8: Movement direction 1 1 0 ·· Surface treatment layer 1 2 0, 3 1 0: object to be measured 2 0 0: using a microwave transmitting / receiving device to emit wavelength; a signal of I to a sample surface, and the sample is not shown Surface processing, where a first reflected signal is reflected after the signal reaches the sample

2 0 2: Use the microwave transmitting / receiving device to receive the first reflection signal to obtain the time required for the signal to reach the sample from the microwave transmitting / receiving device tQ 2 0 4: Use the microwave transmitting / receiving device to transmit a signal with a wavelength of λ to A sample having a surface treatment layer subjected to a surface treatment, in which a signal reflects a second reflection signal after reaching the surface treatment layer 2 06: the second reflection signal is received by a microwave transmitting / receiving device, and

Page 16 1227319

Page 17

Claims (1)

1227319 _Case No. 92115651_ 年月 日 _Iti_ VI. Application for Patent Scope 1. A method for measuring film thickness, including: providing an object; measuring a signal in the microwave range from a measurement point to the surface of the object Required time tQ; provide a test object, the test object is a surface-treated object, wherein the object has a surface treatment layer; the signal with a measurement wavelength range in the microwave range arrives from the measurement point The time ti required for the surface of the object to be measured; and the difference between the wavelength λ and the time of the signal (tQ- to estimate the film thickness d of the surface treatment layer of the object, where the estimation formula is dzACtf ti) ° 2. The film thickness measurement method according to item 1 of the patent scope, wherein the wavelength of the signal is between 0.01 and 10 cm, and the frequency of the signal is between 3 G Η z and 3 0 0 0 G Η ζ . 3. The film thickness measurement method according to item 1 of the scope of patent application, wherein the step of providing the object to be tested includes spraying, sputtering, transferring, plating or impregnating the object to form the surface of the object This surface treatment layer. 4. The film thickness measurement method according to item 1 of the scope of patent application, wherein the object includes an irregular plane. 5. The film thickness measurement method as described in item 1 of the scope of patent application, which further comprises calculating the overall film thickness distribution using a fast Fourier transform. 6. A film thickness measurement method, suitable for measuring a sample requiring a surface treatment, the steps include: using a microwave transmitting / receiving device to transmit a signal of wavelength λ to a Page 18 1227319 _Case No. 92115651_Year Month Date _ «_ VI. Patent application sample surface, where the signal will reflect a first reflection signal after reaching the sample; use the microwave transmitter / receiver to receive the first reflection Signal to obtain the time required for the signal to reach the sample from the microwave transmitting / receiving device, and to use the microwave transmitting / receiving device to emit the signal having a wavelength of λ until the surface treatment has been performed to have a surface treatment layer The sample, wherein the signal reflects a second reflection signal after reaching the surface treatment layer; the second reflection signal is received by the microwave transmitting / receiving device to obtain the signal reaching the surface from the microwave transmitting / receiving device The time t 丨 required to process the layered object; and the film thickness d of the surface treated layered object of the sample was estimated by using the difference between the wavelength λ and the reflection receiving time (h), where the estimation formula was d = A (t〇-1 7. The film thickness measurement method according to item 6 of the scope of patent application, wherein the wavelength of the signal is between 100 μm and 100 μm and the frequency of the signal is 3 G Η z 3 0 0 0 G Η z. 4 8. The film thickness measurement method according to item 6 of the patent application scope, wherein the step of transmitting the signal of wavelength λ to the surface of the sample using the microwave transmitting / receiving device, The method includes: fixing the sample; and moving the microwave transmitting / receiving device relative to the sample. 9 · The film thickness measurement method according to item 8 of the patent application scope, wherein the microwave transmitting / receiving device includes a plurality of microwave transmitting devices. Device movement Page 19 1227319 Case No. 92115651 93. 10. ± _Ά Amendment VI. Patent Application Axis 0 1 0. The film thickness measurement method described in Item 6 of the Patent Application Scope, where the surface treatment includes spray coating, sputtering , Transfer, plating or impregnation. 1 1. The film thickness measurement method according to item 6 of the scope of patent application, wherein the object includes an irregular plane. 12. The method for measuring the film thickness as described in item 6 of the scope of the patent application, which further includes calculating the overall film thickness distribution using a fast Fourier transform. 1 3. A microwave measuring device suitable for measuring an object to be measured on a non-planar surface of the tool. The microwave measuring device includes at least: a microwave transmitting / receiving device located above the object to be measured, wherein the microwave emission The receiving device has a plurality of transmitters and a plurality of receivers arranged in an array, wherein the transmitters are used to transmit a plurality of signals in a microwave range to the surface of the object to be measured; the receivers are used to Receiving the signals emitted by the transmitters through the reflection of the surface of the object to be measured; and a processing device connected to the microwave transmitting 7 receiving device, and measuring the signals according to the transmission / reception time difference of the signals The time required for these signals to reach the DUT. 14. The microwave measuring device as described in item 13 of the scope of the patent application, further comprising a moving shaft connected to the transmitters of the microwave transmitting / receiving device for simultaneously moving the transmitters. 15. The microwave measuring device as described in item 13 of the scope of the patent application, which further includes a moving shaft connected to the microwave transmitting / receiving devices. Page 20 1227319 9ό. I _ case number 92115651 _ year month day __ Sixth, the scope of the patent application, used to move these receivers at the same time. 16. The microwave measuring device according to item 13 of the scope of patent application, further comprising a positioning device for positioning the object to be measured. 17. The microwave measuring device according to item 13 of the scope of patent application, wherein the wavelengths of these signals are between 100 microns and 100 micrometers, and the frequencies of these signals are between 3GHz and 3000GHz. between.