JP2006210415A - Method and apparatus for inspecting component, and manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a method and apparatus for inspecting a component for managing performance and deterioration degree for each component by detecting unique impedance with high sensitivity and high accuracy, and by quantitatively comparing the difference between components. <P>SOLUTION: A component (1) to be measured is closely stuck on a lower electrode (3) and an upper electrode (4) in electromagnetic shields (2, 6). The lower electrode and the shields are grounded, the upper electrode is insulated from the shields by an insulator (5), frequency is swept from a network analyzer (8), and a high-frequency signal is supplied to the upper electrode. Accordingly, its impedance is measured. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a component inspection method for measuring electrical characteristics such as impedance or frequency characteristics of a component, a component inspection apparatus, and a manufacturing apparatus incorporating the inspection apparatus.

  In the manufacturing process of semiconductor elements and liquid crystal displays (LCD), there are many processes using plasma such as etching, thin film formation (film formation), and sputtering.

  In a plasma processing apparatus that performs various processes using such plasma, it is important to maintain a constant process performance by maintaining a constant state of the apparatus in order to produce a product with a high yield. It is. In addition, since a plurality of plasma processing apparatuses are used in parallel during mass production of the product, it is necessary to maintain the apparatus state so as not to vary between the plurality of plasma processing apparatuses.

  On the other hand, it is difficult to directly detect changes in apparatus state over time and apparatus state variations among plasma processing apparatuses. Conventionally, the process performance has been kept constant by the following procedure. That is, it is determined that the apparatus state has changed when an abnormality occurs in the product due to a change in process performance. According to this abnormality determination result, maintenance such as cleaning of the plasma processing apparatus or replacement of parts is performed, and the apparatus state is reset. As another method, the time when the process performance changes empirically is predicted, and the plasma processing is regularly maintained.

  Instead of such a conventional artificial method, a method for detecting an electrical change in a high-frequency power supply system that supplies high-frequency power to a processing chamber and evaluating the apparatus state and process performance of the plasma processing apparatus is, for example, Patent Document 1 (Japanese Patent Laid-Open No. 11-112440) discloses this.

  In the configuration disclosed in Patent Document 1, a monitor is connected to a discharge electrode disposed on a table in a reaction chamber. As an electrical physical quantity when plasma is generated in the reaction chamber, the monitor calculates the total impedance of the impedance of the power supply system of the discharge electrode, the impedance of each of the discharge electrode, the table and the reaction chamber, and the impedance of the generated plasma. Measure. The monitor is supplied with high-frequency power from a high-frequency power supply via a matching circuit. Based on the impedance information measured by the monitor, the state and process performance of the plasma processing apparatus are evaluated using, for example, a computer.

  As a specific measuring method, in this reaction chamber, a wafer is placed on a discharge electrode on a table, and a reactive gas for performing processing such as etching or film formation is introduced. Plasma is generated by exciting the reactive gas from the high frequency power supplied to the discharge electrode. The plasma impedance is measured in the plasma excited state. A state similar to that in the actual process is realized, it is determined whether or not the generated plasma is normally generated, and the state and process performance of the plasma processing apparatus are evaluated.

  A configuration for evaluating the state of the plasma processing apparatus and the process performance by measuring the impedance inherent to the apparatus determined by the geometric configuration of the plasma processing apparatus in the absence of plasma is disclosed in Patent Document 2 (Patent Document 2). No. 2003-282542). In the configuration disclosed in Patent Document 2, high-frequency power from a high-frequency power source is supplied to the discharge electrode in such a magnitude that plasma is not generated in the reaction chamber, and the high-frequency current flowing at that time is detected. . The detected high-frequency current is compared with a reference high-frequency current, and the process performance of the plasma processing apparatus is evaluated as normal or abnormal according to the comparison result.

  At the time of evaluation, the high-frequency characteristics of the object to be measured are measured by measuring the reflection coefficient and the transmission coefficient of the reaction chamber with respect to the characteristic impedance of the measurement system. As an equivalent circuit of the measurement system, a circuit composed of a series body of an inductance L and a resistance R of a power feeding system and parasitic capacitances C1 and C2 between the reaction chamber and the power feeding system is used. Capacitors C1 and C2 are respectively connected in parallel to both ends of the series body.

  The impedance Z is calculated from the reflection coefficient Γ based on the following equation.

Z = Z0 · (1 + Γ) / (1-Γ)
This calculation result is fitted to one of the above-mentioned LCR equivalent circuits of the device under test to determine the unknowns R, L, C1 and C2 of the equivalent circuit, and the device-specific impedance Z0 is detected.

  Moreover, in the ECR type plasma processing apparatus, a method of monitoring the plasma state by measuring the frequency dependence of plasma impedance is conventionally used. In this ECR type plasma processing apparatus, high-frequency power is supplied from a high-frequency power source to a stage for wafer placement using a directional coupler. Using this directional coupler, the reflected wave from the stage is measured without being affected by the input wave. By changing the frequency of the high frequency power supplied, the frequency characteristic of the plasma impedance is detected, and the apparatus state and the plasma state are detected.

  Further, instead of such a configuration for measuring the characteristic impedance of the entire processing apparatus, Patent Document 3 (Japanese Patent Laid-Open No. 2003-133404) describes an electrostatic chuck for holding an object to be processed in a vacuum chamber. A method aimed at evaluating performance is disclosed. In the configuration shown in Patent Document 3, one or more characteristics are measured before the electrostatic chuck is mounted in the vacuum chamber, and compared with the known characteristics of the reference chuck. Predict the chuck characteristics in the operating environment. In the method disclosed in Patent Document 3, a method of directly detecting a leakage current and impedance between internal currents of an electrostatic chuck with a probe is used.

In general, there is a measurement method using an LCR meter as a method for measuring the impedance specific to a component. When this LCR meter is used, the probe is brought into contact with both surfaces of the measurement target component, and the resistance component, inductance component, and capacitance component of the impedance between the probes are measured.
JP-A-11-112440 JP 2003-282542 A JP 2003-133404 A

  In the configuration shown in Patent Document 1, basically, the plasma impedance can be specified only by the power supply frequency of a high-frequency power source that supplies high-frequency power. There is a frequency band in which the impedance changes greatly with respect to changes in the apparatus state and process performance. However, in the configuration shown in Patent Document 1 described above, when the power supply frequency is deviated from the frequency band, the impedance change is small or hardly changed with respect to the change in the state of the process and the apparatus. Therefore, there arises a problem that accurate performance evaluation cannot be performed.

  Moreover, in the structure shown by patent document 1, when the change of an impedance is detected, the apparatus state can be judged as the whole plasma processing apparatus. However, when the device states are different, it is necessary to specify the factor (part). In an apparatus with a small number of parts, the factor location candidates can be separated and measured. However, in order to identify them, it is extremely difficult for an apparatus having a long time and a large number of parts. In particular, if there is an abnormality in a part (for example, a part such as a discharge electrode that greatly affects the process performance), even if the abnormality can be detected by impedance change, there is an abnormality in the part installed during maintenance Until the device is installed and started up, and then the impedance is measured, the abnormality cannot be detected, and the time until the device is started up after the parts are installed is wasted. Furthermore, it takes time to start up the apparatus again by exchanging parts, and the time required for maintenance becomes even longer.

  Further, in the configuration shown in Patent Document 2, although it is possible to determine the state of the apparatus by measuring the impedance inherent to the apparatus when no plasma is generated, the process itself cannot be directly evaluated. Further, like the configuration shown in Patent Document 1, the measurement frequency is also a measurement at the power supply frequency, and there may be a case where an impedance change cannot be detected, and even if a change in impedance is detected, In the case where the apparatus states are different, the same problem as the configuration of Patent Document 1 occurs in specifying the factor part.

  In the configuration disclosed in Patent Document 3, the performance of the electrostatic chuck is evaluated by detecting one or more electrical characteristics in advance before mounting the electrostatic chuck on the processing apparatus. Therefore, the actual device state and process cannot be determined directly.

  In addition, a leak current or impedance is detected using a probe, and the influence of the difference in the contact state of the probe on the measurement value cannot be ignored, and accurate measurement may not be possible.

  Moreover, when using an ECR type plasma processing apparatus, a directional coupler is used in the middle of the high-frequency power supply system, causing the following problems. (1) Subtle changes during measurement of the power supply system cause changes in the equipment state and process. (2) CVD (Chemical Vapor Deposition) equipment has a high power supply system and directional coupling. In these operating environments, measurement may not be performed using a directional coupler, and (3) there may be no space for installing the directional coupler in the feed system.

  Moreover, the problem that the measurement sensitivity of the plasma impedance may become dull depending on the apparatus may occur.

  In the configuration of the ECR type plasma processing apparatus, the state of the apparatus as a whole can be determined. However, if the apparatus state is different, in order to identify the cause, the above Patent Documents 1 and 2 are used. The same problem as in the case of.

  In addition, when using an LCR meter, it is only possible to measure the impedance at a single frequency, and the frequency measured by the LCR meter is deviated from the frequency band in which the impedance changes greatly with respect to the state of the component. In this case, accurate detection cannot be performed. In addition, the impedance value changes depending on the measurement environment and the contact state of the probe, and there is a problem that measurement value variation is large, measurement reproducibility is low, and accurate evaluation cannot be performed.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a component inspection method, a component detection apparatus, and a manufacturing apparatus that can easily detect impedance inherent to a component with high sensitivity and high accuracy.

  Another object of the present invention is to provide a component inspection method, a component inspection apparatus, and a manufacturing apparatus that can easily determine the quality of the finish at the single component level and the quality of the deterioration level and manage based on the determination.

  In the component inspection method according to the first aspect of the present invention, a pair of measuring elements in which one of the components to be measured is grounded and the other is insulated from the electronic environment in an electromagnetic shield environment grounded to ground. And a step of coupling the other measuring element to a measuring instrument including an oscillator and measuring at least one of a specific impedance and a frequency characteristic of the component to be measured.

  A component inspection apparatus according to a second aspect of the present invention forms a pair of measuring elements, one of which is grounded and sandwiching a measurement target component, and an electromagnetic shielding environment for the measurement target component and the pair of measurement components. And a shield structure that is insulated from the other of the pair of measuring elements, and a measuring instrument that supplies an electric signal to the other measuring element and measures at least one of the intrinsic impedance and the frequency characteristic of the part to be measured.

  A manufacturing apparatus according to a third aspect of the present invention includes a pair of first measuring elements that ground one surface of a measurement target component to ground and a second measuring probe that is in close contact with the measurement target component. A measuring element and a shield structure for electromagnetically shielding the pair of measuring elements from the outside are provided. In this shield structure, a film forming or etching process is performed using a measurement target component as a constituent element.

  The manufacturing apparatus according to the third aspect of the present invention further includes a movement control mechanism for moving the second probe of the pair of probe and an electric signal supplied to the second probe to be measured. A measuring instrument for measuring at least one of the intrinsic impedance and frequency characteristic of the component is provided.

  In the electromagnetic shielding environment, the contact point can be accurately realized by inserting the probe with the measurement target part, and the problem of variation in the contact state with the measurement target part that becomes a problem when using the probe is solved. Thus, a constant contact state can be realized at all times. In addition, by supplying an electrical signal using a probe isolated from the electromagnetic shield, and detecting the electrical signal returned from the component to be measured by the measuring instrument, the characteristic of the component to be measured sandwiched by the probe is detected. Impedance can be accurately detected with high sensitivity and high accuracy. Inherent impedance measurement requires frequency sweeping, so unlike the measurement at a single frequency, it is possible to accurately detect changes in the state of a component with high accuracy and accurately evaluate the performance at the component level. Can be done.

  Instead of monitoring the status of the entire device, it is possible to observe changes in the status of individual parts, and when applied to manufacturing equipment, the lower electrode, which is an important factor in process performance, should be measured. Thus, it is possible to accurately detect the apparatus state, and it becomes easy to identify the cause of failure when a failure occurs. Furthermore, the process performance can be managed based on the detection result.

[Embodiment 1]
1 schematically shows a cross-sectional structure of a component inspection apparatus according to the first embodiment of the present invention. In the following description, a case where the impedance of an electrostatic chuck that is a main component of the plasma processing apparatus is measured will be described as an example. This electrostatic chuck is a component that holds a substrate (wafer) with electrostatic force or the like during processing, and has a metal electrode sandwiched between dielectric films on its surface and insulated from the main body. The electrostatic chuck 1 corresponds to a discharge electrode in a plasma processing apparatus, a lower electrode, or a stage in an ECR type plasma processing apparatus.

  The component inspection apparatus includes a lower electrode 3 and an upper electrode 4 that sandwich the electrostatic chuck 1 that is the measurement target component. These lower electrode 3 and upper electrode 4 correspond to a pair of measuring elements.

  The electrostatic chuck 1 is fixed to the lower electrode 3 made of metal using a fixing jig 16 such as a pin on the lower electrode 3. The electrostatic chuck 1 has a laminated dielectric film 1a formed on the surface thereof. The lower electrode 3 is fixed to the lower shield 2 constituting a part of the electromagnetic shield environment using a fixing jig 9 such as a pin. By bringing the lower electrode 3 into close contact with the lower shield, unnecessary capacitance is prevented from being formed between the lower electrode 3 and the lower shield, and the electrostatic chuck 1 and the lower electrode 3 To prevent unnecessary capacitance from being formed by the gap.

  An upper shield 6 that constitutes an electromagnetic shield together with the lower shield 2 is disposed on the upper electrode 4. A through hole into which the insulator 5 is fitted is formed in the upper shield 6, and a pin 7 is slidably inserted so as to penetrate the insulator 5. The upper electrode 4 and the pin 7 are fixed, and the pin 7 and the upper electrode 4 move integrally.

  The pin 7 is slidable through the insulator 5 as described above, and the upper electrode 5 that can be moved integrally with the pin 7 is lowered by its own weight and is in close contact with the electrostatic chuck 1. That is, when there is a gap between the upper electrode 4 and the upper surface of the electrostatic chuck 1, the capacitance of the gap is interposed, and the impedance inherent to the electrostatic chuck 1 cannot be measured with high accuracy. . In order to prevent this, the upper electrode 4 can be slid up and down through the pin 7 with respect to the upper shield 6 so that the upper electrode 4 is in close contact with the upper surface of the electrostatic chuck 1. At the time of the measurement operation, after the electrostatic chuck 1 of the measurement target part is arranged on the lower electrode, the upper shield 6 is fixed to the lower shield 2, and the sliding operation via the insulator 5 is performed on the electrostatic chuck 1. The upper electrode 4 is lowered by its own weight and is in close contact with the electrostatic chuck 1. The lower electrode 3 and the upper electrode 4 are each made of, for example, a metal material having a low resistance and high conductivity. By forming each of the upper electrode 4 and the lower electrode 3 from a metal material, the upper electrode 4 can be brought into close contact with the electrostatic chuck by utilizing its own weight, and the lower electrode 3 is also loaded. The electrostatic chuck can be reliably held at the time of application.

  When the measurement target component is the electrostatic chuck 1, a thin film dielectric structure 1a is provided on the surface thereof. In contrast to such a structure, when the upper electrode 4 is made of metal, the thin film dielectric structure 1a may be damaged if the upper electrode is brought into direct contact with the laminated dielectric film 1a on the surface of the measurement target component. In this case, the surface of the upper electrode 4 may be subjected to a treatment such as coating (for example, applying a polyimide tape) in order to prevent damage to the thin film dielectric structure 11 due to such contact. As the damage-preventing coating material, a fluorine resin such as polytetrafluoroethylene may be used. Such a fluororesin has a small dielectric constant and a small coefficient of friction, and its capacitance value can be almost ignored for the measurement system, preventing damage to the laminated dielectric film etc. on the surface of the part to be measured. Measurements can be made.

  The upper electrode 4 is coupled to the electrode outlet 10 via the shield wire 13, and the electrode outlet 10 is coupled to the network analyzer 8 by the electric signal transmission line 12.

  The network analyzer 8 inputs a high frequency signal to an electric circuit or element, measures a reflected wave and a transmitted wave from the electric circuit or element, and obtains a high frequency characteristic (impedance) of the electric circuit or element to be measured. It is.

  Further, the network analyzer 8 can measure the frequency characteristics of the part to be measured in the high frequency band by sweeping the frequency of the high frequency signal. By using this network analyzer 8, it is possible to change the frequency over a wide frequency band and measure the impedance inherent to the component. Here, the impedance to be measured includes the impedance of the electrostatic chuck 1 (including the laminated dielectric film 1a) to be measured, the measurement jig, that is, the measuring element (upper electrode 4), the shield wiring 13, and the electrical signal. The total impedance is the sum of the impedances in the transmission line 12.

  The upper shield 6 is grounded (connected to ground) to the ground GND. The upper electrode 4 is insulated from the lower shield 2 and the upper shield 6 constituting the electromagnetic shield by the insulator 5. Lower electrode 3 is connected to ground by shields 2 and 6. These lower shields 2 are arranged on the table 17.

  In FIG. 1, the lower and upper shields 2 and 6 are shown to be grounded via a wire dedicated to ground. However, the upper shield 6 and the lower shield 2 may be connected to the ground (GND) via the network analyzer 8. By grounding the shields 2 and 6 to ground, an electromagnetic shield environment is formed, and the influence of electrical noise from the external environment is prevented, and the impedance inherent to the electrostatic chuck 1 is accurately and accurately reproduced. It becomes possible to measure well. Next, a component inspection method using the component inspection apparatus shown in FIG. 1 will be described.

  In the plasma etching apparatus having the electrostatic chuck 1, for example, when the film performance (finished quality; film quality, film thickness, degree of adhesion, etc.) of the laminated dielectric film structure 1 a on the surface of the electrostatic chuck 1 is different, the wafer to be processed There is a difference in the attraction force when holding the surface with electrostatic force. Usually, in the plasma etching apparatus, during etching, the wafer is held on the electrostatic chuck 1 and the etching process is controlled by cooling the wafer with helium (He) gas from the back surface. Therefore, when the wafer adsorption force is different, the degree of cooling of the wafer by helium (He) gas is different, and as a result, the etching performance varies, and when it is extremely different, the etching is abnormal. Therefore, the film performance (finished condition) of the laminated dielectric film 1a formed on the surface of the electrostatic chuck 1 is an important parameter that affects the etching performance.

  Also in the plasma film forming apparatus, the growth rate of the deposited film and the uniformity within the wafer are formed by the difference in the wafer adsorption force due to the difference in the film quality of the laminated dielectric film structure 1a on the surface of the electrostatic chuck 1. The performance will vary, and if it is extremely different, the film formation will be abnormal. Therefore, the film quality of the laminated dielectric film 11 on the surface of the electrostatic chuck 1 is an important parameter that affects the film forming performance.

  Conventionally, a technique has not been established for quantitatively comparing the film performance difference of the laminated dielectric film structure 1a on the surface of the electrostatic chuck 1 with high accuracy and high sensitivity. Therefore, even if there is an abnormality in this laminated dielectric film, if an electrostatic chuck is attached to the plasma processing apparatus, the plasma processing apparatus is started up, and the process performance is confirmed. Thus, the failure factor cannot be specified until the failure factor location is evaluated. However, by using the measurement method according to the first embodiment, the difference in the film performance of the laminated dielectric film structure 1a on the surface of the electrostatic chuck 1 is detected in advance with high sensitivity and high accuracy, and quantitatively determined. The quality can be determined by comparison or comparison with a reference electrostatic chuck.

  Here, when detecting the difference in film performance of the laminated dielectric film structure 1a on the surface of the electrostatic chuck 1, in order to prevent the information on the side surface of the electrostatic chuck 1 from being mixed, The distance between the shield 2 and the side wall surface is preferably 15 mm or more. Thereby, the influence of the parasitic capacitance formed between the side surface of the electrostatic chuck 1 and the lower shield 2 is suppressed, and the characteristic impedance of the LCR series circuit by the lower electrode 3, the electrostatic chuck 1 and the upper electrode 4 is accurately determined. Can be measured.

  FIG. 2 is a diagram showing the result of impedance measurement using the component inspection apparatus shown in FIG. In FIG. 2, the vertical axis indicates the resonance frequency Fres (unit: MHz) of the electrostatic chuck, and the horizontal axis indicates the state of each electrostatic chuck such as a defect. As an electrostatic chuck to be measured, an electrostatic chuck of a plasma oxide film etching apparatus actually used in mass production is used.

  The measured electrostatic chuck includes a genuine product and a recycled product. Samples of genuine products are genuine products of equipment manufacturers. Samples that have been used and have no problem in process performance (shown as genuine used OK in FIG. 2), samples in use (as genuine used in FIG. 2) And a new sample (shown as a genuine new product in FIG. 2). The remanufactured product is an electrostatic chuck in which the laminated dielectric film has been reclaimed by another manufacturer, and is a new sample (shown as a renewed new product in FIG. 2) and two samples in which a process abnormality occurred during use (reproduced in FIG. NG). These six electrostatic chucks are used as measurement target parts.

  As shown in FIG. 2, when the frequency of the input high frequency signal is swept, the resonance frequency Fres appears to be only a pure resistance component because the inductor component L and the capacitor component C of the impedance of the component to be measured cancel each other. It is a frequency and is a value specific to each component. Ideally, when there is no difference in component performance (film performance of the laminated dielectric film), there is no difference in the value of the resonance frequency Fres.

  In the component inspection apparatus shown in FIG. 1, an electrostatic chuck 1 (including a laminated dielectric film 1a) is sandwiched between electrodes 3 and 4 of a measuring element, and an LCR value sequence circuit is used as an electrical equivalent circuit. is there. The laminated dielectric film structure 1a on the surface of the electrostatic chuck 1 is a capacitor component. Therefore, when a difference occurs in the film performance, a difference occurs in the capacitor component, and accordingly, a difference also occurs in the resonance frequency.

  In this measurement, as a prior confirmation, it has been confirmed that the resonance frequency does not vary at all as a result of confirming the measurement reproducibility by repeated measurement on the same electrostatic chuck.

  In the genuine product, the state of the electrostatic chuck is different in the measured values of the genuine product that did not cause any problems in process performance (genuine used OK), the sample in use (genuine use in progress), and the new sample. The resonance frequency is 9.8 MHz. Therefore, in the case of a genuine product, it is considered that deterioration (cracking, tearing, peeling, floating, etc.) of the laminated dielectric film 1a does not occur either during use or after use.

  On the other hand, a difference of about 0.5 MHz is observed in the resonance frequency Fres between the genuine new product and the recycled new product. Therefore, it is considered that there is a difference in the structure of the laminated dielectric film or the film quality between these genuine new products and recycled new products. Although the materials of the dielectric thin film actually used are the same, it is known that the film thickness and the thickness of the adhesive layer are different, and this difference is considered to reflect the difference in measured values.

  In the remanufactured products, the value of the resonance frequency is about 1 MHz and the electrostatic chuck shown as the regenerated NG is larger in the renewed product and the sample in which the process abnormality occurred during use (reproduced NG). This is considered to be due to a difference in the film performance of the laminated dielectric film even in a new state, or a change over time during use. Since the resonance frequency ω is expressed by 1 / (2π√L · C), generally, when the capacitor component C is small, the resonance frequency is large (inversely proportional to √C), and the thickness d of the dielectric film is When the thickness is increased, the capacitor component is decreased (inversely proportional to d), so that it is considered that an initial failure and deterioration with time (breaking, peeling, floating, etc.) of the laminated dielectric film have occurred.

  FIG. 3 is a diagram showing an imaginary component Zi of impedance Z of an electrostatic chuck similar to the electrostatic chuck shown in FIG. The imaginary component Zi of the impedance Z is also a value determined from the inductor component L and the capacitor component C of the component-specific impedance, and this imaginary component Zi is also ideally suited to the finish (membrane performance) of the component. If there is no difference, there is no difference in the values.

  Even during this imaginary component measurement, as a prior confirmation, the same electrostatic chuck is measured several times to confirm the measurement reproducibility, and the variation is confirmed to be within 0.05Ω.

  In FIG. 3, a difference of about 0.4Ω is seen between the genuine new product and the recycled new product, similar to the resonance frequency. For genuine products, the difference in measured value between samples that were used and had no problem in process performance (genuine used OK), samples in use (genuine in use), and genuine new samples was about 0.05Ω. It is within the range of variation of measured values of the same target product, and it is considered that there is no difference in the imaginary component Zi for these genuine products as in the case of the resonance frequency.

  On the other hand, in the regenerated product, when compared with a regenerated new product, a sample in which a process abnormality occurred during use (shown as regenerated NG in FIG. 3) has an imaginary component Zi value of 0.4 or less than that of the regenerated new product. About 0.6Ω small. The imaginary component Zi of the impedance is expressed by the following equation when the frequency is ω.

Zi = j · ω · L−j / (ω · C)
Therefore, generally, when the capacitor component C is small, the value of the imaginary component Zi is small, and when the thickness d of the dielectric film is large, the capacitor component C is small (C is inversely proportional to d). Similar to the knowledge from the resonance frequency described above, it is considered that initial failure of the laminated dielectric film (film performance) and deterioration with time (breaking, cracking, peeling or floating, etc.) have occurred.

  In some plasma processing apparatuses, the lower electrode is not an electrostatic chuck, but, for example, a surface of aluminum (Al) is subjected to alumite treatment (aluminum anodic oxidation treatment). In the case of such a lower electrode structure, it is known that the process performance is affected by the quality of the alumite film (aluminum oxide film) (film performance; film quality, film thickness, etc.) (for example, coulomb as adsorption force) In the case of electrostatic chucks that use Johnson-Rahbek force instead of force, ceramic coating such as alumina is applied to the surface, and it is well known that the electrostatic chuck surface condition affects process performance. Is).

  In particular, when scratches are present on the anodized film, it is known that electric field concentration occurs due to high-frequency power in that area, plasma density (polarization) occurs within the wafer surface, and electrostatic breakdown (gate breakdown) occurs. Yes.

  This gate breakdown may be detected by visual confirmation, but depending on the level of the breakdown, the defect is not detected until the process is completed and the processed wafer is inspected in the final inspection process. Sometimes it is known that it has occurred. However, according to the component inspection method of the present invention, the alumite film on the surface of aluminum (Al) can be formed as in the case of management (quality determination) of the laminated dielectric film on the surface of the electrostatic chuck (film performance). Condition management (good / bad determination) can also be performed, and electrostatic chucks that can potentially cause gate breakdown can be detected with high accuracy.

  Similarly, in general, it is also possible to manage the finishing condition (film quality, film thickness, surface roughness, etc.) and change with time (deterioration) of a film sprayed on the surface of a component or a rubber film deposited.

  Therefore, it is possible to manage the quality (processing quality) of the dielectric film or insulating film formed on the surface of the metal member and the change with time (deterioration).

[Example of change]
FIG. 4 schematically shows a cross-sectional structure of the inspection apparatus and the measurement target component according to the first embodiment of the present invention. In FIG. 4, the upper electrode 14 as a measuring element and the measurement target component 11 are shown. The configuration of the lower electrode and the shield is the same as that shown in FIG. As shown in FIG. 4, the measurement target component 11 has an uneven portion on the surface shape. For example, when the measurement target component 11 is a lower electrode in a plasma processing apparatus, a recess for placing a wafer is provided. In such a case, the upper electrode 14 has a protrusion 14 a corresponding to the recess of the measurement target component 11. The upper electrode 14 can be brought into intimate contact with the concave portion of the measurement target component 11 by the sliding movement of the pin in the insulator 5 shown in FIG. 1 due to its own weight. It is possible to accurately measure the electrical characteristics of the measurement target component 11 without causing the measurement target component 11 and the upper electrode 14 to be in close contact with each other and generating parasitic capacitance.

  In FIG. 4, only one concave portion is formed in the measurement target component 11. However, the measurement target component 11 may be provided with a plurality of concave portions having a predetermined shape. In this case, a convex portion corresponding to the concave portion of the measurement target component 11 is formed on the upper electrode 14. Conversely, when the measurement target component 11 has a convex portion, a concave portion corresponding to the convex portion of the lower electrode 11 is formed in the upper electrode 14.

  As described above, according to the first embodiment of the present invention, the measurement target component is sandwiched between the pair of measuring elements, and the impedance or the like is measured using the measuring element insulated from the electromagnetic shield in the electromagnetic shielding environment. The characteristic is detected, the parts can be compared quantitatively, and the quality of the part to be measured can be determined with high accuracy.

[Embodiment 2]
FIG. 5 schematically shows an overall configuration of the component inspection apparatus according to the second embodiment of the present invention. The component inspection apparatus shown in FIG. 5 differs from the component inspection apparatus shown in FIG. 1 in the following points. That is, the upper electrode 24 is in pressure contact with the electrostatic chuck 1 (including the dielectric laminated film 24a) of the measurement target component via the convex portion 24a formed in a part thereof. Therefore, in the configuration of the component inspection apparatus shown in FIG. 5, the region where the convex portion 24 a contacts is the measurement region of the measurement target component (electrostatic chuck 1).

  Even in the configuration in which the convex portion 24 a is in contact with the electrostatic chuck 1, the convex portion 24 a is securely brought into close contact with the electrostatic chuck 1 of the measurement target component by the weight of the upper electrode 24 through the sliding operation of the pin 7. The The upper electrode 24 and the lower electrode 3 are made of a metal material having low resistance and high conductivity.

  The other configuration of the component inspection apparatus shown in FIG. 5 is the same as the configuration of the component inspection apparatus shown in FIG. 1, and corresponding portions are denoted by the same reference numerals, and detailed description thereof is omitted.

  When the laminated thin film dielectric structure (laminated dielectric film 24a) is formed on the surface like the electrostatic chuck 1, the component to be measured is made of metal when the convex portion 24a is made of metal. There is a risk of damaging the dielectric 1a. In order to prevent such damage to the laminated thin film dielectric, a coating film having a small dielectric constant ε is formed on the surface and side surfaces of the convex portion 24a (for example, a polyimide tape is attached). Further, a chemically stable resin film having a small dielectric constant and friction coefficient such as a fluororesin (for example, polytetrafluoroethylene (PTFE) which is a polymer of tetrafluoroethylene) may be formed.

  In the component inspection apparatus shown in FIG. 5, the upper electrode 24 is connected to the network analyzer 8 that is an impedance measuring instrument, and the lower electrode 3 and the shields 2 and 6 are also grounded via the network analyzer 8. As a result, the impedance that strongly reflects the information of the portion of the upper electrode 24 in contact with the convex portion 24a can be accurately measured with good reproducibility without being affected by electromagnetic noise from the external environment.

  In a plasma etching apparatus using an electrostatic chuck, for example, when the finish of the laminated dielectric film on the surface of the electrostatic chuck differs only partially (when scratches, peeling, or floating, etc. exist), only that part of the wafer is within the surface. A difference occurs in the adsorption force when holding the film using an electrostatic force or the like, and the etching performance partially varies, and sometimes an etching abnormality occurs. When the entire surface of the upper electrode 24 is brought into close contact with the surface of the electrostatic chuck 1 of the part to be measured, the characteristics of the entire surface of the electrostatic chuck 1 are averaged and the characteristics are observed. If the area of the part is small, there is a possibility that it cannot be detected sensitively. A projecting portion 24a is formed on the upper electrode 24, and a structure in which only the projecting portion 24a contacts the laminated dielectric film 1a on the surface of the electrostatic chuck 1 is used. The equivalent circuit of the measurement circuit is an LCR series circuit, and the capacitor component C is determined by the contact area of the convex portion 24a and can be partially measured and inspected. The film performance (finished condition) of this laminated dielectric film ) Can be detected for each part, and accurate measurement is possible. Further, by measuring the surface of the electrostatic chuck 1 partially for each contact region of the convex portion 24a, it is possible to identify a defective portion and facilitate failure analysis.

  6A and 6B are diagrams schematically showing the structure of the upper electrode 24 shown in FIG. FIG. 6A shows a plan view of the upper electrode 24, and FIG. 6B shows a cross-sectional structure of the upper electrode 24 taken along line 6B-6B.

  6A, the upper electrode 24 is illustrated in an upper electrode main body 25 in which a plurality of upper electrode convex portion mounting screw holes 27 are formed, and an upper electrode convex portion mounting screw hole 27 of the upper electrode main body 25. The upper electrode convex part 24a fixed through the screw which does not carry out is included.

  The upper electrode body 25 has upper electrode body mounting pin holes 26 formed at both ends along the diameter direction thereof. The pin 7 shown in FIG. 5 is engaged with the pin hole 26 for attaching the upper electrode main body, and the pin 7 and the upper electrode main body 25 shown in FIG.

  The upper electrode body 25 has a circular plate shape that matches the shape of the electrostatic chuck 1 of the measurement target component, and the diameter thereof is set to be equal to or slightly larger than that of the electrostatic chuck 1 of the measurement target component. The upper electrode convex portion 24a is a circular conductive plate having a diameter of several tens of millimeters, for example, and is pressure-bonded and fixed to the upper electrode concave portion mounting screw hole 27 formed in the upper electrode body 25 with a screw. A plurality of upper electrode convex portion mounting screw holes 27 are provided on the surface of the upper electrode main body 25, and the upper electrode convex portion 24a can be attached at an arbitrary position. Thereby, it is possible to perform impedance measurement at an arbitrary position by scanning the electrostatic chuck surface 1 of the measurement target component.

  6B, upper electrode body mounting pin holes 26 are formed on both sides of the upper electrode body 25, and a plurality of upper electrode protrusion mounting screw holes 27 are formed in the same shape as the screws. Formed. The upper electrode convex portion 24 a is press-fixed to the screw hole 27 by the upper electrode convex portion mounting screw 28. The upper electrode protrusion 24a is pressure-bonded to the component surface.

  In the structure of the upper electrode 24 shown in FIG. 6A, the upper electrode convex portion 24a can be positioned at the position shown by the broken line in FIG. However, the upper electrode convex portion 24a is attached only at any position in the diametrical direction, and the convex portion attaching screw hole 27 is formed in the direction along the line 6B-6B shown in FIG. The upper electrode 25 may be rotated. In order to perform this rotational scanning, for example, when the structure shown in FIG. 5 is used, the upper electrode body 25 can be equivalently rotated by rotating the upper shield 6 with respect to the lower shield. . Alternatively, instead of using the pin 7, the upper electrode may be gripped by a gripping member having a rotation mechanism, and the gripping member may be rotated during measurement. In this case, the gripping member needs to bring the upper electrode into close contact with the measurement target component with a constant load, and it is preferable that the gripping member is further provided with a load control mechanism.

  In the configuration shown in FIGS. 6A and 6B, measurement can be performed by scanning any of a plurality of positions on the surface of the electrostatic chuck 1 of the measurement target component, and an abnormal part can be easily identified. Can be done. At the time of this specification, a method is used in which the reference value of the reference electrostatic chuck and the measurement results at a plurality of locations of one electrostatic chuck are quantitatively compared to identify the presence / absence of an abnormality (a portion having a large value difference). Alternatively, the abnormal part may be identified by quantitatively comparing the measurement results of a plurality of measurement parts of one electrostatic chuck.

[Example of change]
FIGS. 7A and 7B are diagrams schematically showing another configuration of the upper electrode of the component inspection apparatus according to the second embodiment of the present invention. FIG. 7A shows a planar structure of the upper electrode 24, and FIG. 7B schematically shows a cross-sectional structure taken along line 7B-7B in FIG. 7A.

  In FIG. 7A, the upper electrode 24 is provided with an upper electrode body mounting pin hole 26 along the diameter direction of the line 7B-7B, and in the region II-IV along the diameter direction of the line 7B-7B. The upper electrode protrusion mounting screw hole 27 is formed. In each of these regions II-IV, the protrusion mounting screw holes 27 are formed in the orthogonal direction. In the region I, a plurality of protrusion mounting screw holes 27 are arranged in a region that does not overlap with the upper electrode body mounting pin hole 26. FIG. 7A shows a state in which the upper electrode protrusion 24b is fixedly attached in the region II. As shown in FIG. 7A, the upper electrode protrusion 24a has a ring shape, and the upper electrode protrusion 24b having a different size can be attached to each of the regions I, II, and IV. .

  In FIG. 7B, the upper electrode body 25 is formed with a plurality of protrusion mounting screw holes 27, and the upper electrode protrusion 24 b is closely fixed to the upper electrode body 25 with screws 28.

  In the region IV at the center of the upper electrode body 25, a circular plate-like upper electrode convex portion 24a similar to the structure shown in FIG. 6 is attached.

  In normal processes, locations where anomalies are likely to occur are often distributed along the circumferential direction of the electrostatic chuck, and plasma anomalies (differences in plasma density) may occur, especially in the central region or the peripheral region. Is expensive. Therefore, by performing measurement using the link-shaped or disk-shaped upper electrode projection 24b having a size corresponding to each region, it is possible to measure a region that is highly likely to cause an abnormality during each process. Can be detected.

  Here, the width | variety of the upper electrode convex part 24b attached in area | region I-III is several tens mm, and the upper electrode convex part attached to center part area | region IV has circular plate shape with a diameter of several tens mm. The size of the upper electrode body 25 is set to be equal to or larger than the size of the electrostatic chuck of the measurement target component.

  In the region I, the protrusion mounting screw hole 27 is formed at a position different from the position along the line 7B-7B. This is to prevent the pin hole 26 to which the upper electrode body 25 is attached from overlapping. A sliding pin (7) is fitted into the upper portion of the pin hole 26, and the upper electrode body 25 and the pin (7) are integrated. On the other hand, since the upper electrode protrusion 24b in the region I is formed on the back surface of the upper electrode body 25, the protrusion mounting screw hole 27 in the region I is formed in a region different from the upper electrode body mounting pin hole 26. By doing so, it is possible to attach the upper electrode protrusion in the outermost peripheral region I without being affected by the upper electrode body attachment pin.

  In each of the regions I-III, these ring-shaped electrodes may be further divided, and in each of the regions I-III, measurement may be performed individually in the sector-shaped divided regions.

  Even in the case of using this annular electrode, the measurement operation is the same as that in the case of using the upper electrode shown in FIG. 6, and impedance that reflects the film performance (film finish) of each region I-IV. Can be measured.

  In the case of the electrode convex structure shown in FIGS. 7A and 7B, the measurement is performed by individually scanning the portion where the process abnormality is likely to occur, and the entire surface of the electrostatic chuck of the measurement target component is small. Compared with the case of scanning and measuring in a region, it is possible to shorten the time required to identify an abnormal part.

  As described above, according to the second embodiment of the present invention, it is configured such that a plurality of locations on the surface of the measurement target component can be scanned and individually measured, and the effects of the first embodiment are achieved. In addition to this, it is possible to identify an abnormal part of the measurement target part, and it becomes easy to analyze a defect.

[Embodiment 3]
FIG. 8 schematically shows a configuration of a component inspection apparatus according to the third embodiment of the present invention. In the third embodiment of the present invention, the component inspection apparatus includes an automatic measurement system 31 that automatically measures the impedance of the measurement target component 32. The automatic measurement system 31 includes a shield 35 that realizes an electromagnetic shield environment for the measurement system, a lower electrode 34 disposed on the bottom surface of the shield 35, an upper electrode 33 disposed on the measurement target component 32, An upper electrode load control system 36 for holding the upper electrode 33 via the holding member 39 and applying a constant load is included.

  The shield 35 is configured to house the measurement target component 32 therein, and may be separable into an upper shield and a lower shield as in the first and second embodiments, and is formed on the side surface. The component to be measured may be arranged in the shield 35 by opening and closing the door. In FIG. 8, the upper electrode 33 is shown to be in contact with the measurement target component 32 by the convex portion 33a. However, the measurement electrodes 33 and 34 can be exchanged according to the shape and specific form of the measurement target component 32, and any of the electrode structures of the first and second embodiments may be used. It is not required that the convex portion 33a is provided in part.

  The holding member 39 is electrically insulated from the shield 35 and supplies a constant load to the measurement target component 32 via the upper electrode 33 under the control of the upper electrode load control system 36. Thereby, the adhesion between the upper electrode 33 and the measurement target component 32 is improved. The upper electrode load control system 36 may have an arm formed integrally with the gripping member 39 and may be configured to supply a constant load via this arm. Alternatively, the upper electrode load control system 36 holds and drives a sliding mechanism provided on the gripping member 39 that can slide up and down, and the driving pressure when the sliding mechanism is lowered is a constant value. A configuration that stops the descending sliding operation when the above is reached may be used. Therefore, various configurations can be used for supplying a constant load to the upper electrode 33.

  For example, the gripping member 39 is made of an insulating material and has a hollow structure inside. A wiring (shield wiring) for supplying an electric signal from the network analyzer 37 to the upper electrode 33 is used as an electrode extraction wiring. Be placed. The grip member 39 may be fixed to the upper electrode 33 by means such as screws or welding.

  The component inspection apparatus according to the third embodiment of the present invention further includes a computer 38 for setting the measurement conditions of the network analyzer 37, determining an error based on the measurement result, and reporting when an error occurs. The computer 38 also determines the load applied by the upper electrode load control system 36. The computer 38 includes a display device 38a, and processing such as display of measurement results, display of error determination results, and notification when an error occurs is performed using the display device 38a. The error notification may be performed using voice.

  FIG. 9 is a flowchart showing the operation of the component inspection system shown in FIG. Hereinafter, with reference to FIG. 9, the operation at the time of inspection of the component inspection system shown in FIG. 8 will be described.

  In the computer 38, information representing measurement conditions such as measurement conditions, upper electrode load amount, frequency sweep range and reference standard value is stored in advance.

  First, after placing the lower electrode 34 on the shield 36 in accordance with the measurement target component 32, the measurement target component (component) is set on the lower electrode 34 (step S1). This lower electrode 34 may always be fixed to the bottom of the shield. When the measurement target component 32 is arranged on the lower electrode 34 of the stage, the measurement target component uses a fixing jig such as a pin or a screw for the lower electrode 34 in order to prevent generation of parasitic capacitance due to the gap. And fixedly attached.

  Next, the shield 36 is sealed, and the upper electrode 33 is brought into contact with the measurement target component 32. Then, the upper electrode load control system 36 applies pressure to apply a constant load. When the shield is sealed, an electromagnetic shield forming operation is performed according to a structure in which the shield 36 can be separated into an upper shield and a lower shield or a structure in which a door that can be opened and closed is formed on the side of the shield 36. The upper electrode load control system 36 supplies a predetermined load according to the load condition data from the computer 38 (step S32). The load control system 36 may perform pressurization and pressure detection to adjust the load according to the load information from the computer 38. The load control system 36 transfers the pressure information to the computer 38, and the computer 38 transfers the pressure information. The continuation / stop of pressurization of the load control system 36 may be controlled in accordance with the pressure information.

  The electric signal propagation line from the network analyzer 37 is electrically coupled to the upper electrode 33 through the grip portion 39, and the network analyzer 37 sweeps the frequency according to the measurement condition from the computer 38, and the impedance is Measurement is performed (step S3).

  The impedance information measured by the network analyzer 37 is given to the computer 38, and is compared with the reference standard value by the computer, and a result indicating whether the measurement component is good or abnormal is displayed based on the comparison / determination result. (Step S4). In the comparison result display, when an abnormality is detected, an error is displayed, and the occurrence of an error is notified by voice or the like. At the time of automatic measurement, it is possible to easily determine the occurrence of an error, to immediately take necessary measures, and to perform component management reliably. Under the control of the computer 38, when the measurement of the necessary part of the measurement part object 32 is completed, the measurement of the measurement object part 32 is completed. By using a configuration in which the load control system 36 rotationally drives the upper electrode 33 via the grip portion 39, it is possible to perform measurement by continuously scanning a plurality of locations of the measurement target component 32.

  As described above, according to the third embodiment of the present invention, after storing the measurement target component in the electromagnetic shield using a computer, a constant load is supplied to bring the upper electrode and the measurement target component into close contact with each other. The frequency is swept under the set measurement conditions to perform impedance measurement, and parts inspection can be performed automatically and accurately in a short time. Can be done.

[Embodiment 4]
FIG. 10 schematically shows a configuration of a manufacturing apparatus according to the fourth embodiment of the present invention. This manufacturing apparatus is a parallel plate type plasma processing apparatus having a built-in impedance measuring mechanism for a single component.

  In FIG. 10, the manufacturing apparatus includes a reaction chamber 41 in which plasma is generated by exciting a reaction gas at a high frequency to perform plasma etching or film formation, a stage 44 for forming a lower electrode during discharge, a stage The reaction gas introduced into the reaction chamber 41 is exhausted by an upper electrode 45 disposed in parallel with the electrode 44, a gas introduction line 46 for introducing the reaction gas in the reaction chamber 41, and a vacuum pump (not shown). An exhaust port 47 is provided.

  The upper electrode 45 is grounded together with the reaction chamber 41 to the ground GND. The stage 44 includes an electrostatic chuck 42 which is a component to be managed and an insulator 43 on which the electrostatic chuck 42 is placed. The electrostatic chuck 42 is surrounded by an insulator 43 except for its main surface. The electrostatic chuck 42 holds a wafer disposed thereon by electrostatic force or the like, and supplies high-frequency power from the high-frequency power source 50 during processing. The insulator 43 electrically insulates the electrostatic chuck 42 functioning as the lower electrode from the reaction chamber 41 and the like.

  The manufacturing apparatus further includes a high-frequency matching unit 49 for transmitting a high frequency from the high-frequency power source 50 with high efficiency, and a relay for selectively transmitting one of the high-frequency power and the ground from the high-frequency matching unit 49 to the electrostatic chuck 42. A circuit 48, a measurement power source 51 for measuring the impedance of the electrostatic chuck 42, a measurement electrode drive system 53 for driving the measurement electrode 51, and a high frequency power to the measurement electrode 51 via the measurement electrode drive system 53 Includes a network analyzer 54 that sweeps and supplies the frequency to measure impedance, and a computer 55 that performs measurement conditions and measurement result determination in the network analyzer 54. The computer 55 is provided with a display device 55a.

  The reaction chamber 41 is provided with a measurement system storage space 52 for storing the measurement electrode 51 during normal processing. When measuring the impedance of the electrostatic chuck 42, the measurement power source 51 includes an upper electrode 51a that is in close contact with the surface of the electrostatic chuck 42 (laminated dielectric film), an arm 51b that is formed integrally with the upper electrode 51a, and a measurement. Under the control of the electrode drive system 53, an arm shaft 51c that performs vertical drive and rotational drive of the upper electrode 51a via the arm 51b is included.

  In the measurement electrode 51, a signal transmission line (shield wiring) for propagating an electric signal from the network analyzer 54 is provided along or inside the arm 51b and the arm shaft 51c.

  The high frequency power supply 50 has one end connected to the ground node (earth) GND and the other end connected to the high frequency matching unit 49. When the plasma is generated in the reaction chamber 41, the relay circuit 48 supplies high-frequency power supplied from the high-frequency power supply 50 to the electrostatic chuck 42 via the high-frequency matching unit 49. By using the high-frequency matching unit 49, high-frequency power from the high-frequency power source 50 is efficiently supplied to the electrostatic chuck 42 without generating a reflected wave, and the upper portion of the reaction chamber 41 disposed opposite to the upper portion. A high frequency electric field is formed between the electrode 45 and the electrostatic chuck 42 functioning as a lower electrode, and the reaction gas is excited to generate plasma.

  When the impedance of the electrostatic chuck 42 is measured, the relay circuit 48 grounds the electrostatic chuck 42 to the ground (connected to the ground node). The relay circuit 48 is simply. It only switches the electric signal transmission path, its size is sufficiently small, it can be installed in a small space, and it can be switched sufficiently accurately even in a high heat environment, and it can supply high frequency power during normal processing. Will not be adversely affected. Further, at the time of measurement, since the high frequency power is not supplied to the stage 44, even if the impedance of the power feeding system for the stage (electrostatic chuck) changes between the measurement time and the actual processing time, it is not affected. The impedance of the electrostatic chuck 42 can be accurately performed using the measurement electrode.

  FIG. 11 is a flowchart showing operations at the time of component inspection of the manufacturing apparatus shown in FIG. Hereinafter, with reference to FIG. 11, an operation at the time of inspection of the electrostatic chuck of the management target product in the manufacturing apparatus shown in FIG. 10 will be described.

  The measurement electrode drive system 53 performs positioning and weighting operation of the measurement electrode 51 under the control of the computer 55 (steps S10 and S11). That is, the measurement electrode 51 is accommodated in the measurement system storage space 52 as indicated by a broken line in FIG. When measuring the impedance of the electrostatic chuck 42, the measurement electrode drive system 53 performs rotation, positioning and load control of the measurement electrode 51, and causes the upper electrode 51a of the measurement electrode 51 to be in close contact with the electrostatic chuck 42 with a constant load. . As the measurement electrode drive system 53, a mechanism that performs a sliding operation and a rotation operation of the arm shaft 51c may be used, and the load of the upper electrode 51a is determined by the measurement conditions set by the computer 55. At the time of measurement, the measurement electrode 51 rotates and moves from the measurement system storage space 52 onto the electrostatic chuck 42 and further descends and contacts the electrostatic chuck 42 according to the measurement conditions set in the computer 55. The applied load is applied to the electrostatic chuck 42.

  In this state, the network analyzer 54 sweeps the frequency according to the measurement condition (sweep frequency range) set in the computer 55 and supplies high-frequency power to perform impedance measurement (step S12).

  The measurement result by the network analyzer 54 is collated with a standard value set in advance in the computer 55, and when the comparison result indicates an abnormality, an error display or voice error is issued on the display device 55a ( Step S13).

  Therefore, the electrostatic chuck impedance measurement operation in the manufacturing apparatus shown in FIG. 10 is the same as the measurement operation of the system of the component inspection apparatus shown in FIG. 8, and the processing flow shown in FIG. The measurement operation after the measurement electrode contact load is the same except that the process flow shown and the part setting and shield sealing process are not performed on the stage.

  When the manufacturing apparatus shown in FIG. 10 is used, immediately after replacement of the electrostatic chuck, it is possible to automatically determine whether the electrostatic chuck is acceptable or not under the control of the computer 55. It is possible to easily determine whether there is an abnormality. Therefore, it is not necessary to start up the manufacturing apparatus and establish a vacuum state similar to that at the time of actual processing to perform measurement, and the time required for determination can be shortened.

  Further, by setting the measurement conditions in the computer 55, the vacuum state of the manufacturing apparatus is stopped for each measurement, the electrostatic chuck is taken out, and the impedance of the electrostatic chuck is measured using a separate inspection device. After the measurement, the procedure of attaching the electrostatic chuck again to the insulator 43 of the stage 44, realizing the vacuum state with a vacuum pump and performing confirmation, and then resuming the wafer processing becomes unnecessary. Accordingly, the impedance of the electrostatic chuck 42 can be automatically and periodically observed on the spot. By accumulating the measurement data, the degree of change (deterioration) of the electrostatic chuck 42 with time can be known. Furthermore, the standard of the abnormality determination standard is set based on the accumulated data, the impedance of the electrostatic chuck 42 is automatically measured periodically under the control of the computer 55, and the measurement result is collated with the standard value. In the case where it is out of the standard, the error report is configured so that the deterioration degree of the electrostatic chuck 42 can be automatically managed.

  Further, the size of the measurement electrode 51 may be a size that can partially measure an arbitrary portion of the electrostatic chuck surface, for example, a circular plate shape having a diameter of several tens of mm, or a circular plate-like convex portion. When the measurement is performed by scanning the small electrode or the convex electrode portion over the electrostatic chuck as the electrode structure having (see Embodiment 2), the film performance of the laminated dielectric film on the surface of the electrostatic chuck (Finish) and deterioration management can be performed in units of measurement areas, and it is possible to accurately detect the presence / absence of a failure and specify a defective part.

  FIG. 12 is a diagram schematically showing the configuration of the measurement electrode driving system 53 when scanning and measuring a plurality of locations on the surface of the electrostatic chuck. In FIG. 12, the measurement electrode drive system 53 is measured by rotating the rotating mechanism 62 and moving the rotating mechanism 62 in the X and Y directions by rotating the rotating mechanism 62 and the sliding mechanism 61 and the rotating mechanism 62 coupled to the arm shaft portion 51c of the measuring electrode. An XY table 63 that moves the electrode 51 in the X and Y directions on the two-dimensional plane and positions the measurement electrode (or electrode convex portion (not shown)) at an arbitrary position of the measurement target component; The sliding control unit 64 that controls the sliding operation, the rotation control unit 65 that controls the rotating operation of the rotating mechanism 62, and the driving direction and amount of movement of the XY table 63 are controlled to place the measuring electrode 51 on the two-dimensional plane. And an X / Y drive controller 66 for moving in the Y direction.

  The sliding mechanism 61 uses the sliding control unit 64 to move the arm shaft 51c in the vertical direction and supplies a constant load during the lowering operation of the arm shaft 51c. The rotation mechanism 62 realizes the rotational movement of the measurement electrode 51 from the storage space 52 shown in FIG. 10 under the control of the rotation control unit 65. The sliding control unit 65 performs vertical movement of the measuring electrode 51 and load control. By using the XY table 63, impedance measurement can be performed using an arbitrary portion of the electrostatic chuck 42 of the measurement target part as a measurement region.

  The sliding control unit 64, the rotation control unit 65, and the X / Y drive control unit 66 are driven based on control information from the computer 55 (see FIG. 10) to measure measurement conditions (load conditions, measurement positions, etc.). The measurement electrode 51 is set in a state corresponding to the above.

  As the structure of the measurement electrode, the ring-shaped electrode structure of the modification of the second embodiment may be used, or a split ring electrode structure may be used. The electrode structure and measurement method described in the first and third embodiments can be used to realize the equipment inspection function of the manufacturing apparatus in the fourth embodiment.

  As described above, according to the fourth embodiment of the present invention, in the manufacturing apparatus, the measurement electrode is brought into close contact with the measurement target component (electrostatic chuck) by computer control, and the impedance is automatically measured. Measures process performance and equipment status automatically by removing the measurement target parts from the production equipment under the vacuum conditions of the production equipment. It can be done automatically.

  As an application part of the present invention, an electrostatic chuck, which is a component that has an important influence on process characteristics in the parallel plate type plasma processing apparatus described above, has been described as a part to be measured. However, the present invention can also be applied to the case where the lower electrode has an electrode structure different from that of the electrostatic chuck and to the case where the upper electrode is a component to be measured. Further, as a manufacturing apparatus, the present invention is also applied to components in a chamber of a manufacturing apparatus that does not involve plasma generation for performing processing according to a PVD method (physical vapor deposition method) and a thermal CVD method (chemical vapor deposition method). The invention can be applied. Further, the present invention can also be applied to a plate magnetron electrode that functions as a cathode in an ECR apparatus (an apparatus that performs film formation or etching using electron cycle ton resonance). Even when the electrode of the part to be measured is a new product and the dielectric film is not formed on the surface and the metal is exposed, the dielectric film or the conductive film is formed on the surface or etched by the process in the manufacturing process. When the surface state changes due to the impedance, the impedance changes according to the surface state, and thus the state of the component can be accurately detected. When measuring the upper electrode, the measurement is performed by raising the measurement electrode from the lower side to the lower electrode facing surface of the upper electrode.

  Further, an LCR series circuit is used as an electrical equivalent circuit of the measurement circuit, and the change in the capacitor component is observed by impedance measurement in order to detect the change in the laminated dielectric film on the surface of the electrostatic chuck. However, in general, the present invention can be applied even to a component in which a dielectric film is not formed on the surface even when the inductor component L or the resistance component R varies greatly depending on the surface state.

It is a figure which shows roughly the structure of the component inspection apparatus according to Embodiment 1 of this invention. It is a figure which shows the measurement result of the components inspection apparatus according to Embodiment 1 of this invention. It is a figure which shows the measurement result of the components inspection apparatus in Embodiment 1 of this invention. It is a figure which shows schematically the structure of the upper side electrode of the modification of Embodiment 1 of this invention. It is a figure which shows roughly the structure of the components inspection apparatus according to Embodiment 2 of this invention. (A) shows the planar structure of the upper electrode shown in FIG. 5, (B) is a figure which shows schematically the cross-sectional structure along line 6B-6B shown in FIG. 6 (A). It is a figure which shows the planar structure and sectional structure of the example of a change of the upper electrode of Embodiment 2 of this invention, respectively. It is a figure which shows schematically the structure of the components inspection system according to Embodiment 3 of this invention. It is a flowchart which shows test | inspection operation of the components test | inspection system shown in FIG. It is a figure which shows schematically the structure of the manufacturing apparatus with a built-in component inspection mechanism according to Embodiment 4 of this invention. It is a flowchart which shows the operation flow at the time of the components test | inspection of the manufacturing apparatus shown in FIG. It is a figure which shows the example of a change of the measurement electrode drive system shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Electrostatic chuck (measurement target part), 2 Lower shield, 3 Lower electrode, 4 Upper electrode, 1a Laminated dielectric film structure, 6 Upper shield, 8 Network analyzer, 14 Upper electrode, 14a Convex part, 24 Upper electrode, 24a Upper electrode convex part, 25 Upper electrode main body, 26 Upper body attaching pin hole, 27 Upper electrode convex part attaching screw hole, 28 Upper electrode convex part attaching screw, 31 Automatic measurement system, 32 Measurement object part, 33 Upper part Electrode, 34 Lower electrode, 35 Shield, 36 Upper electrode load control system, 37 Network analyzer, 38 Computer, 41 Reaction chamber, 42 Electrostatic chuck, 43 Insulator, 44 Stage, 45 Upper electrode, 46 Gas inlet, 47 Gas exhaust port, 48 relay, 49 high frequency matcher, 50 high frequency power supply, 53 measuring electrode drive system, 54 Tsu network analyzer, 55 computer, 51 measurement electrodes, 51a upper electrode, 51b, the upper electrode arm, 51c electrode arm shaft, 52 measuring electrode storage space, 61 slide mechanism, 62 rotation mechanism.

Claims (15)

Sandwiching a component to be measured with a pair of probe elements, one of which is grounded and the other of which is insulated from the electromagnetic shield environment, in an electromagnetic shield environment grounded to earth;
Coupling the other measuring element to a measuring instrument including an oscillator, and measuring at least one of a specific impedance and a frequency characteristic of the measurement target component.   The method according to claim 1, wherein at least one of one of the pair of measuring elements and the other has a shape corresponding to a surface shape of the part to be measured.   The method according to claim 1, wherein the other measuring element has a size that is equal to or smaller than the part to be measured when viewed in plan view.   The method according to claim 1, further comprising a step of measuring the other probe by scanning a plurality of locations of the measurement target component.   The method according to claim 1, further comprising determining whether there is an abnormality in the part to be measured according to the measurement result.   The method according to claim 5, further comprising a step of notifying the abnormality when an abnormality occurs according to the determination result. A pair of measuring elements, one of which is grounded and sandwiches the part to be measured,
A shield structure that forms an electromagnetic shielding environment for the part to be measured and the pair of measuring elements and is insulated from the other of the pair of measuring elements; and an electric signal is supplied to the other measuring element. A component inspection apparatus comprising a measuring instrument that measures at least one of a specific impedance and a frequency characteristic of the measurement target component. A pair of measuring elements including a first measuring element that grounds one side of the part to be measured to ground, and a second measuring element that is in close contact with at least a part of the other side of the measuring part; and A shield structure that electromagnetically shields the measurement target component from the outside, wherein the film formation or etching process is performed with the measurement target component as a component in the shield structure, and the measurement probe is rotated and the measurement is performed A manufacturing apparatus comprising: a movement control mechanism that closely contacts an object part; and a measuring device that supplies an electric signal to the second probe to measure at least one of a specific impedance and a frequency characteristic of the object part.   The apparatus according to claim 7 or 8, wherein at least one of the pair of measuring elements and / or the other has a shape corresponding to a surface shape of the part to be measured.   The apparatus according to claim 7, wherein a coating film is formed on a surface of the measurement target component.   The device according to claim 7 or 8, wherein the measuring element to which the electric signal is supplied has a size that is equal to or smaller than the part to be measured in a plan view.   The measuring element to which the electrical signal is supplied has a structure capable of changing the contact position with the measurement target component so that the measurement can be performed by scanning a plurality of locations on the surface of the measurement target. Apparatus according to claim 7 or 8.   The apparatus according to claim 7, further comprising a scanning device that causes the measuring element that receives the electric signal to scan so that a plurality of different positions on the surface of the measurement target part are measured positions.   The apparatus according to claim 7 or 8, wherein the measuring device further includes means for determining whether there is an abnormality in the part to be measured according to the measurement result.   15. The apparatus according to claim 14, wherein the measuring device further includes a reporting unit that reports the abnormality when an abnormality occurs according to the determination result.

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