KR20080086063A - Combined sensor for detecting fault in a plasma process chamber incorporated with self plasma chamber - Google Patents

Abstract

A combined sensor for detecting fault in a plasma process chamber incorporated with a self plasma chamber is provided to monitor devices in a not-plasma state by separating a self plasma chamber from a process chamber. A combined sensor for detecting fault in a plasma process chamber incorporated with a self plasma chamber includes a self plasma chamber(20), a RF generator(150), a RF probe(110), a spectrometer(120), and a controller(140). The self plasma chamber is connected to an exhausted pipe to keep the process chamber in vacuum and forms a space to be in the vacuum state by injecting a gas into the process chamber. The RF generator provides a high frequency power supply which makes the gas in the self plasma chamber as a plasma state. The RF probe measures voltage and current to generate the high frequency power supply. The spectroscope measures emitting sensitivity per wave range by detecting light beam from the plasma of the self plasma chamber. The controller discriminates when the plasma process chamber has an error by analyzing the measuring result from the RF probe and the spectrometer.

Description

Combined sensor for detecting fault in a plasma process chamber incorporated with self plasma chamber

1 is a configuration diagram of a complex sensor installed in a self-plasma chamber provided separately from a plasma processing chamber according to one embodiment of the present invention;

2 is a reference diagram for explaining that a sensor for monitoring a contamination level of a self plasma chamber is installed in a self plasma chamber;

3 is a flowchart of a method of determining whether an abnormality of a process chamber is performed using a complex sensor according to a first exemplary embodiment of the present invention;

4 is a flowchart of a method of determining whether an abnormality of a process chamber is performed using a complex sensor according to a second exemplary embodiment of the present invention;

5 is a flowchart illustrating a method of determining whether an abnormality of a process chamber is performed using a complex sensor according to a third exemplary embodiment of the present invention.

6 is a flowchart illustrating a method of determining whether or not an abnormality of a process chamber is connected by connecting a high frequency probe to a high frequency generator supplying high frequency power to a self plasma chamber according to an exemplary embodiment of the present invention.

The present invention relates to plasma monitoring, and more particularly, to a composite sensor in which a self plasma chamber is provided separately from a plasma processing chamber and various sensors are coupled thereto.

Substrates of various display devices, including semiconductor wafers and liquid crystal substrates, are manufactured by repeatedly performing substrate processing steps such as forming a thin film on the substrate and partially etching the thin film. The process of forming the thin film is performed by using a chemical vapor deposition (CVD) method or a plasma-enhanced chemical vapor deposition (Plasma Enhancement CVD, PECVD) method. In addition, deposition techniques used in semiconductor processes include atomic layer deposition (ALD).

Plasma apparatuses used in such deposition processes typically include a process chamber forming a reaction space, a shower head for supplying a process gas, a lower electrode on which a substrate is seated, a power supply device for supplying power to a shower head, and a process. It includes a vacuum pump and an exhaust pipe for maintaining the chamber in a vacuum.

In order to improve the yield in such a semiconductor process, in order to prevent an accident occurring during the process and prevent a malfunction of the equipment in advance, the state of the process is monitored in real time to stop the process when an abnormal condition occurs. It is necessary to optimize the process by lowering the defective rate by taking measures of.

Conventionally, a sensor for monitoring the state of the plasma process is directly created in the monitoring window of the plasma process chamber or mounted on a window in an independent self-plasma chamber provided separately from the process chamber to monitor the state of the plasma process. In the case of using the self-plasma chamber, the material used in the process may be contaminated by the materials used in the process as in the process chamber, and the pressure change may occur as the process proceeds. May be judged. Conventionally, it was judged as it is without correcting such a contamination and pressure change.

Meanwhile, various sensors for monitoring the state of the plasma process chamber and the self-plasma chamber have existed independently. However, the high frequency power supply unit is installed in a high frequency generator that supplies high frequency energy to make gas in the plasma process chamber into a plasma state. The high frequency probe to be measured existed only in the process chamber, and the complex sensor which independently monitors the state of the self plasma chamber capable of monitoring the process without affecting the process or the process equipment by having various sensors in the self plasma chamber is Didn't exist.

Accordingly, the technical problem to be achieved by the present invention is to provide a complex sensor to monitor the state of the self-plasma chamber complex to determine the abnormality of the plasma process, and to check the malfunction of the equipment.

Another technical problem to be achieved by the present invention is to provide a method of accurately determining whether an abnormality in the plasma processing chamber using such a complex sensor than when using a single sensor independently or a plurality.

In addition, another technical problem to be achieved by the present invention is to provide a method for more accurately determining the abnormality of the plasma process chamber by detecting the pressure change of the self-plasma chamber, correcting the actual measurement value affected by the pressure change.

According to the present invention, in the composite sensor for monitoring the state in the plasma process chamber, the space connected to the exhaust pipe for maintaining the process chamber in vacuum to draw a gas in the process chamber to make a plasma state Forming a self plasma chamber; A high frequency generator for supplying a high frequency power source for making the gas in the self plasma chamber into a plasma state; A high frequency probe measuring voltage and current generating the high frequency power; A spectrometer that detects a light beam from the plasma in the self plasma chamber and measures emission sensitivity for each wavelength region; And a controller which analyzes the measurement results of the high frequency probe and the spectrometer to determine whether the plasma process chamber is abnormal.

In addition, the technical problem is a complex sensor of the plasma chamber for detecting an abnormality in the plasma process chamber, the space connected to the exhaust pipe for maintaining the process chamber in a vacuum to introduce a gas in the process chamber to make a plasma state A self plasma chamber for forming a; An optical probe for detecting a high frequency characteristic change by detecting a beam of light from a plasma in the self plasma chamber; A spectrometer that detects a light beam from the plasma in the self plasma chamber and measures emission sensitivity for each wavelength region; And it is also achieved by the composite sensor characterized in that it comprises a control unit for determining whether the abnormality of the plasma process chamber by analyzing the measurement results of the optical probe and spectroscopic analyzer.

In addition, the technical problem is a complex sensor of the plasma chamber for detecting an abnormality in the plasma process chamber, the space connected to the exhaust pipe for maintaining the process chamber in a vacuum to introduce a gas in the process chamber to make a plasma state A self plasma chamber for forming a; A high frequency generator for supplying a high frequency power source for making the gas in the self plasma chamber into a plasma state; A high frequency probe measuring voltage and current generating the high frequency power; An optical probe for detecting a high frequency characteristic change by detecting a beam of light from the plasma in the self plasma chamber; A spectrometer that detects a light beam from the plasma in the self plasma chamber and measures emission sensitivity for each wavelength region; And a control unit for analyzing the measurement results of the high frequency probe, the optical probe and the spectrometer to determine whether the plasma process chamber is abnormal.

The complex sensor may include a light source illuminating the self plasma chamber; And an optical sensor for measuring the degree of contamination of the self-plasma chamber by measuring light transmitted through the self-plasma chamber.

The complex sensor may further include a pressure sensor attached to an inlet pipe for introducing a gas in the process chamber to measure the pressure of the self plasma chamber.

On the other hand, according to another field of the present invention, the technical problem is a method for detecting the abnormality in the plasma process chamber, the gas in the process chamber through the inlet pipe connected to the exhaust pipe for maintaining the process chamber in vacuum Introducing into a separate self plasma chamber to bring it into a plasma state; Measuring a high frequency power source for bringing the gas in the self plasma chamber into a plasma state; Detecting emission beams from the plasma in the self plasma chamber and measuring emission sensitivity for each wavelength region; And analyzing the measured high frequency power supply and the emission sensitivity to determine whether the plasma process chamber is abnormal.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a complex sensor installed in a self-plasma chamber provided separately from the plasma process chamber according to an embodiment of the present invention.

The process chamber 10 forms a reaction space where substrate processing is performed, and maintains the reaction space in a vacuum and at a constant pressure and temperature. One side of the process chamber 10 further includes an exhaust pipe 40 and a vacuum pump 30 connected thereto.

The self-plasma chamber 20 is connected to one side of the exhaust pipe 40 through the inlet pipe 50, and forms a space for introducing a gas component via the exhaust pipe 40 into a plasma state. The position, length, and diameter of the inlet pipe 50 determine the optimum conditions through experiments to the extent that they do not affect the plasma process. Inlet pipes are installed according to the installation conditions of the inlet pipes thus defined such that the gas components of the exhaust pipe 40 and the gas components introduced through the inlet pipe 50 are substantially the same.

The high frequency generator 150 generates and supplies a high frequency power for making the gas in the self plasma chamber 20 into a plasma state. In order to measure the state of the supplied high frequency power source, a high frequency probe (RF probe) 110 is installed at one end of the high frequency generator 150. That is, the high frequency probe 110 monitors the state of the voltage and current of the high frequency RF supplied to the chamber 20 to monitor the state inside the chamber 20 in real time. The high frequency probe 110, also called a V-I probe, measures a root mean square (RMS) value of a voltage, an RMS value of a current, a phase relationship or a frequency of a voltage and a current, and the like.

The controller 140 may determine whether the process chamber 10 is abnormal by comparing the measured values with the values in the normal state. In other words, the measured value can be confirmed by the change of gas components or the change of temperature and pressure conditions due to equipment malfunction or process abnormality.

The spectrometer 120 receives light emitted from a gas in a plasma state from the self plasma chamber 20 through an optical fiber and measures spectral distribution according to time and wavelength. That is, the spectrometer 120 measures the spectral distribution by the plasma component, and measures the distribution according to the wavelength of light. In other words, by using the spectrometer 120 to measure the distribution value of the wavelength of light emitted from the plasma to monitor the physical and chemical state inside the chamber in real time.

The optical probe 130 checks the state of the chamber 20 by measuring a high frequency characteristic change of plasma light inside the chamber through an optical fiber fixed to a window of the chamber when a high frequency is supplied to the chamber 20. .

Data measured by the spectroscopic analyzer 120 or the optical probe 130 is transferred to the control unit 140 to calculate the state of the material used or generated in the process in real time, and determine the abnormality through the calculation result For this purpose, the state values under normal process conditions are stored and the measured values are compared. That is, it is possible to determine whether there is an abnormality according to the degree of agreement by comparing the data in the normal state with the measured data.

In this way, the control unit 140 determines the abnormality of the plasma process by combining the measurement results from the high frequency probe 110, the spectroscopic analyzer 120, and the optical probe 130, and generates an alarm or stops the process when an abnormality occurs. Lower the defective rate.

On the other hand, the pressure sensor 60 is attached to the inlet pipe 50 for introducing the gas in the process chamber 10 to measure the pressure of the self plasma chamber 20. In this case, the controller 140 corrects the measurement results from the high frequency probe 110, the spectroscopic analyzer 120, and the optical probe 130 to determine whether there is an abnormality. For example, the materials of the same component have data on how the spectrum changes with respect to the pressure change of the self plasma chamber 20, and then the actual pressure change is measured to correct the spectral measurement value. A more accurate judgment can be made by removing the spectral fluctuations and determining whether there is an abnormality using only the fluctuation ratio of the actual components.

By correcting the measurement result according to the pressure change, if it is determined that the problem is caused by a change in the plasma constituents or a problem due to a change in pressure conditions, I can identify it.

As described above, the spectrum measured by the spectroscopic analyzer 120 as well as the state of the high frequency voltage and current measured by the high frequency probe 110 and the measurement result measured by the optical probe 130 may be corrected. In other words, since the spectrometer 120, the high frequency pro 110, the optical probe 130, and the pressure sensor 60 have advantages and disadvantages, and the measurable functions are different from each other. Compensation of the results can increase the accuracy of anomalies and expand the measurable physical and chemical factors.

2 is a reference diagram for explaining that a sensor for monitoring a contamination level of a self plasma chamber is installed in the self plasma chamber.

As described above, the high frequency probe 110, the spectrometer 120, and the optical probe 130 may be provided in the self plasma chamber 20 to determine whether the process chamber 10 is abnormal. In addition, in order to monitor the contamination of the self plasma chamber 20, the light emitted from the external light source 230 passes through the diffusion plates 220a and 220b to reflect the amount of light transmitted through the self plasma chamber of the transparent material. Measure through sensor 210.

In this way, the degree of contamination of the self plasma chamber 20 itself can be measured. On the other hand, as shown in Figure 2, using a separate optical sensor 210 to measure the contamination level of the self-plasma chamber 20, using the spectroscopic analyzer 120 or the optical probe 130, the original plasma function Apart from the measurement, the change in the transmittance of the self plasma chamber 20 may be measured to measure the contamination of the self plasma chamber 20.

3 is a flowchart of a method of determining whether an abnormality of a process chamber is performed using a complex sensor according to a first exemplary embodiment of the present invention.

The gas in the process chamber is introduced into the self-plasma chamber through an inlet pipe connected to an exhaust pipe for maintaining the process chamber in vacuum (S310).

Then, the high frequency power supply for making the gas in the self plasma chamber into the plasma state is measured (S320). Next, by detecting the beam of light from the plasma in the self-plasma chamber to measure the emission sensitivity for each wavelength region (S330), by analyzing the measured high-frequency power source and the emission sensitivity to determine whether the abnormality of the plasma process chamber (S340). As described above, the determination of the abnormality may be performed according to the degree of agreement by comparing the data and the measurement data in the steady state.

On the other hand, the measurement of the high frequency power is made through a high frequency probe, the high frequency characteristics of the plasma light is measured through an optical probe. In addition, the measurement of the high frequency power supply and the measurement of the high frequency characteristic of the plasma light may be performed together.

4 is a flowchart of a method of determining whether an abnormality of a process chamber is performed using a complex sensor according to a second exemplary embodiment of the present invention.

The gas in the process chamber is introduced into a separate self plasma chamber through an inlet pipe connected to an exhaust pipe for maintaining the process chamber in a vacuum state (S410). Then, the beam of light from the plasma in the self-plasma chamber is sensed to measure the high frequency characteristic change of the plasma light (S420). In addition, by detecting the beam of light from the plasma in the self-plasma chamber to measure the emission sensitivity for each wavelength region (S430).

The abnormality of the plasma process chamber is determined by analyzing the high frequency characteristic change and the emission sensitivity of the plasma light thus measured (S440).

5 is a flowchart of a method of determining whether an abnormality of a process chamber is performed using a complex sensor according to a third exemplary embodiment of the present invention.

The gas in the process chamber is introduced into a separate self plasma chamber through an inlet pipe connected to an exhaust pipe for maintaining the process chamber in a vacuum state (S510). In operation S520, a high frequency power supply for making the gas in the self plasma chamber into a plasma state is measured. In addition, by detecting a beam of light from the plasma in the self-plasma chamber, the high frequency characteristic change of the plasma light is measured (S530). In addition, by detecting the light beam from the plasma in the self-plasma chamber, the emission sensitivity is measured for each wavelength region (S540).

The abnormality of the plasma process chamber is determined by analyzing the measured high frequency power source, the change of high frequency characteristics, and the emission sensitivity for each region (S550).

In summary, the abnormality detecting method according to FIG. 3 is a method for detecting abnormality using a complex sensor having a high frequency probe and a spectrometer, and the abnormality detecting method according to FIG. 4 includes an optical probe and a spectroscopic analyzer. The abnormality detection method using a composite sensor, and the abnormality detection method according to FIG. 5 is a method of detecting the abnormality using a composite sensor having all of a high frequency probe, a spectroscopic analyzer and an optical probe.

6 is a flowchart illustrating a method of determining whether an abnormality of a process chamber is detected by connecting a high frequency probe to a high frequency generator supplying high frequency power to a self plasma chamber according to an embodiment of the present invention.

The gas in the process chamber is introduced into a separate self-plasma chamber through an inlet pipe connected to an exhaust pipe for maintaining the process chamber in a vacuum state (S610). Then, the high frequency power supply for making the gas in the self plasma chamber into the plasma state is measured (S620).

The abnormality of the plasma process chamber is determined based on the state of the high frequency power source measured as described above (S630).

Meanwhile, in the above-described method of determining whether the plasma chamber is abnormal with reference to FIGS. 4 to 6, the pressure of the self-plasma chamber may be measured using a pressure sensor to correct the measurement result of the high frequency probe, the spectrometer, or the optical probe. .

So far I looked at the center of the preferred embodiment for the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

As described above, according to the present invention, since the self-plasma chamber separate from the process chamber is used, high frequency is not supplied to the process chamber, and thus the abnormality of the apparatus may be monitored even when the plasma is not in the plasma state. In addition, in a device using a remote plasma, such as CVD, it is impossible to optically check the plasma in the window, but even in this case, the state of the chamber may be confirmed through the optical measurement.

In addition, since the high frequency supplied to the self-plasma chamber is measured by using a high frequency probe, the high frequency supplied to the process chamber can be measured without affecting the high frequency driving of the main equipment. Furthermore, the reliability and accuracy of data can be improved by checking the status using complex measurement results such as high frequency probes, spectroscopic analyzers and optical probes.

In addition, the pressure sensor is used to calibrate the measurement results of high-frequency probes, spectrometers, and optical probes, making it possible to make more accurate judgments. By calibration, the absolute value of the process material can be measured. Therefore, the cause of process abnormality can be identified more accurately.

Claims (11)

In the complex sensor for monitoring the state in the plasma process chamber, A self-plasma chamber connected to an exhaust pipe for maintaining the process chamber in vacuum to form a space for introducing a gas in the process chamber into a plasma state; A high frequency generator for supplying a high frequency power source for making the gas in the self plasma chamber into a plasma state; A high frequency probe measuring voltage and current generating the high frequency power; A spectrometer that detects a light beam from the plasma in the self plasma chamber and measures emission sensitivity for each wavelength region; And And a controller which analyzes the measurement results of the high frequency probe and the spectrometer to determine whether the plasma process chamber is abnormal. In the composite sensor of the plasma chamber for detecting the abnormality in the plasma process chamber, A self-plasma chamber connected to an exhaust pipe for maintaining the process chamber in vacuum to form a space for introducing a gas in the process chamber into a plasma state; An optical probe for detecting a high frequency characteristic change by detecting a beam of light from the plasma in the self plasma chamber; A spectrometer that detects a light beam from the plasma in the self plasma chamber and measures emission sensitivity for each wavelength region; And And a controller which analyzes the measurement results of the optical probe and the spectrometer to determine whether the plasma process chamber is abnormal. In the composite sensor of the plasma chamber for detecting the abnormality in the plasma process chamber, A self-plasma chamber connected to an exhaust pipe for maintaining the process chamber in vacuum to form a space for introducing a gas in the process chamber into a plasma state; A high frequency generator for supplying a high frequency power source for making the gas in the self plasma chamber into a plasma state; A high frequency probe measuring voltage and current generating the high frequency power; An optical probe for detecting a high frequency characteristic change by detecting a beam of light from the plasma in the self plasma chamber; A spectrometer that detects a light beam from the plasma in the self plasma chamber and measures emission sensitivity for each wavelength region; And And a controller configured to analyze the measurement results of the high frequency probe, the optical probe, and the spectrometer to determine whether the plasma process chamber is abnormal. The method according to any one of claims 1 to 3, And a pressure sensor attached to an inlet pipe for introducing a gas in the process chamber to measure a pressure of the self plasma chamber. The method of claim 4, wherein the control unit Comprising the measurement results of the high-frequency probe, optical probe or spectroscopic analyzer with the measured value of the pressure sensor, characterized in that determining whether the abnormality of the plasma process chamber. The method according to any one of claims 1 to 3, A light source illuminating the self plasma chamber; And And a light sensor for measuring contamination of the self plasma chamber by measuring light transmitted through the self plasma chamber. The method of claim 6, And a diffuser plate positioned between the light source and the self plasma chamber to diffuse light that illuminates the self plasma chamber. In the method for detecting the abnormality in the plasma process chamber, Introducing a gas in the process chamber into a separate self-plasma chamber into a plasma state through an inlet pipe connected to an exhaust pipe for maintaining the process chamber in vacuum; Measuring a high frequency power source for bringing the gas in the self plasma chamber into a plasma state; Detecting emission beams from the plasma in the self plasma chamber and measuring emission sensitivity for each wavelength region; And And analyzing the measured high frequency power and the emission sensitivity to determine whether the plasma process chamber is abnormal. In the method for detecting the abnormality in the plasma process chamber, Introducing a gas in the process chamber into a separate self-plasma chamber into a plasma state through an inlet pipe connected to an exhaust pipe for maintaining the process chamber in vacuum; Detecting a high frequency characteristic change of the plasma light by detecting a beam of light from the plasma in the self plasma chamber; Detecting emission beams from the plasma in the self plasma chamber and measuring emission sensitivity for each wavelength region; And And analyzing the high frequency characteristic of the plasma light and the emission sensitivity to determine whether the plasma process chamber is abnormal. In the method for detecting the abnormality in the plasma process chamber, Introducing a gas in the process chamber into a separate self-plasma chamber into a plasma state through an inlet pipe connected to an exhaust pipe for maintaining the process chamber in vacuum; Measuring a high frequency power source for bringing the gas in the self plasma chamber into a plasma state; Detecting a high frequency characteristic change of the plasma light by detecting a beam of light from the plasma in the self plasma chamber; Detecting emission beams from the plasma in the self plasma chamber and measuring emission sensitivity for each wavelength region; And And analyzing the measured high frequency power source, the high frequency characteristic change, and emission sensitivity for each region to determine whether the plasma process chamber is abnormal. The method of any one of claims 8 to 10, wherein the determining whether the abnormality is Measuring the pressure of the self-plasma chamber and correcting the measurement result of the high frequency probe, the optical probe or the spectroscopic analyzer to determine whether the plasma process chamber is abnormal.

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