JP2008091388A - Plasma processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide plasma processing technology capable of improving in-plane uniformity of an etching rate. <P>SOLUTION: A plasma processing apparatus includes a sample stand 6 and a plasma generating means 3 provided in a processing chamber 2 for plasma-processing a sample mounted on the sample stand by means of the generated plasma. It includes a spectrometer 14 for inducing plasma light emission around the periphery of the sample and dispersing the plasma emission light which has been induced to acquire an emission light spectrum, and a uniformity determining means 16 for analyzing the acquired emission light spectrum for determining uniformity of etching. The determining means determines that the etching rate around the periphery of the sample is higher than that in an inner peripheral part when emission light intensity of the emission light spectrum expressing a reactive product component in the acquired emission light spectrum increases and the emission light spectrum expressing a sample protective material decreases. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a plasma processing technique, and more particularly to a plasma processing technique that improves in-plane uniformity of an etching rate.

  In the semiconductor device manufacturing process, when plasma etching is performed on a wafer, one of important indexes for evaluating etching performance is the uniformity of the etching rate within the wafer surface.

  Usually, when performing the plasma etching process, a process condition that optimizes the uniformity of the etching rate within the wafer surface is obtained in advance, and the process is performed under the process condition.

  However, as the processing is repeated, the uniformity of the etching rate within the wafer surface deteriorates due to factors such as the state change in the processing chamber, and the semiconductor device acquired from the outer peripheral portion of the wafer and the semiconductor device acquired from the central portion It may make a difference in performance.

  In order to solve such problems, Patent Document 1 discloses a method for controlling the uniformity of the etching rate by adjusting the temperature of the wafer mounting table in accordance with the output signals of a plurality of endpoint detectors. ing.

Patent Document 2 discloses a method for monitoring the uniformity of an etching rate using emission spectral data when etching reaches an end point or when an inflection point is reached.
Japanese Utility Model Publication No. 63-67240 JP-A-10-74674

  In the method described in Patent Document 1, in order to detect the uniformity of the etching rate, a plurality of endpoint detectors must be installed in the upper part of the processing chamber. However, in many plasma etching apparatuses, devices such as a plasma generation apparatus, a gas introduction apparatus, and a temperature adjustment apparatus are installed in the upper part of the processing chamber, so that it is difficult to install a plurality of endpoint detectors. is there.

  Moreover, in the method of patent document 2, since a single end point detection apparatus is used, installation is easy. However, in this method, when it is determined that the uniformity of the etching rate is poor, it is unclear whether the etching rate at the outer peripheral portion of the wafer is higher or lower than that at the inner peripheral portion. For this reason, it is difficult to find a method for improving the uniformity of the etching rate with this monitoring method.

  The present invention has been made in view of these problems, and provides a plasma processing technique capable of improving the in-plane uniformity of the etching rate.

  In order to solve the above problems, the present invention employs the following means.

  In a plasma processing apparatus comprising a sample stage and plasma generating means arranged in a processing chamber, and performing plasma processing on a sample placed on the sample stage using the generated plasma, plasma in an outer peripheral portion of the sample A spectroscope for deriving emission and spectrally deriving the derived plasma emission to obtain an emission spectrum, and a uniformity determining means for analyzing the acquired emission spectrum to determine the uniformity of etching, the determination means comprising: When the emission intensity of the emission spectrum representing the reaction product component of the emission spectrum increases and the emission intensity of the emission spectrum representing the sample protective substance decreases, the etching rate at the outer periphery of the sample becomes higher than that at the inner periphery. It is determined that

  Since the present invention has the above-described configuration, it is possible to improve the in-plane uniformity of the etching rate and manufacture a semiconductor device having uniform characteristics.

  Hereinafter, the best embodiment will be described with reference to the accompanying drawings. FIG. 1 is a diagram for explaining a plasma etching apparatus according to an embodiment of the present invention. The plasma etching apparatus 1 includes a processing chamber (processing chamber) 2, a gas supply unit 8 for supplying a processing gas into the processing chamber 2, a gas exhausting unit 10 for exhausting the processing gas, and an exhaust for controlling the pressure in the processing chamber to a set value. A valve 9 is provided. Further, the processing chamber 2 includes a sample stage 6 on which a sample (wafer) 5 to be processed is placed and a plasma generation means 3 for generating plasma 4 in the processing chamber 2.

  In addition, the plasma etching apparatus 1 receives plasma light, spectroscopes 14 for generating emission spectrum data by splitting the received plasma light, emission data collection means 15 for collecting emission spectrum data, and collected emission spectrum data. An etching rate uniformity calculating unit 16 for calculating the etching rate uniformity and a sample table temperature calculating unit 18 for calculating the sample table temperature from the calculated etching rate uniformity are provided.

  In addition, an etching end point detection unit 17 that performs etching end point detection using the emission spectrum data collected by the light emission data collection unit 15 is provided. The plasma light in the processing chamber 2 is taken out through the plasma measurement window 11 and transmitted to the spectroscope 14 through the condenser lens 12 and the optical fiber 13. Further, by using the condensing lens 12, only plasma light within a specific range is extracted.

  The sample stage 6 is divided into a plurality of areas in the radial direction, and is provided with temperature control means 7a and 7b for each of the divided areas. The set temperature by the temperature control means 7a and 7b is determined by the sample stage temperature calculation means 18. .

  Thereby, the sample stage divided into a plurality in the radial direction can independently adjust the temperature of each divided area by the temperature adjusting means.

  Further, a high frequency voltage is applied to the sample stage 6 from a high frequency power source (not shown), whereby ions and the like in the plasma 4 can be attracted to the sample 5 side.

  FIG. 2 is a view of the plasma etching apparatus 1 shown in FIG. 1 as viewed from above, and is a view for explaining the mounting positions of the plasma measurement window 11, the condensing lens 12, the optical fiber 13, and the spectrometer 14.

  Normally, when measuring plasma light, as shown by a broken line in the figure, a plasma measurement window 11b, a condensing lens 12b, an optical fiber 13b, and a spectrometer 14b are installed so as to measure the central portion of the sample 5. There are many. When such an installation method is adopted, the total sum of all the plasma light from the center portion to the outer peripheral portion of the sample 5 is measured, which is suitable for measuring the entire plasma light. It is not suitable for measuring plasma light.

  In the present embodiment, as shown by the solid line in the figure, the plasma measurement window 11a, the condensing lens 12a, the optical fiber 13a, and the spectroscope 14a are installed, that is, the optical axis of the condensing lens is aligned with the outer periphery of the sample. Thus, the plasma light of only the outer peripheral portion of the sample 5 is measured.

  Incidentally, factors that cause the uniformity of the etching rate to vary with time include (1) a change in the state of the inner wall of the processing chamber 2 and (2) a change in the state of the outer periphery of the sample stage 6. In any case, these factors are based on the change over time of the parts near the outer periphery of the sample 5, so that the change in the etching rate with time varies greatly in the outer periphery of the sample 5.

  As described above, in many cases, the temporal variation of the etching rate uniformity appears as the temporal variation of the etching rate in the outer peripheral portion of the sample 5. For this reason, in measuring the etching rate uniformity, it is very important to measure the state of the outer periphery of the sample 5. For this reason, in this embodiment, it is set as the structure which measures the plasma light of the outer peripheral part of the sample 5. FIG.

  FIG. 3 is a diagram for explaining the etching rate distribution in the wafer (sample 5) plane.

  In the plasma etching apparatus, as shown in FIG. 1, the plasma distribution is improved along with the improvement such as disposing the gas exhaust means 10 directly under the sample stage 6, and the in-plane uniformity distribution of the etching rate is increased. In the case, a concentric distribution is shown. For example, the etching rate is low at the center of the wafer (sample 5), and the etching rate is high at the periphery. Therefore, in this embodiment, the uniformity of the etching rate is classified into three patterns as shown in FIG.

(1) Pattern 31 with good uniformity
(2) Pattern 32 with a high etching rate at the outer periphery of the wafer
(3) Pattern 33 having a low etching rate on the outer periphery of the wafer
FIG. 4 is a diagram for explaining the outline of the plasma etching mechanism. Substances that govern plasma etching are roughly classified into three types: reaction species 21, reaction products 22, and sample protection materials 23. The reactive species 21 present in the plasma and the sample 5 react to generate a reaction product 22 and the etching proceeds. In addition, a sample protective material 23 is used to prevent side etching or protect a portion that is not desired to be etched.

  Thus, the performance of plasma etching is largely determined by the balance of the three types of substances. In this embodiment, the uniformity of the etching rate can be measured by measuring the intensity change of the plasma light from the three types of substances.

  FIG. 5 is a diagram for explaining the plasma distribution in each of the three patterns shown in FIG. 3 (a pattern 31 with good uniformity, a pattern 32 with a high etching rate at the outer periphery of the wafer, and a pattern 33 with a low etching rate at the outer periphery of the wafer). is there.

  As substances constituting the plasma, a reactive species 21, a reaction product 22, and a sample protective substance 23 are schematically illustrated. In the figure, a indicates each emission intensity. Here, the balance of the reactive species 21, the reaction product 22, and the sample protective substance 23 in the pattern 31 with good uniformity is set to an optimum value.

  First, in the pattern 32 having a high etching rate at the outer peripheral portion of the wafer (sample 5), the sample protective material 23 is likely to adhere to the inner wall of the processing chamber 2 and the outer peripheral portion of the sample table 6. In this state, the sample protective material 23 adheres to the outer peripheral portion of the sample or the inner peripheral portion of the processing chamber, thereby reducing the absolute amount of the sample protective material 23 in the plasma on the outer peripheral portion of the wafer. For this reason, the sample protective material 23 adhering to the outer periphery of the wafer is also reduced.

  Therefore, when the reactive species 21 reacts with the wafer, it reacts more with the outer peripheral portion of the wafer where the amount of the sample protecting substance 23 is small, and the etching rate of the outer peripheral portion of the wafer increases.

  Next, in the pattern 33 having a low etching rate on the outer periphery of the wafer (sample 5), the reaction species 21 reacts with the inner wall of the process chamber 2 or the outer periphery of the sample table 6 on the inner wall of the process chamber 2 or the outer periphery of the sample table 6. Yes. In this state, the reactive species 21 are consumed on the inner wall of the processing chamber 2 or the outer periphery of the sample stage 6. For this reason, the absolute amount of the reactive species 21 in the plasma at the outer periphery of the wafer is reduced.

  Therefore, the reactive species 21 that react with the outer periphery of the wafer are reduced, and the etching rate of the outer periphery of the wafer is lowered.

  FIG. 6 is a diagram showing an emission spectrum and a radical distribution in each pattern shown in FIG. When the balance of radicals in the pattern with good uniformity is normal (reference), the emission intensity of the reaction product is monitored strongly and the emission intensity of the sample protective substance is monitored weakly in the pattern with a high etching rate on the outer periphery of the wafer. . Further, in a pattern having a low etching rate on the outer peripheral portion of the wafer, the emission intensity of the reaction product and reaction species is monitored weakly.

  That is, the uniformity of the etching rate or its variation can be estimated by monitoring the emission intensity of the reaction product, reaction species, and sample protective substance.

  If the fluctuation of the etching rate can be estimated, the etching rate is changed by changing the temperature distribution of the sample using the temperature control means 7a and 7b provided in the sample stage 6 based on the estimation result. The uniformity can be made good.

  In general, when the temperature of the sample stage is low, the sample protection substance is likely to adhere, so the etching rate is low. Conversely, when the sample stage temperature is high, the etching rate is high.

  For this reason, for example, when it is monitored that the pattern is a high etching rate on the outer peripheral portion of the wafer, the temperature of the temperature control means 7b may be set low to lower the outer peripheral temperature of the sample stage 6.

  When the etching rate changes uniformly over the entire surface of the wafer, the etching end point is detected by the etching end point detecting means 17 shown in FIG. The etching amount can be kept constant.

  FIG. 7 is a diagram for explaining the database creation process performed before the etching process. First, in step S51, a wavelength extraction database is created. FIG. 8 is a diagram showing an example of a wavelength extraction database.

FIG. 8 shows an example in which a polysilicon material on a sample is etched using a chlorine-based gas and a fluorine-based gas. In FIG. 8, the “Atom / Molecular Name” column indicates the reactive species (F, Cl), the reaction products (SiF, SiCl), and the sample protective substance (C ₂ ). These are atoms or molecules to be monitored in the plasma light. The “wavelength” column indicates the wavelength corresponding to the atom / molecule name. In the "Luminescence 1" to "Luminescence 3" columns, values from 0 to 1 are described. For example, "1" described in the "Luminescence 1 reaction product" column indicates the corresponding atom / molecule (SiF , SiCl) is a reaction product.

  That is, in the example of FIG. 8, SiF (440.1 nm) and SiCl (281.0 nm) as reaction products, F (685.6 nm) and Cl (754.7 nm) as reactive species, and C2 (512 as a sample protective substance) .9 nm) is selected. For example, the sum of the intensity of F (685.6 nm) and the intensity of Cl (754.7 nm) can be calculated as the value of the reactive species.

  The measurement of plasma light is performed in a state where the etching rate uniformity is good, the etching rate at the outer periphery of the wafer is high, and the etching rate at the outer periphery of the wafer is low. At that time, as the reaction product, the reaction species, and the sample protecting substance, it is determined which wavelength should be selected and the emission intensity should be measured, and the wavelength extraction database shown in FIG. 8 is created.

  Next, in step S52, an etching rate uniformity calculation database is created. In creating the database, first, plasma light during etching is measured, and the etching rate uniformity (uniformity distribution) at the time of measurement is measured with a film thickness measuring instrument or the like. Next, the relationship between the measured etching rate uniformity and the emission intensity of the reaction product / reaction species / sample protective substance in the plasma light is stored in the etching rate uniformity calculation database.

  FIG. 9 is a diagram illustrating an example of an etching rate uniformity calculation database. In FIG. 9, the “etching rate uniformity” column indicates that the lower the value is, the lower the etching rate at the outer peripheral portion of the wafer is. On the contrary, the higher the positive value is, the lower the etching rate is at the outer peripheral portion of the wafer. Is high.

  Further, the columns “Luminescence 1” to “Luminescence 3” indicate the relationship between the luminescence intensity of the reaction product, the reaction species, and the sample protecting material when the etching rate uniformity is shown. In this example, the emission intensity is standardized, and the etching rate uniformity is 0%, that is, the emission intensity in a good state is 100. Thus, for example, when the emission intensity of the reaction product is 60, the emission intensity of the reactive species is 50, and the emission intensity of the sample protective substance is 100, the etching rate at the outer peripheral part of the wafer is lower than that at the central part. The uniformity is calculated to be -20%.

  Next, in step S53, a sample stage temperature calculation database is created. In this step, first, in a state where the etching rate uniformity is good, the temperature of the outer periphery of the sample table is intentionally changed, for example, and the etching rate uniformity and the sample table temperature (inner periphery and The relationship of the outer peripheral temperature is recorded as a sample table temperature calculation database.

  FIG. 10 is a diagram illustrating an example of a sample stage temperature calculation database. In general, when the sample stage temperature is low, the sample protecting substance is likely to adhere, so the etching rate is low. Conversely, when the sample stage temperature is high, the etching rate is high. In the present embodiment, as described above, a concentric etching rate distribution is assumed. Therefore, as a method for changing the sample stage temperature, the sample stage temperature is changed to be concentric with respect to the sample. Is good. In this example, a database is shown when the sample stage temperature 1 (temperature of the inner peripheral part) is fixed and only the sample stage temperature 2 (outer peripheral part temperature) is changed. For example, when the sample stage temperature 2 is changed by −5 ° C. from the recipe value, the etching rate at the outer periphery of the wafer is lower than that at the inner periphery, and the uniformity of the etching rate is −10%. Has been.

  Next, in step S54, an etching process is started.

  FIG. 11 is a diagram illustrating an example of an etching process (lot process). First, an etching process is started, and plasma light data on the outer periphery of the wafer is measured by the spectroscope 14 during the etching process (steps S61 and S62). Next, the measured plasma light data is collected by the light emission data collecting means 15 (step S63), and light emission data of a necessary wavelength is extracted with reference to the wavelength extraction database shown in FIG. Subsequently, the etching rate uniformity calculation means 16 calculates the etching rate uniformity using the extracted data and the etching rate uniformity calculation database shown in FIG. 9 (step S64).

  Next, when the etching end point is detected by the etching end point detecting means 17, the etching is finished (steps S65 and S66). If all lot processing is completed, the processing is terminated (step S67).

  Next, the sample stage temperature calculation means 18 calculates the sample stage temperature using the calculated etching rate uniformity and the sample stage temperature calculation database shown in FIG. 10, and sets the temperature of the sample stage to this calculated temperature. (Step S68).

  After confirming that the temperature of the sample stage is set to a desired temperature (step S69), a wafer to be processed next is placed on the sample stage and an etching process is performed (step S70).

  In the example of FIG. 11, the sample stage temperature is set every time one sample is processed. However, it may be set every time a plurality of samples are processed, or set every lot processing. .

  FIG. 12 is a diagram showing another example of the etching process (lot process). Usually, the plasma etching process is performed in units of lots with 25 wafers as one lot. At that time, if there is time between the previous lot processing and the next lot processing, or if the products and processes in the previous lot and the next lot are different, processing using a dummy wafer called aging is performed before the lot processing. Implemented to create a processing chamber atmosphere.

  In FIG. 12, first, an etching process is started, and plasma light data on the wafer outer periphery is measured by the spectroscope 14 during the etching process (steps S81 and S82). Next, the measured plasma light data is collected by the light emission data collecting means 15 (step S83), and light emission data of a necessary wavelength is extracted with reference to the wavelength extraction database shown in FIG. Next, the aging process is terminated (step S84), and the etching rate uniformity calculation means 16 calculates the etching rate uniformity using the extracted data and the etching rate uniformity calculation database shown in FIG. (Step S85).

Next, the sample stage temperature calculation means 18 calculates the sample stage temperature using the calculated etching rate uniformity and the sample stage temperature calculation database shown in FIG. 10, and sets the temperature of the sample stage to this calculated temperature. (Step S86). After confirming that the temperature of the sample stage is set to a desired temperature, the wafer is placed on the sample stage and the etching process is performed (step S87), and then it is determined whether or not the lot process is completed ( Step S88), if not completed, the next wafer is placed on the sample stage and the etching process is performed (Step S89).
In the example of FIG. 12, the uniformity of the etching rate is calculated based on the plasma light during the aging process, and the sample stage temperature for processing the next wafer is set, but the plasma light during the aging process is set. Instead, the uniformity of the etching rate may be calculated based on the plasma light during the etching process, and the sample stage temperature when processing the next wafer may be set.

  FIG. 13 is a diagram showing details of step S65 (etching end point detection process) in FIG. Usually, the plasma etching process with end point detection includes a main etching process and an over-etching process. First, the main etching process with a high etching rate for the material to be etched is performed. After the end point is detected, the etching rate for the material to be etched is low, but the over-etching process with a high etching selectivity between the material to be etched and the underlying material is performed. By doing so, etching of the base material is prevented.

  In the present embodiment, since only the plasma light at the wafer outer peripheral portion is measured, the end point is determined based on the conditions at the wafer outer peripheral portion. That is, the state of the wafer center is not reflected as a condition for determining the end point. For this reason, as shown in FIG. 13, the over-etching time is changed according to the degree of uniformity of the etching rate (high etching rate at the wafer outer peripheral portion, good uniformity, and low etching rate at the wafer outer peripheral portion).

  In FIG. 13, first, the uniformity of the etching rate is calculated during the etching process (step S101), and then the end point is detected (step S102). When the etching rate of the wafer outer peripheral portion is high (step S103), even if the etching of the wafer outer peripheral portion is finished, it is highly likely that the etching of the wafer central portion is not finished. When the uniformity is good (steps S105 and S106), the length is set longer (step S104). Conversely, when the etching rate at the wafer outer peripheral portion is low (step S107), it is highly likely that the etching at the wafer central portion has already ended when the etching at the wafer outer peripheral portion is completed. It is shorter than when the uniformity is good (step S108). Thereby, good etching performance can be obtained on the entire wafer surface.

  So far, the example of controlling the temperature distribution of the sample stage 6 has been described as means for controlling the uniformity of the etching rate. However, the uniformity of the etching rate can be controlled by controlling the distribution of the high frequency voltage applied to the sample stage 6.

  As described above, the sample stage 6 can attract ions, radicals, and the like in the plasma 4 to the sample 5 side by applying a high-frequency voltage from a high-frequency power source. Therefore, a configuration is adopted in which a high-frequency voltage is applied to the sample stage 6 independently on the outer side and the inner side in a concentric manner. Thereby, it becomes possible to change the amount of ions and radicals attracted to the central portion and the outer peripheral portion of the sample 5, and the uniformity of the etching rate can be controlled. For example, when the etching rate of the outer periphery of the sample 5 is high, the amount of ions and radicals applied to the outer periphery of the sample 5 is reduced by lowering the high-frequency voltage outside the sample table 6, Decrease the etching rate. Thereby, the uniformity of the etching rate can be improved.

  The uniformity of the etching rate can be controlled by changing the composition of the gas supplied from each gas supply means 8 by providing the gas supply means 8 on the outside and inside of the processing chamber 2. . For example, when the etching rate of the outer periphery of the sample 5 is high, the composition of the gas supplied from the gas supply means 8 installed outside the processing chamber 2 is (1) a composition with a small amount of etchant, or (2) a large amount of sample protective substance. By using the composition, the plasma distribution in the processing chamber 2 can be changed to improve the uniformity of the etching rate.

  As described above, according to the present embodiment, the emission intensity of the emission spectrum representing the reaction product component in the emission spectrum acquired from the outer periphery of the sample increases, and the emission intensity of the emission spectrum representing the sample protective substance. When the sample rate decreases, it is determined that the etching rate of the outer periphery of the sample is higher than that of the inner periphery, and for example, the temperature of the outer peripheral side of the sample stage divided into the plurality of regions is set to be lower than the inner peripheral region. When the emission intensity of the emission spectrum representing the reaction product component and the emission spectrum representing the reactive species component in the emission spectrum acquired from the outer periphery decreases, the etching rate of the sample outer periphery is lower than that of the inner periphery. For example, the temperature of the outer peripheral side region of the sample stage divided into the plurality of regions is set to be higher than that of the inner peripheral region. It can subjected to the etching treatment at homogeneous and stable etching rate.

It is a figure explaining the plasma etching apparatus concerning the embodiment of the present invention. It is a top view of the plasma etching apparatus 1 shown in FIG. It is a figure explaining distribution of the etching rate in a wafer (sample 5) plane. It is a figure explaining the outline | summary of the mechanism of plasma etching. It is a figure explaining the plasma distribution in each of three patterns shown in FIG. It is a figure which shows the emission spectrum and radical distribution in each pattern shown in FIG. It is a figure explaining the database creation process performed before an etching process. It is a figure which shows the example of the database for wavelength extraction. It is a figure which shows the example of an etching rate uniformity calculation database. It is a figure which shows the example of a sample stand temperature calculation database. It is a figure which shows the example of an etching process (lot process). It is a figure which shows the other example of an etching process (lot process). It is a figure which shows the detail of step S65 (etching end point detection process) of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plasma etching apparatus 2 Processing chamber 3 Plasma production | generation means 4 Plasma 5 Sample 6 Sample stand 7a, 7b Temperature control means 8 Gas supply means 9 Exhaust valve 10 Gas exhaust means 11 Plasma measurement window 12 Condensing lens 13 Optical fiber 14 Spectroscope 15 Emission data collecting means 16 Etching rate uniformity calculating means 17 Etching end point detecting means 18 Sample stage temperature calculating means 21 Reactive species 22 Reaction product 23 Sample protective substance

Claims (8)

In a plasma processing apparatus comprising a sample stage and plasma generating means arranged in a processing chamber, and performing plasma processing on a sample placed on the sample stage using the generated plasma,
A spectroscope for deriving plasma emission at the outer periphery of the sample and obtaining the emission spectrum by separating the derived plasma emission;
Uniformity determining means for analyzing the acquired emission spectrum to determine the uniformity of etching,
When the emission intensity of the emission spectrum representing the reaction product component in the acquired emission spectrum is increased and the emission intensity of the emission spectrum representing the sample protective substance is reduced, the determination means determines the etching rate of the outer periphery of the sample. A plasma processing apparatus, characterized in that it is determined that the height is higher than the inner circumference. The plasma processing apparatus according to claim 1,
A plasma processing apparatus comprising: a temperature adjusting unit that divides the sample stage into a plurality of regions in a radial direction and adjusts the temperature of each of the divided regions according to a determination result of the determination unit. In a plasma processing apparatus comprising a sample stage and plasma generating means arranged in a processing chamber, and performing plasma processing on a sample placed on the sample stage using the generated plasma,
A spectroscope for deriving plasma emission at the outer periphery of the sample and obtaining the emission spectrum by separating the derived plasma emission;
Uniformity determining means for analyzing the acquired emission spectrum to determine the uniformity of etching,
The determination means is that when the emission intensity of the emission spectrum representing the reaction product component and the emission spectrum representing the reactive species component in the acquired emission spectrum is reduced, the etching rate of the outer periphery of the sample is lower than the inner periphery. The plasma processing apparatus characterized by determining. The plasma processing apparatus according to claim 3, wherein
A plasma processing apparatus comprising: a temperature adjusting unit that divides the sample stage into a plurality of regions in a radial direction and adjusts the temperature of each of the divided regions according to a determination result of the determination unit. A plasma stage that is arranged in a processing chamber and that is divided into a plurality of regions in the radial direction, and plasma generating means, and uses the generated plasma to perform plasma processing on the sample placed on the specimen stage In the method
Deriving plasma emission at the outer periphery of the sample, obtaining the emission spectrum by spectroscopically analyzing the derived plasma emission,
Among the acquired emission spectra, when the emission intensity of the emission spectrum representing the reaction product component increases and the emission intensity of the emission spectrum representing the sample protective substance decreases,
A plasma processing method, wherein a temperature of an outer peripheral region of the sample stage divided into the plurality of regions is set to be lower than an inner peripheral region. A plasma stage that is arranged in a processing chamber and that is divided into a plurality of regions in the radial direction, and plasma generating means, and uses the generated plasma to perform plasma processing on the sample placed on the specimen stage In the method
Deriving plasma emission at the outer periphery of the sample, obtaining the emission spectrum by spectroscopically analyzing the derived plasma emission,
Among the acquired emission spectra, when the emission intensity of the emission spectrum representing the reaction product component and the emission spectrum representing the reactive species component decreases,
A plasma processing method characterized in that the temperature of the outer peripheral region of the sample stage divided into the plurality of regions is set to be higher than that of the inner peripheral region. A plasma stage that is arranged in a processing chamber and that is divided into a plurality of regions in the radial direction, and plasma generating means, and uses the generated plasma to perform plasma processing on the sample placed on the specimen stage In the method
Deriving plasma emission at the outer periphery of the sample, obtaining the emission spectrum by spectroscopically analyzing the derived plasma emission,
Among the acquired emission spectra, when the emission intensity of the emission spectrum representing the reaction product component increases and the emission intensity of the emission spectrum representing the sample protective substance decreases,
A plasma processing method characterized by extending an over-etching time performed after detecting an etching end point. A plasma stage that is arranged in a processing chamber and that is divided into a plurality of regions in the radial direction, and plasma generating means, and uses the generated plasma to perform plasma processing on the sample placed on the specimen stage In the method
Deriving plasma emission at the outer periphery of the sample, obtaining the emission spectrum by spectroscopically analyzing the derived plasma emission,
Among the acquired emission spectra, when the emission intensity of the emission spectrum representing the reaction product component and the emission spectrum representing the reactive species component decreases,
A plasma processing method characterized by shortening an over-etching time performed after detection of an etching end point.

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