JP3237743B2 - Plasma processing apparatus and plasma processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus and a plasma processing method for performing plasma processing on an object to be processed using oxygen plasma.

[0002]

2. Description of the Related Art Examples of conventional plasma processing apparatuses of this type include an etching apparatus and an ashing apparatus. The latter ashing apparatus is an apparatus for removing a mask made of an organic polymer substance used for forming an integrated circuit on a semiconductor surface by performing ashing using oxygen plasma or the like. There are various types of ashing devices. In recent years, in order to cope with large-mix low-volume production of semiconductor products and to increase the size of objects to be processed such as semiconductor wafers, the ashing apparatus has been shifting from a batch type to a single-wafer type. As an example of a single-wafer ashing apparatus, there is a down-flow type ashing apparatus using oxygen plasma, for example.

A downflow type ashing device is:
For example, oxygen plasma generated in an upper plasma generation chamber is introduced into a lower plasma processing chamber, and a mask on a surface of a semiconductor wafer on a mounting table is removed in the plasma processing chamber. The plasma generation chamber and the plasma processing chamber are defined by partitions having a large number of passage holes, which are generally called trap plates. The trap plate captures ions, and only oxygen radicals necessary for plasma processing are passed through the passage holes through the plasma. The used mask remaining in the surface of the semiconductor wafer is introduced into the processing chamber by down-flow, and the used mask is efficiently removed by ashing with oxygen radicals. Also,
When ashing is performed, unmasked portions of the semiconductor wafer surface exposed to the plasma are damaged by the plasma. Therefore, after the ashing, for example, the semiconductor wafer surface is only briefly etched with an etching gas mainly containing a fluorocarbon-based gas. Light etching (hereinafter referred to as "light etching") is performed.

Meanwhile, the trap plate is made of high-purity aluminum having excellent conductivity in order to efficiently remove ions in the plasma. The trap plate efficiently captures ions generated in the plasma generation chamber, prevents intrusion of ions into the plasma processing chamber, and prevents damage due to ion bombardment of the semiconductor wafer and charging of the semiconductor wafer. It is.

On the other hand, recently, various electric products such as a personal computer and a mobile phone have been developed, and the application fields of the semiconductor products have been diversified, and the demand for the semiconductor products has been tight. In order to meet the demand, it is necessary to produce semiconductor products with higher quality and more efficiently. From such a point, it is extremely important to improve the throughput in each processing step of semiconductor manufacturing.

[0006]

However, in the case of the conventional ashing apparatus, the ashing speed is faster than immediately after the ashing starts and a stable processing can be performed a short time after the ashing starts. Until the process (the initial period of the ashing), the ashing speed corresponding to the oxygen supply amount cannot be obtained, and there is a problem that the throughput is reduced accordingly. Although the ashing period is an initial period, the influence becomes larger as the diameter of the semiconductor wafer becomes larger and the degree of integration of the integrated circuit increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a plasma processing apparatus capable of securing a plasma processing speed commensurate with an oxygen supply amount immediately after the start of plasma processing and improving throughput. It is an object of the present invention to provide a plasma processing method.

[0008]

The present inventors have conducted various studies on the cause of the low ashing speed immediately after the start of the ashing process, and found that oxygen in the plasma generation chamber was converted from high-purity aluminum for a while immediately after the start of the ashing process. It has been found that the trapping plate is consumed to oxidize the trapping plate, the amount of plasma generated is suppressed by the consumed amount, the amount of oxygen radicals introduced into the plasma processing chamber is reduced, and the ashing speed is reduced.

The present invention has been made based on the above findings, and the plasma processing apparatus according to the first aspect of the present invention has the following features.
A plasma generation chamber that receives oxygen gas to generate oxygen plasma, a partition wall made of a conductive material that captures ion components in the oxygen plasma generated in the plasma generation chamber and passes oxygen radicals, A plasma processing chamber connected to the plasma generation chamber, and a mounting table that is provided in the plasma processing chamber and mounts an object to be processed by the oxygen radicals. The surface of the partition has a film thickness of 300 to 10000 angstroms having a dense crystal structure for preventing diffusion of oxygen atoms into the inside thereof.
That the oxide film of the conductive material is provided, it is characterized in that to prevent oxidation of the inside of the conductive material by the oxide film.

A second aspect of the present invention is directed to a plasma processing apparatus according to the first aspect, wherein the conductive material is aluminum.

A third aspect of the present invention is directed to a plasma processing apparatus according to the first or second aspect , wherein the oxide film contains fluorine.

According to a fourth aspect of the present invention, there is provided a plasma processing method comprising the steps of: receiving oxygen gas in a plasma generation chamber to generate oxygen plasma; and generating oxygen plasma in a plasma generation chamber by a partition made of a conductive material. A step of capturing an ion component in the oxygen plasma and passing oxygen radicals through a plasma processing chamber connected to the plasma generation chamber; and a step in which the workpiece is placed on a mounting table in the plasma processing chamber. A plasma treatment method comprising the step of performing a plasma treatment, wherein the oxygen radicals pass through the partition, when the surface of the partition has a dense crystal structure formed to prevent diffusion of oxygen atoms , the film thickness of 300 to 10,000 angstroms over-time
A step of preventing oxidation of the conductive material by preventing diffusion of the oxygen atoms into the partition via an oxide film of the conductive material.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in FIGS. FIG. 1 is a diagram showing a cross section of an ashing apparatus which is an embodiment of the plasma processing apparatus of the present invention. The ashing device 10 according to the present embodiment is configured as shown in FIG.
As shown in FIG. 2, a plasma generation chamber 11 that generates oxygen plasma P, and a conductive material (for example, aluminum) that captures ion components in the oxygen plasma P generated in the plasma generation chamber 11 and allows oxygen radicals to pass therethrough. A partition, ie, a trap plate 12, and a plasma processing chamber 13 connected to the plasma generation chamber 11 via the trap plate 12
It is comprised including. In addition, the plasma processing chamber 13
Is provided with a mounting table 14 on which the semiconductor wafer W is mounted.
A photoresist film (not shown) made of an organic polymer substance on the surface of the semiconductor wafer W on the mounting table 14 is removed by ashing by oxygen radicals introduced from the plasma generation chamber 11 into the plasma processing chamber 13 by downflow. It is.

The plasma generation chamber 11 has a bowl-shaped portion 11A.
And a cylindrical portion 11B extending upward from the upper end of the spherical portion of the bowl-shaped portion 12A, and is formed of, for example, quartz. A pair of upper and lower electrodes 16A and 16B is attached to the cylindrical portion 12B via a spacer 15 made of an insulating member. The upper electrode 16A is connected to a high frequency power supply 18 via a matching circuit 17, and the lower electrode 16B is grounded. Further, the gas supply pipe 19 is provided in the cylindrical portion 11B.
The gas supply source 20 is connected via the
From 0, an etching gas mainly containing an oxygen gas or a fluorocarbon-based gas such as carbon tetrafluoride is appropriately supplied. A flow regulator 21 is provided in the gas supply pipe 19, and the flow regulator 21 adjusts the flow rate of the oxygen gas or the etching gas.

The plasma processing chamber 13 connected to the plasma generation chamber 11 is formed in a flat cylindrical shape by, for example, aluminum whose surface is subjected to anodizing. A transfer path 22 for loading and unloading the semiconductor wafer W is connected to a side surface of the plasma processing chamber 13, and a gate valve 23 is attached to a loading and unloading port. Accordingly, by opening the gate valve 23, the semiconductor wafer W is transferred from the transfer path 22 into the plasma processing chamber 13 under a high vacuum.
And after the ashing, the semiconductor wafer W is placed under a high vacuum.
Can be carried out. In addition, the plasma processing chamber 1
3 is evacuated to a vacuum exhaust device 25 via a vacuum exhaust pipe 24.
Are connected, and the plasma generation chamber 11 and the plasma processing chamber 1
The inside of the chamber 3 is evacuated to a predetermined degree of vacuum, and the processed gas is discharged. In addition, the plasma processing chamber 1
A mounting table 14 is provided at the center of the bottom surface of the base 3. At the center of the mounting table 14, for example, three elevating pins 14A are provided so as to be able to move up and down, and the semiconductor wafer W is transferred in a state where the three elevating pins 14A are raised. The pins 14A are lowered, and the semiconductor wafer W is moved via an electrostatic chuck (not shown) provided on the surface of the mounting table 14.
Is electrostatically attracted to the mounting table 14.

Incidentally, the trap plate 12, which constitutes a main part of the present invention, is disposed between the plasma generation chamber 11 and the plasma processing chamber 12. This trap plate 12
As shown in FIGS. 1 and 2, a large number of passage holes 12 </ b> A are formed so as to be evenly dispersed, and oxygen radicals generated in the plasma generation chamber 11 are reduced into the plasma processing chamber 13 through the large number of passage holes 12 </ b> A. It is introduced by flow. The trap plate 12 is grounded.

On the surface of the trap plate 12, as shown in an exaggerated manner in FIG. 2, an aluminum oxide film layer 12B obtained by oxidizing aluminum is formed, and the aluminum oxide film layer 12B is formed by the aluminum oxide film layer 12B.
C is prevented from being oxidized. In other words, when active oxygen in the oxygen plasma P is adsorbed on the trap plate 12 during ashing, oxygen atoms are transferred to the aluminum oxide film layer 12B.
Therefore, diffusion into the inside is prevented, and oxygen adsorption on the surface of the trap plate 12 reaches a saturated state and is not further absorbed, thereby preventing consumption of oxygen in the plasma generation chamber 11 and stabilizing generation of oxygen radicals. In addition, oxygen radicals can be supplied in a stable state without reducing the amount of oxygen radicals supplied into the plasma processing chamber 13. As a result of the oxygen atoms not diffusing into the interior, aluminum metal 12C underlying aluminum oxide film layer 12B
Can be prevented from being oxidized. The diffusion of oxygen atoms into the inside can be prevented as described above because the crystal structure of the aluminum oxide film layer 12B formed by the oxidation treatment is much denser than the natural oxide film. Seems to be doing.

However, it is inevitable that active oxygen is adsorbed on the trap plate 12, and a small amount of active oxygen is adsorbed on the trap plate 12 immediately after the start of the treatment. Is recognized,
The amount of adsorption is negligible. The thickness of the aluminum oxide film layer 12B may be such that oxygen atoms do not diffuse into the inside, and the film thickness is preferably, for example, 300 to 10000 angstroms. If the film thickness is less than 300 angstroms, diffusion of oxygen atoms may occur, and if the film thickness exceeds 10,000 angstroms, charges due to ions and electric charges occur, which is not preferable. In addition, it was found that when the aluminum oxide film layer 12B contains fluorine, the growth of the oxide film can be suppressed, which is more effective.

In examining the variation of the thickness of the aluminum oxide film layer and the adsorption behavior of oxygen, the thickness of the aluminum oxide film layer of the trap plate was measured using an XMA analysis method utilizing X-ray diffraction. Using TDS (thermal desorption mass) analysis, the number of molecules of gas such as oxygen gas adsorbed and desorbed in the aluminum oxide film layer was measured. As a result, during light etching, the adsorbed oxygen during ashing is combined with the carbon in the etching gas by plasma of an etching gas, for example, a fluorocarbon-based gas such as carbon tetrafluoride, as schematically shown in FIG. However, the surface of the aluminum oxide film layer 12B is already in an oxygen-saturated state, and oxygen is not deprived.
B hardly changes.

On the other hand, in the case of the conventional trap plate 12 'made of pure aluminum, a natural oxide film 12'B of aluminum is formed on the surface as schematically shown in FIG. However, the natural oxide film layer is extremely thin, and adsorbed oxygen atoms easily diffuse into the interior during ashing, and the oxygen atoms diffuse to the interface with the aluminum metal 12′C as shown by the dashed arrow in FIG. Aluminum oxide film layer 1 by oxidizing aluminum metal 12'C at the interface
2′B grows gradually and the film thickness increases. Therefore, until the oxidation of the aluminum metal 12′C by the adsorbed oxygen stops, the oxygen atoms adsorbed on the surface of the trap plate 12 ′ are sequentially diffused into the inside of the trap plate 12 ′, and the oxygen on the surface is in an unsaturated state. Oxygen in the generation chamber 11 is gradually consumed, and the amount of generated oxygen radicals is reduced by the consumed amount, so that an expected ashing speed corresponding to the supply amount of oxygen cannot be obtained. However, if no further oxidation occurs, a stable ashing rate can be obtained. Therefore, a stable ashing speed can be obtained if a certain period of time elapses immediately after the start of the ashing. Further, as schematically shown in FIG. 3C, during light etching, oxygen atoms in the process of diffusion in the trap plate 12 'are consumed by carbon or the like, which is a decomposition product in the plasma of the etching gas, and the light etching speed is increased. And the oxidation of the aluminum metal 12C is suppressed.

Next, the operation will be described. First, the inside of the plasma generation chamber 11 and the plasma processing chamber 13 is evacuated to a predetermined degree of vacuum using the vacuum exhaust device 25. Thereafter, the gate valve 23 is opened, the semiconductor wafer W is loaded into the plasma processing chamber 13 from the transfer path 22 using a transfer mechanism (not shown), and the semiconductor wafer W is mounted on the mounting table 14. Close. Next, high frequency power is applied to the electrode 16A by the high frequency power supply 18 via the matching circuit 17, and oxygen gas is supplied from the gas supply source 20. At this time, the gas supply amount is controlled by the flow controller 21.
Maintains a predetermined gas flow rate.

When oxygen gas is supplied from the gas supply pipe 19 into the plasma generation chamber 11, the electrode 16A,
An oxygen plasma P is generated between 16B. At this time, since the evacuation device 25 is driven, the oxygen plasma P generated in the plasma generation chamber 11 flows downward as indicated by the arrow in FIG. At this time, the trap plate 12 is
Trap plate 1 that traps ions inside and traps only oxygen radicals
2 through a large number of passage holes 12A to the plasma processing chamber 13. In the plasma processing chamber 13, oxygen radicals react with the organic polymer compound of the photoresist film of the semiconductor wafer W, and the photoresist film is removed by ashing. Gases such as carbon dioxide and water generated by the ashing flow out of the vacuum exhaust pipe 24. After the ashing, the gas is switched from the oxygen gas to the etching gas, and the semiconductor wafer W is lightly etched to remove partial damage due to the ashing. After these series of processes are completed, the gate valve 23 is opened, the next semiconductor wafer W is replaced, and a new semiconductor wafer W is ashed.

During the ashing, oxygen in the oxygen plasma P is adsorbed on the surface of the trap plate 12.
Since 2B is applied, the adsorbed oxygen atoms are prevented from diffusing into the interior by the aluminum oxide film layer 12B, and the amount of adsorbed oxygen on the surface immediately reaches a saturated state, and there is no further adsorption. The amount of oxygen consumed in the oxygen plasma P besides ashing can be ignored, and an ashing speed commensurate with the supply amount of oxygen gas can be secured immediately after the ashing starts, and ashing can be performed at a high throughput immediately after the ashing starts. Can be. Further, at the time of light etching, a slight amount of adsorbed oxygen adsorbed on the surface of the trap plate 12 is consumed by the etching gas, but does not deprive the aluminum oxide film layer 12B.

[0024]

Next, a specific embodiment will be described with reference to FIGS. FIG. 4 is a table showing a comparison of changes in the thickness of the aluminum oxide film of the trap plate when ashing and light etching are performed using the trap plate shown in FIG. 2 and a conventional trap plate. FIG. 6 is a table showing a comparison of changes in ashing speed when ashing and light etching are repeated three times using the trap plate shown in FIG. 2 in Example 1. FIG. 6 shows a case where a new trap plate is aged. 9 is a table showing the results of analyzing adsorbed molecules adsorbed on a trap plate in order to investigate the cause of a lower ashing speed.

Example 1 In this example, a photoresist film was formed on a silicon wafer and a silicon wafer under the following conditions 1 to 3 using an ashing apparatus equipped with a trap plate provided with a 500 angstrom aluminum oxide film on the surface. Ashing was performed on the formed photoresist wafer, and the results are shown in FIG. In the present embodiment, ashing was performed three times under the condition 1 when aging was performed for 1 hour and when aging was not performed, and a change in ashing speed between the two was observed. Under conditions 2 and 3, ashing or integrated processing was performed on wafers of 1 lot (L) to 3 L (75 sheets), and the processing was repeated three times, and variations in the ashing speed between lots and the number of processings were observed. FIG. 5 shows the results of these ashing speed fluctuations. The ashing speed in FIG. 5 is an average value for each lot.

From the results of the change in the aluminum oxide film shown in FIG. 4, the following was found. That is, in the case of condition 1,
Although the thickness of the aluminum oxide film is slightly thicker than when the plasma is not irradiated, the plasma thickness of the aluminum oxide film layer is increased when the light etching under the conditions 2 and 3 is performed and the integrated processing is performed. The aluminum oxide film layer is stable with little change compared to the case where no heat treatment is performed.

Further, from the results showing the change in the ashing speed shown in FIG. 5, the following was found. That is, in the case of the condition 1, a higher ashing speed was obtained when aging was performed than when no aging was performed. In order to investigate the cause, a trap plate without plasma irradiation and a trap plate under conditions 1 and 2 irradiated with plasma were sampled, and the adsorbed gas on the surface was analyzed by TDS, and the results are shown in FIG. . According to the analysis results shown in FIG. 6, it was found that a large amount of water molecules were adsorbed in addition to oxygen molecules when the plasma was not irradiated, and that the number of adsorbed water molecules was reduced by almost half when the plasma was irradiated. . From these results, it is estimated that the absorbed water molecules were detached from the trap plate by the plasma irradiation, and the ashing speed was increased. According to the results shown in FIG. 5, there was almost no change in the ashing speed even when the ashing process was repeated. When the consistent processing was performed by adding the light etching under the conditions 2 and 3, the ashing speed was substantially constant irrespective of the number of wafer lots, and a consistently high ashing speed was obtained immediately after the start of the ashing. Also, it was found that there was no difference in the ashing speed each time even if the processing was repeated.

[Condition 1]: Only ashing with oxygen was performed under the following conditions. FIG. 3 shows changes in the ashing speed when ashing was performed without aging and when ashing was performed after aging for one hour. Object to be processed: Silicon wafer High frequency power: 700 W Vacuum: 2 Torr Gas flow rate: 1500 sccm Processing time: 5 hours [Condition 2]: Ashing with oxygen and light etching were performed under the following conditions. Object to be processed: Silicon wafer Ashing High frequency power: 700 W Vacuum degree: 2 Torr Gas flow rate: 1500 sccm Processing time: 3 minutes Light etching High frequency power: 800 W Vacuum degree: 1 Torr Gas flow rate: CF4 / O2 = 900 sccm / 100 s
ccm Processing time: 10 seconds Total processing time: 5 hours [Condition 3]: Processing was performed under the same conditions as in Condition 2 except that a photoresist wafer was used instead of a silicon wafer.

Example 2 In this example, the same processing as in Example 1 was performed using an ashing apparatus equipped with a trap plate having a surface coated with an aluminum oxide film of 2030 angstroms, and the results are shown in FIG. . According to the results shown in FIG. 4, it was found that substantially the same results as in Example 1 were obtained in this example.

Example 3 In this example, a treatment was performed in the same manner as in Example 1 using an ashing apparatus equipped with a trap plate provided with a 7050 Å aluminum oxide film on the surface, and the results are shown in FIG. . According to the results shown in FIG. 4, it was found that substantially the same results as in Example 1 were obtained in this example.

From the results of Examples 1 to 3, if the aluminum oxide film of the trap plate has a certain thickness (500 Å), a high ashing speed can be obtained immediately after the start of ashing, regardless of the film thickness. It was found that stable ashing could be continued.

Comparative Example 1 In this comparative example, ashing was performed under conditions 1 to 3 using a trap plate made of pure aluminum, and the results are shown in FIGS. 4 and 5. From the results showing the change of the aluminum oxide film in FIG. 4, the following was found. That is, in the case of the condition 1, the oxygen in the oxygen plasma is adsorbed on the surface of the trap plate and oxidation proceeds, and the aluminum oxide film grows largely. In other words, the oxygen in the oxygen plasma is consumed for oxidizing the trap plate. In addition, when the integrated processing was performed by adding the light etching of the conditions 2 and 3, the aluminum oxide film grew less than in the case of the condition 1, but the film thickness was remarkably larger as compared with the examples 1 to 3. It is growing and consumes a lot of oxygen.

Further, from the results showing the change in the ashing speed shown in FIG. 5, the following was found. That is, in the case of Condition 1, if ashing is performed without performing aging, oxygen is consumed for oxidizing the trap plate as described above, and the ashing speed is much lower than those in Examples 1 to 3. Also,
In order to obtain the ashing speed at the time of aging for 1 hour in Examples 1 to 3 in this comparative example, it is necessary to age for as long as 30 hours. In other words, it is not possible to obtain an ashing speed commensurate with the supply amount of oxygen gas for 30 hours immediately after ashing.

It should be noted that the present invention is not limited to the above-described embodiment, but can be widely applied to an etching apparatus and the like as long as the apparatus uses an oxygen gas plasma. The present invention is not limited to a wafer, and can be applied to an LCD substrate or the like.

[0035]

According to the first and fourth aspects of the present invention, a plasma generation chamber for receiving oxygen gas to generate oxygen plasma, and a plasma generation chamber for generating oxygen plasma in the plasma generation chamber. A partition wall made of a conductive material that captures ion components and allows oxygen radicals to pass therethrough; a plasma processing chamber connected to the plasma generation chamber via the partition wall; A plasma processing apparatus comprising: a mounting table for mounting an object to be processed by plasma ; and 300 to 10000 angstroms having a dense crystal structure on the surface of the partition wall to prevent diffusion of oxygen atoms into the partition wall surface.
Io thickness of the oxide film of the conductive material is provided with, for you to prevent oxidation of the inside of the conductive material by the oxide film, while maintaining the conductivity of the partition wall in the plasma
Trapping oxygen, preventing the consumption of oxygen in the plasma generation chamber, stabilizing the generation of oxygen radicals, and ensuring a plasma processing rate commensurate with the oxygen supply immediately after the start of the plasma processing. A plasma processing apparatus and a plasma processing method which can perform plasma processing on an object to be processed at a processing speed and can increase the throughput of plasma processing can be provided.

Further, according to the invention described in claim 2 and claim 3 of the present invention, in the invention described in claim 1, acid
Monolayer and inhibit the growth of, it is possible to provide a plasma processing equipment which can be more reliably stabilize the generation of oxygen radicals.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an ashing apparatus which is an embodiment of a plasma processing apparatus according to the present invention.

FIG. 2 is an explanatory diagram for explaining a cross-sectional structure of a trap plate used in the ashing device shown in FIG.

FIG. 3 is an explanatory view showing the behavior of oxygen and a fluorocarbon-based gas on the surface of a trap plate during an ashing process and light etching. FIG. FIG. 3B is a diagram showing the behavior of oxygen gas at the time of ashing on the surface of the conventional trap plate, and FIG. 3C is a diagram showing the behavior of gas at the time of light etching on the surface of the trap plate. .

FIG. 4 is a table showing a comparison of changes in the thickness of an aluminum oxide film of the trap plate when ashing and light etching are performed using the trap plate shown in FIG. 2 and a conventional trap plate.

FIG. 5 is a table showing the results of analyzing the adsorbed molecules adsorbed on the trap plate in order to find out why the ashing speed is lower than when the new trap plate is aged.

FIG. 6 is a table showing the results of analyzing adsorbed molecules adsorbed on a trap plate in order to investigate the cause of ashing speed being lower than when a new trap plate is aged.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Ashing apparatus (plasma processing apparatus) 11 Plasma generation chamber 12 Trap plate (partition wall) 12B Aluminum oxide film layer (oxide film) 12C Aluminum metal (conductive material) 13 Plasma processing chamber 14 Mounting table W Semiconductor wafer (workpiece) P oxygen plasma

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/3065 G03F 7/42

Claims (4)

(57) [Claims] 1. A plasma generation chamber for receiving oxygen gas to generate oxygen plasma, and a partition made of a conductive material that captures an ion component in the oxygen plasma generated in the plasma generation chamber and passes oxygen radicals. A plasma processing chamber connected to the plasma generation chamber via the partition wall; and a mounting table disposed on the plasma processing chamber and configured to mount an object to be processed by the oxygen radicals on the plasma processing chamber. In the processing apparatus , 300 to 10000 angstroms having a dense crystal structure for preventing oxygen atoms from diffusing into the surface of the partition wall.
A plasma processing apparatus, comprising: providing an oxide film of the conductive material having a thickness of 3 mm ; and preventing oxidation of the conductive material inside the oxide film by the oxide film. 2. The plasma processing apparatus according to claim 1, wherein said conductive material is aluminum. Wherein said oxide film, a plasma processing apparatus of claim 1 or claim 2, characterized in that it contains fluorine. Prevents diffusion of oxygen atoms 4. A process for generating oxygen plasma by receiving oxygen gas in a plasma generation chamber, capturing ion components in the oxygen plasma generated in the plasma generation chamber by a partition made of a conductive material, and generating oxygen radicals. A plasma processing method comprising the steps of: passing through a plasma processing chamber connected to a plasma generation chamber; and performing a plasma process on the target object mounted on a mounting table in the plasma processing chamber by the oxygen radical. When the oxygen radicals pass through the partition walls, the surface of the partition walls has a dense crystal structure formed to prevent diffusion of oxygen atoms, and has a thickness of 300 to 10000 angstroms.
A plasma treatment method, comprising: preventing oxygen atoms from diffusing into the inside of the partition wall through an oxide film of the conductive material having the above, thereby preventing oxidation of the conductive material.