JPH10233389A - Semiconductor treatment apparatus and its cleaning method as well as manufacture of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to accelerate desorption of residual moisture inside a treatment container chamber uniformly and with high efficiency in an accelerated manner and to reduce downtime due to a maintenance operation by a method wherein an inner container composed of a dielectric material whose dielectric loss with reference to microwaves is larger than that of quartz is arranged and installed inside the treatment container chamber so as to cover its inner wall surface. SOLUTION: In a dry etching treatment apparatus which uses a microwave plasma, in a state that no process gas is introduced, microwaves 18 which are generated by a microwave oscillator 15 are introduced into a plasma generation chamber 4 through a microwave waveguide 16 and a microwave introduction window 17 with reference to the inside of a treatment container chamber 3 which finishes a cleaning operation and which starts a vacuum evacuation operation by a main evacuation pipe 11. The energy of the introduced microwaves 18 is absorbed by residual moisture 14 with high efficiency so as to be overheated. The remaining moisture 14 which absorbs the energy is removed easily from the inner wall surface of the treatment container chamber 3 and from the surface of an inner container 6 so as to be discharged and removed to the outside of the apparatus through the main evacuation pipe 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor processing apparatus and a method of cleaning the same in LSI manufacturing, and a method of manufacturing a semiconductor device. Is intended to be uniformly and efficiently removed.

[0002]

2. Description of the Related Art Generally, in a semiconductor processing apparatus, for example, a dry etching processing apparatus using reactive plasma,
Etching is performed by a chemical / physical reaction between the reactive particles in the reactive plasma and the film to be etched on the semiconductor substrate. At this time, a large amount of reaction products are generated as by-products. As the cumulative processing time of the semiconductor substrate increases, a large amount of the reaction product adheres and accumulates on the inner wall surface in the processing chamber or the surface of the inner container disposed in the processing chamber. As a result, the deposited and deposited reaction products re-adhere to the semiconductor substrate being processed, deteriorating the process performance,
If the physical adhesion limit is exceeded, the particles may peel off and cause particles.

Therefore, in general, in order to prevent this,
Maintenance such as so-called dry cleaning processing for cleaning the inside of the processing container chamber or removing attached reaction products by using reactive plasma is performed.

In cleaning, the apparatus is disassembled, and reaction products attached to the inner wall surface of the processing chamber and the inner container are removed using pure water or hydrofluoric acid. The inner container protects the inner wall surface of the processing container chamber from damage caused by processing and facilitates maintenance such as cleaning.However, a narrow gap is formed between the inner container and the inner wall surface of the processing container chamber, which will be described later. Such a problem arises.

[0005] After the cleaning is completed, the apparatus is assembled in the original state, and the inside of the processing chamber is evacuated again until a predetermined vacuum performance is reached. Then, when a certain vacuum performance is reached, the process is restarted. However, since water remaining on the inner wall surface of the processing container chamber and the surface of the inner container at the time of cleaning is constantly released into the processing container chamber, depending on the case, a vacuum of 24 hours or more may be required to reach a certain vacuum performance. Pulling time may be required. Therefore, as a method of shortening the evacuation time, a method of accelerating desorption of residual moisture by plasma discharge or heating by an external heater is conventionally known.

FIG. 8 shows a series of flows from processing of a semiconductor substrate to cleaning and resuming processing in a conventional method using a plasma discharge and an external heater.
The conventional method will be described below with reference to this flowchart. In the figure, reference numerals 201 to 208 correspond to the respective steps of etching, process performance check, periodic cleaning, evacuation and heater heating, vacuum degree check, plasma discharge, vacuum performance check, and process restart.

FIG. 9 is a conceptual diagram illustrating a cross section of a conventional semiconductor processing apparatus, for example, a dry etching processing apparatus using microwave plasma, and a method of heating residual moisture in a conventional method.

In FIG. 9, 1 is a semiconductor substrate, 2 is a stage on which the semiconductor substrate 1 is mounted, 3 is a processing chamber, 4 is a plasma generation chamber of the processing chamber 3, and 5 is a reaction chamber of the processing chamber 3. , 6a is an inner container arranged in the plasma generation chamber 4, 6b is an inner container arranged in the reaction vessel chamber, 7 is a connecting part between the inner containers 6a and 6b, 8a and 8b are inner wall surfaces of the plasma generation chamber 4. 8c between the inner container and the inner container 6a
Is a gap between the inner wall surface of the reaction vessel chamber 5 and the inner container 6b, 9 is a corner portion of the processing vessel chamber 3, 10 is an external heater, 11 is a main exhaust pipe, 12 is a gas inlet, and 13 is a process gas. , 14 are the moisture remaining in the processing vessel chamber 3, 15
Is a microwave oscillator, 16 is a microwave waveguide, 17 is a microwave introduction window, 18 is a microwave, 19a is a plasma discharge by an inert gas, 20 is an ion generated in the plasma discharge 19a, and 21 is a plasma discharge in the plasma discharge 19a. Radiant heat from

First, after etching a semiconductor substrate for a predetermined time (201), it is checked whether the process performance such as an etching rate is within a standard (20).
2). If it is within the standard, the process is further performed for a certain period of time, and if it is out of the standard, the above-described cleaning is performed (203).
Next, when the cleaning is completed, the apparatus is assembled in the original state, and the inside of the processing chamber 3 is evacuated again (204). At the same time, the inside of the processing chamber 3 is heated by using the external heater 10 which is one of the conventional methods, so that the residual moisture 14
Accelerates desorption. Next, after evacuation for a certain period of time, it is checked whether the pressure in the processing chamber 3 is 10 ⁻⁴ or less (205). If the pressure has not been reached, the evacuation is further continued. The heating by 19a is performed (206). Here, the reason why such a low pressure is required for performing the plasma discharge 19a is to stably generate plasma, but it takes about 10 hours for evacuation to reach the low pressure.

In the method using plasma discharge, as shown in FIG. 9, a plasma discharge 19a by an inert gas such as argon gas is generated in the processing chamber 3, and ions 20 (eg, argon) generated during the discharge are generated. Ion (A
r ⁺ )) is accelerated by the electric field in the plasma and the inner container 6
The desorption of the residual moisture 14 is accelerated by utilizing the heat generated when colliding with the surfaces of the a and 6b or the radiant heat 21 generated by the radiation generated in the plasma discharge 19a. The desorbed residual water 14 is immediately discharged to the outside of the processing chamber 3 through the main exhaust pipe 11 and removed.

Next, after performing this plasma discharge for a certain period of time, the pressure in the processing chamber 3 is checked (207).
This is repeated until the specified pressure is reached. Then, when the pressure reaches the specified pressure, the processing is restarted (208).

According to the above-described method, the time from the completion of cleaning until the processing can be resumed can be reduced from 24 hours to about 12 hours.

The method for accelerating the desorption of residual moisture after cleaning has been described above. Next, the reaction product deposited and deposited is directly used by reactive plasma without performing such cleaning. The dry cleaning process to be removed will be described. FIG. 10 is a conceptual diagram illustrating a cross section of a dry etching apparatus using the same microwave plasma as in FIG. 9 and a method for removing a reaction product by a dry cleaning process.

In FIG. 10, reference numeral 19b denotes a plasma discharge caused by a reactive gas, 22 denotes a reaction product adhered in the processing vessel chamber 3, 23 denotes a reactive ion generated in the plasma discharge 19b, and 24 denotes a plasma discharge in the plasma discharge 19. The generated reactive particles 25 are highly volatile reaction products formed by the reaction between the reaction product 22 and the reactive ions 23 or the reactive particles 24, and the other symbols are the same as those in FIG. is there.

The dry cleaning process is performed when the process performance is degraded due to the cumulative processing of the semiconductor substrate in the same manner as the above-mentioned cleaning, and the reaction products adhered and deposited in the processing chamber are subjected to a reactive gas. It is removed by plasma discharge. For example, as shown in FIG. 10, when polysilicon on a semiconductor substrate is etched using chlorine gas, a reaction product 22 such as silicon chloride (SiCl) is formed by a reaction between polysilicon and reactive particles in chlorine plasma. Is generated and adheres and accumulates in the room,
The reaction product 22 is formed of reactive particles 24 (for example, carbon tetrafluoride molecules (eg, carbon tetrafluoride (CF ₄ )) in a reactive gas plasma 19 b such as carbon tetrafluoride (CF ₄ ) newly generated in the room to remove the reaction product 22. CF ₄ )) and reactive ions 23 (for example,
By a physical and chemical reaction with carbon tetrafluoride (CF ₄ ⁺ ), a more volatile reaction product 25 (for example,
Desorption is accelerated as silicon fluoride (SiF). The desorbed reaction product 25 is immediately discharged out of the apparatus through the main exhaust pipe 11 and removed.

[0016]

In the above-described method of heating residual moisture by plasma, a sufficient heating effect of residual moisture can be obtained depending on the shape of the processing chamber 3 and the arrangement of the inner containers 6a and 6b. Some parts cannot be obtained. That is, as shown in FIG. 9, the corner portion 9 in the processing chamber is hardly exposed to the plasma due to the nature of the plasma.
Since a portion such as the narrow gap 8 sandwiched between the processing container chamber 3 and the inner container 6 is basically not exposed to the plasma, a sufficient heating effect by the plasma cannot be obtained in these portions. Also, in the method using the external heater 10,
Due to physical restrictions such as the size, shape, and location of the heater, a portion where a sufficient heating effect cannot be obtained occurs. Therefore, the evacuation time until reaching a certain evacuation performance is determined by the desorption rate in such a portion, and thus does not lead to a significant reduction in evacuation time.

In the method using plasma discharge, the pressure in the processing chamber needs to be reduced to about 10 ⁻⁴ Torr in order to discharge plasma, but it takes a considerable time to reach the low pressure. Was required.

Further, since the exhaust efficiency is generally low in a spatially narrow area such as the gap 8, the moisture desorbed in this area cannot be sufficiently discharged from the apparatus only by exhausting from the main exhaust pipe 11. There were also problems.

Further, in the conventional method of removing reaction products by dry cleaning, the effect of removing a portion which is hardly exposed to plasma or hardly exposed to plasma is the same as in the method of heating residual moisture by plasma discharge. Was not enough. Further, the present process is originally a process utilizing an etching reaction. For example, when a fluorine-based gas plasma such as carbon tetrafluoride (CF ₄ ) or nitrogen trifluoride (NF ₃ ) is used, this process is usually performed. Since the inner container 6 itself made of a dielectric material such as quartz also has a considerable etching rate, there is a problem that the parts are worn out or damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. A first object of the present invention is to uniformly and efficiently accelerate the desorption of residual moisture in the entire processing vessel chamber, and to reduce the amount of residual water by maintenance. It is an object of the present invention to obtain a semiconductor device and a cleaning method for reducing the time.

A second object of the present invention is to improve the exhaust efficiency in a narrow gap in a semiconductor processing apparatus, thereby promoting the removal of water in the area, and reducing the downtime due to maintenance, and a method of cleaning the same. Is what you get.

A third object of the present invention is to provide a cleaning method capable of uniformly and efficiently removing a reaction product in the entire processing vessel chamber without exhaustion or breakage of the inner container.

A fourth object is to provide a method for manufacturing a highly reliable semiconductor device.

[0024]

A microwave generator and a processing chamber for processing a semiconductor substrate are disposed in the processing chamber so as to cover an inner wall surface thereof, and a dielectric loss with respect to the microwave is larger than that of quartz. It has an inner container made of a body material.

Further, a dielectric material having a dielectric loss greater than that of quartz with respect to microwaves is disposed in a gap between the processing container chamber and the inner container.

Further, a step of removing reaction products generated in the step of processing the semiconductor substrate and adhering to the inside of the processing chamber by washing with a chemical containing pure water or moisture, and after the washing is completed, exhausting the inside of the processing chamber. And a step of introducing microwaves without introducing a process gas into the processing chamber.

Also, a microwave container, a plasma generating chamber, and a processing chamber for processing a semiconductor substrate are connected to a processing container chamber, an inner container disposed in the processing container chamber, and a gap between the processing container chamber and the inner container. And a bypass line communicating a gap between the vacuum evacuation line, the processing container chamber and the inner container chamber, and a desired position of the processing container chamber.

Further, a purge gas introduction line is provided which is connected to a gap between the processing container chamber and the inner container.

Further, a step of removing reaction products generated in the step of processing the semiconductor substrate and adhering to the interior of the processing chamber by washing with a chemical containing pure water or moisture, and after the washing is completed, exhausting the interior of the processing chamber. And a step of exhausting a gap sandwiched between the processing container chamber and the inner container by a vacuum line and a bypass line.

Further, a step of processing the semiconductor substrate, a step of removing reaction products generated in the processing step and adhering to the inside of the processing container chamber by cleaning using a chemical containing pure water or moisture, and after the cleaning is completed, After the process of evacuating the container chamber, the process of closing the main exhaust valve of the process chamber and the exhaust valve of the vacuum line or bypass line, and introducing an inert gas from the purge gas introduction line to bring the process chamber to a desired pressure, A step of closing an exhaust valve of a purge gas introduction line, and a step of opening a main exhaust valve and an exhaust valve of a vacuum line and a bypass line, and exhausting a gap between the processing container chamber and the inner container and the processing container chamber for a predetermined time. And a series of these steps is repeated a plurality of times.

Further, the semiconductor processing apparatus of the present invention is used.

Further, after the cleaning of the present invention is performed, the semiconductor substrate is processed.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 First Embodiment A first embodiment of the present invention will be described for a case of a dry etching processing apparatus using microwave plasma.

FIG. 2 shows a series of flows from the processing of the semiconductor substrate to the cleaning and the restart of the processing in the first embodiment. Hereinafter, Embodiment 1 will be described with reference to this flowchart. In the figure, 101 to 106 are respectively
Corresponds to each step of etching, process check, periodic cleaning, evacuation and microwave introduction, vacuum performance check, and process restart.

First, an ordinary etching process using this apparatus, for example, an etching process (101) of a polysilicon film on a semiconductor substrate using chlorine gas plasma will be described. FIG. 7 is a conceptual diagram for explaining a cross section of the etching apparatus and an etching process in the etching process.

In FIG. 7, 1 is a semiconductor substrate, 2 is a stage on which the semiconductor substrate 1 is mounted, 3 is a processing chamber,
4 is a plasma generation chamber of the processing chamber 3 and 5 is a processing chamber 3
6a is an inner container in the plasma generation chamber 4;
b is an inner container in the reaction processing chamber 5, 7 is a connecting part for connecting the inner containers 6a and 6b, 8a and 8b are gaps between the inner wall surface of the plasma generation chamber 4 and the inner container 6a, 8c Is a gap between the inner wall surface of the reaction processing chamber 5 and the inner container 6b;
9 is a corner portion of the processing chamber 3, 3 is a main exhaust pipe, 1
2 is a gas inlet, 13 is a process gas, 15 is a microwave oscillator, 16 is a microwave waveguide, 17 is a microwave introduction window, 18 is a microwave, 19c is a plasma discharge,
2 is a reaction product, and 24 is a reactive particle in the plasma.

The present apparatus has a main body of a processing vessel chamber 3 comprising a cylindrical plasma generation chamber 4 and a rectangular reaction processing chamber 5 in which a semiconductor substrate 1 is processed below.
A stage 2 on which the semiconductor substrate 1 is mounted and a inner container 6a or 6b are arranged in the lower central portion of the reaction processing chamber 5 so as to cover the inner wall surfaces of the plasma generation chamber 4 and the reaction processing chamber 5. Further, a microwave oscillator 15 for generating microwaves, a microwave waveguide 16 and a microwave introduction window 17 are arranged in the upper central portion of the plasma generation chamber 4.
Further, a gas inlet 12 for introducing the process gas 13 is provided below the plasma generation chamber 4, and a main exhaust pipe 11 for exhausting the gas is provided below the reaction processing chamber 5.

Next, the operation of the etching process will be described.
A chlorine gas, which is a process gas 13, is supplied from the gas inlet 12 into the processing chamber 3, and the processing chamber 3 is controlled to a constant low pressure by a pressure control mechanism (not shown). next,
The microwave 18 generated by the microwave oscillator 15 and introduced through the microwave waveguide 16 and the microwave introduction window 17 into the processing chamber 3 controlled to a constant low pressure.
And a magnetic field generated by an external coil (not shown) interacts with the plasma generation chamber 4 to generate a plasma discharge 19c.
Generate. The generated plasma discharge 19c is:
Since it diffuses into the reaction processing chamber 5 and has a plasma region as schematically shown in FIG. 7, it is difficult for plasma to be exposed to the corner portions 9 and the like of the processing container chamber 3. The plasma is basically not exposed to the gap 8 interposed therebetween.

The etching is performed by a chemical reaction between the polysilicon on the semiconductor substrate 1 exposed to the plasma discharge 19c and the reactive particles 24, for example, active chlorine atoms (Cl) generated during the discharge. Silicon is desorbed from the semiconductor substrate 1 as a reaction product 22 such as silicon chloride (SiCl), and is discharged to the outside of the apparatus through the main exhaust pipe 11 and removed.

However, when such an etching process is repeated, a large amount of the reaction product 22 diffuses from the surface of the inner container 6, the connecting portion of the connecting part 7, and the gap between the gas inlets 12 and enters the gap 8. Adhere to and accumulate on the surface. As a result,
The adhered and deposited reaction product 22 is re-adhered to the semiconductor substrate 1 during the etching process to deteriorate the etching performance, or if the deposited reaction product 22 exceeds the adhesion limit, it is peeled off to cause particles. For example, the reliability of the semiconductor device is significantly reduced. Therefore, in order to prevent such troubles beforehand, as shown in FIG. 2, every time the semiconductor substrate is processed for a certain period of time, the process performance such as an etching rate and particles is checked (102). Performs the cleaning (103) described below.

In order to perform cleaning, first, the processing container chamber 3 which is normally kept in a vacuum state during processing is once opened to the atmosphere, and the inner containers 6a and 6b, the connection parts 7, and the like are taken out.
Then, the reaction product 22 adhered and deposited on the surface of the removed component, the inner wall surface of the processing chamber 3, the stage 2, and the like.
Is carefully removed using chemicals such as pure water or boiling water containing a large amount of water. The detachable inner containers 6a, 6b, etc.
Further, it is desirable to bake in a baking facility or the like to remove residual moisture as much as possible. After the cleaning, the inner container 6 and the like are immediately incorporated into the processing container chamber 3, and then the processing container chamber 3 is evacuated from the main exhaust pipe 11.

FIG. 1 is a conceptual diagram illustrating a method of heating residual moisture 14 by microwaves in the present embodiment together with a cross section of a dry etching processing apparatus using microwave plasma of FIG. In the figure, reference numeral 14 denotes water remaining in the processing chamber. Other symbols are the same as those in FIG.

The microwave oscillator 15 is supplied to the inside of the processing chamber 3 where the cleaning is completed and the evacuation is started from the main exhaust pipe 11.
Is introduced into the plasma generation chamber 4 through the microwave waveguide 16 and the microwave introduction window 17 without introducing any process gas (1).
04). The energy of the introduced microwave 18 is efficiently absorbed by the residual moisture 14 and heated. The residual moisture 14 that has absorbed the energy can be easily desorbed from the inner wall surface of the processing container chamber 3 and the surface of the inner container 6 and the main exhaust pipe 1
It is discharged out of the device through 1 and removed.

This embodiment is characterized in that moisture is heated only by microwaves. That is, the introduced microwave 18 uniformly propagates throughout the chamber irrespective of the shape of the processing vessel chamber 3 and the arrangement of the inner container, so that the corner portions 9 and the gaps which could not be sufficiently heated by the conventional plasma discharge. A sufficient heating effect can be obtained also in the portion 8.

Next, after the cleaning method using the microwave 18 has been performed for a predetermined time, the pressure in the processing chamber 3 is measured. If the pressure has not reached the specified pressure, the cleaning using the microwave 18 is further performed for a predetermined time ( 105), if reached, the etching process is restarted (106).

In this embodiment, microwaves are introduced after vacuuming after cleaning, but the same effect can be obtained by introducing microwaves first at atmospheric pressure before vacuuming. Can be

According to the present embodiment, the microwave 18 propagates evenly to the corner 9 and the gap 8 of the processing chamber 3 which are not exposed to the plasma discharge due to the nature thereof. In comparison with the method using the external heater or the method using an external heater, the residual moisture 14 can be uniformly and efficiently heated over the entire inside of the processing chamber 3.

When the microwave 18 is introduced into the processing chamber 3, the pressure in the processing chamber 3 is reduced until the plasma reaches a low pressure of about 10 ⁻⁴ Torr by a conventional plasma discharge method. In contrast to the fact that discharge could not be performed and that it took a considerable time to reach this low pressure, in the present embodiment, microwaves can be introduced irrespective of pressure. Immediately after the heating, the residual moisture 14 can be heated, and the downtime of the apparatus can be greatly reduced.

Further, in the processing chamber 3 immediately after the cleaning, the microwave 18 acts mostly only on the residual water molecules 14, and the base material of the processing chamber 3 is usually made of metal. The conductor does not significantly increase its temperature, and also has the effect of preventing the processing container chamber 3 from being deformed by thermal stress.

Embodiment 2 In FIG. 1, a quartz material is usually used for the inner container 6 in the processing container chamber 3, but in the present embodiment, a dielectric material having a dielectric loss larger than that of quartz, such as barium titanate, is used. (B
By using the inner container 6 made of ceramics containing aTiO ₃ ) as a main component, the moisture 14 remaining in the inner container is reduced.
Can be further increased in heating efficiency.

The dielectric loss is caused by the fact that when an AC electric field is applied to the dielectric, the polarization of the dielectric cannot follow the change in the electric field, and the electric flux density causes a phase delay with respect to the electric field.
The energy of this loss is generally released as heat, and the residual moisture 14 absorbs this heat to increase the heating efficiency. Therefore, as compared with the first embodiment, downtime until the vacuum performance reaches a certain level can be further reduced.

In this embodiment, the inner container is made of a dielectric material having a dielectric loss larger than that of quartz.
The same effect can be obtained by coating a surface of an inner container made of a usual quartz material with a dielectric material having a large dielectric loss.

Embodiment 3 In the second embodiment, the inner container 6 made of a dielectric material having a dielectric loss larger than that of quartz is provided. However, in the present embodiment, as shown in FIG. 8a, 8b or 8c interposed between the inner wall surface of the container and the inner container 6a or 6b
Dielectric material 2 whose dielectric loss is larger than that of quartz
6. For example, a ceramic material containing barium titanate (BaTiO ₃ ) as a main component is provided. In addition,
FIG. 3 is a conceptual diagram illustrating a cross section of the dry etching apparatus using the same microwave plasma as in FIG. 1 and a process of heating water in the present embodiment.
Is the same as

Since the gaps 8 are narrow, the exhaust efficiency is generally low, and the water 14 remaining in these gaps cannot be sufficiently exhausted only by exhausting from the main exhaust pipe 11. But,
If the dielectric material 26 having a dielectric loss larger than that of quartz is disposed in the gap 8, the residual moisture 14 absorbs heat energy due to the dielectric loss and promotes desorption, and thus the gap 8 having a low exhaust efficiency is provided.
Also, the removability of the residual moisture 14 can be improved.

Embodiment 4 FIG. 4 is a conceptual diagram illustrating a cross section of a dry etching apparatus using microwave plasma similar to that of FIG. 1 and a method of removing residual moisture after cleaning according to the fourth embodiment. In the figure, 28 is a vacuum line, 29 is a turbo molecular pump, 30 is a valve, 31
Is a bypass line, 32 is a valve, and 36 is an opening of the inner container 6b. Other symbols are the same as those in FIG.

If necessary, the processing chamber 3 which has been cleaned is evacuated from the main exhaust pipe 11. Even during the evacuation, residual moisture 1 is removed from the interior of the processing chamber 3.
4 is always desorbed and removed. However, in a narrow portion such as the gap 8, as described above, the exhaust efficiency is low and the residual moisture 1
Even if 4 is desorbed, it cannot be sufficiently removed only by exhausting from the main exhaust pipe 11.

Therefore, in the present embodiment, the gaps 8a and 8b are locally evacuated by the evacuation line 28 independently disposed in the gap 8a and the bypass line 31 communicating between the gap 8a and the gap 8c. This is to improve the removability of the water 14. The evacuation line 28 includes a turbo molecular pump 29 and a valve 30,
The valve 30 is opened and closed as necessary, and the gaps 8a and 8b
The residual water 14 desorbed in the step is directly discharged to the outside of the apparatus and removed. A valve 32 is also attached to the bypass line 31. The valve 32 is opened and closed as required, and the residual moisture 14 desorbed in the gaps 8a and 8b is once passed through the opening 35 of the inner container 6b.
Then, the air is exhausted to the outside, and then discharged to the outside of the apparatus through the main exhaust pipe 11 and removed.

Next, a specific operation in this embodiment will be described. First, after the cleaning, the processing chamber 3 is evacuated from the main exhaust pipe 11 with the valve 30 of the evacuation line 28 and the valve 32 of the bypass line 31 closed. Immediately thereafter or thereafter, the valve 28 and the valve 32 are opened, and the residual moisture 14 desorbed in the gaps 8a and 8b is exhausted for a certain time. After the evacuation, the vacuum performance such as the ultimate pressure in the processing chamber 3 is checked. If there is no problem, the valves 28 and 32 are closed and the processing is restarted.

According to the present embodiment, the removability of residual moisture 14 in gaps 8a and 8b having low exhaust efficiency is improved.
Downtime until a certain vacuum performance is achieved can be reduced.

Embodiment 5 FIG. FIG. 5 is a conceptual diagram illustrating a cross section of a dry etching apparatus using microwave plasma similar to that of FIG. 4 and a method for removing residual moisture after cleaning according to the fifth embodiment. In the figure, 27 is a valve of the main exhaust pipe 11, 33 is a purge gas line, 34 is a valve, and 35 is a purge gas. Other symbols are the same as those in FIG.

In this embodiment, the apparatus of the fourth embodiment is further provided with a purge gas introduction line, and the gap 8a is further increased by the purge gas introduced from the purge gas introduction line.
And 8b with improved removability of residual moisture 14.

A specific operation in the present embodiment will be described. After the cleaning is completed and the evacuation of the processing chamber 3 is started, when a certain degree of vacuum is reached, first, the main exhaust pipe 1
The first valve 27, the valve 30 of the evacuation line 28, and the valve 32 of the bypass line 31 are closed. Next, the valve 34 of the purge gas line 33 disposed in the gap 8b
Is opened and the purge gas 35 is introduced into the processing chamber 3 until the pressure reaches a predetermined pressure, and then the valve 34 is closed. next,
The valve 27 of the main exhaust pipe 11, the valve 30 of the evacuation line 28, and the valve 32 of the bypass line 31 are opened again to evacuate the processing chamber 3, particularly the purge gas 33 sealed in the gap 8 a for a certain time. When the evacuation is completed, the valve 27 of the main exhaust pipe 11, the valve 30 of the evacuation line 28, and the valve 32 of the bypass line 31 are closed again, and the same operation is repeated. Thereafter, when a certain vacuum performance is reached, the valves 30, 32 and 34 are closed and the process is resumed.

According to the present embodiment, gaps 8a and 8a
Since the purge gas 33 functions as a carrier gas for the residual moisture 14 by repeatedly evacuating the purge gas 33 sealed in b, the removability of the residual moisture 14 in the gaps 8a and 8b having low exhaust efficiency is further improved.

Embodiment 6 FIG. FIG. 6 is a conceptual diagram illustrating a cross section of a dry etching processing apparatus using microwave plasma similar to that of FIG. 1 and a method for removing a reaction product according to the sixth embodiment. In the figure, reference numeral 26 denotes a dielectric material having a large dielectric loss. Other symbols are the same as those in FIG.

In the present embodiment, the inside of the processing chamber 3 to which the reaction product 22 adheres by the processing of the semiconductor substrate 1 is
A microwave 18 is introduced to remove a reaction product. In the present embodiment, inner containers 6a and 6b are made of a dielectric material having a dielectric loss larger than that of quartz, for example, a ceramic material containing barium titanate (BaTiO ₃ ) as a main component, and have gaps 8a and 8b or 8c. Similarly, a dielectric material 26 having a large dielectric loss, for example, a ceramic material containing barium titanate (BaTiO ₃ ) as a main component is provided.
On the other hand, the reaction product is desorbed by the heat generated by the dielectric loss to improve the removability.

According to the present embodiment, since the microwaves 18 that propagate uniformly throughout the processing chamber 3 are used,
It is possible to uniformly and efficiently remove the reactive products 22 attached to the corner portions 9 that are hardly exposed to plasma and the portions of the gaps 8 that are hardly exposed as in the related art.

Further, since reactive plasma is not used unlike the prior art, there is an effect that the inner container is not worn out or damaged.

In each of the embodiments described above, the dry etching processing apparatus has been described as the semiconductor processing apparatus. However, the present invention is not limited to this, and the semiconductor processing apparatus such as a CVD apparatus or a sputtering apparatus may be used. It is also applied to a processing device.

[0069]

Since the present invention is configured as described above, it has the following effects.

Since the inner container made of a dielectric material having a large dielectric loss with respect to microwaves is arranged in the processing chamber, the introduction of microwaves allows the residual moisture remaining in the inner container after cleaning to be removed more efficiently. It can be removed and the maintenance time by cleaning can be reduced.

Further, since a dielectric material having a large dielectric loss with respect to microwaves is disposed in a gap between the inner wall surface of the processing container chamber and the inner container, the cleaning is performed by introducing microwaves. The remaining moisture in the gap can be more efficiently removed, and the maintenance time for cleaning can be reduced.

Further, since microwaves are used, residual moisture after cleaning can be uniformly and efficiently removed throughout the processing container chamber and the inner container regardless of the shape and arrangement of the inner container, and maintenance time for cleaning can be reduced. Can be shortened.

Further, since the evacuation line or the bypass line is provided in the gap having low exhaust efficiency independently of the main exhaust pipe, the residual moisture in the gap after cleaning can be more efficiently removed. Maintenance time due to cleaning can be reduced. .

Further, since the purge gas is sealed in the gap and the exhaust from the evacuation line and the bypass line is repeatedly performed, the moisture remaining in the gap can be more efficiently removed, and the maintenance time for cleaning can be reduced. be able to. .

In addition, by introducing microwaves, the reaction products adhered to the inside of the processing chamber can be uniformly and efficiently removed, and the reliability of the semiconductor device can be improved.

Further, an inner container made of a dielectric material having a large dielectric loss with respect to microwaves, and a gap between the inner wall surface of the processing container chamber and the inner container with a large dielectric loss with respect to microwaves. Since a semiconductor device is manufactured using a semiconductor processing device provided with a dielectric material, a highly reliable semiconductor device can be manufactured.

Further, since the semiconductor substrate is processed after using the cleaning method by introducing microwaves, a highly reliable semiconductor device can be obtained.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a cross section of a dry etching apparatus using microwave plasma and a method for heating residual moisture using microwaves according to Embodiments 1 and 2 of the present invention.

FIG. 2 shows a series of flows from processing of the semiconductor substrate to cleaning and restart of the processing in the first embodiment of the present invention.

FIG. 3 is a conceptual diagram for illustrating a cross section of a dry etching apparatus using microwave plasma and a method for removing residual moisture according to a third embodiment of the present invention.

FIG. 4 is a conceptual diagram illustrating a cross section of a dry etching apparatus using microwave plasma and a method of removing residual moisture after cleaning according to a fourth embodiment of the present invention.

FIG. 5 is a conceptual diagram illustrating a cross-section of a dry etching apparatus using microwave plasma according to a fifth embodiment of the present invention and a method for removing residual moisture after cleaning in the fourth embodiment.

FIG. 6 is a conceptual diagram illustrating a cross section of a dry etching apparatus using microwave plasma according to a sixth embodiment of the present invention and a method for removing a reaction product according to the sixth embodiment.

FIG. 7 is a conceptual diagram illustrating a cross section of a conventional dry etching apparatus using microwave plasma and an etching method.

FIG. 8 is a series of flowcharts from processing of a semiconductor substrate to cleaning and restart of processing in a conventional method using plasma discharge and an external heater.

FIG. 9 is a conceptual diagram illustrating a cross section of a conventional dry etching apparatus using microwave plasma and a method of removing water by plasma discharge and an external heater.

FIG. 10 is a conceptual diagram for explaining a cross section of a conventional dry etching apparatus using microwave plasma and a method for removing a reaction product in a dry cleaning process.

[Explanation of symbols]

Reference Signs List 1 semiconductor substrate, 3 processing chamber, 4 plasma generation chamber, 5 reaction processing chamber 6 inner vessel, 8 gap between processing chamber and inner vessel 9 corner portion of processing chamber, 11 main exhaust pipe,
14 Residual moisture 18 Microwave, 22 Reaction product, 26 Dielectric material with large dielectric loss 27 Main exhaust valve, 28 Vacuum line, 30
Vacuum line valve 31 Bypass line, 32 Bypass line valve 33 Purge gas line, 34 Purge gas line valve

Claims (10)

[Claims] 1. A microwave generator, a processing container chamber for processing a semiconductor substrate, and an inner container disposed in the processing container room and made of a dielectric material whose dielectric loss with respect to microwave is larger than quartz. A semiconductor processing device comprising: 2. The semiconductor processing apparatus according to claim 1, further comprising a dielectric material having a dielectric loss larger than that of quartz with respect to microwaves in a gap between the processing container chamber and the inner container. 3. A step of removing reaction products generated in the step of processing the semiconductor substrate and adhering to the inside of the processing container chamber by cleaning using a chemical containing pure water or moisture, and the processing container after the cleaning step is completed. A cleaning method comprising: a step of exhausting a chamber; and a step of introducing a microwave without introducing a process gas into the processing chamber. 4. A microwave generator, a processing chamber for processing a semiconductor substrate, an inner container disposed in the processing chamber, and sandwiched between the processing chamber and the inner chamber. A semiconductor processing apparatus, comprising: a vacuum line connected to a gap; and a bypass line communicating a gap between the processing container chamber and the inner container chamber with a desired position in the processing container chamber. 5. The semiconductor processing apparatus according to claim 4, further comprising a purge gas line for introducing a purge gas into a gap between the processing container chamber and the inner container chamber. 6. A step of removing a reaction product generated in a step of processing a semiconductor substrate and adhering to the inside of the processing chamber by washing with a pure water or a chemical containing water, and the processing vessel after the cleaning step is completed. A step of evacuating the chamber, a step of evacuating by a vacuum line connected to a gap between the processing vessel chamber and the inner vessel chamber, and a step of evacuating the processing vessel chamber and the inner vessel chamber. Exhausting air by a bypass line communicating with a desired position of the processing container chamber. 7. (a) a step of removing a reaction product generated in the step of processing the semiconductor substrate and attached to the inside of the processing chamber by washing with pure water or a chemical containing water;
(B) evacuating the processing chamber after completion of the cleaning step; (c) closing a main exhaust valve of the processing chamber and an exhaust valve of a vacuum line or a bypass line; and (d) a purge gas introduction line. (E) closing the valve of the purge gas introduction line, and (f) exhausting the main exhaust valve and the evacuation line or bypass line. Opening the valve and evacuating the gap and the processing chamber for a predetermined time, wherein the steps (c) to (f) are repeated a plurality of times. 8. A cleaning method, comprising: a step of processing a semiconductor substrate; and a step of introducing microwaves without introducing a process gas into a processing chamber. 9. A method for manufacturing a semiconductor device, comprising using the semiconductor processing apparatus according to claim 2 or 5. 10. A method for manufacturing a semiconductor device, comprising processing a semiconductor substrate after performing the cleaning according to claim 3, 7, or 8.