JP2003142460A - Plasma treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma treatment apparatus where strong uniform plasma treatment is conducted over a large area, plasma treatment in arbitrary distribution can be made, and apparatus costs are low. SOLUTION: A plurality of microwave generators are used, and microwaves are independently supplied into a chamber for generating plasma, thus easily adjusting plasma distribution. Additionally, a practically sufficient operation can be secured by a simple configuration without tuner. Further, the plasma distribution can be freely adjusted by providing the plurality of compact microwave generators, and plasma treatment having further uniform or specific distribution as compared with a conventional one can be conducted. In addition, by heating and controlling a plurality of systems of heaters independently, specific temperature distribution is given to a placed object to be treated, and the distribution of the plasma treatment of the object to be treated can be corrected.

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 more particularly to a plasma processing apparatus for processing an object to be processed using plasma generated by irradiating a process gas with a microwave in a vacuum chamber. .

[0002]

2. Description of the Related Art Dry etching using plasma,
Plasma processing such as ashing, thin film deposition, or surface modification is widely used in various industrial fields including semiconductor devices and liquid crystal display devices.

A typical example of an apparatus for performing such plasma processing is a microwave-excited plasma processing apparatus that generates plasma by microwaves.

FIG. 9 (a) is a schematic view showing a main structure of a plasma processing apparatus of a micro semiconductor excitation type. That is, in this plasma processing apparatus, the mounting table 104 is provided inside the chamber 101 capable of maintaining a vacuum, and the workpiece W is processed.
Are held on the mounting table 104. This chamber 1
An exhaust pump (not shown) and a gas supply source are connected to 01 to maintain a gas atmosphere 102 having a predetermined composition and pressure.

On the other hand, a power source 10 is provided outside the chamber 101.
A microwave generator 108 driven by 9 is provided, and a microwave is guided by a waveguide 106 via a microwave tuner 107. Microwave generator 108
The output power is usually about 1 kW (kilowatt) to 10 kW. The guided microwave is introduced into the chamber 101 from the slot 110 through the microwave transmission window 105.

FIGS. 9B and 9C show the slot 110.
It is a top view which illustrates the opening shape and arrangement of. Slot 1
10 has an elongated opening shape, and its opening shape and arrangement are devised so that a predetermined plasma distribution can be obtained.

The microwaves introduced into the chamber 101 excite the process gas to generate plasma in the vacuum chamber. In this way, active species are generated from the process gas and supplied to the surface of the object W to be processed, whereby plasma processing such as dry etching, ashing, and film formation can be performed.

Further, in this type of plasma processing apparatus, plasma generated inside the chamber 101 is brought into contact with the surface of the object W to be subjected to surface treatment such as etching and ashing with active species in the plasma. In some cases, the chamber is divided into a plasma generation region and a processing space, and the downflow from the plasma is guided to the surface of the object to be processed for surface treatment such as etching and ashing.

A dielectric material can be used as the material for forming the microwave transmission window 105 described above, and specifically, quartz, alumina, sapphire or the like can be used.

As the process gas for forming the plasma, for example, when etching a thin film on the surface of the object to be processed, oxygen gas (O ₂ ) or oxygen gas such as CF ₄ , NF ₃ or the like is used. A gas added with a fluorine-based gas can be used.

[0011]

By the way, in recent years, in the manufacturing process of semiconductor devices, liquid crystal display devices, and the like, the size of semiconductor wafers and glass substrates to be processed has been rapidly increased. In order to perform highly uniform plasma processing on such a large workpiece, it is necessary to realize a plasma distribution that matches the process conditions such as the chamber shape, gas flow, and pressure distribution. There is.

On the other hand, in the conventional plasma processing apparatus, usually, only one microwave generator is provided as the plasma excitation source. However, the distribution of plasma by the microwaves supplied from one microwave generator depends on the shape and size of the chamber in which the plasma is generated, the method of introducing the microwaves, the structure such as the shape and material of the transmission window, the microwaves. Depending on process conditions such as input power, flow rate of gas introduced into chamber, type, pressure distribution, etc.
It is often decided uniquely. At this time, when one mode is formed, a plasma having that distribution can be stably obtained, but this distribution is not always the optimum plasma distribution for the uniformity of the object to be processed. Even if an optimum plasma distribution with respect to uniformity is obtained, if the process conditions change, another mode often occurs, resulting in deterioration of uniformity.

Further, a plurality of modes may occur for a certain process condition. In such a case, since there are a plurality of plasma distributions, there are various distributions of uniformity, and problems of uniformity and reproducibility occur.

As described above, it is very difficult to produce a plasma distribution having excellent uniformity over a wide range of process conditions.

On the other hand, a structure in which a plurality of microwave transmission windows are provided in the chamber and microwaves are supplied from one microwave generator is also conceivable. However, in this case, it is very difficult to uniformly apply microwave power to all the transmission windows. That is, it is considered that in many cases, plasmas having different intensities are randomly generated corresponding to the plurality of microwave transmission windows, and the uniformity and reproducibility of the plasma are insufficient.

On the other hand, if the processing speed and the apparatus size are ignored, the uniformity of the processing is improved by enlarging the chamber and moving the object to be processed away from the plasma. However, this is not a realistic solution.

The present invention has been made on the basis of the recognition of such a problem, and an object thereof is to enable strong and uniform plasma treatment over a large area, and also to perform plasma treatment with an arbitrary distribution as required. An object of the present invention is to provide a plasma processing apparatus that can be manufactured at low cost.

[0018]

In order to achieve the above object, the first plasma processing apparatus of the present invention comprises a vacuum chamber capable of maintaining an atmosphere depressurized with respect to the atmosphere, and a first and a microwave generating chamber. A second microwave generator; first and second waveguides for guiding the microwaves generated by the first and second microwave generators to the vacuum chamber; and the first and second waveguides. A first impedance matching means and a second impedance matching means respectively provided in the two waveguides,
The microwave generated by the first microwave generator was introduced into the first region in the vacuum chamber through the first waveguide and was generated by the second microwave generator. Microwaves are introduced into the second region, which is not the same as the first region, in the vacuum chamber through the second waveguide, and the microwaves are introduced into the first and second regions, respectively. When the object to be plasma-processed by the plasma simultaneously generated by the wave, the first
And the distribution of the plasma is made variable by adjusting the balance of the intensities of the microwaves introduced into the second region.

According to the above construction, by adjusting the outputs of the two microwave generators, it is possible to perform a uniform plasma treatment over a large area, and it is also possible to provide a specific distribution.

Further, the second plasma processing apparatus of the present invention comprises a vacuum chamber capable of maintaining an atmosphere decompressed with respect to the atmosphere, and a microwave generator for generating a microwave. The microwave generated by the above substantially satisfies the resonance condition without passing through the impedance matching means, and the plasma generated by being introduced into the vacuum chamber enables plasma processing of the object to be processed. And

In general, when plasma is generated using microwaves, an impedance matching device called a tuner exists between the microwave generator and the discharge part via a microwave waveguide to perform impedance matching. Instead of this impedance matching, by optimizing the shape of the microwave waveguide and the shape of the discharge part such as the microwave transmission window to resonate, instead of impedance matching,
Microwaves can be efficiently supplied to plasma without using an impedance matching device.

Further, a third plasma processing apparatus of the present invention comprises a vacuum chamber capable of maintaining an atmosphere decompressed with respect to the atmosphere, and a plurality of microwave generators for generating microwaves. The plasma generated by each of the microwave generators is introduced into different regions in the vacuum chamber without passing through the impedance matching means, and the plasma is simultaneously generated by the microwaves introduced into the respective different regions. When the plasma processing of the object to be processed is performed, the distribution of the plasma is made variable by adjusting the balance of the microwaves introduced into the different regions.

When plasma is generated over a wide range using one microwave generator, there are high plasma density and low plasma density. On the contrary, when plasma is generated in a narrow place, plasma is generated at the same position regardless of the hardware configuration such as the chamber and the process conditions, and the plasma density is affected only by the microwave input power. In this case, 1
If the microwave generator of the table is configured to generate a plurality of plasmas generated in a narrow range, a plasma generation place and a plasma generation place can be formed unless power of several tens kW or more is applied.

That is, when a plurality of plasmas generated in a narrow range are generated using a plurality of microwave generators, the intensity of each plasma is controlled by adjusting the output of each microwave power source. It will be possible. This is because by arranging a plurality of plasmas in a narrow range at a desired position and controlling the output of each microwave power source, a desired plasma distribution can be easily obtained regardless of hardware or process conditions.

Here, the microwave generated by at least any two of the plurality of microwave generators is introduced into the chamber through a common transmission window provided in the chamber. Can be

Further, the microwave balance can be adjusted by independently controlling each of the plurality of microwave generators by different control means.

In other words, when a plurality of plasmas are generated using a plurality of microwave generators and a desired plasma distribution is created, the intensity of each plasma can be individually controlled by attaching a power supply or output controller to all the generators. It becomes possible to easily generate plasma with various distributions. This is effective as a countermeasure when the chamber structure cannot be made symmetrical due to vacuum exhaust or conveyance of the object to be processed, or when the object to be processed is not symmetrical due to the influence of gas flow etc. Is.

Alternatively, at least any two of the plurality of microwave generators can be simultaneously controlled by common control means.

That is, when a plurality of plasmas are generated by using a plurality of microwave generators to create a desired plasma distribution, the output control of each generator is performed by one controller, which simplifies the microwave power supply equipment. It will be realized and equipment cost and space will be reduced.

When a plurality of plasmas are generated by using a plurality of microwave generators and a desired plasma distribution is created, the plasmas are usually arranged symmetrically with respect to the center of the chamber. At this time, by dividing each plasma into several groups and installing one output controller for each group, the microwave generator can be controlled efficiently and the simplification of microwave power supply equipment is realized. Cost and space are reduced.

On the other hand, a mounting table provided in the chamber for mounting the object to be processed is further provided.
If the temperature distribution of the object to be processed is made variable by adjusting the electric power supplied to each of the heaters of a plurality of systems, the deviation of the plasma distribution or the like can be corrected by the temperature distribution. You can

On the other hand, in the fourth plasma processing apparatus of the present invention, a vacuum chamber capable of maintaining an atmosphere decompressed with respect to the atmosphere, a microwave generator for generating a microwave, and a processing object provided in the chamber are provided. A mounting table on which an object is placed, and a plasma capable of performing plasma processing on the object to be processed by plasma generated by introducing microwaves generated by the microwave generator into the vacuum chamber. In the processing apparatus, the mounting table has heaters of a plurality of systems, and adjusts electric power supplied to each of the heaters of the plurality of systems to make the temperature distribution of the object to be processed variable. To do.

By independently controlling the heating of a plurality of heaters in this manner, a predetermined temperature distribution is given to the object to be placed, and the size and shape, the plasma distribution, the chamber shape and the process conditions are used. It is possible to correct the determined plasma processing distribution of the workpiece W.

Here, the mounting table is provided between a plurality of first portions surrounding each of the heaters of the plurality of systems and the plurality of first portions, and is more than the first portions. With the second portion having low heat conduction, a steep temperature distribution can be formed, and correction can be performed in a wider range.

In the present specification, "impedance matching means" means a variable adjuster which is provided between the microwave generator and the discharge part and whose impedance can be changed afterwards. Therefore, when the microwave generator is attached to the chamber, the attachment position, the length of the introduction portion, the inner diameter, etc. are adjusted so that the microwave generator is not the variable adjuster but the "impedance matching means" in the present specification. Is not applicable.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to specific examples.

(First Embodiment) First, the first embodiment of the present invention
As an embodiment of the above, a plasma processing apparatus provided with two microwave generators will be described.

FIG. 1 is a schematic view showing the main structure of the plasma processing apparatus according to this embodiment. That is, the plasma processing apparatus of this embodiment also has the chamber 1 capable of maintaining a vacuum. A mounting table 4 is provided inside the chamber 1,
An object W to be processed such as a semiconductor wafer or a glass substrate is held on the mounting table 4. An exhaust pump and a gas supply source (not shown) are connected to the chamber 1, and the gas atmosphere 2 having a predetermined composition and pressure is maintained. Also, the mounting table 4
Alternatively, the DC bias voltage or the high frequency bias voltage may be applied by the DC power source or the high frequency power source.

On the other hand, a pair of microwave excitation sources is provided outside the chamber 1. That is, two microwave generators 8A and 8B are provided, and the microwave M is guided by the waveguides 6A and 6B via the microwave tuners 7A and 7B, respectively. Here, the microwave generator 8
Each of A and 8B is, for example, 0.5 kW to several kW
It can have some output. The guided microwave is transmitted through the microwave transmission windows 5A and 5B to the chamber 1
Will be introduced in.

As a material for forming the microwave transmitting window 5, a dielectric material can be used, and specifically, quartz, alumina, sapphire or the like can be used. Further, as the process gas 2 for forming plasma, for example, when etching a thin film on the surface of an object to be processed, oxygen gas (O ₂ ) or fluorine gas such as CF ₄ or NF ₃ is used as oxygen gas. A gas added with a gas can be used.

Furthermore, the waveguides 6A and 6B may be provided at their tips with slots for emitting microwaves with a predetermined intensity and distribution.

The microwaves introduced into the chamber 1 through the transmission windows 5A and 5B excite the process gas 2 to generate plasma in the chamber 1. In this way, active species are generated from the process gas and supplied to the surface of the object W to be processed, whereby plasma processing such as dry etching, ashing, and film formation can be performed.

The plasma processing apparatus according to this embodiment has two
Microwave generators 8A, 8B and tuners 7A, 7
By using B, microwaves can be independently supplied to the chamber 1 to generate plasma. Generator 8
Each of A and 8B can be independently controlled by the power supplies 9A and 9B. Therefore, the plasma distribution can be easily adjusted by changing the outputs of the microwave generators 8A and 8B according to the size and shape of the object to be processed W or the process conditions. Therefore, the desired plasma distribution can be obtained over a wide range of process conditions, the uniformity of the plasma processing on the object W to be processed can be improved, or the plasma processing in which the desired distribution is intentionally provided can be performed.

(Second Embodiment) Next, the second embodiment of the present invention will be described.
As an embodiment of the present invention, a microwave-excited plasma processing apparatus having a simple structure without a tuner will be described.

FIG. 2 is a schematic view illustrating the configuration of the main part of the plasma processing apparatus according to this embodiment. In this figure, elements similar to those described above with reference to FIG. 1 are marked with the same reference numerals and not described in detail.

Generally, when plasma is generated using microwaves, an impedance matching device called a "tuner" is provided between the microwave generator and the discharge part via a microwave waveguide to perform impedance matching. Need to be adjusted. Instead of adjusting this impedance matching, by optimizing the shape and arrangement relationship of the microwave waveguide and the discharge part such as the microwave transmission window so that the microwave resonates, without providing an impedance matching device, It becomes possible to efficiently supply the microwave.

That is, in the present embodiment, the microwave emitted from the microwave generator 8 is guided to the transmission window 5 and introduced into the chamber 1 without interposing a tuner to generate plasma. I am trying. In this case, by providing a structure in which the microwave resonates in the section from the microwave generator 8 to the transmission window 5, the same effect as adjusting the impedance matching can be obtained.

When the resonance condition is deviated and some reflection occurs, it is also effective to add a cooling means to the generator 8. That is, simply the microwave generator 8
When the discharge section and the discharge section are connected by the waveguide 6, a part of the incident microwave may be reflected by the discharge section and returned to the microwave generator 8 as a reflected wave to be converted into heat. On the other hand, if the microwave generator 8 is provided with a cooling measure, the efficiency is lower than in the case where the impedance matching device or the ideal resonator structure is used. Can be used.

As described above, according to the present embodiment, it is possible to secure a practically sufficient operation with a simple structure without the tuner.

(Third Embodiment) Next, the third embodiment of the present invention will be described.
As an embodiment of the present invention, a plasma processing apparatus capable of forming an arbitrary distribution by combining the technical ideas of the first embodiment and the second embodiment described above and providing a plurality of low-power microwave generators will be described. To do.

FIG. 3 is a schematic view illustrating the configuration of the main part of the plasma processing apparatus according to this embodiment. That is, FIG. 7A is its sectional view and FIG. 7B is its plan view. In this figure, elements similar to those described above with reference to FIGS. 1 and 2 are marked with the same reference numerals and not described in detail.

In this embodiment, a plurality of small microwave generators 18 each having an output of several tens to several hundreds of watts are attached to the chamber 1, and each can be independently controlled by the power source 20 to generate plasma. There is. By providing a plurality of small microwave generators 18 in this way, it becomes possible to adjust the plasma distribution inside the chamber 1 arbitrarily and precisely, and depending on the size and shape of the object W to be processed, process conditions, or the like. Thus, plasma processing with a desired distribution can be performed.

Here, the small microwave generator 18 used in this embodiment is significantly different from the generator 108 in the conventional apparatus illustrated in FIG. 9 in terms of output and price. That is, the microwave generator 108 in the conventional device has an output of 1 kW (kilowatt) to 10 kW.
The price is about W, and the price is more than 3 million yen including the power supply. On the other hand, the small microwave generator 18 used in this embodiment has an output of several tens of watts (watts) to several hundreds of watts, which is exactly in the 2.45 GHz band used in a commercially available microwave oven. It is equivalent to a magnetron. The generator of this class including the power supply 20 is available at a very low cost, for example, about several thousand yen.

That is, the plasma processing apparatus according to the present embodiment can freely form various plasma distributions, which has been impossible in the past, by utilizing a magnetron for a microwave oven which is widely available. It also has the advantage that the device cost is extremely low.

Furthermore, in the present embodiment, FIG.
The tuner 107 as illustrated in FIG. 4 may be unnecessary. That is, the small microwave generator 1 with a small output
It is sufficient to secure a predetermined impedance matching when mounting the device 8. Even if some loss such as a reflected wave occurs, the amount of heat generated is small, and the number of small microwave generators 18 is increased. , The loss can be easily compensated.

Here, with respect to the number and arrangement of the small microwave generators 18 attached to the chamber 1, various modifications other than those shown in FIG. 3 can be similarly adopted.

Furthermore, the present invention can be similarly applied to a so-called "downflow type" plasma processing apparatus in which the plasma generation space and the plasma processing space are separated.

FIG. 4 is a schematic view illustrating the configuration of the main part of the downflow type plasma processing apparatus according to this embodiment. In the case of this specific example, the chamber 1 has a plasma generation space 1A and a plasma processing space 1B. The small microwave generator 18 is attached to the plasma generation space 1A, and the processing target W is placed in the plasma processing space 1B.
The plasma P generated with a desired distribution in the plasma generation space 1A is confined in the plasma generation space 1A by the magnetic field generated by the magnet 14, for example, and damage to the object W to be processed by charged particles such as ions and electrons is suppressed. can do. On the other hand, active species such as radicals contained in plasma, gas decomposition reaction products, and the like are supplied to the surface of the object W to be processed, and predetermined plasma processing such as etching or film formation can be performed. The space between the plasma generating space 1A and the plasma processing space 1B may be farther than that shown in the figure, or a partition having one or a plurality of openings may be provided between them.

According to the present embodiment, even in such a downflow type plasma processing apparatus, the distribution of plasma in the plasma generation space 1A can be arbitrarily adjusted, and the active species supplied to the object to be processed W and the like. The distribution of decomposition reaction products can be controlled. As a result, it is possible to realize a plasma treatment having a uniform or predetermined distribution.

On the other hand, in the present embodiment, various modifications can be adopted in the number and arrangement of the microwave transmitting windows 5 as well as the arrangement of the small microwave generator 18.

FIG. 5 is a schematic diagram showing a modification of the microwave transmitting window. That is, FIG. 1A is a cross-sectional view showing a plasma processing apparatus in which a plurality of small microwave generators 18 are provided on the upper surface of the chamber 1 according to this embodiment. Further, FIGS. 6B to 6D are plan views showing the microwave transmission window 5 provided on the upper surface of the chamber.

FIG. 5B shows a small microwave generator 18
A specific example in which an independent transmission window 5 is provided for each of the above will be described. As described above, when the independent transmission window 5 is provided, it is advantageous in that interference between the adjacent small microwave generators 18 can be suppressed.

On the other hand, FIG. 5C shows a specific example in which a single transmission window 5 is provided. When the single transmission window 5 is provided in this way, it is advantageous in that the configuration is simple and the number and arrangement of the small microwave generators 18 can be flexibly changed.

Further, FIG. 5D shows a concrete example in which the microwave introduction part is divided into a plurality of transmission windows. When the concentric annular transmission window is formed as shown in the figure, the advantage that the symmetry of the formed plasma is excellent can be obtained. Also,
Also in this case, the number and arrangement of the small microwave generators 18 can be adjusted.

By the way, in the present embodiment, a plurality of small microwave generators 18 may be controlled by one controller.

FIG. 6 is a schematic view showing a specific example of the plasma processing apparatus which systematically controls in this way. In the case of this specific example, a plurality of microwave generators 18 attached to the chamber are connected to the chamber central portion 18A and the chamber outer peripheral portion 18A.
B and chamber side surface portion 18C are divided into three groups. Then, for each of these groups, the controller 20
It can be controlled independently by A, 20B, and 20C.

Generally, in order to improve the uniformity of the plasma processing on the object W to be processed, it is effective to form a concentric ring plasma. Then, the plasma density is set to be the same in the circumferential direction, and the intensity of the microwave is provided in the radial direction to generate the plasma, whereby the uniformity can be optimized. That is, the generators 18 in the group
Since the microwave intensities of can all be the same,
Control is possible with one controller for each group.
At this time, the controllers 20A to 20C may simply send the output signal to the power source, or may supply a predetermined power source output to the generator 18.

As described above with reference to the specific examples, according to the present embodiment, the plasma distribution can be freely adjusted by providing the plurality of small microwave generators 18, which is far more than the conventional one. It is possible to perform a plasma treatment having a uniform or predetermined distribution. Moreover, the cost of the apparatus can be made lower than that of the conventional plasma processing apparatus.

(Fourth Embodiment) Next, the fourth embodiment of the present invention will be described.
As an embodiment of the present invention, a plasma processing apparatus equipped with a mounting table suitable for performing a plasma processing on the object W to be processed with a uniform or predetermined distribution will be described.

In the case of the conventional plasma processing apparatus as illustrated in FIG. 9 as well as the plasma processing apparatus described above with respect to the first to third embodiments, the mounting table 4 (104) on which the object W to be processed is mounted. Is a case where it is necessary to cool the object W with respect to heat received by the object W from plasma or reaction heat generated during plasma processing, or conversely, the temperature of the object W is positively set. May be increased to increase the processing speed. In these cases, it is desirable that the temperature distribution on the surface of the mounting table 4 be designed to be uniform in order to improve the uniformity of the object W to be processed.

In order to increase the size of the object W to be processed and to perform plasma processing with excellent uniformity over the entire surface,
A plasma distribution that suits the chamber shape and process conditions is required. The plasma processing of the workpiece W is performed by, for example,
The process gas is excited in the plasma to become an active species, which causes a reaction on the surface of the object to be processed W to proceed. However, the processing rate is determined by various factors such as the distribution of generated plasma, the life of the active species, the gas flow due to the shape of the chamber and the deactivation of the active species on the wall surface. According to the first and second embodiments, it is easy to form a uniform or point-symmetrical microwave distribution over the entire surface of the object to be processed W.

When such a microwave excitation source and an axially symmetric chamber are simply combined,
The velocity distribution of the plasma processing within the surface of the object to be processed W is a concave or convex distribution. Therefore, in the first and second embodiments, it is possible to perform uniform plasma processing over the entire surface of the object W to be processed by further adjusting the microwave distribution.

On the other hand, in this embodiment, the object W to be processed is provided by giving the mounting table 4 a unique configuration.
Enables uniform plasma treatment over the entire surface of the.

FIG. 7 is a schematic diagram showing a main part of the plasma processing apparatus according to this embodiment. That is, FIG.
Represents the whole structure thereof, and FIG. 1B is a perspective view showing the structure of the main part of the mounting table. Further, FIG. 7C is a perspective view showing a main part structure of the mounting table of the comparative example. Also in this figure, elements similar to those described above with reference to FIGS. 1 and 2 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the case of the specific example shown in FIG. 7A, the slot 10 (11) formed at the tip of the waveguide 6 (106).
0) microwaves are introduced into the chamber 1 through the transmission window 5 (105) and plasma of the process gas is formed.

Then, as shown in FIG. 7B, the mounting table 4 has a stage 40 for holding the object W to be processed and heaters 41 to 43 provided therein. Each of the heaters 41 to 43 is formed in a substantially concentric circle shape, and each temperature can be independently controlled. That is, by adjusting the electric power applied to the heaters of the respective systems, it is possible to provide a desired temperature distribution within the surface of the object W to be processed.

On the other hand, the mounting table 104 of the comparative example illustrated in FIG. 7C has only one heater 141. Therefore, the in-plane temperature distribution cannot be adjusted.

Generally, the speed of the plasma processing on the object W to be processed changes sensitively with temperature. That is, when the temperature of the object to be processed W is high, the plasma processing speed tends to be high, and when the temperature of the object to be processed W is low, the plasma processing speed tends to be low. Therefore, when the velocity distribution of the plasma processing has a concave distribution in which the object W has a minimum distribution at the center, the processing speed can be increased by providing a temperature distribution that maximizes the temperature of the mounting table 4. Can be made uniform over the entire surface. Conversely, the velocity distribution of plasma processing is
When the workpiece W has a convex distribution that has a maximum in the center, the processing speed can be made uniform over the entire surface by providing a temperature distribution in which the temperature of the mounting table 4 has a minimum in the center. .

In the case of the mounting table 4 shown in FIG. 7 (b),
By independently controlling the heating of the heaters 41 to 43 of the three systems, a predetermined temperature distribution is given to the placed workpiece W,
Object W determined by size and shape of object W, plasma distribution, chamber shape, process conditions, etc.
The plasma processing distribution can be corrected.

FIG. 8 is a schematic diagram showing a modified example of this embodiment. That is, FIGS. 3A and 3B show the mounting table 4
3 is a partial cross-sectional perspective view showing the structure of FIG.

In the case of the specific example shown in FIG. 8A, the concentric heat shield 45 is inserted between the three systems of heaters 41 to 43 provided concentrically. That is, by dividing the mounting table 4 into concentric circles and providing the heat shield 45 between the heaters, it is possible to further increase the temperature difference between the heaters and form a steep temperature distribution. As a result, the range in which the plasma distribution can be corrected is further expanded. That is, even when the plasma processing has a high non-uniformity, it is possible to make the processing speed uniform by providing a steep temperature distribution.

As the material of the heat shield 45 in this example, a material having a lower thermal conductivity than the stage 40 containing the heaters 41 to 43 can be used. For example, the stage 40 is made of alumina (Al ₂ O _3). ), The heat shield 45 can be made of quartz or macor. If the stage 40 is made of boron nitride (BN), the heat shield 45 can be made of silicon nitride (SiN). _x ) or alumina.

On the other hand, in the case of the concrete example shown in FIG.
A concentric gap 46 is formed between the three systems of heaters 41 to 43 provided concentrically. Since the plasma treatment is performed in a reduced pressure atmosphere, the propagation of heat in the gap 46 is substantially limited to radiation. Therefore, by dividing the mounting table 4 into concentric circles and providing the gap 46 between the heaters, it is possible to further increase the temperature difference between the heaters and form a steep temperature distribution. As a result, as in the case of FIG. 8A, the range in which the plasma distribution can be corrected is further expanded. That is, even when the plasma processing has a high non-uniformity, it is possible to make the processing speed uniform by providing a steep temperature distribution.

As described above, the mounting table 4 illustrated in FIGS. 8A and 8B may be used in the conventional plasma processing apparatus illustrated in FIG. 9, and the first to third embodiments of the present invention. It may be used for the plasma processing apparatus.

Further, the number of heaters in this embodiment is not limited to three. Furthermore, each heater 41-
The shapes of 43 and the heat shield 45 or the gap 46 are not limited to concentric circles, and may be various shapes suitable for adjusting the temperature distribution of the object W to be processed.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.

For example, in the present invention, the microwave transmission window 5 for transmitting microwaves does not necessarily have to be provided above the chamber 1, and a configuration provided on the side surface or below the vacuum chamber 1 is also applicable to the present invention. Included in the range.

Further, the chamber 1, the mounting table 4, the transmission window 5,
A configuration in which those skilled in the art can appropriately change the relationship between the shape and the size of each element such as the waveguide 6 and the like to obtain the effects of the present invention is included in the scope of the present invention.

Furthermore, in the above specific example,
Although only the main configuration of the plasma generation part has been described, the present invention
It is applicable to all plasma processing apparatuses having such a plasma generation unit, and for example, any plasma processing apparatus realized as an etching apparatus, an ashing apparatus, a thin film deposition apparatus, a surface processing apparatus, a plasma doping apparatus, etc. It is included in the scope of the invention.

[0090]

The present invention is carried out in the form described above and has the following effects.

First, according to the first embodiment of the present invention, by using two microwave generators and a tuner, microwaves are independently supplied into the chamber to generate plasma, so that the object to be processed is processed. The plasma distribution can be easily adjusted by changing the output of each microwave generator according to the size and shape of the object W or the process conditions. Therefore, the desired plasma distribution can be obtained over a wide range of process conditions, the uniformity of the plasma processing on the object W to be processed can be improved, or the plasma processing in which the desired distribution is intentionally provided can be performed.

Further, according to the second aspect of the present invention, it is possible to secure a practically sufficient operation with a simple structure excluding the tuner.

Further, according to the third aspect of the present invention, by providing a plurality of small microwave generators, the plasma distribution can be freely adjusted, and a much more uniform or predetermined distribution than that of the prior art can be obtained. It becomes possible to carry out the plasma treatment. Moreover, the cost of the apparatus can be made lower than that of the conventional plasma processing apparatus.

Furthermore, according to the fourth aspect of the present invention, the heaters of a plurality of systems are independently heated and controlled so that a predetermined temperature distribution is given to the object to be placed, its size and shape, and plasma. It is possible to correct the plasma processing distribution of the object W to be processed, which is determined by the distribution of the above, the chamber shape, the process conditions, and the like.

That is, according to the present invention, for example, when manufacturing a semiconductor device, a liquid crystal display device or the like, it is possible to perform a plasma treatment on a substrate having a larger area than ever before uniformly, quickly and at low cost, which is an industrial advantage. Is a great deal.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a main part structure of a plasma processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating the configuration of a main part of a plasma processing apparatus according to a second embodiment of the present invention.

FIG. 3 is a schematic view illustrating the configuration of a main part of a plasma processing apparatus according to a third embodiment of the present invention.

FIG. 4 is a schematic view illustrating the configuration of a main part of a downflow type plasma processing apparatus according to a third embodiment of the present invention.

FIG. 5 is a schematic diagram showing a modified example regarding a microwave transmission window. That is, FIG.
FIG. 3 is a cross-sectional view showing a plasma processing apparatus in which a plurality of small microwave generators 18 are provided on the upper surface of chamber 1. Further, FIGS. 6B to 6D are plan views showing the microwave transmission window 5 provided on the upper surface of the chamber.

FIG. 6 is a schematic diagram showing a specific example of a plasma processing apparatus that systematically controls a plurality of microwave generators.

FIG. 7 is a schematic diagram showing a main part of a plasma processing apparatus according to a fourth embodiment of the present invention.

FIG. 8 is a schematic diagram illustrating a modified example of the fourth exemplary embodiment of the present invention. That is, FIGS. 3A and 3B show the mounting table 4
3 is a partial cross-sectional perspective view showing the structure of FIG.

9A is a schematic view showing a configuration of a main part of a micro-semiconductor excited plasma processing apparatus, and FIGS. 9B and 9C are plan views illustrating the opening shape and arrangement of the slots 110. FIG. is there.

[Explanation of symbols]

1 chamber 1A Plasma generation space 1B Plasma processing space 2 process gas 4 table 5, 5A, 5B Microwave transmission window 6, 6A, 6B Waveguide 7A, 7B tuner 8,8A, 8B microwave generator 9, 9A, 9B power supply 10 slots 14 magnets 18 Compact microwave generator 20 power supplies 20A-20C controller 40 stages 41-43 heater 45 heat shield 46 Gap 101 chamber 102 gas atmosphere 104 mounting table 105 microwave transparent window 106 Waveguide 107 Microwave tuner 108 Microwave generator 109 power supply 110 slots 141 heater M microwave

Claims (9)

[Claims] 1. A vacuum chamber capable of maintaining an atmosphere decompressed with respect to the atmosphere, first and second microwave generators for generating microwaves, and generated by the first and second microwave generators. First and second waveguides for guiding the generated microwaves to the vacuum chamber
And a first impedance matching means and a second impedance matching means respectively provided on the first and second waveguides, and the microwave generated by the first microwave generator is provided. The microwave introduced into the first region in the vacuum chamber through the first waveguide and generated by the second microwave generator is vacuumed through the second waveguide. The object to be processed is plasma-processed by the plasma generated at the same time by the microwaves introduced into the second region which is not the same as the first region in the chamber and introduced into the first region and the second region, respectively. At this time, the plasma processing apparatus is characterized in that the distribution of the plasma is made variable by adjusting the balance of the intensities of the microwaves introduced into the first and second regions. 2. A vacuum chamber capable of maintaining an atmosphere decompressed with respect to the atmosphere, and a microwave generator for generating a microwave, wherein the microwave generated by the microwave generator is:
A plasma processing apparatus, wherein a resonance condition is substantially satisfied without passing through an impedance matching means, and plasma processing of an object to be processed is enabled by plasma generated by being introduced into the vacuum chamber. 3. A vacuum chamber capable of maintaining an atmosphere decompressed with respect to the atmosphere, and a plurality of microwave generators for generating microwaves, wherein microwaves generated by each of the plurality of microwave generators are provided. Waves are introduced into different regions in the vacuum chamber without passing through impedance matching means, and when plasma processing of the object to be processed by plasma simultaneously generated by the microwaves introduced into the respective different regions, A plasma processing apparatus, wherein the distribution of the plasma is made variable by adjusting the balance of the microwaves introduced into different regions. 4. The microwave generated by at least any two of the plurality of microwave generators is introduced into the chamber through a common transmission window provided in the chamber. The plasma processing apparatus according to claim 3, which is characterized in that. 5. By independently controlling each of the plurality of microwave generators by different control means,
The plasma processing apparatus according to claim 3, wherein the balance of the microwaves is adjustable. 6. The plasma processing apparatus according to claim 3, wherein at least any two of the plurality of microwave generators are simultaneously controlled by a common control means. 7. A mounting table, which is provided in the chamber and on which the object to be processed is mounted, further comprises a heater of a plurality of systems, and an electric power supplied to each of the heaters of a plurality of systems is provided. The plasma processing apparatus according to claim 1, wherein the temperature distribution of the object to be processed is variable by adjusting the temperature distribution. 8. A vacuum chamber capable of maintaining an atmosphere decompressed with respect to the atmosphere, a microwave generator for generating microwaves, and a mounting table provided in the chamber for mounting an object to be processed. A plasma processing apparatus capable of performing plasma processing of the object to be processed by plasma generated by introducing microwaves generated by the microwave generator into the vacuum chamber, wherein the mounting table is A plasma processing apparatus having a plurality of systems of heaters, wherein the temperature distribution of the object to be processed is made variable by adjusting the electric power supplied to each of the plurality of systems of heaters. 9. The mounting table according to claim 1, wherein a plurality of first portions surround each of the heaters of the plurality of systems, and a plurality of the first portions.
And a second portion which is provided between the portions and has a lower thermal conductivity than the first portion.
Alternatively, the plasma processing apparatus according to item 8.