JPH06291087A - Manufacture and manufacturing equipment of semiconductor integrated circuit device - Google Patents

Abstract

PURPOSE:To make etching and film formation uniform by irradiating a specimen with uniform plasma, and make possible especially enlarging the specimen diameter in dry etching, sputtering, and s CVD process. CONSTITUTION:The equipment is a microwave plasma process equipment wherein plasma is generated by mutual reaction of microwaves and a magnetic field and used for the dry etching process of a specimen surface, and consists of a specimen stand electrode 2 on which a wafer 1 is mounted, a counter electrode 3 which is arranged parallel with the electrode 2 and constitutes a flat plate, a vacuum vessel 4 for treating the wafer 1 with plasma, and a microwave generator 6 which supplies microwaves to the inside of a vacuum vessel 4 via a waveguide 5. The density and the energy of ions entering the wafer 1 are made uniform by the counter electrode 3, and particles emitted from the counter electrode 3 are effectively used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor integrated circuit device manufacturing technology, and more particularly to dry etching, sputtering and CVD in microwave plasma processing technology.
In the (Chemical Vapor Deposition) process, the production of a semiconductor integrated circuit device capable of satisfactorily responding to an increase in the diameter of a sample by irradiating the sample with uniform plasma by installing a counter electrode for the sample The present invention relates to a technique effectively applied to a method and a manufacturing apparatus.

[0002]

2. Description of the Related Art For example, in a semiconductor integrated circuit device manufacturing technique, as an etching device using a microwave plasma processing technique, as described in Japanese Patent Application Laid-Open No. 52-126175, except for a sample table electrode. There is a structure in which a decompression container made of quartz or alumina is used, and microwave power is transmitted from above the decompression container to generate plasma in the decompression container.

Similarly, as a technique relating to a microwave plasma etching apparatus, Japanese Patent Application Laid-Open No. 54-131476 has been proposed.
As described in the publication, a bias applying method for applying DC or AC power to the sample stage electrode is adopted, and an electrode other than the sample stage electrode for applying a fixed potential has a ring shape installed around the sample stage electrode. There is a method in which an electrode is used to apply an earth potential to control the energy of ions incident on a sample.

Further, as a sputtering apparatus using a microwave plasma processing technique, Japanese Patent Laid-Open No. 59-108523 is available.
JP-A-60-144670 and JP-A-60-209.
As described in Japanese Patent No. 911, a counter electrode structure for applying a bias from above the sample stage electrode is adopted, and a magnetic field coordination structure for confining plasma on the sample stage electrode by using a high frequency electric field from the outside is adopted. There is one in which the sputtering process of the generated film on the sample surface is performed in the cusp magnetic field.

[0005]

However, in the prior art as described above, for example, Japanese Unexamined Patent Publication No. 52-12617.
No. 5, JP-A-54-131476, the microwave is transmitted to the sample from above, and it is controlled by a ring-shaped electrode installed around the sample stage electrode. Differences easily occur between the center and the periphery, making it difficult to improve the uniformity of plasma conditions.
In particular, it is becoming more and more important to improve the uniformity of ion density and energy incident on the sample as the diameter of the wafer becomes larger.

That is, in the conventional microwave plasma etching technique, the plasma potential is kept at the ground potential,
RF (Radio Frequency) power is applied to the sample stage electrode to control the energy of the ions incident on the sample surface. In this case, in order to keep the plasma potential at the ground potential, it is provided around the sample stage. Plasma is brought into contact with the ring-shaped earth electrode so that the whole plasma has a value close to the earth potential, and the ion energy is controlled by the potential difference from the RF bias potential applied to the sample.

Therefore, when the area of contact of the plasma with the earth electrode is different, the plasma itself has a density distribution even if the contact area is the same, and when the resistance value of the plasma is high, the plasma potential depends on the distance from the earth electrode. Is not constant, and ion energy and the like are non-uniform in the periphery and center of the sample, and there is a problem that etching characteristics cannot be uniform.

Further, the devices described in JP-A-59-108523, JP-A-60-144670 and JP-A-60-209911 also have a cusp magnetic field even though an electrode facing the sample is provided. Therefore, plasma cannot be formed uniformly in the vicinity of the sample, and it is desired to improve the microwave transmission method and to construct a process for effectively utilizing particles emitted from the electrode material.

Therefore, when the material of the ground electrode is emitted by sputtering or chemical reaction, the influence of the emitted particles is different between the periphery and the center of the sample, so that the emitted particles cannot be effectively used. In particular, these phenomena are becoming remarkable as the sample becomes larger in diameter.

Therefore, an object of the present invention is to irradiate a uniform plasma on the sample by installing a counter electrode for the sample, and to make the etching and film formation uniform, particularly in the dry etching, sputtering and CVD processes. An object of the present invention is to provide a method and an apparatus for manufacturing a semiconductor integrated circuit device which can cope with a large diameter.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0012]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, the method and apparatus for manufacturing a semiconductor integrated circuit device according to the present invention is a method for manufacturing a semiconductor integrated circuit device in which plasma is generated by the interaction between a microwave and a magnetic field and a predetermined plasma treatment is performed on a sample. This is a technology, in which a counter plate is arranged in a parallel plate shape with respect to the sample stage electrode on which the sample is placed, and a counter electrode for generating a magnetic field in a direction perpendicular to the sample stage electrode between the sample stage electrode and the micro It is made of a ceramic material that allows microwaves to pass through on the wave input side, and the microwaves are transmitted from the microwave source to the space between the sample electrode and the counter electrode to generate plasma, which is then placed on the sample electrode. It is provided with a decompression container in which a predetermined plasma treatment is performed on the placed sample.

Furthermore, a first power source for supplying power to the microwave generation source, a second power source for supplying power to the sample stage electrode, and a third power source for supplying power to the counter electrode. Is provided.

In this case, the electric power supplied to the microwave source, the sample stage electrode and the counter electrode can be changed,
Further, the temperature of at least one of the sample table electrode and the counter electrode can be adjusted, and the magnetic field can be adjusted from the outside of the decompression container of at least one of the sample table electrode and the counter electrode.

[0016]

According to the above-described method and apparatus for manufacturing a semiconductor integrated circuit device, the counter electrode for the sample stage electrode and the decompression container for generating plasma by the microwave transmitted from the microwave generation source are provided. By making the distance between the counter electrode and the central portion and the peripheral portion of the sample uniform, the plasma uniformity can be improved. As a result, the entire surface of the sample can be uniformly irradiated with the particles generated from the ion density and ion energy in the plasma and the counter electrode material.

In addition, the microwave power source, the sample stage electrode, and the counter electrode are connected to the first, second, and third power sources whose power can be changed, so that the microwave power is supplied to the first power source. Since a desired combination can be freely set for the sample stage electrode and the counter electrode from RF power, DC power or ground potential, the degree of freedom can be improved according to the purpose of plasma processing, and not only etching but also
Sputtering and CDV processes can also be performed.

In this case, for example, the direction of introduction of the microwave into the decompression container is changed so that what is conventionally introduced vertically from above the decompression container into the sample is introduced from the side surface. An electrode can be provided above the decompression container, and the side wall of the decompression container must be made of a ceramic material such as quartz or alumina that can transmit microwaves in order to form plasma between the sample stage electrode and the counter electrode. It becomes possible by.

For example, in the microwave plasma processing apparatus having the counter electrode of the present invention, the main electric power for plasma generation is microwave, and the ion energy is controlled by applying the electric potential of the counter electrode which gives the plasma potential and the sample stage electrode. When the energy of ions entering the sample is increased, given from the relationship with the electric potential of the electric power, the electric power of the sample stage electrode is 400 kHz to 800 k, which is a relatively low frequency.
When using Hz and conversely controlling the energy of the ions to be low, it is effective to set the frequency to 13.56 MHz, which is a relatively high frequency, or the ground potential.

At this time, it is necessary for the counter electrode to be at the ground potential so as to keep the plasma potential as constant as possible. This means that when the same high frequency power is used, the peak voltage of the low frequency power is high. You can judge from that.
Therefore, it is also possible to keep the difference between the counter electrode and the sample stage electrode small by setting the frequency of the high frequency power applied to the sample stage electrode to the same level and matching the phases while the power is slightly low. It is desirable to select the frequency according to.

Further, when a process is constructed by releasing the electrode material of the counter electrode into the plasma by sputtering or chemical reaction, that is, in sputtering and etching, the particles of the electrode material released into the plasma act on the sample surface. By doing so, a good process can be constructed.

For example, what is important in sputtering is to use an electrode material of the same material as the film quality to be formed on the sample surface, and to carry out the emitted particles to the sample surface with good uniformity. On the other hand, in etching, for example, etching of a silicon oxide film is performed. Then, when the electrode material is silicon or carbon, highly selective etching is possible when the base material is silicon.

As described above, when the electrode material of the counter electrode is effectively used, it is important to select the material of the counter electrode and the high frequency power to be applied and the frequency thereof, which is naturally introduced into the decompression container. Combinations with process gases must also be considered.

The amount of the electrode material of the counter electrode supplied during the process and between the processes should be constant, and for that purpose, it is important that the temperature of the counter electrode is kept stable. Similarly, it is also necessary to keep the temperature of the sample stage electrode constant and keep the temperature of the sample placed on it constant.

As described above, the role of the parallel plate-shaped counter electrode in the sample stage electrode of the present invention is not only to improve the density of ions incident on the sample and the uniformity of ion energy, but also
It plays an important role in effectively utilizing the particles emitted from the counter electrode, and thus can be favorably applied to the large diameter of the sample in the plasma processing of the semiconductor integrated circuit device.

In particular, in the etching process, particles released by sputtering or chemical reaction can be effectively utilized to improve the etching rate, shape and selectivity which are the characteristics of dry etching, and in the sputtering process. It is possible to improve the sputtering rate and film quality of the formed film on the sample surface, which is a sputtering characteristic, and further to improve the deposition rate and film quality of the formed film on the sample surface, which is a CVD characteristic, in the CVD process.

[0027]

FIG. 1 is a side sectional view showing a microwave plasma processing apparatus which is an embodiment of a semiconductor integrated circuit device manufacturing apparatus of the present invention, and FIG. 2 is a plane sectional view showing a microwave plasma processing apparatus of this embodiment. FIG. 3 is a cross-sectional view of a semiconductor element showing a case where an oxide film is etched in the microwave plasma processing apparatus of this embodiment, and FIG. 4 is a semiconductor element when a through hole is opened in an interlayer insulating film of this embodiment. FIG. 5 is an explanatory view showing magnetic flux distribution characteristics in the microwave plasma processing apparatus of this embodiment.

First, the structure of the microwave plasma processing apparatus of this embodiment will be described with reference to FIG.

The microwave plasma processing apparatus of the present embodiment is a microwave plasma processing apparatus used in a dry etching process of a sample surface by generating plasma by interaction between a microwave and a magnetic field, for example, a wafer (sample). A sample table electrode 2 on which 1 is placed, and a counter electrode 3 which is arranged in parallel plate shape with respect to the sample table electrode 2,
A vacuum container (decompression container) 4 for performing a predetermined plasma treatment on the wafer 1 and a microwave generator (microwave generation source) 6 for transmitting microwaves inside the vacuum container 4 through a waveguide 5. Has been done.

A wafer 1 to be subjected to plasma processing is placed on the sample stage electrode 2, and electric power is applied from a high frequency power source (second power source) 7 connected to the sample stage electrode 2 to the wafer 1. The vertical electric field is generated between the counter electrode 3 and the plasma.

Further, the high frequency power source 7 can set the frequency according to the purpose of plasma processing or can be set to the ground potential, and the sample can be freely selected from the high frequency potential, the direct current potential and the ground potential. The potential of the base electrode 2 can be set. Further, a matching circuit (not shown) is provided between the high frequency power source 7 and the sample base electrode 2, and this matching circuit becomes unnecessary when the ground potential is set.

Further, the sample stage electrode 2 has a built-in refrigerant tank 8 and a heater 9 for controlling the temperature of the wafer 1 to be placed thereon, and the heater 9 and the cooling effect of liquid nitrogen in the refrigerant tank 8. The temperature is controlled by the combination of the heating effects by.

The counter electrode 3 is arranged in a position parallel to the sample base electrode 2, and the counter electrode 3 has the sample base electrode 2
The same high frequency power source (third power source) 10 is connected,
Depending on the purpose of plasma processing, it is possible to set the potential by freely combining high frequency potential, DC potential, and ground potential.

Further, the counter electrode 3 has a water cooling tube 11 for controlling the temperature therein, and the inner wall temperature of the vacuum container 4 may be room temperature, but the counter electrode 3 flows into the water cooling tube 11. The cooling water is always controlled to a constant temperature.

The side wall of the vacuum container 4 on the microwave input side is formed of a quartz ceramic material in a cylindrical shape and has a microwave permeable structure. And the vacuum container 4
In the depressurized state, the discharge gas is supplied from the gas introduction port 12 and discharged through the gas exhaust port 13.

Further, magnetic field generators 14 and 15 by permanent magnets or electromagnetic coils are provided outside the vacuum container 4, for example, outside the upper part of the vacuum container 4 and the position where the sample stage electrode 2 is disposed. The magnetic field generators 14 and 15 improve the plasma generation efficiency. Note that the magnetic field generators 14 and 15 are not always necessary because when the gas pressure is high, electric discharge occurs even without a magnetic field.

That is, since the magnetic fields generated by the magnetic field generators 14 and 15 are applied perpendicularly to the surface of the wafer 1 and are not necessarily orthogonal to the microwave electric field, an ideal ECR (Electron Cyclotron) is used. Resonance:
Although the electron cyclotron resonance) state cannot be achieved, it acts on electrons and ions in the plasma to prolong the staying period of the electrons and ions, thereby improving the plasma density.

Further, outside the vacuum container 4, a plasma emission lighting window 16 for light emission monitoring is provided on the side wall opposite to the microwave input side, and the plasma emission spectrum is transmitted through the plasma emission lighting window 16. Monitored,
The plasma state is controlled by the change in the etching rate and the like so that the desired etching is completed through the light emission monitor processing device 17.

The microwave generator 6 transmits microwaves to the inside of the vacuum container 4 through the waveguide 5 to generate plasma in the space between the sample stage electrode 2 and the counter electrode 3, and the sample stage electrode 2 A predetermined plasma process is performed on the wafer 1 placed on the upper part of the wafer.

Further, a microwave generation power source (first power source) 18 for applying microwave power is connected to the microwave generator 6, and main power for plasma generation can be supplied through the microwave generator 6. Like this,
Ion energy can be controlled from the relationship between the potential of the sample stage electrode 2 and the potential of the counter electrode 3.

The shape of the waveguide 5 is, for example, 2.45.
A standard rectangular waveguide for propagating a microwave of GHz is expanded to an inner diameter larger than the outer diameter of the sample stage electrode 2 through a tapered waveguide, and the vacuum container 4 is housed therein. ing.

Further, as shown in FIG. 2, a plurality of tuner rods 19 are attached to the inner wall portion of the waveguide 5, and in consideration of the case where the microwaves incident from the side wall of the vacuum container 4 are non-uniform. The wave motion of the microwave can be adjusted from the outside of the wall of the waveguide 5, and the tuner rod 19 is adjusted to improve the stability of microwave discharge and the uniformity of plasma.

Although not shown, the waveguide 5 is provided with an isolator and a power meter in the waveguide circuit of the waveguide 5, and controls the microwave and the microwave generator 6.
Helps in the stability of.

Next, regarding the operation of this embodiment, (1). Etching process, (2). Power control in etching process, (3). Temperature control in etching process, (4).
Magnetic field control in etching process, (5). Shape control in etching process, (6). CVD process, (7).
The sputtering process will be described in order.

(1). Etching Process First, as etching process conditions, for example, the microwave generation power source 18 is set to microwave power, the high frequency power source 7 of the sample stage electrode 2 is set to 800 kHz RF power, and the counter electrode 3 is set. The high frequency power source 10 is set to the ground potential, and the electrode material of the counter electrode 3 is silicon.

First, the vacuum container 4 has been evacuated in advance, and when the etching gas is introduced into the vacuum container 4 under reduced pressure, the vacuum container 4 is excited by microwaves.
Plasma is generated inside.

In this case, regarding the plasma uniformity, the distance between the vacuum vessel 4 and the waveguide 5, and the tuner rod 19
Adjustment is an important factor, especially the tuner bar 19
By adjusting the above, the nonuniform plasma wave can be effectively utilized to control the plasma uniformly.

Further, the reactive species in the generated plasma react with the wafer 1 and etching or deposition proceeds. In the present embodiment, the surface material of the wafer 1 is described as a silicon oxide film (SiO ₂ ), but even if it is a silicon substrate (Si), an aluminum film (A 2
Each of l) etching and the like has its own effect, but the SiO ₂ etching is particularly remarkable.

At this time, a mixed gas of C ₂ F ₆ and CHF ₃ is used as an etching gas for SiO ₂ . It goes without saying that the dry etching characteristics in this case depend on the gas species, the gas flow rate, the gas pressure, and the electric power of the microwave generating plasma.

Here, the flow rate of the C ₂ F ₆ gas is 40 cc.
/ Min, the flow rate of CHF ₃ gas is 50 cc / min, the gas pressure is 5 mTorr, and the microwave power is 600 W for plasma generation.

For example, in the conventional microwave etching apparatus, when the mixing ratio of CHF ₃ gas is set to about 70 to 80% when SiO ₂ is etched, the etching shape and the selection ratio of Si to the base material are 20 times. However, in the present embodiment in which the silicon material is used for the counter electrode 3, almost the same result as the conventional one can be obtained with the mixing ratio of 50 to 60%.

Such a result largely depends on the high frequency power of the high frequency power supplies 7 and 10 applied to the sample base electrode 2 and the counter electrode 3 and the respective temperatures, and is conventionally used when the high frequency power is optimized. The ratio of the deposition gas can be reduced, and the contamination in the device is reduced, so that the amount of particles generated can be reduced and the number of maintenance such as cleaning the inner wall of the device can be reduced.

[0053] For example, the dry etching of SiO ₂ (silicon oxide film), there is the case must be roughly divided into a thin oxide film with good uniformity etching, in the case of opening the through hole in the interlayer insulating film.

The former is a gate electrode 20 as shown in FIG.
Is a step of forming a thin oxide film 21 having a thickness of about 100 to 200 nm on the top surface and processing so that the oxide film 21 remains on the side wall of the gate electrode 20 after dry etching. Such processing is called LDD (Lightly Doped Drain).

In this LDD processing, since the oxide film 21 is thin, the etching uniformity and the selectivity with the Si substrate 22 as the base material are more important than the etching rate. Therefore, in the apparatus of this embodiment, it is effective to set the RF power applied to the sample stage electrode 2 as low as possible and control the ion energy to be uniform.

Further, in the apparatus of this embodiment, since Si as the electrode material of the counter electrode 3 is released, when the underlying Si substrate 22 appears at the etching end point, the Si particles 22 are released by the action of the released Si particles. Is difficult to be etched.

On the other hand, in the latter, as shown in FIG. 4, through holes 24 and 25 are opened in the interlayer insulating film 23, and the base electrode 2 is formed.
This is a process of ending the etching when the number reaches 6,27. Like the through holes 24 and 25 shown in the drawing, the interlayer insulating film 23 is often processed with different opening depths, and these must be processed at the same time.

In such processing, since the shallow through hole 24 reaches the processing end point in a short time, the deep through hole 25 is over-etched until the etching is completed. Therefore, it is important that the etching rate is high because the deep through hole 25 is opened first, and that the selection ratio is sufficiently large secondly. Further, as a third point, the shape of the deep through hole 25 is different. is important.

For example, the middle of the deep through hole 25 may have a bulged shape or may not reach the base electrode 27. There are many causes for this, but in particular, the shape cannot be controlled due to the directionality of ions and the deposition of neutral particles.

As described above, in the etching process of this embodiment, the principle of microwave plasma generation is that low gas pressure discharge is possible, and the plasma potential is the counter electrode 3.
Since the etching rate can be increased by increasing the RF power of the sample stage electrode 2 and the like, the controllability of ions is good, and the amount of particles emitted from the counter electrode 3 is also good. It can be favorably applied to the processing of the insulating film 23.

(2). Power Control in Etching Process In the above (1). Etching process, high-frequency power applied to the sample stage electrode 2 is 800 kHz and 120 W.
However, similar results can be obtained when other high frequency power of 13.56 MHz and 600 W is used.

That is, the power value differs depending on the applied frequency because the ions existing in the plasma are transferred to the wafer 1.
It is thought that this is because the accelerating voltage for making the surface of the slash different. Therefore, it goes without saying that it is necessary to set the power suitable for the frequency to be used.

Therefore, the higher the electric power, the higher the etching rate. However, if the power is too high, the etching rate of the mask material and the underlying material will be high, and the selection ratio will be deteriorated. On the contrary, if the power is too low, the processing time will be long. Therefore, it is desirable to set the values shown in this embodiment as the standard.

(3). Temperature Control in Etching Process In the above description, the temperature control of the wafer 1 is not strictly performed, and even if the sample stage electrode 2 is water-cooled, the wafer placed on the sample stage electrode 2 is controlled. The temperature of the wafer 1 often does not become constant due to plasma irradiation conditions because of insufficient thermal contact with the wafer 1.

However, in the apparatus configuration of the present embodiment, it is possible to make the sample stage electrode 2 below the water cooling temperature by the temperature control system by the combination of the liquid nitrogen in the refrigerant tank 8 and the heater 9. The same gas as the process gas is introduced between the base electrode 2 and the wafer 1 so as to maintain a relatively high gas pressure.

In this case, the vacuum container 4 other than the sample stage electrode 2
Although the inner wall temperature of the counter electrode 3 may be room temperature, it is necessary to keep the temperature of the counter electrode 3 constant, and a water-cooled electrode in which temperature-controlled cooling water is circulated in the water-cooled pipe 11 is used as the electrode surface of the counter electrode 3. When mounting the material as a thin plate material,
The thermal contact method using gas is adopted as in the case of performing thermal contact between the sample stage electrode 2 and the wafer 1.

Further, since the adsorption efficiency of various gases becomes high in the etching for lowering the temperature of the wafer 1, the flow rate and the pressure of the gas having a particularly high deposition property may be lowered. When the temperature is set to ° C, the same effect can be obtained even if both the flow rate and the pressure are lowered.

As described above, if the gas with high deposition property can be reduced, the contamination of the inner wall of the vacuum container 4 can be reduced, which is very advantageous as a semiconductor manufacturing apparatus. It goes without saying that they differ depending on the type.

Therefore, the amount of dirt on the inner wall of the vacuum container 4 is reduced to a necessary minimum, and the amount of dust generated in the apparatus is 30 to 50 when compared with the conventional dust amount of 0.3 μm or more.
The number of wafers / wafer is 5 in the apparatus of the present embodiment.
It can be drastically reduced to wafers. This is especially true for VLSI (Very Large
Scale Integrated Circuit), ULSI (Ultra LS
Since it is a fatal case of I), the effect of reducing the amount of dust generation is a very significant feature.

(4). Magnetic field control in etching process In the apparatus of this embodiment, the magnetic fields generated by the magnetic field generators 14 and 15 are applied perpendicularly to the surface of the wafer 1 and are not necessarily orthogonal to the microwave electric field. It cannot be said that the ideal ECR state because it can not be said that,
Since it acts on the electrons and ions in the plasma and makes it possible to prolong the residence time thereof, the plasma density can be improved.

For example, as shown in FIG. 5, the magnetic flux distribution in the vacuum container 4 is such that the magnetic flux distribution is constant over the width of the sample stage electrode 2 in the direction parallel to the sample stage electrode 2, and the sample stage electrode 2 is also obtained. The magnetic flux distribution in the vertical direction is maximized above the center of the sample stage electrode 2 and the counter electrode 3.

In this case, the maximum magnetic flux density (Bmax) in the direction parallel to and perpendicular to the sample stage electrode 2 is about 200-.
Sufficient processing is possible at 300 Gauss, which is about 8 times that of conventional etching processing with a ring electrode device.
Compared with 75-1.5K Gauss, it is possible to perform plasma processing with a low magnetic flux density of about 1/5.

Further, by adjusting the plurality of tuner rods 19 attached to the inner wall portion of the waveguide 5, even if the microwaves incident from the side wall of the vacuum container 4 are non-uniform, the microwaves from the outside of the vacuum container 4 can be adjusted. Since the wave motion of the wave can be adjusted, the stability of microwave discharge and the uniformity of plasma can be improved.

Therefore, regarding the uniformity of the plasma, the distance between the vacuum container 4 and the waveguide 5 and the adjustment of the tuner rod 19 are important factors, and the nonuniform plasma is controlled by optimally controlling these factors. The plasma can be uniformly adjusted by effectively utilizing the wave motion of

(5). Shape control in etching process For example, in dry etching of various metal silicide materials such as polycrystalline Si, Al, W, and Mo used as semiconductor element materials, normal dry etching is limited. Undercut conditions are likely to occur under other conditions.

That is, since etching proceeds with a radical reaction with respect to these materials, a sidewall protective film forming gas for protecting the sidewall being etched with a material which is difficult to be etched is used in order to etch the material into a vertical shape. It is necessary to use it.

Therefore, a gas containing BCl ₃ , SiCl ₄ , or C, which is a gas having a deposition property mixed with the etching gas, is used. Therefore, by using a material containing these components B, Si, and C for the counter electrode 3 and using a frequency and electric power suitable for each, it is possible to perform etching with good shape control.

As described above from (1). Etching process to (5). Shape control in etching process, in the etching process, it is possible to control the ion energy, which is difficult to control in the past, and the sputtering or chemical reaction is performed. Since the particles emitted from the counter electrode 3 can be effectively used, the etching rate, shape and selectivity, which are the characteristics of dry etching, can be improved, and the uniformity in etching can be improved.

(6). CVD Process In the above, an example of the etching process using C ₂ F ₆ and CHF ₃ gas has been described. Here, SiH ₄ gas and O ₂ gas for deposition were used. Si
The plasma CVD of O ₂ will be described.

As conditions for this CVD process, the electrode material of the counter electrode 3 is silicon (Si) or aluminum (Al), and the potential is earth potential. The high frequency power source 7 of the sample stage electrode 2 is 400 kHz and 50 W.

In this case, the power applied to the sample stage electrode 2 is set relatively high in order to perform bias sputter CVD instead of simple CVD. That is, the purpose is to perform flattening of the formed film by sputtering the formed film at the same time as forming the film. Furthermore, SiH ₄
Gas 12cc / min, O ₂ gas 120cc / mi
n, and the gas pressure is 3 mTorr.

For example, in the case of the conventional parallel plate type electrode, when high frequency power is used without microwave power, it is usual to use a high gas pressure of 1 to 10 Torr. Microwave power (about 4k
When W) is used as the main plasma source, the process can be built at gas pressures as low as about 3 orders of magnitude.

Regarding the uniformity of the film thickness of the formed SiO ₂ film, in the conventional microwave device, the periphery of the wafer 1 was thin. However, in this embodiment, the film thickness of the periphery should be formed with good uniformity. You can Further, the film formation time depends on the gas flow rate and the gas pressure, but the time can be shortened easily by changing the gas flow rate and the pressure setting without largely changing the high frequency power.

As a result, the CV in the apparatus of this embodiment is
In the D process, since the ion energy can be controlled and the particles emitted from the counter electrode 3 can be effectively used, C
It is possible to improve the deposition speed and the film quality of the formed film on the surface of the wafer 1 having the VD characteristic, and improve the uniformity in the film formation.

(7). Sputtering Process Here, the sputtering process which is another method of film formation will be described. For example, a predetermined electrode material such as tungsten (W) is used for the counter electrode 3 and 800
A high frequency power of 500 W at a frequency of kHz is applied, and the sample stage electrode 2 is set to the ground potential.

Further, the magnetic flux distribution in this case is the distribution perpendicular to the sample stage electrode 2 shown in FIG. 5, contrary to the case of the etching process, and the sample stage electrode 2 and the counter electrode 3 are opposite to each other.
The distribution characteristic is maximized below the central part of.

Then, as the process gas, argon gas (Ar) or oxygen gas (O ₂ ) or nitrogen gas (N ₂ ) is selected depending on whether the target film is an oxide film or a nitride film. A film can be formed by a sputtering process in the same manner as the process.

As a result, in the sputtering process in the apparatus of this embodiment, the ion energy can be controlled and the particles emitted from the counter electrode 3 can be effectively used. Therefore, the sputtering of the formed film on the surface of the wafer 1 which has the sputtering characteristic. It is possible to improve the speed and film quality and improve the uniformity in film formation.

Therefore, according to the microwave plasma processing apparatus of this embodiment, as described in (1). Etching process to (7). Sputtering process, it is arranged on the sample stage electrode 2 in a parallel plate shape. The counter electrode 3 not only improves the density of ions incident on the wafer 1 and the uniformity of ion energy, but also makes it possible to effectively use the particles emitted from the counter electrode 3, so that the uniformity in etching and film formation can be improved. In addition, it is possible to favorably apply to the large diameter of the wafer 1 in the plasma processing of the semiconductor integrated circuit device.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, in the microwave plasma processing apparatus of this embodiment, the case where the microwave input side of the vacuum container 4 is made of a ceramic material made of quartz has been described, but the present invention is limited to the above embodiment. However, it is widely applicable to materials that can transmit microwaves, such as alumina.

Further, in order to improve the stability of microwave discharge and the uniformity of plasma, the case where a plurality of tuner rods 19 are attached to the waveguide 5 has been described. The same effect can be obtained by using a plate-shaped rotating plate having a reflection effect.

Furthermore, it goes without saying that the temperature control function of the sample stage electrode 2 can be applied to any mechanism having a cooling effect and a heating effect, such as a combination system of a refrigerator and a heater.

[0094]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.
It is as follows.

(1). A counter electrode for the sample stage electrode on which the sample is placed, and a decompression container in which plasma is generated by the microwaves transmitted from the microwave source are provided, and the sample stage electrode and the counter electrode are provided. Between the counter electrode and the sample by performing a predetermined plasma treatment on the sample placed on the sample stage electrode by generating a magnetic field between the two and transmitting the microwave to the space to generate plasma. Since the distance between the central part and the peripheral part is uniform, and the uniformity of the plasma with respect to the sample surface can be improved, the ion density and ion energy in the plasma and particles generated from the counter electrode material are distributed over the entire sample surface. It is possible to uniformly irradiate.

(2). Microwave power is supplied to the first power source by connecting the first power source, the second power source, and the third power source capable of varying power to the microwave generation source, the sample stage electrode, and the counter electrode, respectively. Since, and the sample base electrode and the counter electrode can be freely set to a desired combination from RF power, DC power or ground potential according to the plasma processing type of the sample mounted on the sample base electrode. The degree of freedom can be improved according to the purpose of plasma processing, and etching, sputtering and CDV processes can be constructed.

(3) The temperature of at least one of the sample stage electrode and the counter electrode can be adjusted, and the temperature of the sample or the counter electrode placed on the sample stage electrode is controlled to a predetermined temperature, so that the etching temperature of the sample is controlled. Since the amount of the electrode material supplied to the counter electrode can be made constant, the density of ions incident on the sample and the uniformity of ion energy can be improved, and particles emitted from the counter electrode can be effectively used. Is possible.

(4). The magnetic field can be adjusted from the outside of the decompression container of at least one of the sample stage electrode and the counter electrode, and the staying period of the electrons and ions in the plasma is controlled so that the magnetic field is changed to the electrons and ions in the plasma. Since it is possible to increase the stay period by acting on the, the plasma density in the vacuum container can be improved.

(5) Due to the above (3), the adsorption efficiency of various gases becomes high and the flow rate of gas with high deposition property can be reduced especially in the etching process in which the temperature of the sample is low. It is possible to reduce the contamination of the sample and to minimize the influence of dust generation on the sample as a semiconductor integrated circuit device manufacturing apparatus.

(6). Due to the above (1), (3) and (4), it is possible to control the ion energy, which has been difficult to control conventionally, and to effectively utilize the particles emitted from the electrode. A microwave plasma processing technique capable of improving uniformity in film formation can be obtained.

(7) Due to the above (5), it is possible to reduce dust inside the device, which is important in the manufacturing process of the semiconductor integrated circuit device. In particular, it can be favorably applied to semiconductor integrated circuit devices such as VLSI and ULSI.

(8). Due to the above (1) to (7), the reliability of the semiconductor integrated circuit device is improved by uniforming etching and film formation particularly in the dry etching, sputtering and CVD processes in the microwave plasma processing technique. In addition, it is possible to obtain a plasma processing technique that can cope with the increase in the diameter of the sample.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a microwave plasma processing apparatus which is an embodiment of an apparatus for manufacturing a semiconductor integrated circuit device of the present invention.

FIG. 2 is a plan sectional view showing a microwave plasma processing apparatus of this embodiment.

FIG. 3 is a cross-sectional view of a semiconductor element showing a case where an oxide film is etched in the microwave plasma processing apparatus of this embodiment.

FIG. 4 is a cross-sectional view of a semiconductor element when a through hole is opened in an interlayer insulating film in the microwave plasma processing apparatus of this embodiment.

FIG. 5 is an explanatory diagram showing magnetic flux distribution characteristics in the microwave plasma processing apparatus of the present embodiment.

[Explanation of symbols]

 1 Wafer (Sample) 2 Sample Stand Electrode 3 Counter Electrode 4 Vacuum Container (Decompression Container) 5 Waveguide 6 Microwave Generator (Microwave Source) 7 High Frequency Power Supply (Second Power Source) 8 Refrigerant Tank 9 Heater 10 high-frequency power source (third power source) 11 water cooling tube 12 gas inlet port 13 gas exhaust port 14 magnetic field generator 15 magnetic field generator 16 plasma emission lighting window 17 emission monitor processor 18 microwave generation power source (first power source) Source) 19 tuner rod 20 gate electrode 21 oxide film 22 Si substrate 23 interlayer insulating film 24, 25 through hole 26, 27 base electrode

Claims (9)

[Claims] 1. A method of manufacturing a semiconductor integrated circuit device, wherein plasma is generated by an interaction between a microwave and a magnetic field to perform a predetermined plasma treatment on a sample, the sample stage electrode on which the sample is mounted. A magnetic field in the direction perpendicular to the sample base electrode and the counter electrode, and a space between the sample base electrode and the counter electrode. A method of manufacturing a semiconductor integrated circuit device, comprising: transmitting a microwave from a microwave source to generate plasma, and subjecting the sample mounted on the sample stage electrode to a predetermined plasma treatment. 2. The method for manufacturing a semiconductor integrated circuit device according to claim 1, wherein the electric power supplied to the microwave generation source, the sample stage electrode and the counter electrode can be changed.
A method for manufacturing a semiconductor integrated circuit device, which is changed according to a plasma processing type of a sample placed on the sample stage electrode. 3. The method for manufacturing a semiconductor integrated circuit device according to claim 1, wherein at least one of the sample stage electrode and the counter electrode is temperature-adjustable, and the sample mounted on the sample stage electrode or the counter electrode. A method for manufacturing a semiconductor integrated circuit device, comprising controlling the temperature of the device to a predetermined temperature. 4. The method of manufacturing a semiconductor integrated circuit device according to claim 1, wherein a magnetic field can be adjusted from the outside of a decompression container of at least one of the sample stage electrode and the counter electrode, and electrons and ions in the plasma stay there. A method for manufacturing a semiconductor integrated circuit device, comprising controlling a period. 5. A manufacturing apparatus of a semiconductor integrated circuit device for generating a plasma by an interaction between a microwave and a magnetic field to perform a predetermined plasma treatment on a sample, the sample stage electrode on which the sample is mounted. Is arranged in parallel plate shape with respect to the counter electrode that generates a magnetic field in the direction perpendicular to the sample table electrode and the sample table electrode, and the microwave can be transmitted through the microwave input side. Formed of a ceramic material, the microwave is transmitted from the microwave source to the space between the sample table electrode and the counter electrode, plasma is generated, and the sample is placed on the sample table electrode. And a decompression container in which a predetermined plasma treatment is performed. 6. The manufacturing apparatus for a semiconductor integrated circuit device according to claim 5, wherein a first power source capable of changing power for supplying power to the microwave generation source and power supplying power to the sample stage electrode. An apparatus for manufacturing a semiconductor integrated circuit device, comprising: a changeable second power source and a power changeable third power source for supplying power to the counter electrode. 7. The semiconductor integrated circuit device manufacturing apparatus according to claim 6, wherein the plasma is generated by using the first power source as microwave power, and the second power source is RF.
The energy of ions from the plasma incident on the sample as electric power is controlled, the third electric power source is set to ground potential, and gas is introduced into the decompression container to etch the surface of the sample. And a semiconductor integrated circuit device manufacturing apparatus. 8. The semiconductor integrated circuit device manufacturing apparatus according to claim 6, wherein the plasma is generated by using the first power source as microwave power, and the second power source is RF.
The energy of ions from the plasma incident on the sample is controlled as electric power or ground potential, and the electrode material of the counter electrode is sputtered by using the third electric power source as RF electric power, and gas is introduced into the decompression container. An apparatus for manufacturing a semiconductor integrated circuit device, wherein the surface of the sample is subjected to a sputtering process. 9. The manufacturing apparatus of a semiconductor integrated circuit device according to claim 6, wherein the plasma is generated by using the first power source as microwave power, and the second and third plasmas are generated.
To control the energy of the ions from the plasma incident on the sample with the RF power source as RF power or ground potential,
An apparatus for manufacturing a semiconductor integrated circuit device, characterized in that a reaction of particles in the plasma is promoted and a gas is introduced into the decompression container to perform a CVD process on the surface of the sample.