JP3494933B2 - Semiconductor manufacturing apparatus cleaning method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to semiconductor manufacturing such as a CVD apparatus for forming Ru or RuO ₂ as a conductive material film for manufacturing a semiconductor integrated circuit, or an etching apparatus for patterning a formed conductive material film. The present invention relates to a method for cleaning an apparatus, and in particular, to a method for cleaning a semiconductor manufacturing apparatus, which is suitable for easily removing a reaction product of Ru deposited or adhering to at least the inner wall of the reaction vessel of these apparatuses without damaging the inner wall of the reaction vessel and easily. Concerning the training method.

[0002]

2. Description of the Related Art With the high integration of devices, elements having memory cells such as DRAM have become more and more complicated three-dimensional structures in order to secure the electric capacity of capacitors.
For this reason, the number of manufacturing steps increases, the thin film formation / processing margin becomes narrower, which causes an increase in manufacturing cost and a decrease in yield. Therefore, it has been essential to use a material having a higher dielectric constant than the conventional SiON film as the insulating film for increasing the storage capacity of the capacitor and to simplify the structure.

At present, a multi-component oxide such as BaSrTiO ₃ is being investigated as a high dielectric constant material of this kind. Since a high temperature process of about 600 ° C. in an oxygen atmosphere is used when depositing this high dielectric constant material, the conventional Si cannot be used as the material of the capacitor lower electrode constituting the capacitor, and the material is not easily oxidized. Alternatively, it is necessary to select a material having conductivity even when it is oxidized.

As an electrode material satisfying this condition, Ru,
There is RuO ₂ . As a method of forming these electrode materials, a CVD method that can provide a thin film with high purity and excellent crystallinity, which has good throwing power of the thin film to the substrate with respect to physical vapor deposition
The (chemical vapor deposition) method is considered to be suitable.

As a method for forming a Ru or RuO ₂ thin film, for example, JP-A-6-283438 and JP-A-9-
As described in Japanese Patent No. 246214, a method of forming a film by MO-CVD using a specific organic source gas has been studied.

[0006] In general, a CVD apparatus has a reactor (reaction vessel) for carrying out a film forming reaction, a gas supplier for supplying a raw material gas to the reactor, a gas supply pipe connecting the gas supplier and the reactor, and a reaction gas exhausted from the reactor. And an exhaust pipe connecting the reactor and the exhaust device.

When the film forming reaction is repeated by the CVD apparatus, by-products of the film forming reaction are deposited or adhered on the inner wall of the reactor, the inner wall of the exhaust pipe and the like. Conventionally, as a method for removing the by-products, a CVD apparatus is disassembled, the by-products are removed by etching with a chemical solution containing various acids as main components, and cleaning and drying are performed to assemble and clean up. Therefore, there is a problem that these reduce the operating rate of the device.

Therefore, as for a CVD apparatus for depositing a conventional material such as W, Si, Si ₃ N _4, etc.
As described in JP-A-92385, JP-A-4-155827, JP-A-4-181734, and JP-A-7-78808, halogen-based gas such as ClF ₃ and NF ₃ is heated or plasma is used. An apparatus cleaning method for removing a film-forming reaction by-product deposited or attached on the inner wall of a reaction vessel and the inner wall of a pipe without disassembling the apparatus by reacting with a reaction by-product to generate a substance having a high vapor pressure and exhausting it. Was considered. However, with respect to the CVD apparatus of Ru or RuO ₂ which is a new electrode material, the current situation is that no study has been made on the cleaning method.

On the other hand, regarding the etching method of Ru or RuO ₂ , it is reported that it can be processed by O ₂ / Cl ₂ plasma as described in, for example, Japanese Patent Application Laid-Open No. 8-78396. It has also been reported that etching can be similarly performed using ozone gas. But CVD
A problem similar to that of the apparatus is that reaction by-products are deposited or adhered on the inner wall of the reactor when the etching reaction of the etching apparatus is repeated.

Conventionally, regarding a plasma reaction vessel for producing an organic residue, a method of removing a carbon-based polymer in the plasma reaction vessel by using O ₃ plasma as described in, for example, JP-A-6-53193 has been studied. Has been
The etching method for Ru or RuO ₂ which is a new inorganic material has not been examined yet for the cleaning method.

[0011]

Therefore, an object of the present invention is to eliminate the above-mentioned conventional problems.
Or CVD for forming or etching RuO ₂
It is an object of the present invention to provide an improved cleaning method for a semiconductor manufacturing apparatus capable of removing a reaction by-product containing Ru deposited or adhered to the inner wall of a reaction vessel of the apparatus or the etching apparatus without damaging it. By this,
It is intended to improve the operation rate of the apparatus and prevent the production yield from being lowered due to the generation of particles.

Another object of the present invention is to provide a cleaning method which improves the throughput of the apparatus by performing cleaning in a short time under the condition that high speed cleaning is possible.

A further object of the present invention is to provide a Ru or RuO ₂ -CVD apparatus and a method for cleaning an etching apparatus which does not cause corrosion of the apparatus.

[0014]

Means for Solving the Problems The above-mentioned object is to clean a CVD apparatus by which Ru or RuO ₂ is deposited on a substrate, or by etching the deposited Ru or RuO ₂ to form a pattern. What is claimed is: 1. A method for cleaning a semiconductor manufacturing apparatus including a cleaning method for an apparatus, wherein the reaction product containing Ru, which is deposited or adhered to at least an inner wall of a reaction container of any one of the apparatuses, is removed. O ₃ , halogenated oxygen,
The present invention is achieved by a cleaning method of a semiconductor manufacturing apparatus, which comprises a cleaning step of contacting at least one oxidizing gas selected from the group of N ₂ O and O atoms at 25 to 250 ° C., reacting and removing the oxidizing gas. .

When removing the reaction product containing Ru, the treatment temperature has a great influence on the removal rate. 25 ° C
If it is lower or higher than 250 ° C., the removal rate (etching rate) is remarkably reduced, which is not preferable. If the treatment temperature is 25 to 250 ° C., an etching rate of at least 5 nm / min can be obtained under an O ₃ concentration of 5%.

Further, the more preferable processing temperature 7 of the present invention
At 0 to 200 ° C., an etching rate of at least 50 nm / min is more preferable.
An etching rate of about 0 nm / min is obtained, and at least one gas selected from the group consisting of fluorine, chlorine, bromine, chlorine fluoride, hydrogen fluoride, hydrogen chloride and hydrogen bromide is added to the oxidizing gas. This preferably contributes to the improvement of the etching rate and accelerates the reaction. The addition amount is, for example, 20% or less with respect to the oxidizing gas, 5 to
About 15% is preferable.

The conditions required for the oxidizing gas easily react with the reaction product containing Ru deposited or adhered to the inner wall of the reaction container, and the new reaction product generated thereby is easily discharged to the outside of the reaction container. In the present invention, at least one selected from the group consisting of O ₃ , oxygen halide, N ₂ O, and O atom is selected to satisfy this condition.

Examples of the halogenated oxygen include at least one of oxygen fluoride, chlorine oxide, bromine oxide and iodine oxide. The O atom may be, for example, O ₂ or N ₂ before the reaction container to be cleaned or in the reaction container.
The oxygen atom-containing gas such as O is excited by ultraviolet rays or plasma to generate O atoms.

Further, in consideration of practical processing efficiency, it is preferable that the cleaning step of the present invention is carried out in an atmosphere having a concentration of 5% or more for O ₃ , for example.

Ru has a melting point of about 2450 ° C. and a boiling point of about 3700.
The vapor pressure is low, and the vapor pressure of RuO ₂ is also low. On the other hand, RuO ₄ has a high vapor pressure of 25.4 ° C. and a boiling point of 40 ° C. Therefore, Ru or RuO ₂ -CV
Ru, Ru adhered in the D device or the etching device
If the O ₂ film is converted to RuO ₄ by a chemical reaction, the device can be cleaned because it is easily evaporated and exhausted.

The reaction mechanism of Ru or RuO ₂ and O ₂ , O atom, and O ₃ will be specifically described below as an example. Ru or RuO ₂
And given the reaction of O _2, the following equations (1), (2)
Becomes

[0022]

Embedded image Ru (solid) + 2O ₂ → RuO ₄ ↑ (gas) (1)

[0023]

Embedded image RuO ₂ (solid) + O ₂ → RuO ₄ ↑ (gas) (2) Considering Gibbs free energy change (ΔG) in the standard state of each reaction, ΔG is −140 kJ in the equation (1).
/ Mol, ΔG is 101.77 kJ / mo in the formula (2).
It becomes l. Therefore, in the equilibrium state, the reaction in which Ru becomes RuO ₄ proceeds, but the reaction in which RuO ₂ becomes RuO ₄ hardly progresses.

On the other hand, in the reaction of O, the following equations (3) and (4)
Becomes

[0025]

Embedded image Ru (solid) + 4O → RuO ₄ ↑ (gas) (3)

[0026]

Embedded image RuO ₂ (solid) + 2O → RuO ₄ ↑ (gas) (4) The Gibbs free energy change (ΔG) in the standard state of each reaction is −1067 kJ / mol in the formula (3), and the formula (4) ) Is -361.79 kJ / mol. Therefore, Ru is more likely to form RuO ₄ when it reacts with the O atom of the formula (3) than O ₂ of the formula (1), and in the case of RuO ₂ , the formula (2) is more preferable than the O _{2 of the} formula (2). RuO ₄ can be easily produced by reacting with the O atom of 4).

Further, in the reaction of O ₃ , the following formula (5)
It becomes (6).

[0028]

Embedded image Ru (solid) + 4 / 3O ₃ → RuO ₄ ↑ (gas) (5)

[0029]

Embedded image RuO ₂ (solid) + 2 / 3O ₃ → RuO ₄ ↑ (gas) (6) The Gibbs free energy change (ΔG) in the standard state of each reaction is −357.3 kJ / in the formula (5). mol,
In the formula (6), it is −6.9 kJ / mol. Therefore, although it is more difficult to react than the O atom in the formulas (3) and (4), RuO ₄
Is generated. Further, since O ₃ is easily decomposed into O ₂ and O atom, it is considered that a reaction by O atom also occurs.

From the above, Ru or RuO ₂ to Ru
It will be understood that it is effective to react with an O atom or O ₃ to generate O ₄ .

Although the reaction mechanism between the halogenated oxygen and the reaction product containing Ru deposited or attached to the inner wall of the reaction vessel is not particularly described here, when the halogenated oxygen contacts the inner wall of the reaction vessel, Since the halogenated oxygen decomposes to generate an oxygen (O) atom, the above-described O
You can think in the same way as in the case of atoms.

[0032] The present invention, the reactor inner wall of the CVD device or the etching device, the exhaust pipe inner wall, in order to periodically remove the reaction products deposited or adhere to parts, oxidation such as O atoms and O ₃ for the cleaning By supplying the gas into the apparatus and generating RuO ₄ having a high vapor pressure, it is possible to improve the operation rate of the apparatus and prevent the production yield from decreasing due to the generation of particles.

Furthermore, in the reaction using the above-mentioned oxidizing gas of the present invention, the reaction is carried out at 25 to 250 ° C., and further the reaction is carried out at an O ₃ concentration of 5% or more, whereby cleaning is performed in a short time and the throughput is improved. It is possible to

Further, the above-mentioned oxidizing gas of the present invention makes it possible to perform cleaning without causing corrosion because it forms only a thin oxide film having a low vapor pressure on the metal surface of the apparatus.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION The outline of an embodiment of the present invention will be described with reference to the drawings. Figure 1 shows a CVD method for forming RuO ₂
FIG. 3 is a schematic cross-sectional view of an apparatus, in which the wafer 12 is
A RuO ₂ thin film was formed on the above by CVD. For cleaning the inside of the apparatus after the film formation, the O ₃ gas is ejected from the O ₃ supplier 20s into the apparatus (chamber 11) through the gas shower head 14, and the conductance valve 21 is used to discharge the same amount of gas as in the film formation. Was adjusted.

FIG. 3 is a schematic cross-sectional view of a Ru plasma etching apparatus. A circuit pattern was formed on a Ru thin film formed on a wafer 12 using this apparatus according to a known pattern forming method. For cleaning the inside of the apparatus after the pattern formation by etching, the valve 40v is opened from the O ₃ supplier 40s, O ₃ gas is ejected into the apparatus (bell jar 31) through the gas supply pipe 36, and the conductance valve 41 is used to perform the same cleaning. The exhaust volume was adjusted to.

In this example, the oxidizing gas is O ₃ , and the treatment temperature is 25 to 250 ° C., preferably 70 to 20.
By performing the treatment at 0 ° C. and at the preferable O ₃ concentration of 5% or more, the processing rate (etching rate) is increased, and the throughput can be improved.

Hereinafter, a specific cleaning method for the semiconductor manufacturing apparatus of the present invention will be described with reference to examples.

[0039]

EXAMPLES Example 1 A single wafer processing type CVD apparatus for forming a Ru film, which is a first example of the present invention, will be described with reference to FIG. (1) Apparatus configuration In this CVD apparatus, the reactor part that performs the film formation reaction is SUS
Manufacturing chamber 11, wafer 12, ceramic heater 13 for heating the wafer, and SUS gas shower head 14 for uniformly supplying reaction gas onto the wafer.
Consists of. The pipe 15 for supplying / exhausting the film forming raw material gas and the cleaning gas and the chamber 11 are heated by the heater 16 in order to prevent the reaction products from being adsorbed.

In the chamber 11, Ru (EtCp) ₂ serving as a film forming raw material gas is supplied via a gas supply pipe 15a and valves 17v, 18v, 19v, 20v [EtC
p is an abbreviation for ethylcyclopentadienyl (C ₂ H ₅ C ₅ H ₄ )] and is a gas supply 17 s and an O ₂ supply 1
8s, N ₂ supply device 19s, and O ₃ supply device 20s which is a cleaning gas supply device are connected.

Further, the chamber 1 is connected via the exhaust pipe 15b.
1 Conductance valve for controlling internal pressure 2
1 and the exhaust device 22 are connected.

This apparatus is a cold wall type apparatus for heating the wafer to a temperature of about 200 ° C. to 750 ° C. by a heater 13 on which the wafer 12 is placed to form a film. However, since the vapor pressure of the film-forming source gas is low, the chamber wall and piping are also heated by the heater 16 to about 150 ° C. so that the source gas is not condensed on the inner wall of the apparatus. Therefore, parts other than the wafer also become high in temperature, and an unnecessary reaction byproduct containing Ru is generated due to the decomposition reaction of the raw material gas,
A large amount of these adheres to the inner wall of the chamber and the like.

Further, in order to make the temperature distribution of the wafer uniform, the size of the heater is made larger than the size of the wafer, and the amount of heat input to the peripheral portion of the wafer where heat escape is large is increased. Therefore, Ru is also formed on the periphery of the heater 13. During the repeated film formation, these adhered substances and unnecessary film formation become foreign substances due to peeling and winding due to gas flow, causing defects such as short circuit and disconnection.

On the other hand, O ₃ reacts with Ru by heat at room temperature to produce RuO ₄ having a low vapor pressure. O ₃ also reacts with the source gas containing C to produce RuO ₄ , CO ₂ and H ₂ O.

From the above, O ₃
It should be possible to remove it simply by flowing gas. Therefore, the following method was attempted to improve the operating rate of the CVD apparatus and reduce foreign matter by O ₃ cleaning.

(2) Preliminary examination of cleaning with O ₃ Before performing cleaning with the above apparatus, in order to obtain a guideline for determining the cleaning conditions, the temperature dependence and the pressure dependence of the etching reaction of Ru with O ₃ I checked. The experimental temperature range was 20 ° C to 400 ° C, the pressure range was 10 to 200 Torr in total pressure, and the O ₃ concentration was 1% to 30%.

The experiment was conducted by using the above CVD apparatus, and the Ru film sample which is a specific etching product was the wafer formed by the above CVD apparatus. The Ru film sample was exposed to O ₃ gas in the CVD chamber, and the change in film thickness before and after was calculated from the peak intensity of the fluorescent X-ray.

FIG. 2 shows the temperature dependence of the etching rate. The etching rate reaches a maximum at around 150 ° C and is 1
The rate was lower in each of the lower temperature part and the higher temperature part than 50 ° C. From FIG. 2, if the temperature is 25 ° C. to 250 ° C., 5n
It was found that Ru can be etched by O ₃ at a rate of 50 nm / min or more at m / min or more, and more preferably 70 to 200 ° C. When the temperature dependence was measured, the total pressure was 100 Torr and the O ₃ concentration was 5%.
And

Next, FIG. 3 shows the pressure dependence of the etching rate. The pressure rises as the pressure rises up to a total pressure of around 100 Torr, but the etching rate hardly changes above 100 Torr. The temperature at which the pressure dependence is measured has a maximum rate of 1
The temperature was 50 ° C. and the O ₃ concentration was 5%.

FIG. 4 shows the O ₃ concentration dependence of the etching rate. The O ₃ concentration rises as the concentration increases up to around 20%, but at 20% or more, the etching rate shows almost no change and is saturated. The temperature at the time of measuring the concentration dependence was 150 ° C. at which the rate has a maximum value, and the pressure was 100 Torr of the total pressure.

The cleaning time must consider the throughput of the apparatus. If the throughput per unit (2 chambers) is 300 sheets / day, the throughput per chamber is 150 sheets / day, and 1 lot (25
Must be processed within 4 hours. Excluding the time required for film formation, the cleaning including the precoat in the chamber needs to be completed within about 60 minutes.

The required etching rate depends on the film thickness of Ru to be formed, and if the minimum required etching rate is set to 50 nm / min or more, in order to obtain this rate, the cleaning temperature is determined from FIGS. 70 ℃ ~ 2
Must be 00 ° C. Further, it is desirable that the O ₃ concentration be 5% or more. Below, based on the preliminary examination results,
The results of film formation and cleaning are shown.

(3) Ru Film Forming Method First, the following was performed as a film forming operation. The wafer 12 is placed on the heater 13 while the chamber is evacuated, the heater is heated to 320 ° C., and the wafer is waited until it reaches a thermal equilibrium state. At this time, the temperature of the chamber wall and piping is 150 ° C. After that, the valves 17v and 19v were opened, and Ru (EtCp) ₂ and N ₂ gases were flowed to each other to reach 0.
A film having a thickness of 1 μm was formed. At this time, the exhaust amount was controlled by the conductance valve 21 so that the desired pressure was obtained.

(4) Cleaning Method Using O ₃ After the film formation, the wafer 12 was pulled out and the chamber was evacuated. Usually, foreign matter occurs frequently when the cumulative film thickness reaches 3 μm or more. For this reason, O ₃ cleaning was performed in the following procedure every time 25 LOT wafers were formed.

Preliminary examination of O ₃ cleaning has revealed that the etching rate is very low in a portion where the temperature is 200 ° C. or higher, resulting in a decrease in throughput. R
The film formation temperature of the u film is 300 ° C., and if cleaning is performed at the same heater temperature as that during film formation, it becomes difficult to remove the portion with the most adhesion / deposition by cleaning. Therefore, the heater temperature is set to 150 before cleaning.
It was lowered to ℃.

The time required for raising and lowering the heater temperature is 30 minutes, and if the entire cleaning is performed within 60 minutes, the etching rate is required to be about 100 nm / min or more. Therefore, the O ₃ concentration is set to 10%. The pipe temperature during film formation is 150, which has a high etching rate.
Since the temperature was ° C, cleaning was performed at the same temperature as that during film formation.

[0057] opening the valve 20v, supplying O ₃ feeder 20s than the O ₃ gas, similarly to the deposition was adjusted exhaust volume by a conductance valve. The end point of cleaning is
It was confirmed by attaching a QMS sampling port to the exhaust pipe and measuring the time-dependent change in the ionic strength of the reaction product gas generated during cleaning as shown in FIG.

Specifically, the end point was the point where the ionic strength of RuO ₄ decreased and the change decreased. Since the end point was reached after 10 minutes of gas cleaning, the O ₃ supply was stopped in 12 minutes including some overetching.

Further, a mass spectrometer [QMS: Q uadrupole
CO ₂ was also observed in the measurement of approximately] of M ass S pectrometry. It is considered that this was generated because C contained in the source gas remained and the residual C reacted with O ₃ . Therefore, it is understood that the residue of the raw material gas which has not been completely thermally decomposed can be removed by the cleaning with O ₃ gas.

This series of working steps of film formation and cleaning were repeated for 20 LOTs (25 wafers / 1 LOT), and the transition of the number of foreign matters during that period was measured. The result is shown in Figure 6.
Shown in. It can be seen from FIG. 6 that the number of foreign particles increases as the film formation is repeated within 1 LOT. However,
It can be seen that the foreign matter can be reduced and the generation of the foreign matter can be suppressed in the long term by performing the O ₃ cleaning.

Further, since the inside of the chamber is cleaned every 1 LOT, the fluctuation of the Ru film forming rate was small. Furthermore, as a result of visually observing the surface of the metal part of the apparatus after 20 times of O ₃ gas cleaning, no corrosion or the like was observed, which shows that cleaning without causing damage to the apparatus is possible.

According to this embodiment, foreign matters can be reduced by O ₃ gas cleaning, and the yield can be improved.

Further, according to this embodiment, it is possible to perform cleaning in a short time by optimizing the cleaning conditions, and it is possible to improve the operation rate of the apparatus. Further, since the metal parts are not corroded, the device can be stably operated for a long period of time.

In this embodiment, O is used as the cleaning gas.
₃ was used, but O ₂ and N before or in the chamber were used.
The same effect can be obtained by using, as the cleaning gas, ₂ O excited by ultraviolet rays or plasma to generate O atoms.

In this example, R was used as the film forming source gas.
u (EtCp) ₂ and is used, Ru (DPM) ₃ [However, DPM is D i p ivaloyl m ethanato (C 11 H 19 O 2) abbreviation] Even when the deposition of the Ru or RuO ₂ with The same effect can be obtained by this cleaning method.

<Embodiment 2> Next, a Ru etching apparatus according to a second embodiment of the present invention will be described with reference to FIG. That is, a circuit pattern is formed by plasma etching with a resist mask provided on the Ru film previously formed on the wafer 12 using this apparatus.

(1) Apparatus Configuration The reactor section for carrying out the etching reaction comprises a bell jar 31 made of quartz, a flange 32 made of SUS, a wafer 12, and a wafer setting electrode 33. The wafer installation electrode 33 includes an electrostatic attraction mechanism and a wafer temperature control mechanism.

Further, a solenoid coil 34 and a 2.45 GHz microwave oscillator 35 are used to perform plasma discharge.
And are provided. A gas supply pipe 36 is provided on the flange 32.
And an O ₂ supplier 37s and a Cl ₂ supplier 3 which are etching gases through the valves 37v, 38v, 39v and 40v.
8 s, N ₂ supplier 39 s, O ₃ which is a cleaning gas
The supply device 40s is connected.

Further, a conductance valve 41 for controlling the pressure inside the chamber and an exhaust device 42 are connected to the flange via an exhaust pipe.

When etching is repeatedly performed using the above etching apparatus, a by-product is generated by the reaction between the film to be etched or the resist film and the etching gas, and the by-product is deposited / deposited in the chamber. These become foreign matters due to peeling and rolling up due to gas. Therefore, an attempt was made to reduce foreign matters and improve the operating rate of the etching apparatus by O ₃ cleaning.

(2) Etching of Ru film (pattern formation) First, the following was performed as an etching operation. The wafer 12 having the Ru film patterned with the resist is placed on the electrode 33 while the chamber is evacuated, and the temperature of the wafer is adjusted to 20 ° C. After that, valves 37v, 38
Etching was performed by opening v and 39v, flowing O ₂ , Cl ₂ , and N ₂ gas and simultaneously generating plasma. At this time, the discharge amount was controlled by the conductance valve 41 so that the desired pressure was obtained. After etching, pull out the wafer 12,
The chamber was evacuated.

Usually, when 2 LOT is etched, many foreign substances are generated. For this reason, O ₃ cleaning was performed in the following procedure every time 50 wafers of 2 LOT were etched.

[0073] (3) O ₃ by the cleaning method chestnut - during training is the same city as during deposition the temperature of the wafer holding electrode 33, opens the valve 40v, supplying the O ₃ gas from O ₃ feeder 40 s, the conductance valve The exhaust amount was adjusted by 42. This gas cleaning was carried out for 15 minutes. This etching and cleaning process is performed in 4 steps.
This was repeated for 0 LOT, and the transition of the number of foreign matters during that period was measured.

The results are shown in FIG. It can be seen from FIG. 8 that the number of foreign matters can be maintained at a low level by performing O ₃ gas cleaning. Further, the O ₃ gas cleaning has a high cleaning effect because it can clean all the parts to which the gas can flow, except the part that creates plasma. Furthermore, as a result of visually observing the surface of the metal part of the apparatus after 20 times of O ₃ gas cleaning, no corrosion or the like was observed, and therefore cleaning can be performed without causing damage to the apparatus.

According to this embodiment, foreign matter can be reduced by O ₃ gas cleaning, and the yield can be improved. Further, according to this embodiment, since cleaning can be performed in a short time, it is possible to improve the operation rate of the apparatus. Further, since the metal parts are not corroded, the device can be stably operated for a long period of time.

In this embodiment, O _{3 is} used as the cleaning gas.
However, the same effect can be obtained by cleaning with O atoms generated by being excited by O ₂ or N ₂ O plasma in the chamber.

Example 3 Instead of the O ₃ gas of Examples 1 and 2, at least one oxygen halide of oxygen fluoride, chlorine oxide, bromine oxide and iodine oxide was used as an oxidizing gas. Oxygen halide is supplied from the O ₃ supplier 20s, which is the cleaning gas supplier of FIG. 1 (Example 1),
Then, as the cleaning gas O of FIG. 7 (Example 2),
Oxygen halide was also supplied from each of the ₃ supply devices 40s, and the inside of the apparatus was cleaned in the same manner as in Examples 1 and 2.

In any case, the concentration of oxygen halide is 5
-10%, the pressure is 100 Torr (13.3 kP
a). As a result, the same effect as in the cases of Examples 1 and 2 was obtained.

<Embodiment 4> Further, the oxidizing gas of the above-mentioned Embodiments 1 to 3 is added with fluorine, chlorine, bromine, chlorine fluoride,
When 5 to 15% of at least one gas selected from the group of hydrogen fluoride, hydrogen chloride and hydrogen bromide is added to the oxidizing gas, the etching rate is improved by several% as compared with the case where it is not added, and the gas is further shortened. Cleaning can be done in time, improving the operating rate.

[0080]

As described above in detail, according to the present invention, the intended purpose can be achieved. That is, it is possible to improve the operating rate of the Ru or RuO ₂ -CVD apparatus and the etching apparatus, and prevent the production yield from decreasing due to the generation of foreign matter.

Further, Ru or RuO ₂ -C can be obtained in a short time.
The VD device and the etching device can be cleaned. Furthermore, it is possible to perform cleaning without damaging the device.

[Brief description of drawings]

FIG. 1 is a sectional view showing the structure of a CVD apparatus that is a first embodiment of the present invention.

FIG. 2 is a diagram showing temperature dependence of an etching rate which is a third embodiment of the present invention.

FIG. 3 is a diagram showing pressure dependence of an etching rate which is a third embodiment of the present invention.

FIG. 4 is a diagram showing O ₃ concentration dependence of an etching rate which is a third embodiment of the present invention.

FIG. 5 is a diagram showing a reaction analysis result during cleaning by QMS which is a third embodiment of the present invention.

FIG. 6 is a diagram showing a transition of the number of foreign particles in the CVD apparatus according to the first embodiment of the present invention.

FIG. 7 is a cross-sectional view showing the structure of an etching apparatus that is a second embodiment of the present invention.

FIG. 8 is a diagram showing a transition of foreign matter in the etching apparatus according to the second embodiment of the present invention.

[Explanation of symbols]

11 ... SUS chamber 12 ... Wafer 13 ... Ceramic heater 14 ... SUS gas shower head 15a ... Gas supply 15b ... Exhaust pipe 16 ... Pipe heating heater 17v ... Valve 17s ... Ru (DPM) ₃ supplier 18v ... Valve 18s ... O ₂ supply device 19 v ... Valve 19 s ... N ₂ supply device 20 v ... Valve 20 s ... O ₃ supply device 21 ... Conductance valve 22 ... Exhaust device 31 ... Quartz bell jar 32 ... SUS flange 33 ... Wafer setting electrode 34 ... Solenoid coil 35 Microwave oscillator 36 ... Gas supply pipe 37v ... Valve 37s ... O ₂ supplier 38v ... Valve 38s ... Cl ₂ supplier 39v ... Valve 39s ... N ₂ supplier 40v ... Valve 40s ... O ₃ supplier 41 ... Conductance valve 42 … Exhaust system.

Continuation of the front page (56) Reference JP-A-11-236561 (JP, A) JP-A-2000-299289 (JP, A) JP-A-7-50285 (JP, A) JP-A-2000-174002 (JP, A) ) JP 4-225521 (JP, A) JP 5-335256 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 21/31 H01L 21/205 H01L 21 / 3065

Claims (6)

(57) [Claims] 1. A cleaning method of a CVD apparatus for depositing Ru or RuO ₂ on a substrate, or R deposited
What is claimed is: 1. A cleaning method for a semiconductor manufacturing apparatus, including a cleaning method for an etching apparatus for etching u or RuO ₂ to form a pattern, wherein Ru deposited or attached to at least an inner wall of a reaction vessel of any one of the above apparatuses is used. When removing the reaction product containing, at least one oxidizing gas selected from the group consisting of O ₃ , oxygen halide and O atom is contacted with the reaction product at 25 to 250 ° C.
A cleaning method for a semiconductor manufacturing apparatus, which comprises a cleaning step of removing the reaction product in response to the reaction . 2. The cleaning step is performed at 70 to 200.degree.
The cleaning method for a semiconductor manufacturing apparatus according to claim 1, wherein the cleaning method comprises the step of: 3. The cleaning method for a semiconductor manufacturing apparatus according to claim 1, wherein the cleaning step is performed in an atmosphere having an O ₃ concentration of 5% or more. 4. The oxidizing gas used in the cleaning step is added with at least one reaction accelerating gas selected from the group consisting of chlorine, bromine, hydrogen chloride and hydrogen bromide. A method for cleaning a semiconductor manufacturing apparatus according to claim 1. 5. A step of forming a film of Ru or RuO ₂ on a wafer by a CVD apparatus, and a cleaning step of removing a reaction product containing Ru deposited or attached to at least a reaction container of the CVD apparatus after the film formation. A method of manufacturing a semiconductor device, comprising:
A semiconductor comprising a step of removing the reaction product by contacting a reaction product containing u with at least one oxidizing gas selected from the group consisting of O ₃ , oxygen halide and O atom. Device manufacturing method. 6. Ru or RuO formed on a wafer
₂ to form a resist mask and etch the same with a plasma etching device to form a circuit pattern; and Ru that is deposited or adhered in at least the reaction container of the plasma etching device after forming the circuit pattern.
And a cleaning step of removing a reaction product containing O, wherein the cleaning step comprises adding Ru to the reaction product containing O ₃ , a halogenated oxygen and an O atom. A method of manufacturing a semiconductor device, comprising a step of contacting at least one selected oxidizing gas to remove the reaction product.