JP4529261B2 - Removal method, cleaning method and etching method of composite metal oxide film - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a removal method, a cleaning method, and an etching method of a composite metal oxide film that may contain a plurality of types of metals such as barium, strontium, and titanium.
[0002]
[Prior art]
In general, a semiconductor device is manufactured by repeatedly performing a film forming process and a pattern etching process on a semiconductor wafer to manufacture a desired device. Among them, a film forming technique is used to increase the density and integration of semiconductor devices. Along with this, the specifications, that is, the design rules are becoming stricter year by year. For example, a very thin oxide film such as a capacitor insulating film or a gate insulating film in a device is required to be further thinned. At the same time, higher insulation is required.
[0003]
As these insulating films, a silicon oxide film, a silicon nitride film, or the like can be used. Recently, as a material having better insulating characteristics, a metal oxide film, for example, a dielectric constant of about 30 to 50 is used. And a large tantalum oxide film (Ta₂ O_Five In addition, SrTiO having a dielectric constant larger than that of the tantalum oxide film and having a dielectric constant of about 100 is used._Three (Hereinafter also referred to as STO) and Ba whose dielectric constant is about 200 to 300_X Sr_1-X TiO_Three A composite metal oxide film containing a plurality of types of metals such as (hereinafter also referred to as BSTO) has been studied. The BSTO is generally also referred to as BST.
These composite metal oxide films exhibit a higher dielectric constant than the silicon oxide films and tantalum oxide films that are generally used as described above. Therefore, even if device integration is advanced, a minute capacitor is required. It is possible to secure a sufficient capacity even in the area, and since it can exhibit highly reliable insulation even if it is thin, it is particularly promising as a material for capacitor insulating films and will be used frequently in the future. Expected.
[0004]
[Problems to be solved by the invention]
By the way, in a film forming apparatus for depositing various films on the surface of a semiconductor wafer as is well known, unnecessary adhering films adhering to the inner surface of the processing vessel cause particles, and this is regularly performed. Alternatively, a cleaning process for cleaning and removing irregularly is performed. In this case, this cleaning process includes wet cleaning in which the processing container is removed and cleaned with a cleaning liquid such as an acidic liquid, and dry cleaning in which cleaning is performed using a cleaning gas with IN-SITE without removing the processing container. It has been.
[0005]
The establishment of the above-mentioned dry cleaning method is an important issue from the viewpoint of improving the throughput. However, the unnecessary composite metal oxide film as described above is damaged to the quartz glass that is the material of the processing vessel. The current situation is that a dry cleaning method for removal is not well established. Therefore, the applicant of the present application described in the previous application (Japanese Patent Application No. 2000-157004).₂ Gas and ClF_Three A cleaning method has been proposed in which the composite metal oxide film is removed using different gases, but this cleaning method has the disadvantage that the two types of cleaning gases described above must be used.
The present invention has been devised to pay attention to the above problems and to effectively solve them. An object of the present invention is to remove a composite metal oxide film that can remove an unnecessary composite metal oxide film by using one kind of gas without damaging the processing vessel as much as possible, a cleaning method, and an etching method. Is to provide.
[0006]
[Means for Solving the Problems]
  The inventors of the present invention, after filing the previous application (Japanese Patent Application No. 2000-157004), further studied on the cleaning method of the composite metal oxide film. As a result, in order to remove the composite metal oxide film, Well-known ClF₃ When gas is used, knowledge is obtained that the cleaning operation may be performed at a temperature not lower than the activation temperature of the cleaning gas and not higher than the fluorination temperature of the metal contained in the composite metal oxide film. Thus, the present invention has been achieved.
  The invention defined in claim 1A compound containing at least Ba (barium), Sr (strontium), and Ti (titanium).To remove the mixed metal oxide film, ClF is used as a removal gas.₃ The temperature at which the constituent metal oxide film is not fluorinated while using gasFrom 300 ° C to less than 500 ° CThe composite metal oxide film is removed while maintaining the composite metal oxide film.
  Thereby, it becomes possible to remove the composite metal oxide film almost certainly with one kind of removal gas.
  In this case, for example, as defined in claim 2, the pressure at the time of removal is set within a range of 1 to 25 kPa.
[0007]
  The invention defined in claim 3A compound containing at least Ba (barium), Sr (strontium), and Ti (titanium).In the method for cleaning a mixed metal oxide film, ClF is used as a cleaning gas.₃ The temperature at which the constituent metal oxide film is not fluorinated while using gasFrom 300 ° C to less than 500 ° CThe cleaning method is characterized in that the composite metal oxide film is removed while maintaining.
  According to this, it is possible to almost certainly remove an unnecessary composite metal oxide film adhering to the inside of the processing apparatus for forming a film with one kind of cleaning gas.It becomes.
[0009]
  In this case, for example, billingItem 4As described above, the portion to be cleaned by the cleaning gas is an inner wall of a processing vessel that can be evacuated in order to accommodate the target object and form the composite metal oxide film on the surface of the target object. It is.
  Also, for exampleIn claim 5As specified, at the time of cleaning the inside of the processing container, a processing object supporting means for placing the processing object is accommodated in the processing container. According to this, it becomes possible to simultaneously perform the cleaning process on the inner wall of the processing container and the surface of the object support means.
  For example, as defined in claim 6, the pressure during the cleaning is set within a range of 1 to 25 kPa.
Stipulated in claim 7The invention to be applied is an invention in which the cleaning method is applied to an etching method for pattern-etching a film deposited on a substrate such as a semiconductor wafer, that is, formed on a substrate,A compound containing at least Ba (barium), Sr (strontium), and Ti (titanium).In order to etch the mixed metal oxide film, ClF is used as an etching gas.₃ While using gas, the composite metal oxide film is heated at a temperature at which the constituent metal does not fluorinate.From 300 degrees Celsius to less than 500 degrees CelsiusAn etching method for a composite metal oxide film, characterized in that the composite metal oxide film is etched while being maintained.
  According to this, it becomes possible to pattern-etch the composite metal oxide film formed on the substrate into a predetermined shape with one kind of etching gas.
  In this case, for example, as defined in claim 8, the pressure during the etching is set in a range of 1 to 25 kPa.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a method for removing a composite metal oxide film, a cleaning method, and an etching method according to the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a block diagram showing an example of a processing apparatus capable of carrying out the cleaning method according to the present invention. Here, a case where STO or BSTO is formed as a composite metal oxide film and this unnecessary film is removed by cleaning will be described as an example. The cleaning method and the removal method of the present invention are synonymous.
The processing apparatus 2 includes a vertical processing container 8 having a double tube structure made of quartz, which includes an inner cylinder 4 and an outer cylinder 6. The processing space S in the inner cylinder 4 accommodates a wafer boat 10 made of quartz as a processing object support means for holding a processing object, and this wafer boat 10 is used as a processing object. Semiconductor wafers W are held in multiple stages at a predetermined pitch. A cap 12 is provided to open and close the lower portion of the processing container 8, and a rotating shaft 16 is provided through the cap 12 via a magnetic fluid seal 14. A rotary table 18 is provided at the upper end of the rotary shaft 16, a quartz heat insulating cylinder 20 is provided on the table 18, and the wafer boat 10 is placed on the heat insulating cylinder 20. The rotating shaft 16 is attached to an arm 24 of a boat elevator 22 that can be moved up and down, and can be moved up and down integrally with the cap 12, the wafer boat 10 and the like. It can be inserted and removed from below. For example, a stainless steel manifold 26 is joined to the lower end opening of the processing container 8.
[0011]
Further, an exhaust port 28 is provided on the bottom side wall of the outer cylinder 6, and a vacuum exhaust system 34 formed by connecting a vacuum pump 32 to the exhaust path 30 is connected to the exhaust port 28. The inside of the processing container 8 is evacuated.
In addition, a heat insulating layer 36 is provided on the outer periphery of the processing container 8, and a heater 38 is provided as a heating means on the inner side thereof, and the processing container 8 positioned inside the processing container 8 and the wafer W therein. Is heated to a predetermined temperature.
Here, the overall size of the processing vessel 8 is, for example, that the size of the wafer W to be deposited is 8 inches, the number of wafers held in the wafer boat 10 is about 120 (about 100 product wafers, dummy wafers, etc.). 20), the inner cylinder 4 has a diameter of about 260 to 270 mm, the outer cylinder 6 has a diameter of about 275 to 285 mm, and the processing vessel 8 has a height of about 1280 mm.
Further, the manifold 26 is provided with a processing gas supply means 40 for supplying a processing gas for film formation during the process and a cleaning gas supply means 42 for supplying a cleaning gas required for cleaning as needed. It has been.
[0012]
Specifically, first, the processing gas supply means 40 has a processing gas nozzle 44 provided through the manifold 26, and a flow rate controller 46 such as a mass flow controller is provided in the nozzle 44 on the way. A gas supply path 48 is connected. Further, a processing gas on-off valve 50 is interposed in the middle of the upstream and downstream gas supply paths 48 of the flow rate controller 46. The gas supply path 48 is connected to a raw material tank 54 that stores a raw material liquid 52 that forms a film forming gas here as a processing gas. The raw material liquid 52 is heated by a vaporizing heater 56 provided in the raw material tank 54 to be vaporized to generate a film forming gas.
[0013]
As the raw material liquid 52, when STO is deposited as a composite metal oxide film, for example, Sr (DPM) is used as an organometallic material that is solid at normal temperature and pressure.₂ And Ti (t-BuO)₂ (DPM)₂ And THF (tetrahydrofuran: C) as a solvent at a predetermined weight ratio._Four H₈ O) or a raw material liquid dissolved in butyl acetate can be used. In addition, when BSTO is deposited as a composite metal oxide film, Ba (DPM) is used as an organometallic material that is solid at normal temperature and pressure in addition to the raw material liquid.₂ A raw material liquid in which is dissolved in a predetermined weight ratio can be used. Here, DPM represents dipivaloylmethanate, and t-BuO represents tertiary butoxide. When supplying the film forming gas, N is not shown.₂ An inert gas such as a gas can be used as the carrier gas.
In this case, two or three kinds of organometallic materials are used as the raw material liquid in a mixed state, but these may be used separately and independently so that the raw material gas can be supplied individually so that the flow rate can be controlled. .
[0014]
In addition, an oxidizing gas supply path 58 is connected to the gas supply path 48 in the middle, and the oxidizing gas supply path 58 is connected to a flow rate controller 60 such as a mass flow controller and an oxidizing gas on-off valve. 62 is interposed, for example, O₂ It is connected to an oxidizing gas source 64 that stores oxidizing gas such as gas. The oxidizing gas supply nozzle may be provided separately from the processing gas nozzle 44 so that the oxidizing gas can be supplied individually and independently.
Similarly, the cleaning gas supply means 42 has a cleaning gas nozzle 66 provided through the manifold 26. A cleaning gas flow path 68 connected to the nozzle 66 has a ClF as a cleaning gas._Three ClF storing gas_Three In addition to being connected to the gas source 70, a flow rate controller 72 such as a mass flow controller and a cleaning gas on / off valve 74 are interposed in the middle of the gas flow path 68. Although not shown in the drawing, N is not shown when supplying the cleaning gas.₂ An inert gas such as a gas can be used as the carrier gas.
The gases selectively supplied from the nozzles 44 and 66 ascend the processing space S in the inner cylinder 4 and turn back downward at the ceiling, and are in the gap between the inner cylinder 4 and the outer cylinder 6. Will be discharged. In the figure, 76 is a seal member such as an O-ring that seals between the cap 12 and the manifold 26, and 78 is a seal member such as an O-ring that seals between the manifold 26 and the lower end portion of the outer cylinder 6. It is.
[0015]
Next, a film forming method performed using the processing apparatus configured as described above and a cleaning method (removal method) performed subsequently will be described.
First, the film forming method will be described. A large number of unprocessed semiconductor wafers W are held in multiple stages at a predetermined pitch on the wafer boat 10, and the boat elevator 22 is driven up in this state to process the wafer boat 10. It inserts into the container 8 from the lower side, and the inside of the processing container 8 is sealed. The inside of the processing container 8 is preheated in advance. If the wafer W is inserted as described above, the supply voltage to the heater 38 is increased to raise the temperature of the wafer W to a predetermined process temperature, and the processing chamber 8 is evacuated by the vacuum exhaust system 34. .
[0016]
At the same time, oxygen and film forming gas (including organometallic gas) whose flow rate is controlled are introduced into the processing container 8 from the processing gas nozzle 44 of the processing gas supply means 40. Needless to say, no cleaning gas is supplied during the film forming process.
In this way, the film forming gas introduced into the processing container 8 is oxidized while rising in the processing container 8 to deposit a composite metal oxide film made of STO or BSTO on the wafer surface. The film forming process conditions at this time are such that the wafer temperature is in the range of 400 to 500 ° C., for example, and the pressure is about several hundred Pa.
In this way, when the film forming process is performed for a predetermined time, the supply of the processing gas and oxygen is stopped by closing the processing gas on-off valve 50 and the oxidizing gas on-off valve 62 of the processing gas supply means 40. The film processing is finished.
Then, N in a processing container 8 is supplied from a gas supply system (not shown).₂ Gas replacement is performed by supplying gas and the like, pressure recovery is performed, and the boat elevator 22 is lowered to unload the processed semiconductor wafer W from the processing container 8 and carry it out.
[0017]
Next, a cleaning method (removal method) for removing unnecessary complex metal oxide films adhering to the inside of the processing vessel 8 or the wafer boat 10 will be described.
When the wafer boat 10 is also cleaned, the wafer boat 10 that has been emptied by transferring the wafer W from the wafer boat 10 to a carrier or the like (not shown), that is, the wafer boat 10 in which no wafer is placed, is placed on the heat retaining cylinder 20. In a state of being placed, this is loaded into the processing container 8, and the lower end opening of the processing container 8 is hermetically sealed by the cap 12. In this case, the inner wall of the container and the surface of the wafer boat 10 can be cleaned at the same time. Of course, when the wafer boat 10 is not cleaned, it may be removed from the heat insulating cylinder 20.
Then, the temperature of the processing vessel 8 and the inside thereof is maintained at a predetermined temperature by the heater 38, specifically, a temperature at which the constituent metal in the composite metal oxide film is not fluorinated, as will be described later, for example, less than 500 ° C. ClF which is a cleaning gas from the gas supply means 42_Three A gas is flowed to remove each metal from the unnecessary complex metal oxide film. When supplying the cleaning gas, if necessary, N₂ An inert gas such as Ar, He may be used as the carrier gas.
[0018]
Specifically, both cleaning gas on-off valves 74 and 74 provided in the cleaning gas supply path 68 are opened, and ClF which is a cleaning gas is used._Three The cleaning process is performed for a predetermined time by flowing the gas into the processing container 8 while controlling the flow rate. As a result, not only Ti that is relatively easy to remove, but also Ba and Sr, which are difficult to remove by forming a fluoride at a high temperature of 500 ° C. or higher, are also ClF._Three It reacts with the gas and is gasified and removed. This ClF_Three The process conditions of the cleaning process using the gas are below the temperature at which the constituent metal of the composite metal oxide film is not fluorinated, and the cleaning gas is ClF._Three It is in the temperature range above the activation temperature of the gas, specifically in the range of 300 to less than 500 ° C, preferably in the range of 350 to 450 ° C. The pressure is in the range of 0.1 kPa (0.7 Torr) to 54 kPa (415 Torr), preferably in the range of 1 kPa to 25 kPa.
[0019]
As a result, all metals contained in the film, that is, Ba, Sr, Ti (in the case of a BSTO film), Sr and Ti (in the case of an STO film) are removed by one cleaning process. Therefore, the unnecessary composite metal oxide film is almost completely removed. In addition, the quartz processing vessel 8, the wafer boat 10, and the heat insulating cylinder 20 are hardly damaged.
Here, the cleaning gas ClF_Three Since the effects of the gas on the Sr and Ti in the composite metal oxide film and the effects on the quartz structure such as the processing container were examined and evaluated, the evaluation results will be described. Since Ba has been confirmed to exhibit the same chemical behavior as Sr, which is the same alkaline earth metal, during cleaning, the reduced weight of Ba is substantially the same as that of Sr.
Figure 2 shows ClF_Three FIG. 3 is a graph showing the relationship between the cleaning time for gas and the remaining weight after cleaning._Three FIG. 4 is a graph showing the relationship between the cleaning temperature for gas and the remaining weight after cleaning, and FIG. 4 is a graph showing the degree of quartz damage to the cleaning gas. In FIG. 4, the amount of weight reduction after exposing a predetermined weight of sample quartz to the cleaning gas is shown in mg.
[0020]
First, in the graph shown in FIG. 2, the cleaning time is variously changed to clean (etch) the Sr film and the Ti film. In this case, the cleaning temperature is 500 ° C., the pressure is 13.3 kPa (100 Torr), ClF_Three The gas flow rate is 1.8 slm, N₂ The flow rate of the gas (carrier gas) is 3.2 slm. The initial film thickness of each of the Sr film and the Ti film is 300 nm. As can be seen from this graph, the Sr film has a residual weight of almost 100% even when the cleaning time is extended at a temperature of 500 ° C., and the Sr film (the same for the Ba film) is almost removed at this temperature of 500 ° C. It turned out that it was not possible to clean.
[0021]
On the other hand, when the cleaning time of the Ti film was 5 minutes or longer, the remaining weight showed approximately 0%, and it was found that the Ti film can be removed and cleaned at a temperature of 500 ° C. almost completely.
Next, in FIG. 3, the cleaning temperature is changed (400 ° C. and 500 ° C.) to clean (etch) the Sr film and the Ti film. In this case, the cleaning pressure is 13.3 kPa (100 Torr), ClF_Three The gas flow rate is 1.8 slm, N₂ The flow rate of gas (carrier gas) is 3.2 slm, and the cleaning time is 10 minutes. The initial film thickness of each of the Sr film and the Ti film is 300 nm. As is apparent from this graph, the Ti film was removed both when the cleaning temperature was 400 ° C. and at 500 ° C., and the remaining weight showed approximately 0%, and it was found that the cleaning was performed effectively. did.
[0022]
On the other hand, with respect to the Sr film, when the cleaning temperature is 500 ° C., as described above, the remaining weight shows almost 100% and is hardly removed, but when the cleaning temperature is 400 ° C. The residual weight was about 30%, and it was found that the Sr film was considerably removed and sufficiently cleaned. That is, it has been found that if the cleaning temperature is lowered to about 400 ° C., not only the Ti film but also the Sr film (including the Ba film) can be removed and cleaned.
As described above, the reason why the Sr film is removed at a temperature of 400 ° C. but not at a temperature of 500 ° C. is that the Sr atom is fluorinated between 400 ° C. and 500 ° C., for example, SrF which is a fluoride.₂ There is a temperature range that changes to_Three This is probably because some gases cannot be removed. In this case, in order to remove both the Sr film and the Ti film, the cleaning temperature is preferably set to 450 ° C. or less, taking the intermediate point between the two temperatures. In addition, ClF_Three Since the gas activation temperature is approximately 300 ° C., the lower limit of the cleaning temperature is approximately 300 ° C., which is the temperature at which the cleaning gas is activated. Therefore, ClF_Three It turns out that the temperature at the time of cleaning using gas should be set in the range of 300 to less than 500 ° C.
[0023]
Incidentally, when the degree of damage to quartz in the above temperature band is examined, as is apparent from FIG. 4, damage to quartz increases rapidly when the temperature and pressure are increased. When set to 10 mg, within the temperature range of 300 to 500 ° C., not only when the pressure is 0.13 kPa, but also when the pressure is 13 kPa, the amount of decrease is within 10 mg and the durability against quartz is sufficiently high. Turned out to be.
In the above embodiment, the case where the cleaning method of the present invention is performed in the processing apparatus 2 having the double tube structure in which the processing container 8 is composed of the inner cylinder 4 and the outer cylinder 6 has been described as an example. Of course, for example, the method of the present invention can be carried out even in a processing apparatus having a single tube structure.
[0024]
FIG. 5 is a view showing a single pipe structure processing apparatus for carrying out the method of the present invention. Note that the same components as those shown in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.
As shown in FIG. 5, in this processing apparatus, the processing container 8 is made of, for example, one cylindrical quartz glass and has a single tube structure. An exhaust port 80 is formed in the ceiling portion of the processing container 8, and a vacuum exhaust system 34 is connected to the exhaust port 80 by providing a vacuum pump 32 in the exhaust path 30. In the case of the processing container 8, the gas introduced from the nozzles 44 and 66 at the lower part of the processing container 8 rises in the processing container 8, and the exhaust port 80 provided in the ceiling portion of the processing container 8. As a result, it is evacuated out of the container.
Even when the cleaning process is performed using such a processing apparatus, the same effects as described with reference to FIG. 1 are exhibited.
In the above embodiment, the cleaning method (removal method) of the composite metal oxide film has been described. However, the present invention is not limited to this. It can also be applied to etching.
[0025]
FIG. 6 is a process diagram for explaining such a method of etching a composite metal oxide film.
First, as shown in FIG. 6A, a composite metal oxide film 84 made of STO or BSTO is entirely formed on the surface of a substrate 82 such as a semiconductor wafer or an LCD substrate as described above. Such a deposition operation of the film 84 may be performed by, for example, the processing apparatus shown in FIG. A patterned mask 86 is formed on the surface of the composite metal oxide film 84.
As this mask 86, ClF_Three Any material may be used as long as it is highly corrosion resistant to the gas. For example, a silicon oxide film or a photoresist can be used.
[0026]
Next, this substrate 82 is carried into an etching apparatus (not shown), and as shown in FIG._Three The composite metal oxide film 84 exposed on the surface is selectively etched using a gas. The temperature of the substrate 82 at the time of etching is a temperature range at the time of cleaning as described in the previous embodiment, that is, within a range of 300 to less than 500 ° C., for example, 400 ° C.
When the composite metal oxide film is pattern-etched using the mask 86 as described above, the mask 86 (see FIG. 6B) is then completely removed as shown in FIG. 6C. Then, the etching process is finished.
As described above, according to the etching method of the present invention, the composite metal oxide film formed on the substrate is converted into one etching gas (ClF)._Three ) Can be selectively etched.
[0027]
In each of the above embodiments, the case where the BSTO film or the STO film is used as the composite metal oxide film to be subjected to the cleaning process or the etching process has been described as an example. However, the present invention is not limited to this. For example, SBTO film (SrBi₂ Ta₂ O₉ ), SRO membrane (SrRuO_Three ), LSCO membrane (La_1-x Sr_x CoO_Three ) Etc.
Further, here, a batch type processing apparatus capable of processing a plurality of wafers at a time has been described as an example. However, the present invention is not limited to this, and the present invention is applied to a single wafer processing apparatus that processes wafers one by one. Of course you can.
Furthermore, the object to be processed is not limited to a semiconductor wafer, but can be applied to an LCD substrate and a glass substrate.
[0028]
【The invention's effect】
  As described above, according to the method for removing a composite metal oxide film, the cleaning method, and the etching method of the present invention, the following excellent effects can be exhibited.
  Claim1 and the claims that cite itAccording to the present invention, the composite metal oxide film can be removed almost certainly with one kind of removal gas.
  Claim3 and the claims that cite itAccording to the invention, an unnecessary complex metal oxide film adhering to the inside of the processing apparatus for forming a film can be removed almost certainly with one kind of cleaning gas.
  Especially in claim 5According to the invention, the inner wall of the processing container and the surface of the object support means can be cleaned at the same time.
  Claim7 and the claims that cite itAccording to the invention, the composite metal oxide film formed on the substrate can be pattern-etched into a predetermined shape with one kind of etching gas.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an example of a processing apparatus capable of performing a cleaning method according to the present invention.
FIG. 2 ClF_Three It is a graph which shows the relationship between the cleaning time with respect to gas, and the residual weight after cleaning.
FIG. 3 ClF_Three It is a graph which shows the relationship between the cleaning temperature with respect to gas, and the residual weight after cleaning.
FIG. 4 is a diagram showing a degree of quartz damage to a cleaning gas.
FIG. 5 is a view showing a processing apparatus having a single tube structure for carrying out the method of the present invention.
FIG. 6 is a process diagram for explaining a method of etching a composite metal oxide film.
[Explanation of symbols]
2 processing equipment
4 inner cylinder
6 outer cylinder
8 Processing container
10 Object support means (wafer boat)
42 Cleaning gas supply means
66 Cleaning gas nozzle
68 Cleaning gas flow path
70 ClF_Three Gas source
74 Cleaning gas on-off valve
82 substrates
84 Composite metal oxide film
86 Mask
W Semiconductor wafer (object to be processed)

Claims (8)

In order to remove the double focus metal oxide film containing at least Ba and (barium) Sr and (strontium) Ti and (titanium), wherein the composite metal oxide film, the constituent metal while using a ClF ₃ gas as a stripping gas The composite metal oxide film is removed while maintaining the temperature at 300 ° C. to less than 500 ° C., which is a temperature at which no fluorination occurs. The method for removing a composite metal oxide film according to claim 1, wherein the pressure at the time of removal is set within a range of 1 to 25 kPa. In the cleaning method of the double coupling metal oxide film containing at least Ba and (barium) Sr and (strontium) and Ti (titanium), the composite metal oxide film while using a ClF ₃ gas as a cleaning gas, its constituent metal A cleaning method, characterized in that the composite metal oxide film is removed while maintaining a temperature of 300 ° C. to less than 500 ° C., which is a temperature at which no fluorination occurs. The portion to be cleaned by the cleaning gas is an inner wall of a processing vessel that can be evacuated in order to accommodate the object to be processed and form the composite metal oxide film on the surface of the object to be processed. 3. Symbol mounting the cleaning method to.   The cleaning method according to claim 4, wherein when the inside of the processing container is cleaned, a processing object supporting means for placing the processing object is accommodated in the processing container. The cleaning method according to any one of claims 3 to 5, wherein the cleaning pressure is set in a range of 1 to 25 kPa. Formed on the substrate, in order to etch a multi-focus metal oxide film containing at least Ba and (barium) Sr and (strontium) Ti and (titanium), the composite metal oxide while using a ClF ₃ gas as an etching gas A method of etching a composite metal oxide film, characterized in that the composite metal oxide film is etched while maintaining the physical film at a temperature of 300 ° C. to less than 500 ° C., which is a temperature at which the constituent metal does not fluorinate . 8. The method for etching a composite metal oxide film according to claim 7, wherein the pressure during the etching is set in a range of 1 to 25 kPa.

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