JP2010163679A - Film deposition system and film deposition method for oxide thin film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film deposition system for an oxide thin film where, when an oriented metallic substrate is heat-treated in a reducing atmosphere directly before the formation of an oxide thin film, the phenomenon that heat treatment time is made longer than required so as to cause the increase in cost does not occur, and further, the phenomenon that heat treatment temperature is made higher than required so as to cause the reduction in quality does not occur, and to provide a method for depositing an oxide thin film using the system. <P>SOLUTION: In the film deposition system for the oxide thin film, directly behind a reduction heat treatment chamber in which an oxide layer on the surface of a long-length oriented metallic substrate is removed, provided with a film deposition chamber where an oxide thin film is deposited on the surface of the oriented metallic substrate carried from the reduction heat treatment chamber, the space between the reduction heat treatment chamber and the film deposition chamber is provided with an atmosphere shielding part making the mutual atmospheres of the reduction heat treatment chamber and the film deposition chamber into the substantially independent atmospheres, and further, each of the reduction heat treatment chamber and the film deposition chamber is provided with a gas feed mechanism and an exhaust mechanism. The film deposition method uses the system. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an oxide thin film deposition apparatus and a film deposition method, and more particularly to formation of an oxide thin film in which reduction heat treatment and film deposition are performed in an atmosphere independent from each other when an oxide thin film is formed on a long substrate. The present invention relates to a film apparatus and a film forming method.

Since the discovery of high-temperature superconductors, high-temperature superconducting wires have been actively developed for applications in devices such as cables, current limiters, and electromagnets. A typical current high-temperature superconductor is an oxide such as RE ₁ Ba ₂ Cu ₃ O _7-δ (where RE represents a rare earth element). In order to obtain an excellent high-temperature superconducting wire, It is necessary to form a highly oriented thin film for the oxide.

  For this reason, as a long wire substrate, for example, a long alignment metal substrate in which metal atoms are biaxially aligned, such as Ni, is used, and an oxide thin film is epitaxially grown on the alignment metal substrate. An intermediate layer having the same biaxial orientation is formed, and a superconducting layer having the same biaxial orientation as that of the intermediate layer is formed by epitaxially growing a superconducting layer on the intermediate layer.

However, even when such an oriented metal substrate is used, when the surface of the oriented metal substrate is oxidized to form an oxide layer, the biaxial orientation of the oriented metal substrate surface is impaired, and an intermediate layer is formed. Oxide thin films such as CeO ₂ tend to have a unique orientation (uniaxial orientation with the <111> axis oriented perpendicular to the substrate surface), making it difficult to form an epitaxial intermediate layer on an oriented metal substrate Therefore, it becomes difficult to form a superconducting layer having an orientation suitable for superconductivity.

  In order to solve such a problem, for example, in Patent Document 1, the oxide layer on the surface of the oriented metal substrate is removed by performing a heat treatment on the oriented metal substrate in a reducing atmosphere immediately before the formation of the oxide thin film. It has been proposed.

JP 2005-1935 A

  However, in Patent Document 1, an oxide thin film is formed immediately after performing a reduction heat treatment on a long substrate transported in one processing chamber (a room in which treatment is performed), or an upstream reduction heat treatment is performed. A long substrate subjected to reduction heat treatment in the chamber is transferred to the downstream deposition chamber through the opened passage, and an oxide thin film is formed in the chamber.

  At this time, the gas supply mechanism is provided in the reduction heat treatment chamber and the exhaust mechanism is provided in the film formation chamber even when processing is performed in two processing chambers as well as in the case where the processing chamber is one. The reduction heat treatment for removing the oxide layer and the film forming process for forming the oxide thin film on the substrate from which the oxide layer has been removed are performed in an atmosphere having the same composition.

  However, the optimum atmosphere composition differs between the reduction heat treatment and the film formation treatment. That is, in the reduction heat treatment, from the viewpoint of removing oxygen from the oxide layer, a reducing gas in the atmosphere, such as hydrogen, is preferable as the partial pressure is increased. However, in the film forming process, if the partial pressure of the reducing gas is large, it may be combined with oxygen for forming the oxide thin film, which may cause oxygen vacancies in the oxide thin film. Is not preferred.

  Therefore, since the formation of the oxide thin film is prioritized (important) over the removal of the oxide layer on the substrate surface, an atmosphere composition suitable for the formation of the oxide thin film, that is, an atmosphere in which the reducing gas composition is reduced. As compensation for removing the oxide layer, it is conceivable to lengthen the heat treatment time or raise the heat treatment temperature.

  However, in order to lengthen the heat treatment time, it is necessary to lower the substrate transfer speed or lengthen the treatment chamber, which may cause a significant cost increase.

  In addition, when the heat treatment temperature is increased, the oxide layer can be removed in a short time, but on the other hand, the substrate is stretched due to tension, and the surface flatness is deteriorated due to recrystallization of the alignment metal as the substrate. In addition, adverse effects such as deterioration of crystal orientation and the like may occur, leading to deterioration in quality.

  Therefore, in view of the above-described problems, the present invention does not increase the cost by extending the heat treatment time more than necessary when the oriented metal substrate is heat-treated in a reducing atmosphere immediately before the formation of the oxide thin film. It is another object of the present invention to provide a film forming apparatus for an oxide thin film that does not cause deterioration in quality by raising the heat treatment temperature more than necessary, and a method for forming an oxide thin film using such an apparatus. .

  The present invention has been made for the purpose of solving the above problems, and the atmospheres of the respective processing chambers for removing the oxide layer from the substrate surface and forming the oxide film on the substrate surface are made independent of each other. These are controlled so that the atmosphere is suitable for each treatment. The invention of each claim will be described below.

The invention described in claim 1
Oxidation provided with a film forming chamber for forming an oxide thin film on the surface of the oriented metal substrate conveyed from the reducing heat treatment chamber immediately after the reducing heat treatment chamber for removing the oxide layer on the surface of the long oriented metal substrate An apparatus for forming a thin film,
Between the reduction heat treatment chamber and the film formation chamber, an atmosphere blocking unit is provided that makes the atmosphere of the reduction heat treatment chamber and the film formation chamber substantially independent from each other,
Further, the oxide thin film deposition apparatus is characterized in that a gas supply mechanism and an exhaust mechanism are provided in each of the reduction heat treatment chamber and the film deposition chamber.

  According to the present invention, the reduction heat treatment chamber and the film formation chamber are controlled so as to have an optimum atmosphere for each treatment, and the removal of the oxide layer on the substrate and the formation of the oxide thin film are performed in an optimum atmosphere for each. Therefore, an excellent oxide thin film can be formed on a long substrate.

  The atmosphere blocker separates the reduction heat treatment chamber and the film formation chamber, and is provided with a small hole through which the long substrate can pass. Except for the vicinity of this hole, the reduction heat treatment chamber and the film formation chamber are provided. Therefore, the atmospheres in the reduction heat treatment chamber and the film formation chamber can be made substantially independent from each other.

  Each atmosphere in each processing chamber can be set by a gas supply mechanism (for example, a gas supply device) and an exhaust mechanism (for example, an exhaust device) provided in each processing chamber. By controlling the supply and exhaust of the gas, the atmospheres in the reduction heat treatment chamber and the film formation chamber can be independently adjusted to the optimum atmosphere.

  As described above, the atmospheres of the reduction heat treatment chamber and the film formation chamber are substantially independent of each other, and the gas supply mechanism and the exhaust mechanism are provided in each treatment chamber. Therefore, the oxide layer is also removed from the reduction heat treatment chamber. It is possible to set an optimum atmosphere for the reduction heat treatment, and it is not necessary to perform the reduction heat treatment in an atmosphere suitable for the formation of the oxide thin film (an atmosphere in which the composition of the reducing gas is reduced), and the heat treatment time is longer than necessary. It is not necessary to increase the heat treatment temperature or to make the heat treatment temperature higher than necessary. As a result, it is possible to perform reduction heat treatment in a short period of time by preventing the occurrence of various adverse effects due to the treatment at a high temperature, thereby suppressing an increase in cost.

  In the film formation chamber, an optimum atmosphere for forming a good oxide thin film can be set similarly. As a result, in combination with the above-described reduction heat treatment under the optimum atmosphere, an oxide thin film having excellent quality can be formed on the oriented metal substrate from which the oxide layer has been sufficiently removed.

The invention described in claim 2
2. The oxide thin film deposition apparatus according to claim 1, wherein the atmosphere blocking section has an exhaust mechanism.

  In the present invention, since the atmosphere blocking part has the exhaust mechanism, the atmospheres of the reduction heat treatment chamber and the film forming chamber can be made more independent.

The invention according to claim 3
The film formation chamber is composed of a first film formation chamber and a second film formation chamber;
2. The atmosphere blocking portion is provided between the first film forming chamber and the second film forming chamber, and an atmosphere blocking portion is provided to make each atmosphere substantially independent. The oxide thin film deposition apparatus according to Item 2.

  In the invention of this claim, since the film forming chambers are divided into the first film forming chamber and the second film forming chamber which are substantially independent from each other, the atmosphere in each chamber is reduced. By appropriately changing the properties such as the oxidation property or the oxidization property, it becomes possible to respond more finely in the removal of the oxide layer of the substrate and the formation of the oxide thin film, and it is possible to form an oxide thin film with better quality.

The invention according to claim 4
A film forming method for forming an oxide thin film on the surface of a long oriented metal substrate,
In a reduction heat treatment chamber controlled to a predetermined atmosphere, a reduction heat treatment step for removing an oxide layer on the surface of the oriented metal substrate;
The oriented metal substrate from which the oxide layer has been removed is provided immediately after the reduction heat treatment chamber via an atmosphere blocking portion and controlled to a predetermined atmosphere substantially independent of the atmosphere of the reduction heat treatment chamber. A transporting process for transporting to the film forming chamber;
A film forming method for forming an oxide thin film on the surface of the oriented metal substrate conveyed from the reduction heat treatment chamber in the film forming chamber.

  In the invention of this claim, each atmosphere is substantially independent by the atmosphere blocker, and each of the reduction heat treatment and the film formation chamber has a predetermined atmosphere suitable for the reduction heat treatment and film formation. Since the film treatment is performed, an excellent oxide thin film can be formed on the oriented metal substrate from which the oxide layer has been sufficiently removed.

The invention described in claim 5
The film forming step includes
A first film forming step of forming a first oxide thin film on a surface of the oriented metal substrate transported from the reduction heat treatment chamber in a reducing atmosphere in a first film forming chamber;
A transfer step of transferring the oriented metal substrate on which the first oxide thin film has been formed to a second film formation chamber via an atmosphere blocking unit;
The second film formation chamber includes a second film formation step of forming a second oxide thin film on the surface of the first oxide thin film in an oxidizing atmosphere. 4. The method for forming an oxide thin film according to 4.

  The oxide thin film is preferably formed in an oxidizing atmosphere. However, under an oxidizing atmosphere, before the oxide thin film is formed on the substrate surface, the oriented metal substrate from which the oxide layer has been removed by the reduction heat treatment is oxidized again.

  For this reason, in the present invention, the first oxide thin film is previously formed thinly in a reducing atmosphere in the first film forming step. As a result, in the second film forming step, which is an original oxide thin film forming step in which an oxide thin film is formed in an oxidizing atmosphere, the thin first oxide thin film is formed on the substrate. An oxide thin film that does not have oxygen vacancies can be formed as the second oxide thin film without functioning as a barrier that prevents oxidation again and without oxidizing the substrate. Note that the reducing atmosphere in the first film formation step is preferably a weak reducing atmosphere so that the first oxide thin film is not in an oxygen deficient state.

  According to the present invention, when the oriented metal substrate is heat-treated in a reducing atmosphere immediately before the formation of the oxide thin film, the heat treatment time is not prolonged and the cost is not increased, and the heat treatment temperature is increased more than necessary. It is possible to provide a film forming apparatus for an oxide thin film that does not cause a deterioration in quality by increasing the height, and a method for forming an oxide thin film using such an apparatus.

It is a figure which shows the structure of the principal part of the film-forming apparatus of the oxide thin film which concerns on the 1st Embodiment of this invention. It is a figure which shows the structure of the atmosphere interruption | blocking part of the film-forming apparatus of the oxide thin film which concerns on the 2nd Embodiment of this invention. It is a figure which shows the structure of the atmosphere interruption | blocking chamber of the film-forming apparatus of the oxide thin film which concerns on the 3rd Embodiment of this invention. It is a figure which shows the structure of the principal part of the film-forming apparatus of the oxide thin film which concerns on the 4th Embodiment of this invention. It is an X-ray diffraction pattern about the thin film obtained by the Example of this invention. It is an X-ray diffraction pattern about the thin film obtained by the Example of this invention.

  Hereinafter, the present invention will be described based on the best mode. Note that the present invention is not limited to the following embodiments. Various modifications can be made to the following embodiments within the same and equivalent scope as the present invention.

(First embodiment)
In the first embodiment, an atmosphere blocking portion having a small hole for passing a long substrate is provided between the reduction heat treatment chamber and the film forming chamber, thereby preventing the atmosphere gases in both chambers from mixing with each other. This is an example of an oxide thin film deposition apparatus capable of maintaining the atmosphere in both chambers substantially independently of each other and maintaining the optimum atmosphere for each treatment. Hereinafter, the present embodiment will be described with reference to FIG.

  FIG. 1 is a diagram showing a configuration of a main part of an apparatus for forming an oxide thin film on a long substrate according to the present embodiment. In FIG. 1, 10 is a long board | substrate, 21 is a supply roll of the board | substrate 10, 22 is a winding roll. Further, 30 is a reduction heat treatment chamber, 31 is a heater provided in the reduction heat treatment chamber 30, 35 is a gas supply device for supplying a predetermined gas to the reduction heat treatment chamber 30, and 36 is an exhaust device. It is.

  40 is a film forming chamber, 41 is a heater provided in the film forming chamber 40, 45 is a gas supply device for supplying a predetermined gas to the film forming chamber 40, and 46 is an exhaust device. is there. Reference numeral 90 denotes a target (material) for forming an oxide thin film on the substrate 10. Further, an atmosphere blocking wall 50 having a small hole 50a is provided between the reduction heat treatment chamber 30 and the film forming chamber 40 as an atmosphere blocking portion.

  Reference numeral 11 denotes an oxide layer on the surface of the substrate 10 before the reduction heat treatment, and 91 denotes an oxide thin film formed on the surface of the substrate 10.

  In the oxide thin film deposition apparatus according to the present embodiment, an oriented tape-like long substrate 10 made of a Ni-based alloy is unwound from a supply roll 21, and is applied to a reduction heat treatment chamber 30 and an atmosphere blocking wall 50. After being conveyed through the provided small hole 50 a and the film forming chamber 40, the film is wound around the winding roll 22. On the way, the oxide layer 11 on both the upper and lower surfaces is reduced by being exposed to a heated reducing atmosphere in the reduction heat treatment chamber 30, and immediately after that, an oxide thin film 91 is formed on the lower surface of the substrate 10 in the film formation chamber 40. Is done.

  Each of the reduction heat treatment chamber 30 and the film forming chamber 40 is provided with gas supply devices 35 and 45 serving as gas supply mechanisms and exhaust devices 36 and 46 serving as exhaust mechanisms. It is possible to keep the optimum atmosphere independently, that is, the atmosphere in the reduction heat treatment chamber 30 is the optimum atmosphere for reduction, and the atmosphere in the film forming chamber 40 is the optimum atmosphere for film formation.

  The atmosphere of the reduction heat treatment chamber 30 that is optimal for reduction is preferably a strong reducing atmosphere such as a hydrogen atmosphere. By adopting a strong reducing atmosphere, the reducing heat treatment can be performed in a short time without particularly raising the temperature during the reducing heat treatment.

The atmosphere in the film formation chamber 40 that is optimal for film formation is preferably an inert atmosphere such as Ar or Ar + H ₂ or a weak reducing atmosphere. This is because oxygen deficiency may occur in the formed oxide thin film 91 when the atmosphere in the film formation chamber 40 is a strong reducing atmosphere. On the other hand, in order to prevent the occurrence of oxygen deficiency, when the atmosphere of the film formation chamber 40 is an atmosphere containing oxygen such as Ar + oxygen, the substrate 10 subjected to the reduction heat treatment is oxidized when it moves to the film formation chamber 40. There is also a risk that the atmosphere in both chambers mixes in the vicinity of the small holes 50a and reacts to generate water.

Specifically, for example, the reducing heat treatment chamber 30 and the film forming chamber 40 are adjusted by adjusting the gas supply devices 35 and 45 and the exhaust devices 36 and 46 by using an atmospheric gas composed of Ar + H ₂ having the same composition. By increasing the gas pressure in the chamber 30 and increasing the hydrogen partial pressure in the reduction heat treatment chamber 30, the atmosphere in the reduction heat treatment chamber 30 is made an atmosphere suitable for the reduction heat treatment, while the gas pressure in the film formation chamber 40 is lowered. Thus, the atmosphere in the film formation chamber can be changed to an atmosphere suitable for film formation.

  The size of the cross section of the small hole 50a and the thickness of the atmosphere blocking wall 50 are appropriately set so that the substrate 10 can pass through without difficulty and the atmospheric gas in the reduction heat treatment chamber 30 and the film formation chamber 40 is not mixed as much as possible. ing.

  In this embodiment, since the film formation chamber 40 is provided immediately after the reduction heat treatment chamber 30, film formation can be performed immediately after performing the reduction heat treatment, and the substrate is oxidized before film formation. Can be suppressed.

  In general, the time during which the substrate 10 is exposed to the atmosphere in the reduction heat treatment chamber 30 is about 5 to 20 minutes, and as the temperature, the reduction heat treatment chamber 30 (and the temperature of the substrate in the reduction heat treatment chamber) is 850 to 850. The film formation chamber 40 (and the temperature of the substrate in the film formation chamber) is about 600 to 870 ° C.

  The substrate 10 is not particularly limited as long as it is an oriented metal substrate used for a thin film superconducting wire substrate, for example, a long Ni or Ni—W alloy (Ni 95 mol) having a width of about 10 mm and a thickness of about 100 μm. %, Fe5 mol%) and the like.

  In addition, the atmosphere blocking wall 50 may be variable or replaceable even if the cross-sectional size of the small hole 50a is variable in accordance with the cross-sectional shape and dimensions of the long substrate 10 that passes therethrough.

(Second Embodiment)
The second embodiment is an example of a film forming apparatus that increases the thickness of the atmosphere blocking wall 50 of the film forming apparatus according to the first embodiment. Hereinafter, the present embodiment will be described with reference to FIG.

  FIG. 2 is a diagram illustrating a configuration of an atmosphere blocking unit of the apparatus for forming an oxide thin film on a long substrate according to the present embodiment. In the case of the film forming apparatus according to the present embodiment, by increasing the thickness of the atmosphere blocking wall 50, the length of the small hole 50a is increased, and the atmospheric gas in the reduction heat treatment chamber 30 and the film forming chamber 40 is less likely to be mixed. As a result, the atmospheres in the two rooms can be made sufficiently independent to maintain a more optimal atmosphere.

(Third embodiment)
The third embodiment is an example of a film forming apparatus in which an atmosphere blocking chamber provided with an exhaust mechanism is provided as an atmosphere blocking section between the reduction heat treatment chamber and the film forming chamber. Hereinafter, the present embodiment will be described with reference to FIG.

  FIG. 3 is a diagram showing the configuration of the atmosphere blocking chamber of the film forming apparatus according to the present embodiment. In FIG. 3, 52 is an atmosphere blocking chamber provided between the reduction heat treatment chamber 30 and the film forming chamber 40, and 53 is an atmosphere blocking wall provided between the reduction heat treatment chamber 30 and the atmosphere blocking chamber 52. , 54 are atmosphere blocking walls provided between the film forming chamber 40 and the atmosphere blocking chamber 52, and 53a, 54a are small holes provided in the atmosphere blocking walls 53, 54, respectively. Reference numeral 56 denotes an exhaust device provided in the atmosphere blocking chamber 52.

  In the present embodiment, not only two atmosphere blocking walls 53 and 54 are provided between the reduction heat treatment chamber 30 and the film forming chamber 40, but also an atmosphere blocking chamber 52 is provided, and the exhaust device 56 provides a small hole 53 a. , 54a, the atmospheric gas that has entered the atmosphere blocking chamber 52 is excluded, so that the atmospheric gases in the atmospheres of the reduction heat treatment chamber 30 and the film forming chamber 40 can be almost completely prevented from being mixed.

(Fourth embodiment)
The fourth embodiment is an example of an oxide thin film deposition apparatus that performs a film deposition process in two stages. Hereinafter, the present embodiment will be described with reference to FIG.

  FIG. 4 is a diagram showing a configuration of a main part of an apparatus for forming an oxide thin film on a long substrate according to the present embodiment. In FIG. 4, 60 is a first film forming chamber, 61 is a heater provided in the first film forming chamber 60, and 62 is a target. Reference numeral 65 denotes a gas supply device for supplying a predetermined gas to the first film formation chamber 60, and 66 denotes an exhaust device.

  Reference numeral 70 denotes a second film formation chamber, reference numeral 71 denotes a heater provided in the second film formation chamber 70, and reference numeral 72 denotes a target. 75 is a gas supply device for supplying a predetermined gas to the second film forming chamber 70, and 76 is an exhaust device.

  In addition, an atmosphere blocking wall 51 having a small hole is provided between the first film forming chamber 60 and the second film forming chamber 70. Reference numeral 92 denotes a first oxide thin film formed on the surface of the substrate 10 in the first film formation chamber 60, and 93 denotes a second oxide thin film formed in the second film formation chamber 70. . In addition, about the code | symbol same as the code | symbol shown in FIG. 1, since description overlaps, it abbreviate | omits.

  In the oxide thin film deposition apparatus according to the present embodiment, the long substrate 10 is exposed to the heated reducing atmosphere in the reduction heat treatment chamber 30, whereby the oxide layers 11 on both the upper and lower surfaces are reduced. Thereafter, the film is transferred to the first film forming chamber 60 through the atmosphere blocking wall 50.

  The first film formation chamber 60 is set in a reducing atmosphere by a gas supply device 65 and an exhaust device 66, and a thin first oxide thin film 92 is formed on the surface of the substrate 10 that has been transported. . Because of the reducing atmosphere, the surface of the substrate 10 is not oxidized again when the first oxide thin film 92 is formed. Note that since the formation of the first oxide thin film 92 is intended to form a barrier that prevents oxidation of the substrate surface, the first film formation chamber 60 is formed thin enough to prevent oxygen deficiency. Thus, it is preferable that the reducing atmosphere is weaker than that in the reducing heat treatment chamber 30.

  The substrate 10 on which the first oxide thin film 92 is formed is subsequently transferred to the second film formation chamber 70 via the atmosphere blocking wall 51.

  The second film formation chamber 70 is set in an oxidizing atmosphere by the gas supply device 75 and the exhaust device 76, and on the first oxide thin film 92 formed on the surface of the substrate 10 that has been transferred, A second oxide thin film 93 having a predetermined thickness is formed. Since the first oxide thin film 92 has already been formed on the surface of the substrate 10, the surface of the substrate 10 is not oxidized even in an oxidizing atmosphere. In addition, since there is an oxidizing atmosphere, oxygen vacancies do not occur in the second oxide thin film 93.

(Example)
Hereinafter, the present invention will be specifically described with reference to examples.
A CeO ₂ film was formed on the oriented Ni substrate by using the film forming apparatus according to the third embodiment. At this time, Ar containing 3 mol% of H ₂ is introduced as an atmospheric gas into both the reduction heat treatment chamber and the film formation chamber, and the pressure in the film formation chamber is maintained at 5.2 Pa which is an optimum film formation condition. Then, the gas pressure in the reduction heat treatment chamber was controlled using a gas supply device and an exhaust device, and thereby the partial pressure of H ₂ that is a reducing gas in the reduction heat treatment chamber was adjusted as shown in Table 1. The temperature of the reduction heat treatment was 850 ° C., and the film formation temperature was 650 ° C.

The thin film was evaluated for each formed CeO ₂ film. Specifically, using X-ray diffraction (θ-2θ method), the (200) diffraction peak showing the required (100) orientation and the (111) diffraction peak showing the unfavorable orientation are measured. And the orientation rate was calculated | required with the formula shown below, and it was set as the parameter | index.
Orientation rate = {(200) peak intensity} / {(111) peak intensity + (200) peak intensity}
The results are shown in Table 1.

From Table 1, it can be seen that the higher the atmospheric gas pressure in the reduction heat treatment chamber, the higher the orientation ratio of the CeO ₂ film. This is because, as the partial pressure of the reducing gas H ₂ is increased, the oxide layer on the surface of the Ni alignment substrate is further removed, and the oxide thin film formed on the substrate surface immediately after that, that is, the orientation of the CeO ₂ film This is because the property is improved.

FIG. 5 shows the results of X-ray diffraction performed on a thin film having a H ₂ partial pressure of 0.20 Pa and an orientation rate of 93.1% in the third reduction heat treatment chamber shown in Table 1. As shown in FIG. 5, in the case of this thin film, a slight peak indicating oxygen deficiency was observed at the position indicated by the arrow. This is presumably because the film was formed under a weak reducing atmosphere in which the atmospheric pressure in the film forming chamber was 5.2 Pa.

Next, a CeO ₂ film was formed using the film forming apparatus according to the fourth embodiment. At this time, Ar containing 3 mol% of H ₂ as an atmospheric gas is introduced into both the reduction heat treatment chamber and the first film formation chamber, and the pressure in the reduction heat treatment chamber is set to 6.7 Pa. The pressure was controlled using each gas supply device and exhaust device so as to be 5.2 Pa. Thereby, the reduction heat treatment chamber becomes a reducing atmosphere, and the first film forming chamber becomes a weak reducing atmosphere. In addition, Ar containing 0.5 mol% O ₂ was introduced into the second film formation chamber as an atmospheric gas, and was controlled using a gas supply device and an exhaust device so that the pressure was 2.6 Pa. Thereby, the second film formation chamber becomes an oxidizing atmosphere.

  FIG. 6 shows the result of X-ray diffraction performed on the obtained thin film. As shown in FIG. 6, in the case of this thin film, the peak which shows oxygen deficiency was not seen. In this case, the orientation ratio was 92.9%.

  As described above, the first film forming chamber in the reducing atmosphere and the second film forming chamber in the oxidizing atmosphere are provided as the film forming chambers, and the first barrier layer that prevents the oxidation of the substrate surface in the first film forming process is provided. By forming the first oxide thin film thinly and forming the second oxide thin film on the surface of the first oxide thin film in the second film forming step, an excellent oxide thin film without oxygen deficiency can be obtained. I understand that.

DESCRIPTION OF SYMBOLS 10 Substrate 11 Oxide layer 21 Supply roll 22 Winding roll 30 Reduction heat treatment chamber 31, 41, 61, 71 Heater 35, 45, 65, 75 Gas supply device 36, 46, 56, 66, 76 Exhaust device 40 Film formation chamber 50 , 51, 53, 54 Atmosphere blocking walls 50a, 53a, 54a Small holes 52 Atmosphere blocking chamber 60 First film forming chambers 62, 72, 90 Target 70 Second film forming chamber 91 Oxide thin film 92 First oxide Thin film 93 Second oxide thin film

Claims (5)

Oxidation provided with a film forming chamber for forming an oxide thin film on the surface of the oriented metal substrate conveyed from the reducing heat treatment chamber immediately after the reducing heat treatment chamber for removing the oxide layer on the surface of the long oriented metal substrate An apparatus for forming a thin film,
Between the reduction heat treatment chamber and the film formation chamber, an atmosphere blocking unit is provided that makes the atmosphere of the reduction heat treatment chamber and the film formation chamber substantially independent from each other,
Furthermore, a gas supply mechanism and an exhaust mechanism are provided in each of the reduction heat treatment chamber and the film formation chamber, respectively, and the oxide thin film deposition apparatus.   2. The oxide thin film deposition apparatus according to claim 1, wherein the atmosphere blocking section has an exhaust mechanism. The film formation chamber is composed of a first film formation chamber and a second film formation chamber;
2. The atmosphere blocking portion is provided between the first film forming chamber and the second film forming chamber, and an atmosphere blocking portion is provided to make each atmosphere substantially independent. Item 3. The oxide thin film deposition apparatus according to Item 2. A film forming method for forming an oxide thin film on the surface of a long oriented metal substrate,
In a reduction heat treatment chamber controlled to a predetermined atmosphere, a reduction heat treatment step for removing an oxide layer on the surface of the oriented metal substrate;
The oriented metal substrate from which the oxide layer has been removed is provided immediately after the reduction heat treatment chamber via an atmosphere blocking portion and controlled to a predetermined atmosphere substantially independent of the atmosphere of the reduction heat treatment chamber. A transporting process for transporting to the film forming chamber;
A film forming process for forming an oxide thin film on the surface of the oriented metal substrate conveyed from the reduction heat treatment chamber in the film forming chamber. The film forming step includes
A first film forming step of forming a first oxide thin film on a surface of the oriented metal substrate transported from the reduction heat treatment chamber in a reducing atmosphere in a first film forming chamber;
A transfer step of transferring the oriented metal substrate on which the first oxide thin film has been formed to a second film formation chamber via an atmosphere blocking unit;
The second film formation chamber includes a second film formation step of forming a second oxide thin film on the surface of the first oxide thin film in an oxidizing atmosphere. 5. A method for forming an oxide thin film according to 4.

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