JP2001073151A - Cvd reactor and production oxide superconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CVD reactor capable of uniformizing the temp. inside the reactor, and to provide a method for producing an oxide superconductor by which superconducting characteristics of an oxide superconducting thin film deposited on a long-length base material can be prevented from lowering. SOLUTION: This CVD reactor 10 is at least provided with a reactor 31 in which a gaseous starting material is chemically reacted with the surface of a base material 38 during moving to deposit a thin film, a gas diffusing part 40 for feeding a gaseous starting material to the reactor 31 and an exhaust pipe 70b for exhausting gas in the reactor 31. In the reactor 31, a base material introducing part 34, a reaction producing chamber 35 and a base material discharging part 36 are formed so as to be partitioned by partions 32 and 33, and a main heater 95 for heating the reactor 31 by covering the whole of the reactor 31 and an auxiliary heater 90 provided at the inside of the main heater 95 for heating the reaction producing chamber 35 by covering the whole of the reaction producing chamber 35 are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a CVD reactor for forming a thin film on a substrate, and more particularly to a CVD reactor suitable for forming a thin film on a long substrate. is there.

[0002]

2. Description of the Related Art Conventionally, chemical vapor deposition (CVD) has been used.
Has less restrictions on the shape of the base material than physical vapor deposition (PVD) such as sputtering or vapor deposition such as vacuum deposition.
It is widely known as a technique capable of forming a thin film on a large-area substrate at high speed. However, in this CVD method, the composition and supply rate of the raw material gas, the type of the carrier gas and the supply amount of the reaction gas, or the control of the gas flow in the film forming chamber due to the structure of the reaction reactor, etc. However, it has a disadvantage that it is difficult to optimize the conditions for forming a high-quality thin film using the CVD method because it has many unique control parameters not found in other film forming methods. .

[0003] Conventionally, a CVD method as shown in FIG.
A thin film was formed on a tape-shaped substrate using the reaction device 210. This CVD reactor 210 has a cylindrical reactor 211, and the reactor 211 has partition walls 212, 213.
Thus, it is divided into a base material introduction part 214, a reaction generation chamber 215, and a base material lead-out part 216. Through holes (not shown) through which the tape-shaped base material 218 can pass are formed in the lower centers of the partition walls 212 and 213, respectively. Reaction generation chamber 2
The gas diffusion unit 220 is attached to 15. A supply pipe 220b is connected to the gas diffusion section 220, and raw material gas and oxygen are supplied from the supply pipe 220b to the gas diffusion section 2b.
It can be supplied to the reaction generation chamber 215 through the passage 20.

Further, the reaction generation chamber 21 in the reactor 211
5, an exhaust chamber 217 is provided along the length direction of the tape-shaped base material 218. An elongated gas exhaust hole (not shown) is formed in the upper part of the exhaust chamber 217 along the length direction of the tape-shaped base material 218. In addition, two exhaust pipes 22 are provided below the exhaust chamber 217.
One end of each of the exhaust pipes 3 and 223 is connected, and the other end of each of the exhaust pipes 223 and 223 is connected to a vacuum pump (not shown). The exhaust pipes 223 and 223 are connected to the reactor 21.
1 is provided along the length direction of the tape-shaped base material 218 passed through. The CVD reactor 210 is provided with a cylindrical heater 295 that covers the entire reactor 211. For example, in order to deposit an oxide superconducting thin film on the base material 218, the temperature of the base material 218 is set to 700 to 800.
The temperature inside the reactor 211 is heated by the cylindrical heater 295, and the substrate 218 is indirectly heated to about 700 to 800 ° C.

When a long oxide superconductor is manufactured using the CVD reactor 210, for example, the tape-shaped base material 218 is sequentially fed to the reaction generation chamber 215 while the tape-shaped base material 218 is being fed into the reaction generation chamber 215. A method is employed in which a source gas is chemically reacted on the surface of the base material 218 to deposit an oxide superconducting thin film.

[0006]

The source gas used in the CVD reactor 210 is a gas obtained by heating a gas obtained by dissolving a metal chelate in an organic solvent. ° C, and the gas flow rate is 1 to 3 L / min. Therefore, since the temperature of the raw material gas is lower than the temperature in the reaction generation chamber 215, when the raw material gas is introduced into the reaction generation chamber 215, the reaction generation chamber 2
It is considered that the inside of the substrate 15 is cooled and the temperature of the substrate 218 decreases. In order to prevent this, in the conventional CVD reactor 210, the output of the cylindrical heater 295 is increased to a degree that complements the decrease in the temperature of the reaction generation chamber 215 due to the introduction of the source gas, and the base material 218 in the reaction generation chamber 215 is increased. Is maintained at about 700 to 800 ° C. However, the cylindrical heater 295 is configured to heat the entire reactor 211, and the flow rate of the raw material gas is low near the partition walls 212 and 213 that partition the reaction generation chamber 215, so that the influence of the temperature decrease by the raw material gas is small. , Partition 212, 2
The temperature around 13 is heated to 800 ° C. or higher.

Therefore, in the reactor 211, as shown in FIG. 15, a temperature distribution is generated along the longitudinal direction. That is, in FIG.
The temperature is 800 ° C. almost at the center of the partition wall 2.
In the vicinity of 12, 213, the temperature is 820 to 830 ° C.
Such a temperature distribution is the same in the case of a reactor 311 having three reaction generation chambers 315 as shown in FIG. 16, and as shown in FIG. 16, a temperature distribution occurs in the longitudinal direction of the reactor 311. ing. That is, in FIG. 16, the temperature is 800 ° C. in the central reaction generation chamber 315.
, But the temperature of other parts is 850-900
° C, and especially about 9 near the partition walls 312 and 313.
The temperature was 00 ° C., and the temperature distribution was remarkable.

[0008] Such a temperature distribution of the reactors 211 and 311 is a major problem in continuously producing a long oxide superconductor. For example, as shown in FIG. 15, when the oxide superconducting thin film formed at a temperature of about 800 ° C. in the reaction generation chamber 215 is heated to about 830 ° C. when passing near the partition 213, the oxide superconducting thin film is heated. There has been a problem that the composition of the thin film becomes non-uniform and the superconducting properties of the oxide superconductor deteriorate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides a CVD reactor capable of making the temperature inside a reactor uniform, as well as an oxidation reactor deposited on a long base material. It is an object of the present invention to provide a method of manufacturing an oxide superconductor that can prevent a deterioration in superconducting properties of an object superconducting thin film.

[0010]

According to a first aspect of the present invention, there is provided a CVD reaction apparatus, comprising: a reactor for performing a CVD reaction for depositing a thin film by chemically reacting a raw material gas on a moving tape-shaped substrate surface; A CVD reaction device comprising at least a gas diffusion unit for supplying the source gas, and an exhaust pipe connected to an exhaust port for exhausting gas in the reactor, wherein the reactor has a base material introduction unit and A reaction generation chamber and a base material lead-out section are formed by being partitioned by a partition, a main heater that covers the reactor and heats the entire reactor, and the reaction that is provided inside the main heater and partitioned by the partition. An auxiliary heater that covers the entire production chamber and heats the reaction production chamber is provided.

Further, the CVD reactor according to claim 2 is
A reactor for performing a CVD reaction for depositing a thin film by chemically reacting a source gas on the surface of a moving tape-shaped substrate, a gas diffusion unit for supplying the source gas to the reactor, and exhausting gas in the reactor An exhaust pipe connected to an exhaust port.
In the reactor, a base material introduction section, a reaction generation chamber, and a base material outlet section are formed by being partitioned by partition walls, and a plurality of the reaction generation chambers are provided in series in the moving direction of the tape-shaped base material,
A boundary chamber is provided between each of the reaction generation chambers, and a base material transport region passing through the base material introduction section, the reaction generation chamber, the boundary chamber, and the base material discharge section is formed inside the reactor,
The gas diffusion unit is provided for each of the reaction generation chambers,
A main heater that covers the reactor and heats the entire reactor, and a plurality of auxiliary heaters that are provided inside the main heater and cover and heat the entire reaction generation chambers partitioned by the partition walls, respectively. It is characterized by having.

According to a third aspect of the present invention, there is provided the CVD reactor as described above, further comprising temperature control means capable of independently controlling the temperature of each of the auxiliary heaters. Features. Further, in the CVD reactor according to claim 2 or 3, a plurality of source gas supply units connected to the respective gas diffusion members, a gas exhaust unit connected to the exhaust pipe, and the respective source gases A supply unit and a control unit that controls the gas exhaust unit, and the source gas supply unit includes the source gas supply source,
An oxygen gas supply unit is provided, and each of the source gas supply units is independently controlled by the control unit, and an oxygen partial pressure in the source gas supplied to each of the reaction generation chambers is independently controlled. Preferably, it is controllable.

According to a fourth aspect of the present invention, there is provided a method of manufacturing an oxide superconductor using the above-described CVD reactor, wherein the temperature of the reaction generating chamber is controlled by introducing a raw material gas. When the temperature decreases, the source gas is chemically reacted with the tape-shaped base material while controlling the auxiliary heater so that the temperature in the reaction generation chamber is made equal to the temperature near the partition partitioning the reaction generation chamber. And depositing an oxide superconducting thin film.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention, C
The VD reactor will be described with reference to the drawings. 1 and 2
The first embodiment of the present invention is a CVD reactor 1
Indicates 0. FIGS. 3 and 4 show the detailed structures of the reactor 31 and the gas diffusion unit 40 which mainly constitute the CVD reaction apparatus 10.

As shown in FIGS. 1 to 4, the CVD reactor 10 has a tubular quartz reactor 31 having both horizontally long ends closed.
And the reaction generation chamber 35 and the base material lead-out portion 36
3 are formed. The material constituting the reactor 31 is not limited to quartz, but may be a metal having excellent corrosion resistance such as stainless steel.

At the lower center of the partition walls 32 and 33, there are formed through holes 39 through which a long tape-shaped base material 38 can pass. , A substrate transport region R is formed. Further, an introduction hole for introducing the tape-shaped base material 38 is formed in the base material introduction part 34, and a lead-out hole for leading the base material 38 is formed in the base material lead-out part 36. At the periphery of the hole and the lead-out hole, the gap between the holes is closed while the base material 38 is passed, and the base material introduction part 34 and the base material lead-out part 36 are closed.
Is provided with a sealing mechanism (not shown) for keeping the airtight state.

A flared truncated pyramid-shaped gas diffusion section 40 is attached to the ceiling of the reaction generation chamber 35. The gas diffusion unit 40 includes trapezoidal side walls 41, 41 arranged along the longitudinal direction of the reactor 31, a front wall 42 and a rear wall 43 connecting these side walls 41, 41 to each other, and a ceiling wall 44. The gas diffusion member 45 is mainly constituted. Further, a supply pipe 53 for supplying a source gas is connected to the ceiling wall 44 of the gas diffusion member 45. In addition, the bottom surface of the gas diffusion member 45 is formed as an elongated rectangular opening 46, and the gas diffusion member 45 and the reaction generation chamber 35 are configured to communicate with each other through the opening 46.

As shown in FIGS. 1 and 2, the CVD reactor 10 includes a cylindrical auxiliary heater 90 for heating the reaction generation chamber 35 of the reactor 31 and a cylindrical main heater for heating the entire reactor 31. 95 are provided. Further, as shown in FIG.
5 is provided with a cylindrical heat insulating material 98. The main heater 95 and the auxiliary heater 90 are connected to separate temperature control means, respectively, and are configured to be independently temperature-controlled.

The auxiliary heater 90 is located substantially at the center in the longitudinal direction of the reactor 31 and is arranged so as to cover at least the reaction generating chamber 35 located between the partition walls 32 and 33. The auxiliary heater 90 includes two side heaters 91 and 9.
2 are abutted against each other so as to sandwich the reactor 31 from both sides in the traveling direction of the tape-shaped base material 38. These side heaters 91 and 92 are formed by rounding and forming a small sheet-shaped heater 93 shown in FIG. 5 into a semi-cylindrical shape, and one ends 91a and 92a of the side heaters 91 and 92 respectively include: Substantially rectangular notches 91b and 92b
Are provided, and when the side heaters 91 and 92 are joined to the reactor 31, the gas diffusion members 45 protruding above the reactor 31 are provided with these cutout portions 91 b,
The side heaters 91 and 92 and the gas diffusion member 45 are configured so as not to interfere with each other by being fitted to the base 92b.

As shown in FIG. 5, for example, as shown in FIG. 5, a sheet-type small heater 93 constituting the side heaters 91 and 92 is formed by bending a linear resistance heating element 93a into a folded shape. The resistance heating element 93a is preferably made of, for example, a Kanthal wire (Fe-Cr-Al-based alloy).

The main heater 95 is disposed so as to cover the auxiliary heater 90 and the reactor 31, as shown in FIGS. The main heater 95 is configured such that an upper heater 96 and a lower heater 97 abut each other so as to sandwich the reactor 31 from above and below. The upper heater 96 and the lower heater 97 are formed by rounding the sheet-type large heaters 96a and 97a shown in FIGS. 6 and 7, respectively, into a semi-cylindrical shape. A square hole 96b is provided substantially at the center of the upper heater 96, and when the upper heater 96 is joined to the reactor 31, the gas diffusion member 45 protruding above the reactor 31 passes through the square hole 96b. The upper heater 96 and the gas diffusion member 45 do not interfere with each other. Further, the lower heater 97 is provided with two round holes 97b, 97b, and when the lower heater 97 is joined to the reactor 31, the two exhaust pipes 70b, 70b projecting below the reactor 31 are provided.
Are configured to penetrate through the round holes 97b, 97b so that the lower heater 97 does not interfere with the exhaust pipes 70b, 70b.

The large sheet heaters 96a and 97a constituting the upper heater 96 and the lower heater 97 are, for example, linear resistance heating elements 96 as shown in FIGS.
d and 97d are bent in a zigzag manner, and are arranged so as to be uniformly distributed over the entire surface of the heat resistant sheets 96c and 97c.
For d, for example, a nichrome wire (Ni-Cr alloy) is preferably used.

As shown in FIG. 2, the heat insulating material 98 is composed of an upper heat insulating material 98a and a lower heat insulating material 98b butted against each other so as to sandwich the reactor 31 from above and below. These upper heat insulating material 98a and lower heat insulating material 98b
Is formed by rolling a sheet-like heat insulating material into a semi-cylindrical shape. A square hole 98c is provided substantially at the center of the upper heat insulating material 98a, and when the upper heat insulating material 98a is joined to the reactor 31, the gas diffusion member 45 protruding above the reactor 31 penetrates the square hole 98c. Thus, the upper heat insulating material 98a and the gas diffusion member 45 are configured so as not to interfere with each other. The lower heat insulator 98b is provided with two round holes 98d, 98d.
Are joined to the reactor 31, two exhaust pipes 70b, 70b projecting below the reactor 31
8d and 98d, the lower heat insulating material 98b and the exhaust pipe 7
0b and 70b do not interfere with each other.

Since the main heater 95 is disposed so as to cover the entire reactor 31, the base material introduction section 34, the reaction generation chamber 35 and the base material outlet section 36 are simultaneously heated by the main heater 95. Further, since the auxiliary heater 90 is disposed so as to cover the reaction generation chamber 35, the reaction generation chamber 35 is also heated by the auxiliary heater 90. Therefore, the reaction generation chamber 35 is heated by the auxiliary heater 90 and the main heater 95, and the amount of heat applied to the reaction generation chamber 35 is
The amount of heat is larger than the amount of heat applied to the base material introduction part 34 and the base material outlet part 36. Further, although the Kanthal wire is preferably used for the resistance heating element 93a incorporated in the auxiliary heater 90, this Kanthal wire is higher in temperature than the Nichrome wire preferably used as the resistance heating elements 96d and 97d of the main heater 95. The reaction generation chamber 3
The amount of heat applied to 5 is greater.

Next, an exhaust chamber 70 is provided below the reaction generation chamber 35 of the reactor 31 along the length direction of the substrate transport region R as shown in FIG. As shown in FIG. 4, an elongate rectangular shape is formed in the upper part of the exhaust chamber 70 so as to be located on both sides along the length direction of the tape-shaped substrate 38 passed through the substrate transport region R. Gas exhaust holes 70a,
70a are respectively formed. Also, one end of each of a plurality of (two in the drawing) exhaust pipes 70b is connected to a lower portion of the exhaust chamber 70, while the other end of each of the plurality of exhaust pipes 70b is connected to a pressure provided with a vacuum pump. It is connected to an adjusting device (not shown). As shown in FIG. 3, the exhaust ports 70 c of the plurality of exhaust pipes 70 b extend along the length direction of the tape-shaped base material 38 passed through the base material transport region R along the base of the exhaust chamber 70. The end bottom surface on the side of the material introduction part 34 and the end bottom surface on the side of the base material lead-out part 36 are respectively provided. Therefore, the exhaust chamber 70 in which the gas exhaust holes 70a, 70a are formed, and the plurality of exhaust pipes 70 having the exhaust ports 70c
b ... and a pressure adjusting device (not shown) constitute a gas exhaust means. The gas exhaust means having such a configuration is C
A gas such as a source gas, an oxygen gas, or an inert gas inside the VD reactor 10 can be exhausted from the gas exhaust holes 70a, 70a through an exhaust chamber 70, an exhaust port 70c, and an exhaust pipe 70b.

A source gas supply source (not shown) is connected to the supply pipe 53 of the CVD reactor 10. The source gas supply source includes, for example, a source solution tank, a carrier gas supply device, and a vaporizer connected to the source solution tank and the carrier gas supply device.
A raw material solution containing a metal complex and a carrier gas are supplied to the vaporizer while being heated to about 300 ° C., and the raw material gas is generated by spraying the raw material solution into the carrier gas to supply the raw material gas. It is configured so that it can be supplied to the CVD reactor 10 via the tube 53. The temperature of the source gas generated here is about 200 to 300 ° C. An oxygen gas supply source (not shown) is branched and connected to an intermediate portion of the supply pipe 53 so that oxygen gas can be supplied to the raw material gas passing through the supply pipe 53.

Next, a method for forming a thin film on a tape-shaped substrate 38 using the above-described CVD reactor 10 will be described.
To form a thin film using the above-described CVD reactor 10, first, a tape-shaped base material 38 and a raw material solution are prepared.
As the base material 38, a long one can be used,
A heat-resistant metal tape having a low coefficient of thermal expansion is particularly often used. The constituent materials of the metal tape include silver, platinum,
Metal materials and alloys such as stainless steel, copper, and Hastelloy (such as C276) are preferable. Also, except for metal tape,
Tapes made of various ceramics such as various glass tapes or mica tapes may be used. Further, an intermediate layer may be formed on the base material 38 in advance depending on the type of the thin film to be formed. For example, when the thin film to be formed is an oxide superconducting thin film, it is preferable to cover the base material 38 with a ceramic intermediate layer in order to adjust the crystal orientation of the oxide superconducting thin film. The material constituting the intermediate layer is YSZ (yttrium-stabilized zirconia), SrTiO ₃ , Mg whose thermal expansion coefficient is closer to that of the oxide superconducting thin film than metal.
O, Al ₂ O ₃ , LaAlO ₃ , LaGaO ₃ , YAl
Ceramics such as O ₃ and ZrO ₂ are preferable, and among them, it is preferable to use ceramics having as good a crystal orientation as possible.

Next, the raw material solution for forming the thin film by the CVD reaction is preferably a solution in which a metal complex of each element constituting the thin film is dispersed in a solvent. For example, when an oxide superconducting thin film is to be formed as a thin film, more specifically, Y is widely known as a composition of Y ₁ Ba ₂ Cu ₃ O _7-x.
When forming a system oxide superconducting thin film, Ba-bis-
2,2,6,6-tetramethyl-3,5-heptanedione-bis-1,10-
Phenanthroline (Ba (thd) ₂ (phen) ₂ )
, Y (thd) ₂ , Cu (thd) _2, etc., and Y-bis-2,2,6,6-tetramethyl-
3,5-Heptane dionate (Y (DPM) ₃ ) and Ba
(DPM) ₂ and Cu (DPM) ₂ can be used.

The oxide superconducting thin film includes, in addition to the Y-based thin film, a La-based material represented by a composition of La _2-x Ba _x CuO ₄ ,
_{Bi 2 Sr 2 Ca n-1} Cu n O 2n + 2 Bi system (n is a natural number) is represented by the composition _{of, Tl 2 Ba 2 Ca n-} 1 Cu n O 2n + 2 (n
Since various types of oxide superconducting thin films such as Tl-based thin films represented by the composition of (natural number) are known, the CVD method may be performed using a metal complex salt according to the desired composition. Here, for example, in the case of manufacturing an oxide superconducting thin film other than Y-based, depending on the required composition system, triphenylbismuth (III), bis (dipivaloymethanato) strontium (II), bis (di Pivaloymethanato) calcium (II), tris (dipivaloymethanato) lanthanum (I
II), etc., can be used for the production of each type of oxide superconducting thin film by appropriately using a metal complex salt.

After the tape-shaped substrate 38 is prepared, it is fed into the substrate transport region R in the CVD reactor 10 from the substrate introduction section 34 at a predetermined moving speed. Is heated to about 700 ° C. to 800 ° C. by the auxiliary heater 90 and the main heater 95.

Before the substrate 38 is fed, an inert gas is sent into the CVD reactor 10 as a purge gas, and at the same time, the gas inside the CVD reactor 10 is sent to the gas exhaust holes 70a, 70a through the exhaust chamber 70, the exhaust port 70c, and the exhaust pipe 70b.
It is preferable to clean the inside of the VD reactor 10 by eliminating unnecessary gas such as air.

If the base material 38 is sent into the CVD reactor 10, if the thin film to be formed is an oxide superconducting thin film, oxygen gas is sent into the CVD reactor 10 and the oxygen gas is further fed into the above-mentioned source gas supply source. The raw material solution and the carrier gas are supplied to a vaporizer to generate a raw material gas. Furthermore, CV
The gas inside the D reactor 10 is supplied to the gas exhaust holes 70a, 70
The gas is exhausted from a through the exhaust chamber 70, the exhaust port 70c, and the exhaust pipe 70b, and the inside of the CVD reactor 10 is set to a negative pressure. And
The source gas is supplied to the gas diffusion unit 40 via the supply pipe 53. The source gas is a CVD reactor 1 having a negative pressure inside.
It is pulled into 0. At the same time, an operation of supplying oxygen gas from the above-described oxygen gas supply source (not shown) branched and connected to the supply pipe 53 to mix oxygen into the source gas is also performed.

Next, inside the CVD reactor 10, the raw material gas that has entered the gas diffusion section 40 from the supply pipe 53 diffuses along the ceiling wall 44, the front wall 42, and the rear wall 43 of the gas diffusion section 40. While moving to the reaction generation chamber 35 side. The source gas diffused in the gas diffusion unit 40 passes through the inside of the reaction generation chamber 35 while further diffusing along the front wall 42 and the rear wall 43 of the gas diffusion unit 40, and then passes through the base material 3.
8 so that the gas exhaust holes 70a, 7
By moving the substrate so as to be drawn into Oa, the source gas reacts on the upper surface side of the heated base material 38 to deposit a reaction product.

Here, when the source gas is introduced into the reaction generation chamber 35, the atmosphere in the reaction generation chamber 35 is cooled because the temperature of the source gas is lower than the temperature of the atmosphere in the reaction generation chamber 35. Although the temperature of the base material 38 tends to decrease, the reaction generation chamber 35 is heated by the main heater 95 and the auxiliary heater 90, and the amount of heat received from these heaters 90, 95 is large. Even in this case, the temperature of the atmosphere in the reaction generation chamber 35 does not decrease, and the temperature of the substrate 38 is maintained at 700 to 800 ° C., which is the optimum temperature for performing the CVD reaction. In addition, the reaction generation chamber 3
In the vicinity of the partition walls 32 and 33 which define the main heater 95, the temperature of the main heater 95 does not decrease without being affected by the raw material gas.
Only between the reaction generation chamber 35 and the vicinity of the partition walls 32 and 33, the temperature becomes constant and a temperature distribution occurs, as shown in FIG. Absent. Therefore, when the substrate 38 on which the oxide superconducting thin film is formed moves from the reaction generation chamber 35 to the vicinity of the partition wall 33, it is not heated to a temperature exceeding 800 ° C. It does not drop.

The above-described CVD reactor 10 includes a cylindrical main heater 95 for heating the entire reactor 31 and a reactor 3.
An auxiliary heater 90 for heating only one reaction generation chamber 35 is provided, and the amount of heat given to the reaction generation chamber 35 is made larger than the amount of heat given to the base material introduction part 34 and the base material discharge part 36. Therefore, even if the raw material gas is introduced into the reaction generation chamber 35, the temperature in the reaction generation chamber 35 does not decrease and the temperature distribution inside the reactor 31 is kept constant.
Even when the base material 38 passes through the reaction generation chamber 35 and reaches the vicinity of the partition wall 33, the temperature of the base material 38 does not increase, and a decrease in the superconducting characteristics of the oxide superconductor can be prevented.

The residual gas after the reaction can be exhausted from the gas exhaust holes 70a... Disposed on the side of the substrate 38 through the exhaust chamber 70, the exhaust port 70c, and the exhaust pipe 70b. In addition, there is little possibility that the residual gas reaches the base material outlet 36 side. Therefore, a thin film, a deposit, or a reaction product having a composition different from the target composition is deposited on the base material introduction part 34 side or on the base material discharge part 36 due to the residual gas.
It will not be generated on the side. Further, when the thin film to be formed contains oxygen as in the case of an oxide superconducting thin film, the oxygen gas is sent to the base outlet section 36 at the time of film formation, and the oxygen gas is mixed with the raw material gas. Since oxygen is supplied to the oxide superconducting thin film on 38 and oxygen is supplied to the oxide superconducting thin film as much as possible, an oxide superconducting thin film having better film quality can be obtained.

Next, the CV according to the second embodiment of the present invention will be described.
The D reactor will be described with reference to the drawings. 9 and 10
Is a CVD reactor 1 according to a second embodiment of the present invention.
10 is shown. FIGS. 11 and 12 show this CVD.
2 shows a detailed structure of a reactor 131 and a gas diffusion section 140 which mainly constitute the reactor 110.

As shown in FIGS. 9 and 10, this CVD reactor 110 has three CVs having substantially the same structure.
D units A, B, and C are incorporated, and an oxide superconducting thin film is formed on a tape-shaped substrate 38 in the CVD units A, B, and C.

The CVD reactor 110 is shown in FIGS.
As shown in FIG. 3, a cylindrical quartz reactor 131 having horizontally long ends closed is provided.
The base material introduction part 13 is sequentially arranged from the left side of FIG.
4, the reaction generation chamber 135, and the base material outlet 136, and the partition 137 defines the reaction generation chamber 135.
Is divided into three parts, each of which is the aforementioned CVD unit A,
Each of the reaction generation chambers 135 constitutes a part of B and C.
, Boundary chambers 138 and 138 are partitioned and provided. The material forming the reactor 131 is not limited to quartz, but may be a metal having excellent corrosion resistance such as stainless steel.

At the lower center of the partition walls 132, 133, 137,..., As shown in FIG. , A substrate transport region R is formed so as to cross the center of the substrate. Further, the base material introduction part 13
4, an introduction hole for introducing the tape-shaped base material 38 is formed, and a lead-out hole for leading out the base material 38 is formed in the base-material lead-out portion 136. The part is provided with a sealing mechanism (not shown) that closes the gap between the holes and keeps the base material introduction part 134 and the base material derivation part 136 in an airtight state while the base material 38 is passed through. .

Further, as shown in FIGS. 9 and 10, three truncated pyramid-shaped gas diffusion portions 140 are attached to the ceiling of each reaction generation chamber 135. As shown in FIG. Gas diffusion unit 140
Are trapezoidal side walls 141, 141 arranged along the longitudinal direction of the reactor 131, and these side walls 141, 141.
A front wall 142 and a rear wall 143 interconnecting the
A supply pipe 15 mainly composed of a gas diffusion member 145 composed of a ceiling wall 144 and further connected to the ceiling wall 144
3 is provided. As shown in FIG. 11, a slit nozzle 153 is provided at the tip of the supply pipe 153.
a is provided. As shown in FIG. 9, the bottom surface of the gas diffusion member 145 is formed with rectangular openings 146, and through the openings 146, the gas diffusion members 145 are formed.
And the reaction generation chambers 135 are configured to communicate with each other.

As shown in FIGS. 9 to 11, the boundary chamber 138
In the ceiling portion of the gas supply means 138B, a supply pipe 13 is provided.
8A, the shut-off gas supply means 138B
A shut-off gas for shutting off the reaction generation chambers 135 and 135 on both sides of the boundary chamber 138 is supplied, and a connection portion of the supply pipe 138A is connected via a shut-off gas ejection part 138a, and, for example, argon gas is selected as the shut-off gas. Is done.

As shown in FIG. 9 and FIG.
Each reaction generation chamber 1 of the reactor 131 is
Three cylindrical auxiliary heaters 190 for heating 35...
A cylindrical main heater 195 for heating the entire reactor 131 is provided. Further, as shown in FIG.
The reactor 110 is provided with a cylindrical heat insulating material 198 that covers the main heater 195. Three auxiliary heaters 190 ...
As shown in FIG. 10, is connected to a temperature control means 183 so that each auxiliary heater 190 is independently controlled in temperature.

The three auxiliary heaters 190...
Are arranged so as to cover three reaction generation chambers 135 divided by 2, 133, 137, respectively.
The auxiliary heater 190 has two side heaters 191, 192.
The reactor 1 from both sides of the tape-shaped base material 38 in the traveling direction.
31 are sandwiched between each other. These side heaters 191 and 192 are formed by rounding a small sheet type heater into a semi-cylindrical shape,
One end 191 of each of the side heaters 191 and 192
a, 192a are the side walls 141, 1 of the gas diffusion member 145.
41 and the other end 191b, 192b
Are matched to each other.

The small sheet heaters constituting the side heaters 191 and 192 have substantially the same structure as the small sheet heater 93 shown in FIG. 5 described above, and a linear resistance heating element is bent in a zigzag manner. These are arranged so as to be uniformly distributed over the entire surface of the heat-resistant sheet. The resistance heating element includes, for example, a Kanthal wire (Fe—Cr—Al alloy).
Is preferably used.

As shown in FIGS. 9 and 10, the main heater 195 comprises three auxiliary heaters 190 and a reactor 131.
It is arranged to cover. This main heater 195 is
The upper heater 196 and the lower heater 197 are configured to abut each other so as to sandwich the reactor 131 from above and below. The upper heater 196 and the lower heater 197 are each formed by shaping a large sheet-type heater into a semi-cylindrical shape. As shown in FIG.
The upper heater 196 is provided with three square holes 196b. When the upper heater 196 is joined to the reactor 131, the gas diffusion member 145 protruding above the reactor 131 passes through the square hole 196b. , Upper heater 19
6 and the gas diffusion member 145 do not interfere with each other. The lower heater 197 has four round holes 19.
Are provided, and when the lower heater 197 is joined to the reactor 131, the four exhaust pipes 170b projecting below the reactor 131 pass through the respective round holes 197b. And the exhaust pipes 170b... Do not interfere with each other.

The large sheet heaters constituting the upper heater 196 and the lower heater 197 have substantially the same structure as the large sheet heaters 96a and 97a shown in FIGS. 6 and 7, respectively. Are folded in a zigzag manner, and are arranged so that they are uniformly distributed over the entire surface of the heat-resistant sheet.
For example, a nichrome wire (Ni-Cr alloy) is preferably used.

The heat insulating material 198 is configured such that an upper heat insulating material 198a and a lower heat insulating material 198b abut each other so as to sandwich the reactor 131 from above and below. The upper heat insulating material 198a and the lower heat insulating material 198b are formed by rolling a sheet-shaped heat insulating material into a semi-cylindrical shape. As shown in FIG. 10, the upper heat insulator 198a is provided with three square holes 198c.
When 98a is joined to the reactor 131, the reactor 1
Gas diffusion member 145 projecting above
The upper heat insulating material 198a and the gas diffusion member 145 are configured so as not to penetrate through the gas diffusion member 98c. The lower heat insulating material 198b is provided with four round holes 198d. When the lower heat insulating material 198b is joined to the reactor 131, four exhaust pipes 170b projecting below the reactor 131 are provided. Are configured to penetrate through the round holes 198d so that the lower heat insulating material 198b and the exhaust pipes 170b do not interfere with each other.

Since the main heater 195 is disposed so as to cover the entire reactor 131, the base material introduction part 134, three reaction generation chambers 135, boundary chambers 138 and 138, and the base material outlet part 136 are controlled by the main heater 195. Heated at the same time. Also, three auxiliary heaters 190...
Are arranged so as to cover the respective reaction generating chambers 135, and are also heated by the auxiliary heaters 190. Therefore, the respective reaction generation chambers 135 are heated by the auxiliary heaters 190 and the main heater 195, and the amount of heat applied to each reaction generation chamber 135 is the base material introduction part 134, the boundary chambers 138, 138 and Substrate lead-out section 13
6 is greater than the amount of heat applied. Although a Kanthal wire is preferably used as a resistance heating element incorporated in each of the auxiliary heaters 190, this Kanthal wire is used at a higher temperature than a Nichrome wire preferably used as a resistance heating element of the main heater 195. , The amount of heat applied to each of the reaction generation chambers 135 becomes larger.

Next, below the reaction generation chambers 135 and the boundary chambers 138 and 138, along the length direction of the substrate transfer region R, as shown in FIG.
And an exhaust chamber 170 is provided so as to penetrate through the boundary chambers 138. In the upper part of the exhaust chamber 170, FIG.
As shown in FIG. 3, rectangular gas exhaust holes 170a, 170a which are elongated along the length direction of the tape-shaped base material 38 passed through the base material transport region R, form each reaction generation chamber 135 ... and boundary chamber 138 ... Each is formed so as to penetrate.

One end of each of a plurality of (four in the drawing) exhaust pipes 170b is connected to the lower portion of the exhaust chamber 170, while the other end of each of the plurality of exhaust pipes 170b is connected to a vacuum pump. Is connected to a pressure adjusting device (not shown) provided with Also, as shown in FIGS. 11 and 12, the exhaust ports 170c, 17 of the plurality of exhaust pipes 170b.
0e is a tape-shaped substrate 38 passed through the substrate transport region R.
The exhaust port 170c is provided upstream of the partition 132 in the longitudinal direction of the tape-shaped substrate 38 passed through the substrate transport region R in the exhaust chamber 170 and downstream of the partition 133. And the exhaust port 170e is located in the boundary chamber 1
The tape-shaped base material 38 is extended in the length direction of the tape-shaped base material 38 passed through the base material transport region R so as to be located over the partition walls 137 and 137 on both sides of the base material 38.

As described above, the gas exhaust holes 170a, 170
exhaust chamber 170 in which a is formed, and exhaust ports 170c and 17
A gas exhaust means is constituted by a plurality of exhaust pipes 170b. The gas exhaust means having such a structure is provided by the CVD reactor 110
A gas such as a raw material gas, an oxygen gas, an inert gas, and a shut-off gas is supplied from the gas exhaust holes 170a, 170a to the exhaust chamber 170,
b ... can be exhausted.

Each supply pipe 15 of the CVD reactor 110
3 are connected to source gas supply sources (not shown). The source gas supply source is, for example, a source solution tank, a carrier gas supply device, and a vaporizer connected to the source solution tank and the carrier gas supply device,
While heating the vaporizer to about 100 to 300 ° C., the raw material solution containing the metal complex and the carrier gas are supplied to the vaporizer, and the raw material solution is generated by spraying the raw material solution into the carrier gas. The source gas is configured to be supplied to each gas diffusion section 140 of the CVD reactor 110 via each supply pipe 153. The temperature of the generated source gas is set to 200 to 300 ° C. An oxygen gas supply source (not shown) is branched and connected to an intermediate portion of each of the supply pipes 153.
Are supplied so that oxygen gas can be supplied to the source gas passing through.

Next, a method of forming a thin film on the tape-shaped base material 38 using the above-described CVD reactor 110 will be described. In order to form a thin film using the above-described CVD reactor 110, first, a tape-shaped base material 38 and a raw material solution are prepared. As the base material 38, the same material as described above can be used. As the raw material solution, for example, when the thin film to be formed is an oxide superconducting thin film, the same solution as described above can be used.

After the tape-shaped base material 38 is prepared, it is fed into the base material transport region R in the CVD reactor 110 from the base material introduction portion 134 at a predetermined moving speed. The substrate 38 is divided into three auxiliary heaters 190.
.. And the main heater 195 to about 700 ° C. to 800 ° C.

Before the base material 38 is fed, an inert gas is fed into the CVD reactor 110 as a purge gas, and a shut-off gas is sent into each of the boundary chambers 138 and 138 via a shut-off gas jetting part 138a. CVD
The gas inside the reactor 110 is adjusted to a pressure regulator (not shown)
By removing the gas from the gas exhaust holes 170a, 170a through the exhaust chamber 170, the exhaust ports 170c, 170e, the exhaust pipe 170b, etc., it is possible to eliminate unnecessary gas such as air in the CVD reactor 110 and clean the inside thereof. preferable.

After the substrate 38 has been fed into the CVD reactor 110, oxygen gas is fed into the CVD reactor 110, and the raw material solution and the carrier gas are supplied to the vaporizer at the above-mentioned raw material gas supply source. To generate a source gas. Further, the gas inside the CVD reactor 110 is discharged from the gas exhaust holes 170a, 170a through the exhaust chamber 170 and the exhaust port 17a.
0c, exhaust through the exhaust pipe 170b,
Negative pressure is applied to 10. Then, the raw material gas is supplied to each of the gas diffusion units 140 through each of the supply pipes 153. The source gas is drawn into the CVD reactor 110, the inside of which has a negative pressure. At the same time, an operation of supplying oxygen gas from the above-described oxygen gas supply source (not shown) branched and connected to each supply pipe 153 to mix oxygen into the source gas is also performed.

Next, in the inside of the CVD reactor 110, the raw material gas which has flowed out of each supply pipe 153 to each gas diffusion section 140 is supplied to the front wall 142 and rear wall 143 of each gas diffusion section 140. Move toward the respective reaction generation chambers 135... While being diffused along, pass through the insides of the respective reaction generation chambers 135... And then move vertically across the base material 38 to be drawn into the gas exhaust holes 170 a, 170 a. As a result, the raw material gas reacts on the upper surface side of the heated base material 38 to deposit a reaction product.

Here, the raw material gas is supplied to each reaction producing chamber 135.
Is introduced into the reaction chamber 135,
... Because it is lower than the temperature of the atmosphere in the
Are cooled, and the temperature of the base material 38 tends to decrease.
5 and the auxiliary heaters 190..., And receive a large amount of heat from these heaters 190, 195.
The temperature of the atmosphere of 35...
Is the optimal temperature for performing the CVD reaction.
It is kept at 800 ° C.

Further, the vicinity of the partition walls 132, 133, 137,... Dividing the respective reaction generating chambers 135,...
5 and is maintained at a temperature of 700 to 800 ° C., and the respective reaction generation chambers 135.
There is no temperature distribution between 37 and the vicinity. Therefore, the substrate 38 on which the oxide superconducting thin film is formed
Are not heated to a temperature exceeding 800 ° C. when they are moved from the reaction generation chambers 135 to the vicinity of the partition walls 133, 137,..., So that the characteristics of the oxide superconducting thin film do not deteriorate.

Since the set temperatures of the auxiliary heaters 190 can be set independently by the temperature control means 183, for example, as shown in FIG.
By setting the temperature of the D unit A to 800 ° C., the temperature of the CVD unit B to 810 ° C., and the temperature of the CVD unit C to 820 ° C., the temperature is set to gradually increase as the base material 38 advances. In this case, an oxide superconducting thin film having a uniform composition is formed, and the superconducting properties of the oxide superconductor can be further improved.

When depositing the reaction product on the base material 38, the above-mentioned pressure adjusting device (not shown) allows the gas exhaust holes 170a, 170a to pass through the exhaust chamber 170 and the exhaust port 170.
c, 170e, exhausting through the exhaust pipes 170b, and adjusting the gas flow in each of the exhaust pipes 170b, so that the raw material in the length direction of the tape-shaped substrate 38 moving in the substrate transport region R The CVD reaction is performed while controlling the gas flow state. At the same time, the shut-off gas is supplied to the boundary chamber 138 by the shut-off gas supply means 138B, and the gas exhaust holes 170
a, 170a through the exhaust chamber 170, the exhaust port 170e, the exhaust pipe 170b,.
5 and 135 are shut off to maintain the independence of the gas state such as the oxygen partial pressure in each of the reaction generation chambers 135.

During the progress of the reaction in the CVD reactor 110, the flow state of the gas such as the source gas and the oxygen gas in the length direction of the tape-shaped substrate 38 moving in the substrate transport region R May change and adversely affect the oxide superconducting thin film. Therefore, a change in the gas flow rate is measured by a flow meter provided in the substrate transport region R of the reactor 131, and based on the measurement result, The amount of oxygen gas supplied to the CVD reactor 110 is adjusted so that the gas flow state is controlled to be always a preferable flow state, whereby the distribution and composition of the thickness in the length direction of the tape-like base material 38 are reduced. A uniform oxide superconducting thin film can always be formed.

In the above-described CVD reactor 110, a plurality of reaction generating chambers 135 are provided in the reactor 131 in series in the direction in which the tape-shaped base material 38 moves, so that a plurality of CVD processes are performed.
The reaction can be performed continuously, so that the formation rate of the thin film and the thickness of the formed thin film can be improved as compared with the case where only one reaction generation chamber is manufactured.

Further, the reactor 131 includes the reactor 13.
1, a main heater 195 for heating the whole,
And auxiliary heaters 190 for heating the respective reaction generating chambers 135 separately. The amounts of heat given to the respective reaction generation chambers 135 are given to the base material introduction portions 134, the boundary chambers 138, 138, and the base material outlet portions 135. , The temperature distribution inside the reactor 131 is kept constant even if the source gas is introduced into each of the reaction generation chambers 135. Then, the base material 38 passes through the reaction generation chamber 135 and the partition walls 137, 137
Alternatively, the temperature of the base material 38 does not increase even when the temperature reaches the vicinity of the partition wall 123, so that a decrease in the characteristics of the oxide superconductor can be prevented. In addition, the adjacent reaction generation chamber 13
Since the boundary chamber 138 is provided between the first and second reaction chambers 135 and 135, the shut-off gas is supplied to the first and second reaction chambers 135 and 135. The thin film forming conditions such as the internal reaction gas concentration and the oxygen partial pressure can be set independently.

Further, each of the auxiliary heaters 190... Is independently controlled by the temperature control means 138 so that each of the reaction producing chambers 1.
Since the temperature of the base material 38 in each of the reaction generating chambers 35 can be controlled independently and independently,
8 can be arbitrarily changed, and the conditions of the CVD reaction in each of the reaction generation chambers 135... Can be varied. For example, an oxide superconducting thin film is formed on the base material 38 to form an oxide superconductor. If you want to get
An oxide superconducting thin film can be formed under optimal conditions in each of the reaction generating chambers 135, and the superconducting characteristics of the oxide superconductor can be further improved.

Further, the above-described CVD reactor 110 controls the CV while controlling the flow state of the gas such as the source gas and the oxygen gas in the length direction of the substrate 38 moving in the substrate transport region R.
Since the D reaction can be performed, an oxide superconducting thin film having a uniform thickness distribution and uniform composition in the length direction of the tape-like base material 38 can be formed, and superconducting characteristics such as critical current density can be excellent. Oxide superconductor can be produced efficiently.

In the above-described CVD reactor 110, an apparatus has been described in which a horizontally long reactor 131 is used and each reaction generation chamber 135 is connected to a horizontal position. As long as the flow state of the base material gas can be controlled, the reactor may be not only horizontal but also vertical, and the flow direction of the raw material gas is not limited to the vertical direction but may be the horizontal direction or the oblique direction. It goes without saying that the direction in which the material is conveyed may be either the horizontal direction or the vertical direction. Further, the shape of the reactor itself is not limited to a cylindrical shape, and it is a matter of course that any shape such as a box type, a container type, and a spherical continuous type may be used. The above-described CVD reactor 110 can be suitably used for an apparatus for manufacturing an oxide superconductor. Further, the method for producing an oxide superconductor of the present invention can be suitably used for a method for producing an oxide superconductor.

[0069]

EXAMPLES (Example 1) In order to form a Y-based oxide superconducting thin film known as a composition Y ₁ Ba ₂ Cu ₃ O _7-x ,
As raw material solutions for VD, Ba-bis-2,2,6,6-tetramethyl-3,5-heptanedione-bis-1,10-phenanthroline (Ba (thd) ₂ (phen) ₂ ) and Y ( thd) ₂
And Cu (thd) ₂ . Each of these is Y: B
a: Cu = 1.0: 1.9: 2.7 mixed at a molar ratio,
What was added to tetrahydrofuran (THF) so as to be 3.0% by weight was used as a raw material solution.

The tape-shaped base material is a type of Ni alloy.
Stelloy C276 (a product of Haynes Stellite Co., USA
By name, Cr 14.5 to 16.5%, Mo 15.0 to 17.0
%, Co 2.5% or less, W 3.0-4.5%, Fe 4.0
~ 7.0%, C 0.02% or less, Mn 1.0% or less, balance
Ni composition) length 100 mm, width 10 mm, thickness
Mirror-finish a 0.2 mm Hastelloy tape.
Ion beam assisted sputtering on the top surface of STEROY tape
YSZ (Y) having a thickness of 0.5 μm by the ring method_TwoO _ThreeStabilization
(Zirconia) An in-plane oriented intermediate film was used.

Next, using the CVD reactor 10 having the structure shown in FIGS.
0 ° C., the feed rate of the raw material solution was set to 0.3 ml / min, and the moving speed of the substrate in the CVD reactor 10 was 20
cm / hour, the temperature of the substrate in the reaction generation chamber 35 is set to 800
C., the pressure in the reactor 31 was set to 5 Toor, the supply amount of oxygen gas to the CVD reactor was set to 45 to 55 ccm, and the oxygen partial pressure was set to 0.45 Toor so as to be constant by the oxygen concentration measurement device, and continuous vapor deposition was performed. . The total amount of the introduced source gas was 545 to 555 ccm. Further, when performing the continuous deposition, both the main heater 95 and the auxiliary heater 90 were operated to maintain the temperature of the base material in the reaction generation chamber 35 at 800 ° C. In this way, an oxide superconducting thin film having a composition of Y ₁ Ba ₂ Cu ₃ O _7-x having a thickness of 1.0 μm was formed on the YSZ in-plane oriented intermediate film. Was obtained.

(Comparative Example 1) Next, when performing continuous vapor deposition,
Except that the auxiliary heater 90 was stopped and only the main heater 95 was operated to maintain the temperature of the base material in the reaction generation chamber 35 at 800 ° C. Similarly, an oxide superconductor of Comparative Example 1 was obtained.

The critical current density of the oxide superconductor of Example 1 was measured by a four-terminal method, and was found to be 3.0 × 10 ⁵ A /
cm ² (77 K, 0 T), which proved to have good superconducting properties. When the critical current density of the oxide superconductor of Comparative Example 1 was measured in the same manner, 1.0
× 10 ⁵ A / cm ² (77 K, 0T), indicating that the oxide superconductor of Comparative Example 1 was inferior in superconductivity to the oxide superconductor of Example 1. This is because the auxiliary heater 90 of the CVD reactor 10 was not operated during the production of the oxide superconductor of Comparative Example 1, so that a temperature distribution occurred in the longitudinal direction of the reactor 31 and the base material passed through the reaction generation chamber 35. It is presumed that when the temperature reached the vicinity of the partition wall 33 for partitioning the reaction generation chamber 35 and the base material lead-out portion 36, the temperature of the base material rose and the oxide superconducting thin film was altered.

(Example 2) The same raw material solution and a tape-shaped substrate as those used in Experimental Example 1 were prepared. Next, using the CVD reactor 110 having the structure shown in FIGS. 9 and 10, the temperature of the vaporizer of the source gas supply source was set to 230 ° C., and the supply rate of the source solution was set to 0.3 ml / min. The moving speed of the base tape in the CVD reactor 110 is 1 m / hour, the pressure in the reactor 131 is 5 Toor, and the CVD reactor 110
Continuous vapor deposition was performed with an oxygen gas supply amount of 45 to 55 ccm. The oxygen partial pressures in the CVD units A, B, and C were respectively set to 0.45 Torr, 0.50 Torr,
0.55 Toor. Also, the CVD unit A,
The temperature of the base material in each of the reaction generation chambers 135 of B and C is set to 8
The temperature was set to 00 ° C. At this time, all the main heaters 195 and the auxiliary heaters 190 were operated to maintain the base material in the respective reaction generating chambers 135 at 800 ° C. In this way, YSZ
0.6 μm thick Y ₁ Ba ₂ Cu ₃ O on the in-plane alignment intermediate film
An oxide superconducting thin film having a composition of _7-x is formed and has a length of 100
The oxide superconductor of Example 2 having a width of 10 mm and a width of 10 mm was obtained.

Example 3 Next, when performing continuous vapor deposition,
The temperature of each of the auxiliary heaters 190 is made different by the temperature control means, and the temperature of the base material of each of the reaction generating chambers 135 of the CVD units A, B, and C is set to 800 ° C. and 810, respectively.
° C and 820 ° C, except that the temperature was set to be higher as the base material progressed, in the same manner as in the case of manufacturing the oxide superconductor of Example 2 described above. Obtained.

(Comparative Example 2) Further, when performing continuous vapor deposition,
The oxide superconductor of Example 2 is manufactured except that the auxiliary heaters 190 are stopped and only the main heater 195 is operated to maintain the base material in each of the reaction generation chambers 135 at 800 ° C. In the same manner as in the case, an oxide superconductor of Comparative Example 2 was obtained.

The critical current densities of the oxide superconductors of Examples 2 and 3 were measured under the conditions of 77 K and 0 T.
9.0 × 10 ⁴ A / cm ² , 2.0 × 10 ⁵ A /
It indicates cm ^2, and showed a higher value of Example 3. When the critical current density of the oxide superconductor of Comparative Example 2 was measured in the same manner, the critical current density was 1.0 × 10 ⁴ A / cm ² (77 K, 0
T), the oxide superconductor of Comparative Example 2 showed lower values than the oxide superconductors of Examples 2 and 3.

The reason why the critical current density of Example 3 was higher than that of Example 2 is that when the oxide superconductor of Example 3 was manufactured,
It is presumed that the temperature was gradually increased as it moved through the inside of the substrate 31, so that the composition of the oxide superconducting thin film could be made uniform. The reason why the critical current density of Comparative Example 2 was lower than that of Examples 2 and 3 is that the auxiliary heaters 190 of the CVD reactor 110 were not operated during the production of Comparative Example 2, so that the temperature in the longitudinal direction of the reactor 131 was low. When the distribution is generated and the base material reaches the vicinity of the partition walls 137 and 133 that partition the reaction generation chamber 135 and the boundary chamber 138 or the base material outlet 136 through the reaction generation chamber, the temperature of the base material is increased. It is presumed that the oxide superconducting thin film was altered due to the rise.

[0079]

The CVD reactor of the present invention is provided with a cylindrical main heater for heating the entire reactor and an auxiliary heater for heating only the reaction generation chamber of the reactor, and is provided to the reaction generation chamber. Since the amount of heat is larger than the amount of heat given to the base material introduction part and the base material discharge part, even if the raw material gas is introduced into the reaction generation chamber, the temperature of the atmosphere in the reaction generation chamber does not decrease and the inside of the reactor is reduced. Temperature distribution is kept constant, so that the temperature of the base material does not rise even when the base material passes through the reaction generation chamber and reaches the vicinity of the partition wall, and the superconductivity of the oxide superconductor is reduced. Can be prevented.

In the CVD reactor of the present invention, a plurality of reaction generating chambers are provided in series in the reactor in the direction of travel of the base material, so that a plurality of CVD reactions can be performed continuously.
Compared with the case where only one reaction generation chamber is manufactured, it is possible to improve the formation rate of the thin film and the thickness of the formed thin film. Further, the reactor is provided with a main heater that heats the entire reactor and an auxiliary heater that separately heats each reaction generation chamber, and the amount of heat given to each reaction generation chamber is controlled by a base material introduction section and a boundary chamber. And the amount of heat given to the base material outlet, so that even if the source gas is introduced into each reaction generation chamber, the temperature of the atmosphere in each reaction generation chamber does not decrease and the temperature distribution inside the reactor is reduced. Since the substrate is kept constant, the temperature of the substrate does not increase even when the substrate reaches the vicinity of the partition wall after passing through the reaction generation chamber, so that the characteristics of the oxide superconductor can be prevented from deteriorating.

Further, in the CVD reactor of the present invention, each auxiliary heater is independently controlled by the temperature control means, so that the temperature of the base material in each reaction generation chamber can be controlled independently. Since the temperature of the base material in each reaction generation chamber can be arbitrarily changed and the conditions of the CVD reaction in each reaction generation chamber can be made different, for example, an oxide superconducting thin film is formed on the base material to oxidize. When trying to obtain a superconductor, an oxide superconducting thin film can be formed under optimal conditions in each reaction generation chamber,
Since an oxide superconducting thin film having a uniform composition can be obtained, the superconducting properties of the oxide superconductor can be further improved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a CVD reactor according to a first embodiment of the present invention.

FIG. 2 is a front view showing a CVD reactor according to the first embodiment of the present invention.

FIG. 3 is a front sectional view showing a detailed structure of a reactor of the CVD reactor according to the first embodiment of the present invention.

FIG. 4 is a plan sectional view showing a detailed structure of a reactor of the CVD reactor according to the first embodiment of the present invention.

FIG. 5 is a configuration diagram of a side heater constituting an auxiliary heater of the CVD reactor according to the first embodiment of the present invention.

FIG. 6 is a configuration diagram of an upper heater constituting a main heater of the CVD reactor according to the first embodiment of the present invention.

FIG. 7 is a configuration diagram of a lower heater constituting a main heater of the CVD reactor according to the first embodiment of the present invention.

FIG. 8 is a graph showing a temperature distribution in a reactor of the CVD reactor according to the first embodiment of the present invention.

FIG. 9 is an exploded perspective view showing a CVD reactor according to a second embodiment of the present invention.

FIG. 10 is a front view showing a CVD reactor according to a second embodiment of the present invention.

FIG. 11 is a front sectional view showing a detailed structure of a reactor of a CVD reactor according to a second embodiment of the present invention.

FIG. 12 is a plan sectional view showing a detailed structure of a reactor of a CVD reactor according to a second embodiment of the present invention.

FIG. 13 is a graph showing a temperature distribution in a reactor of the CVD reactor according to the second embodiment of the present invention.

FIG. 14 is a view showing a conventional CVD reactor,
(A) is a front view, (b) is a side view.

FIG. 15 is a graph showing a temperature distribution in a reactor of a conventional CVD reactor.

FIG. 16 is a graph showing a temperature distribution in a reactor of a conventional CVD reactor.

[Explanation of symbols]

 10, 110 CVD reactor 31, 131 Reactor 32, 33, 132, 133, 137 Partition wall 34, 134 Substrate introduction section 35, 135 Reaction generation chamber 36, 136 Substrate exit section 138 Boundary chamber 38 Substrate 40, 140 Gas Diffusion unit 45, 145 Gas diffusion member 70a, 170a Gas exhaust hole 70b, 170b Exhaust pipe 70c, 170c Exhaust port 90, 190 Auxiliary heater 95, 195 Main heater 183 Temperature control means R Substrate transport area

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Nobuyuki Sadakata 1-5-1 Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd. (72) Inventor Takashi Saito 1-1-5-1 Kiba, Koto-ku, Tokyo Stock Inside Fujikura (72) Inventor Shigeo Nagaya 20-1, Kitakanyama, Odaka-cho, Midori-ku, Nagoya-shi, Aichi F-term in the Electric Power Research Laboratory, Chubu Electric Power Co., Inc. 4K030 AA11 BA01 BA42 CA02 CA17 EA04 EA11 FA10 GA14 HA04 KA08 KA23 LA03 5G321 AA01 AA02 AA04 AA05 AA07 CA18 CA21 CA24 CA27 CA28 DB40

Claims (4)

[Claims] A reactor for performing a CVD reaction for depositing a thin film by chemically reacting a source gas on the surface of a moving tape-shaped substrate; a gas diffusion unit for supplying the source gas to the reactor; And a gas exhaust port connected to an exhaust port for exhausting the gas. The reactor is provided with a base material introduction part, a reaction generation chamber, and a base material discharge part which are defined by partition walls. A main heater that covers the reactor and heats the entire reactor; and an auxiliary that is provided inside the main heater and covers the entire reaction generation chamber partitioned by the partition and heats the reaction generation chamber. A CVD reactor, comprising: a heater. 2. A reactor for performing a CVD reaction for depositing a thin film by chemically reacting a raw material gas on the surface of a moving tape-shaped base material, a gas diffusion unit for supplying the raw material gas to the reactor, and an inside of the reactor. And a gas exhaust port connected to an exhaust port for exhausting the gas. The reactor is provided with a base material introduction part, a reaction generation chamber, and a base material discharge part which are defined by partition walls. A plurality of the reaction generation chambers are provided in series in the moving direction of the tape-shaped substrate, a boundary chamber is provided between the reaction generation chambers, and the substrate introduction portion inside the reactor. A base material transport region that passes through the reaction generation chamber, the boundary chamber, and the base material outlet is formed, and the gas diffusion unit is provided for each of the reaction generation chambers, and covers the reactor to cover the entire reactor. Heating main heat And a plurality of auxiliary heaters provided inside the main heater and heating the respective reaction generation chambers partitioned by the partition walls, respectively. 3. The CVD reactor according to claim 2, further comprising temperature control means capable of independently controlling the temperature of each of said auxiliary heaters. 4. A method for producing an oxide superconductor using the CVD reactor according to claim 1, wherein the temperature inside the reaction generation chamber is reduced by introduction of a raw material gas. In addition, while controlling the auxiliary heater so that the temperature inside the reaction generation chamber is equal to the temperature near the partition partitioning the reaction generation chamber, the tape-shaped base material is chemically reacted with a source gas to form an oxide. A method for producing an oxide superconductor, comprising depositing a superconducting thin film.