JPH03153597A - Device for vaporizing cvd raw material for production of oxide superconductor - Google Patents

Abstract

PURPOSE:To form an oxide superconductor film having a uniform compsn. free from unequalness on a substrate by connecting plural vaporizing cylinders for generating gaseous raw materials to a manifold and connecting the vaporizing cylinders disposed at upper and lower parts vertically along a perpendicular plane to the manifold. CONSTITUTION:A carrier gas is sent from respective supply holes 14 into the respective vaporizing cylinders 10, 11, 12 and gaseous oxygen is sent from a 1st introducing pipe 17 and a 2nd introducing pipe 20 into a mixing pipe 16. The respective vaporizing cylinders 10, 11, 12 are heated near to the vaporizing temp. of the respective gaseous source compds. The gaseous raw materials entering the mixing pipe 16 are sufficiently agitated and mixed by the gaseous flow of the gaseous oxygen sent from the 1st introducing pipe 17 and the gaseous flow of the gaseous oxygen sent from the 2nd introducing pipe 20. The mixture arrives at a reactor 18. The gaseous mixture composed of the gaseous raw materials and the gaseous oxygen arriving at the reactor 18 is heated in the reactor 18 and reacts with the gaseous O2 in the atmosphere, by which the respective oxides of Y and Ba and Cu and formed as the film with the uniform compsn. Reaction is generated in the respective elements by the high-temp. state at the time of the film formation and the film of the oxide super conductor consisting of the Y-Ba-Cu-O system is formed.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a method for producing an oxide superconductor film by a CVD method using a metal complex as the 1Q family, and the invention relates to a method for making a film of an oxide superconductor by a CVD method using a metal complex as a 1Q family, and in which the material gas is made uniform and the film quality is made uniform. It has improved.

``Conventional technology J: Chemical vapor deposition (CVD) is known as a method that has a faster deposition rate than thin film formation methods such as sputtering and MBE, and can form thicker films in a single time. .

FIG. 2 shows an example of an apparatus used in this CVD method.

The device of this example is equipped with a plurality of bubblers 1 containing solid raw materials of elements constituting an oxide superconductor.
A supply pipe 3 incorporating a mass flow controller 2 is connected to each bubbler I, and the supply pipe 3 is connected to a carrier gas supply source such as Ar gas, and each bubbler 1 is connected to a reactor 6 via a discharge pipe 5. has been configured. In addition, in FIG. 1, the reference numeral 7 indicates an air valve.

The reactor 6 is a container-shaped container whose internal atmosphere can be adjusted, and is equipped with a substrate holder and a heater. can be deposited in the

``Problem to be Solved by the Invention J When attempting to manufacture an oxide superconductor using the apparatus shown in Figure 2, since the constituent raw materials of the oxide superconductor are solid at room temperature, they are heated in a vaporization tube l. In the case where the raw material gas is generated by vaporization (U), the raw material gas recrystallizes in the middle of the discharge pipe 5 and causes clogging, or in the case where no clogging occurs. There is a problem that the mixture is not uniformly mixed in the reaction section of the Tera reactor 6. If uniform mixing is not possible in this way, the resulting oxide superconductor film may have unevenness in the component elements, resulting in a non-uniform film. There is a problem in that it is difficult to obtain and cannot stably produce oxide superconductors with high critical current density.

The present invention has been made to solve the problems listed in q.
This vaporization device eliminates the possibility of clogging of the piping system before the raw material gas reaches the actor, and forms an oxide superconductor film with a uniform composition on the substrate without any unevenness. For the purpose of providing.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides an oxide superconductor on a substrate by chemical vapor deposition using a compound of each element constituting the oxide superconductor. In the generation device, a plurality of reaction sections containing compounds of each element are individually arranged vertically, and the gas exhaust holes of each reaction section are arranged vertically in parallel along the same vertical plane. In addition to being connected to the side wall of the collecting pipe, a mixing pipe is connected to the bottom of the collecting pipe, this mixing pipe is connected to a reactor, and an oxygen gas supply pipe is connected to the mixing pipe.

"Function" Since multiple vaporization cylinders that generate raw material gas are connected to the collecting pipe, in addition to mixing the raw material gases in the collecting pipe, oxygen gas is also allowed to flow into the mixing pipe connected to the collecting pipe. Since the raw material gas is stirred and mixed at the same time, the sufficiently mixed raw material gas is sent to the actor. In addition, since the vaporization cylinders arranged vertically above and below are connected to the collecting pipe, there is no unevenness in the raw material gas in the left and right direction when facing forward in the direction of gas flow, and the inside of the reactor is An oxide superconductor film with uniform composition is formed on the base (O).

"Embodiment" FIG. 1 shows an embodiment of the present invention, and the reference numeral 1 in the figure shows an embodiment of the present invention.
0.11.12 indicates a vaporization cylinder for vaporizing the raw material. These vaporizer cylinders 10, 11 and 12 are arranged horizontally and in parallel, vertically aligned. These vaporizer cylinders 10. A container-shaped storage section I3 is provided inside If, +2, and the storage section 13... contains raw material GI for producing an oxide superconductor.

Gv and Gj are stored.

The raw materials G,,G,,G are compounds of elements constituting the oxide superconductor, and are Y-Ba-C
When producing a u-O based oxide superconductor, a gaseous source of Cu as the raw material GI, a gaseous source of Y as the raw material G, and a gaseous source of Y as the raw material G.
, a Ba gas phase source is used. More specifically, powders of acetylacetone compounds, noketone compounds such as hexafluoroacetylacetone compounds, and cyclopentagenyl compounds of each of the above-mentioned elements are used as the gas phase source. In addition, as a Ba source, Ba-bis-2,2,6,6
Tetramethyl-3,5-hebutandionate “abbreviation B
a(D P M') tJ, Ba-bis 1.1, 1.2
．． 2-Pentafluoro-6,6-dimethyl-3,5 heptanedione "Abbreviation: Ba(PPM)yJ, Ba-
Bis-11,1,5,5,5-hexafluoro-2,4
-pentanedione [abbreviation Ba (HFA) tJ etc. β-
Diketone chelate complexes and the like are used. In the apparatus of this embodiment, a Cu complex is stored in the vaporization tube 10, a Y complex is stored in the vaporization tube 11, and a Ba complex is stored in the vaporization tube 12.
It houses a complex of

Also, the vaporizer cylinder 10. Carrier gas supply holes 14 are formed at the end sides of If and 12, respectively, and each vaporization cylinder 10. The other ends 10a, 11a, and 12a of II and +2 are vertical collecting pipes arranged vertically! Connected to the side of 5,
The joint portion of each vaporizing cylinder 10, 11, 12 with the collecting pipe 15 is formed to be slightly narrowed. In addition, each vaporizer cylinder 1
As the carrier gas introduced into the carrier gas, an inert gas such as Ar gas or a mixture of an inert gas and O gas is preferably used.

On the other hand, the bottom of the collecting pipe I5 is connected to the horizontally arranged mixing pipe 1.
6, and one end of the mixing tube 16 is connected to the first oxygen gas introduction 1FI7, and the mixing tube 1
A beam actor 18 is connected to the other end of 6. Furthermore,
In the mixing pipe 16, a second oxygen gas introduction pipe 20 is connected between the joint part to the collecting pipe I5 and the joint part to the actor 18. Note that the first introduction pipe 17
A detection tube 21 connected to a pressure gauge is connected to.

The reactor I8 includes an airtight container 23 that can house a substrate (base material) 22 therein, and a heating device 24 installed on the outer periphery of this airtight container 23, and the airtight container 23 is connected to a vacuum evacuation device. .

Next, a case will be described in which an oxide superconductor film is formed on the substrate 22'' using the CVD apparatus having the above configuration.

First, the substrate 22 is set inside the reactor I8, and the inside of the reactor 18 is started to be exhausted, and the heating device 2
4 to heat the inside of the reactor 18. Next, each carburetor 1
0, 11, and 12, the carrier gas is sent from each supply hole 14, and the first introduction pipe is inside the mixing pipe 16!
7 and the second introduction pipe 20, each vaporization [10
, 11, and 12 are heated to around the vaporization temperature of each gas phase source compound.

Through the above operations, a part of each gas phase source compound is vaporized, and the gas of the vaporized compound (raw material gas) is discharged from each vaporization cylinder 10, 11, 12 to the collecting pipe 15 along with the carrier gas. The mixing tube 16 is mixed while descending.
leading to. When the raw material gas discharged into the mixing tube 16 is mixed with the oxygen gas sent from the first introduction tube 17, six oxygen gases are supplied from the second introduction tube 20 before reaching the reactor 18. This leads to reactor I8. Here, the raw material gas that has entered the mixing tube 16 is sufficiently stirred and mixed by the oxygen gas airflow sent from the first introduction tube 17 and the oxygen gas airflow sent from the second introduction tube 20, and reaches the reactor 18.

The mixed gas of raw material gas and oxygen gas that has reached the reactor 18 is heated inside the reactor 18 for a minute of M? However, by reacting with O and gas in the atmosphere, a film of Y, Ba, and Cu hexoxides is formed with a uniform composition, and each element reacts with the high temperature conditions during film formation, forming a Yr3a-Cu-0 system. A film of oxide superconductor is formed.

By the way, since the raw material gases generated from the surface vaporizers 10, 11, and 12 and sent to the collecting pipe 15 have a high specific gravity, it is possible that they are not mixed uniformly. In this respect, in the apparatus having the above configuration, the mixing tube I
Oxygen gas is introduced into the reactor 18 from the first inlet pipe I7 and the second inlet pipe 20 and sent to the reactor 18 while being stirred, so that each raw material gas is sufficiently stirred and mixed. In addition, the carburetor 10,
Since no valve is provided between 11 and 12, the collecting pipe 15, and the mixing pipe 16, there is no possibility that the raw material gas will become clogged on the way. Furthermore, since the vaporizer fml 0.11.12 is arranged horizontally and in the air along the same vertical plane, the ingredients of the raw material gas flowing on the left hand side facing forward in the flow direction of the raw material gas and the right hand side. There is an effect that the components of the flowing raw material gas do not differ, and that no component unevenness occurs in the films formed on the left and right sides of the substrate 22.

As explained above, according to the apparatus having the above structure, it is possible to send the raw material gas in a sufficiently mixed state to the reactor 18, so that the oxide superconductor film has a uniform composition and does not have any local unevenness. can be manufactured.

In this example, the substrate 22 was provided as a base material provided inside the reactor I8, but instead of the substrate 22, a tape-shaped base material, its feeding device, and a winding device were provided. Of course, it is possible to manufacture a tape-shaped oxide superconductor by depositing it on the upper surface of the reactor I8 while moving it inside the reactor I8.

“Manufacturing Example” Y-B a-CuO
A film of the oxide superconductor system was fabricated.

A Cu acetylacetone compound was used as the Cu source, a cyclopentagenyl compound of Y was used as the Y source, B a (D P M )z was used as the Ba source, and Ar gas was used as the carrier gas.

The temperature of the vaporization cylinder containing the Cu source was heated to 180°C, the temperature of the vaporization cylinder containing the Y source was heated to 180°C, and the temperature of the vaporization cylinder containing the Ba source was heated to 230°C. Raw material gas was generated. In addition, oxygen gas was introduced into the mixing tube from the first introduction tube at a rate of 300 ffic/min, and at the same time, oxygen gas was introduced into the mixing tube from the second introduction tube at a rate of 20-7 ffic/min.
Oxygen gas was allowed to flow in at a rate of 1.5 min. In addition, the inside of the reactor was evacuated and heated to 850°C to
A film was formed on the substrate manufactured by Ioj.

The obtained H film of the Y-B a-Cu-0 based oxide superconductor was heated to a critical temperature of 91 and an IM field current density of 10'A/c.
The critical temperature and critical current density were measured at multiple parts surrounding the center of the substrate, and the measurement results at all the parts showed the same characteristics as above.

Therefore, it has been found that by using the CVD process having the above structure, it is possible to produce an oxide superconductor film exhibiting partially uniform superconducting properties.

"Effects of the Invention" As explained above, the present invention collects the raw material gas generated from each vaporization surface into a collecting pipe, then sends it to a mixing pipe, and sends oxygen gas to this mixing pipe from an introduction pipe and sends it to a reactor. Since the raw material gases are sufficiently stirred and mixed by introducing oxygen gas into the mixing tube, the uniformly mixed raw material gases can be sent to the reactor. Therefore, in the reactor, the superconducting properties are uniform in some parts.
A stable oxide superconductor film can be formed.

In addition, since the vaporization cylinders are arranged vertically and connected to the collecting pipe for mixing, the non-uniformity of the gas on the left and right sides when facing the ml side of the gas flow direction is eliminated, and the base inside the reactor is An oxide superconductor film with uniform characteristics in the left-right direction can be obtained on the material.

Because of the above, the raw material gas sent to the actor can be made uniform, so that a homogeneous film with a high critical current density can be obtained, and a large capacity of film formation can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of an example of a conventional device. + 0.11.12... Vaporizer tube, I4... Introductory hole, 1
5... Collecting pipe, 16... Mixing pipe, 17... First introduction pipe, 18... Reactor, 20... Second introduction pipe, 2
2... Substrate (base material), 24... Heating device. Figure 1 10r+

Claims (1)

[Claims] In a device that generates an oxide superconductor on a substrate by chemical vapor deposition inside a reactor using compounds of each element that makes up the oxide superconductor, multiple reaction tubes containing compounds of each element are lined up one above the other. The gas discharge holes of each reaction tube are arranged vertically in parallel along the same vertical plane and connected to the side wall of a vertical collecting pipe, and a mixing pipe is connected to the bottom of the collecting pipe. A CVD raw material vaporization apparatus for producing an oxide superconductor, characterized in that the mixing tube is connected to a reactor, and the mixing tube is connected to an oxygen gas introduction tube.