JPH0259404A - Device for producing superconductor - Google Patents

Abstract

PURPOSE:To efficiently form a layered superconductor thin film on a substrate by connecting plural high-vacuum chambers in series, supplying a raw gas contg. one kind of element among different elements into each chamber, and simultaneously passing the substrate through each chamber. CONSTITUTION:Plural high-vacuum chambers 13 are connected with one another in series, and raw material supply means 20a, 20b, 20c, and 20d are connected to the respective chambers 13. The raw gas contg. one kind among the elements constituting a superconductor thin film is separately supplied to each chamber 13 respectively from the supply means 20a, 20b, 20c, and 20d. The substrate is simultaneously passed through each chamber 13 to successively deposit the elements supplied from the supply means 20a, 20b, 20c, and 20d on the substrate, and a layered superconductor thin film is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for forming a superconductor thin film made of a desired element by a CVD method.

[Prior art and problems to be solved by the invention] One of the vapor phase epitaxial methods for manufacturing thin films is the CVD method (Che
vapor deposition).

The CVD method is a method in which a desired thin film is formed on a substrate by chemically reacting raw material gas containing elements constituting the thin film.

In recent years, research has been conducted into techniques for producing superconductors using the CVD method. According to this research, compound gas (raw material gas) containing elements constituting a superconductor is supplied into a reaction chamber to cause a chemical reaction, and the reaction products are deposited on a substrate to form a thin film. The aim is to obtain a superconductor thin film by annealing the .

In order to obtain superconductivity, it is necessary to control the composition of the thin film with high precision, so when manufacturing superconductors using the CVD method, it is necessary to control the vapor pressure of each element in the raw material gas with high precision. . For this reason, in conventional CVD equipment,
It is conceivable to supply raw material gases of each element at predetermined vapor pressures to the reaction chamber through separate routes, and to cause a chemical reaction in a state where these raw material gases are mixed.

However, due to circumstances such as the temperature at which a given vapor pressure is obtained differs for each element, even if the raw material gases for each element are supplied separately to the reaction chamber, the temperature conditions will collapse due to the mixing of these gases, and at that point The desired vapor pressure cannot be achieved due to precipitation of raw material compounds, making it difficult to obtain the desired superconductor.

Furthermore, as a result of recent research, it has been found that superconductors exhibiting excellent superconductivity have a layered structure with different constituent elements.

However, in the above-mentioned CVD apparatus, since the raw material gases of each element are reacted in a mixed state,
It is difficult to obtain a superconductor with such a layered structure.

The present invention was made in view of the above-mentioned conventional circumstances, and
The purpose of the present invention is to provide an apparatus for manufacturing a desired superconductor thin film by a method.

[Means for Solving the Problems] A superconductor manufacturing apparatus according to the present invention that achieves the above object includes a plurality of raw material supply means and a plurality of raw material supply means connected to each raw material supply means and connected to each other in series. a chamber;
each source supply means separately supplies a source gas containing one of the elements constituting the superconductor thin film into the chamber, and each chamber accommodates a substrate on which the superconductor thin film is deposited. The method is characterized in that the elements supplied from each raw material supply means are deposited on the base material.

[Effects] Each raw material supply means supplies one of the elements that compose the superconductor thin film.
Raw material gases containing different types of raw material gases are separately supplied into the chambers, each chamber housing a base material on which a superconductor thin film is to be deposited, and elements supplied from each raw material supply means are deposited on the base material.

Therefore, by sequentially moving the base material from chamber to chamber, a superconductor thin film having a predetermined composition and a structure in which different types of raw material elements are deposited in layers can be obtained.

[Effects] According to the superconductor manufacturing apparatus of the present invention, each constituent element is deposited on the base material by supplying various raw material gases separately, making it easy to manage the vapor pressure of each constituent element. Therefore, composition control of the superconductor becomes extremely easy, and a superconductor thin film having a desired composition can be easily obtained.

In addition to the above-mentioned effects, it is possible to obtain a superconductor thin film having a structure in which constituent elements are deposited in layers, and excellent superconductivity can be obtained.

[Example code] The present invention will be specifically explained based on examples.

1 and 2 show a manufacturing apparatus according to an embodiment of the present invention.

As illustrated, a carrier gas supply pipe 3 is connected to one end of the supply pipe 1, and this carrier gas supply pipe 3 is connected to a carrier gas supply source (not shown). Further, a heater 5 is provided at one end of the supply pipe 1, and a raw material gas supply pipe 7 from a raw material gas supply source (not shown) is connected to the portion of the supply pipe 1 where the heater 5 is provided. There is.

On the other hand, the other end of the supply pipe 1 is provided with a medium vacuum chamber 11 and a high vacuum chamber 13 connected in series.

The medium vacuum chamber 11 and the high vacuum chamber 13 are each connected to a vacuum source (not shown), and the internal pressure of the supply pipe 1 is 760°C.
~10 torr, whereas the medium vacuum chamber 11
The internal pressure is 10-1 to 1O-3t.

The pressure is reduced to about rr, and the internal pressure of the high vacuum chamber 13 is 1O.
The pressure is reduced to about -5 torr. Additionally, heaters 1 are provided in the medium vacuum chamber 11 and the high vacuum chamber 13, respectively.
2.14 are provided and these chambers 11.13
The inside can be heated to a predetermined temperature.

Partitions 15 and 17 having nozzles 15a and 17a are provided between the supply pipe 1 and the medium vacuum chamber 11 and between the medium vacuum chamber 11 and the high vacuum chamber 13, respectively. The chamber 11 is the nozzle 15a.
The medium vacuum chamber 11 and the high vacuum chamber 13 communicate through the nozzle 17a.

The supply pipe 1, carrier gas supply pipe 3, heater 5, raw material gas supply pipe 7, medium vacuum chamber 11, heater 12, and partitions 15 and 17 constitute a raw material supply means. B 1-
In this example for producing a 3r-Ca-Cu based superconductor, there are 20a for supplying a raw material gas containing Bi, 20b for supplying a raw material gas containing Sr, and 20 for supplying a raw material gas containing Ca.
One raw material supplying means of the same structure is provided as each of the raw material gas supplying means 20d containing c and Cu, that is, there are four in total in the apparatus.

Furthermore, the high vacuum chamber 13 connected to the medium vacuum chamber 11 also has its own raw material supply means 20a, 20b, 20c.
, 20d, and these high vacuum chambers 13 are arranged in series from the raw material supply means 20a to 20d, and adjacent ones are connected to each other.

Gate valves 23 are provided between the high vacuum chambers 130 connected to each other, and by operating these gate valves 23, the high vacuum chambers 13 can be brought into communication or airtightly isolated.

In addition, a high vacuum chamber 1 connected to the raw material supply means 20d
3 is connected to the pretreatment chamber 2 via a gate valve 25.
7 is connected, and by operating the gate valve 25, the high vacuum chamber 13 and the pretreatment chamber 25 can be brought into communication or airtightly isolated. This pretreatment chamber 27 performs pretreatment for depositing the superconductor raw material on the base material 30. In addition to this pretreatment means, the base material 30 is placed in a high vacuum between the raw material supply means 20d and 20a. Means for feeding the chamber 13 is also provided. Note that a pretreatment chamber 27 is provided in each high vacuum chamber 13.
A susceptor 33 is provided to support the base material fed from the side.

Also, a high vacuum chamber 1 connected to the raw material supply means 20a
3 is connected to an annealing vacuum furnace 37 via a gate valve 35.
are connected to each other, and by operating the gate valve 35, the high vacuum chamber 13 and the annealing vacuum furnace 37 can be brought into communication or airtightly isolated. This annealing vacuum furnace 37 heats the thin film deposited on the base material 30 in an oxygen atmosphere to impart 02 to the thin film, and by this annealing, the thin film has a composition of a superconductor.

B1-5r-
An example of forming a Ca-Cu-0 based superconductor thin film will be described.

In order to increase the deposition rate of the superconductor thin film, B i (OC2H3) 3.5r(HFA)2, C
Using metal complex gases of a(HFA)2 and Cu(HFA)2, 1 of each of these metal complex gases is supplied from the raw material supply means.
Each type is supplied with surplus ligands. Further, Ar gas is used as a carrier gas.

In preparation for starting the production of the superconductor, each medium vacuum chamber 11 and high vacuum chamber 13 is reduced to a predetermined pressure, and each heater 5, 12, 14 is activated to bring it into a heating state. Here, since the medium vacuum chamber 11 is interposed between the supply pipe 1 and the high vacuum chamber 13 without reducing the pressure all at once, the burden on the vacuum pump is reduced and a considerably high vacuum can be easily obtained. Can be done.

First, the base material 30 is pretreated in the pretreatment chamber 27, and the base material 30 is fed to the high vacuum chamber 13 connected to the raw material supply means 20d and supported by the susceptor 33. When the base material 30 is located in the high vacuum chamber 13 connected to the raw material supply means 20d, the gate valves 23.25 are closed and the high vacuum chamber 13 is closed.
is isolated from the other chambers 13.27. Then, Cu (HFA) 2 gas is supplied to the supply pipe 1 from the raw material supply source connected to the raw material supply means 20d via the raw material supply pipe 7, and this raw material gas is communicated with the high vacuum chamber 13 through the nozzles 15a and 17a. Cu molecules, which are the superconductor raw material produced by thermal decomposition of the primary gas, are deposited. In addition, when introducing this raw material gas into the high vacuum chamber 13, the supply pipe 1, the medium vacuum chamber 11, the high vacuum chamber 13
Since the pressure is reduced in stages, Cu molecules are appropriately accelerated and deposited on the base material 30 by collision due to the effect of differential pumping, thereby forming a dense thin film.

Next, the gate valve 23 is opened to feed the base material 30 on which the Cu element has been deposited to the high vacuum chamber 13 connected to the raw material supply means 20c and supported by the susceptor 33, and the gate valve 23 is closed to feed the base material 30 on which the Cu element has been deposited into the high vacuum chamber 13 connected to the raw material supply means 20c. 13 is isolated from other chambers 13. Then, Ca is supplied from the raw material supply source connected to the raw material supply means 20c via the raw material supply pipe 7 to the supply pipe
(HFA)2 gas is supplied, and similarly to the above process, this raw material gas is introduced into the high vacuum chamber 13 communicated through the nozzles 15a and 17a, and the superconductor raw material is produced by thermal decomposition of the raw material gas. Ca molecules are deposited on the base material 30 on which Cu molecules have already been deposited.

Next, the gate valve 23 is opened and the base material 30 on which Cu and Ca elements are deposited in layers is fed to the high vacuum chamber 13 connected to the raw material supply means 20b and supported on the susceptor 33, and the gate valve 23 is closed. This high vacuum chamber 13
is isolated from other chambers 13. Then, 5r (HFA)2 gas is supplied to the supply pipe 1 from the raw material supply source connected to the raw material supply means 20b via the raw material supply pipe 7, and similarly to the above process, this raw material gas is communicated through the nozzles 15a and 17a. Sr molecules, which are the superconductor raw material produced by thermal decomposition of the raw material gas, are deposited on the base material 30 on which Cu and Ca molecules have already been deposited.

Next, the gate valve 23 is opened and CuS Ca and S
The base material 3o on which the r element is deposited in a layered manner is supplied to the raw material supply means 20a.
The susceptor 33 is supplied to the high vacuum chamber 13 connected to the
The high vacuum chamber 13 is isolated from other chambers 13.37 by closing the gate valve 23. Then, B i (OC2H5) 3 is supplied to the supply pipe 1 from the raw material supply source connected to the raw material supply means 20a via the raw material supply pipe 7.
A high vacuum chamber 1 is supplied with gas and communicated with this raw material gas through the nozzles 15a and 17a in the same way as in the above process.
Bi molecules, which are the superconductor raw material produced by thermal decomposition of the raw material gas, are deposited on the base material 3o on which Cu, Ca, and Sr molecules have already been deposited.

As mentioned above, superconductor raw materials Cu, Ca, Sr, B
The base material 3o on which i has been deposited in a layered manner is sent to the vacuum furnace 37 by opening the gate valve 35, and oxygen is added to form a thin film on the base material 30 to form a B i -5r-Ca-Cu-0 based superconductor. Body.

In the above series of steps, each raw material gas is supplied separately and the generation of superconducting raw material from the raw material gas is performed separately for each raw material gas, so the raw material gas is not affected by other raw material gases. The appropriate temperature and vapor pressure can be easily maintained, and a superconductor with the expected composition can be easily obtained.

Incidentally, as is easily understood from the above embodiments, the number of raw material supply means is appropriately set according to the number of elements constituting the superconductor.

In addition, a long ribbon-like material is used as the base material for forming the superconductor, and a plurality of chambers (high vacuum chamber 13 in the above embodiment) connected to each raw material supply means and accommodating the base material are always connected. It is also possible to continuously form a long superconductor by moving this ribbon material in its longitudinal direction while in a communicating state (in the above embodiment, the gate valve is open).

[Brief explanation of the drawing]

Fig. 1 is a plan view showing one embodiment of the present invention, and Fig. 2 is a plan view showing an embodiment of the present invention.
It is a sectional view taken along the line ■-■ in the figure. 7 is a raw material gas supply pipe; 13 is a high vacuum chamber; 20a, 20b, 20c, and 20d are raw material supply means; 30 is a base material.

Claims (1)

[Claims] Comprising a plurality of raw material supply means and a plurality of chambers connected to each raw material supply means and connected to each other in series, each raw material supply means containing one type of elements constituting the superconductor thin film. A superconductor characterized in that raw material gases are separately supplied into chambers, each chamber accommodates a base material on which a superconductor thin film is deposited, and elements supplied from each raw material supply means are deposited on the base material. Conductor manufacturing equipment.