JPH01166415A - Manufacture of superconductive film - Google Patents

Abstract

PURPOSE:To increase the satulation current density (Jc) by radiating a high voltage of pulse ion beams instantly to a target substrate which consists of a superconductive material to generate a spatter gas, and forming a superconductive film on the surface of the substrate with membrane. CONSTITUTION:By applying a high voltage pulse of a reformed wave form to an ion beam generator 2, a high voltage pulse ion beams 7 are generated instantly from the generator 2. The high voltage pulse ion beams 7 are radiated to a target substrate 4 which consists of a superconductive material in a vacuum ambiance. The pulse ion beams 7 make the surface of the target substrate 4 into plasma instantly and in a nonthermal equilibilium, and generate a highly active spatter gas 5. The resultant spatter gas 5 is pulsatively implanted into the surface of the substrate with film, and a superconductive membrane of an extensively strong orienting property and a large membranous thickness can be produced. In such a way, the satulation current density (Jc) can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a superconducting film, and particularly to a method for manufacturing a superconducting film using a high-pressure pulsed ion beam.

[Prior Art] Superconducting materials have attracted attention in recent years, and are used in three main fields: generation of ferromagnetism, transport of large currents, and devices. Then, this superconducting material is used as a film, for example, Cu'l
A method for manufacturing a superconducting film formed on the surface of a film-forming substrate such as oO, 5rTi03, etc. has been developed.

Conventionally, methods for producing superconducting films include (1) mixing and sintering superconducting material powder on the surface of a film-forming substrate, or sintering after coprecipitation, and C) continuously applying a relatively low voltage of several tens of volts. There have been methods such as irradiating an ion beam onto a target substrate made of a superconducting material to generate sputtering gas to form a film on the surface of the substrate, and (3) plasma spraying on the surface of a film forming substrate made of a fl conductive material.

[Problems to be Solved by the Invention] By the way, none of the conventional methods for producing superconducting films have been able to obtain a superconductor having a single crystal or a strong writing tendency close to a single crystal, and the film thickness There was also the problem that it was thin.

Therefore, there was a problem that the saturation current density (Jc)^/32 of the superconducting film was small and the total amount of current could not be large.

In view of the above-mentioned problems, the present invention provides a saturation current density (J
c) It is an object of the present invention to provide a method for manufacturing a superconducting film having a single crystal structure or a strong write orientation close to this structure and having a thick film thickness in order to increase the value of c).

[Means for Solving the Problems] In order to solve the problems in the prior art, the present invention applies a waveform-shaped high voltage pulse to an ion beam generator,
This generator instantaneously generates a high-pressure pulsed ion beam and irradiates it onto a target substrate made of superconducting material in a vacuum atmosphere to generate sputtering gas and form a superconducting film on the surface of the film-forming substrate. be.

[Function] By applying a waveform-shaped high voltage pulse to the ion beam generator configured as described above, a high voltage pulsed ion beam is instantaneously generated from the generator. A target substrate made of a superconducting material is irradiated with this high-pressure pulsed ion beam in a vacuum atmosphere. The pulsed ion beam instantaneously turns the surface of the target substrate into plasma in a non-thermal equilibrium manner, generating highly active sputtering gas.

The sputtering gas here is pulsed onto the surface of the film-forming substrate, producing a superconducting film with extremely strong orientation.

[Example] The method for manufacturing a superconducting film of the present invention will be described in detail below with reference to the accompanying drawings.

First, an example of an apparatus employed to carry out the method of the present invention will be described. As shown in FIG. 1, an ion beam generator 2 is installed facing inside a closed container 1. These closed container 1 and ion beam generator 2 are connected to an exhaust system (not shown), and the insides of each are maintained in a vacuum atmosphere. The above ion beam generator r! 1
2 consists of an ion source and an electrostatic accelerator that flashover the solid surface using high voltage, supply plasma, and instantaneously generate a large amount of ions.

A high-voltage pulse power source 3 for an ion source is connected to this ion beam generator 2 . The high-voltage pulse power supply 3 for the ion source includes, for example, a Marx high-voltage generator that generates high-voltage pulses, and a Blumlein waveform shaping circuit that shapes the waveform of this high-voltage pulse. A target substrate 4 made of a superconducting material is provided in the sealed container 1 and inclined so as to face the irradiation port of the ion beam generator 2 .

Superconducting materials include, for example, Y-Ba-Cu, Y-Ba-C
u-0, La-Ba-Cu, La-Ba-Cu-0,
A flat material such as Eu-Ba-Cu or Eu-Ba-Cu-0 is used. Above this target substrate 4 is a film forming substrate 6 facing the sputtering gas 5 that will be generated.
is provided. The film-forming substrate 6 is made of, for example, Cu or HgO.
, SrT io+ or the like is used.

Next, the method of the present invention will be explained using the apparatus as described above.

First, the inside of the closed container 1 and the ion beam generator 2 are evacuated by the exhaust system to create a vacuum atmosphere, and then a high voltage pulse is generated by the Marx high voltage generator of the high voltage pulse power supply 3 for the ion source. The waveform of the voltage pulse is shaped by the Blumlein waveform shaping circuit of the high-voltage pulse power supply 3 for the ion source. Then, this waveform-shaped high voltage pulse is applied to the ion beam generator 2. Then, the ion beam generator 2 instantaneously generates a high-pressure pulsed ion beam 7 and irradiates it toward the target substrate 4 made of the superconducting material. This high-pressure pulsed ion beam 7
The surface of the target substrate 4 is instantaneously turned into plasma in a non-thermal equilibrium manner, and a highly active sputtering gas 5 is generated.

This sputtering gas 5 is pulsed onto the surface of the film forming substrate 6. This forms a superconducting film on the surface of the film-forming substrate 6 that has a nearly single-crystal structure and has extremely high orientation.

This is off! ! When the power is the same, if the target substrate 4 is continuously irradiated with a continuous ion beam, a low voltage must be applied, but if the ion beam is irradiated instantaneously, a high voltage can be applied. Then, by shaping the waveform of this high-voltage pulse, it becomes a steep short pulse, and when this is applied to the ion beam generator 2, the ion beam is irradiated onto the target substrate 4 as a high-voltage pulsed ion beam 7. .

Therefore, the sputtering gas 5 generated from the target substrate 4
The superconducting film is instantaneously implanted into the film-forming substrate 6, and the superconducting film is formed intermittently at high speed, and its crystal becomes close to a single crystal structure and has strong orientation. This makes it possible to significantly increase the flow density (Jc) for saturation of the superconducting film.

[Effects of the Invention] In summary, according to the present invention, a target substrate made of a superconducting material is instantaneously irradiated with a high-pressure pulsed ion beam to generate sputtering gas, thereby forming a superconducting film on the surface of the film-forming substrate. Therefore, the sputtering gas is pulsed onto the surface of the film-forming substrate, making it possible to produce a superconducting film that is close to a single crystal structure, has extremely strong orientation, and is thick. This results in a large saturation current density (J
c).

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram for explaining the method of manufacturing a superconducting film of the present invention. In the figure, 1 is a sealed container, 2 is an ion beam generator, 3 is a high-voltage pulsed power source for an ion source, 4 is a target substrate, 5 is a sputtering gas, 6 is a film forming substrate, and 7 is a high-pressure pulsed ion beam.

Claims (1)

[Claims] A waveform-shaped high voltage pulse is applied to an ion beam generator, and a high-pressure pulsed ion beam is instantaneously generated from the generator and irradiated onto a target substrate made of a superconducting material in a vacuum atmosphere to generate sputtering gas. A method for producing a superconducting film, characterized in that the superconducting film is formed on the surface of a film-forming substrate.