JPS63276822A - Patterning method for superconductive thin film - Google Patents

Abstract

PURPOSE:To facilitate manufacture by forming a thin film, capable of being changed to be superconductive, on a substrate and radiating laser beams to make the film superconductive to form a circuit pattern. CONSTITUTION:A thin film capable of being changed to be superconductive by annealing processing, that is, a thin film 2 of e.g., a Y-Ba-Cu-O or LaSr(or Ba,Se)-Cu-O system is formed on a substrate 1 made of MgO single-crystal or the like. Laser beams 3 of CO2 gas laser are radiated to make this film superconductive to form a circuit pattern. Single-crystal of either one of MgO, TiO2, Sr, TiO3, Al2O3, YSZ is used for the substrate.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for forming a wiring pattern of a superconducting film on a substrate, and the wiring pattern thus formed is used in electronics, electronic computers, electric power, etc. used in various fields.

(Prior Art) Conventionally, when attempting to construct an electrical wiring pattern using a superconductor, superconductors formed in advance are pasted onto a substrate according to a desired pattern, or sputtering is performed by using a mask on the substrate. It has been considered to form a superconducting film using a method such as a method, EB black coating, or CVD method to form a superconducting pattern on a substrate.

(Problems to be Solved by the Present Invention) However, the former method of forming a wiring pattern requires manual construction of the circuit pattern, making it difficult to form fine patterns, and the latter method forms a pattern on a substrate. However, this method requires a step to prepare the mask pattern, which has a disadvantage in that it is not possible to form various circuit patterns immediately.

(Means for Solving the Problems) The present invention has been made in view of the above points, and involves forming a thin film that is likely to become superconducting on a substrate, and then irradiating the thin film with a laser beam according to the pattern to be formed. The method of patterning a superconducting thin film is characterized in that the thin film is made superconductive by forming a superconducting pattern on a substrate.

(Function) When a laser beam is irradiated onto a thin film that changes into a superconductor by heating means, only the portion of the thin film that is irradiated with the laser beam changes into a superconductor. Therefore, if laser beam irradiation is performed in accordance with the desired pattern, a circuit pattern made of a desired superconductor can be formed by the rapid cooling effect of laser annealing.

(Example) The following will explain the examples shown in Figures 1 and 2. In Figure 0, (1) is a substrate made of MgO single crystal <100> material, and (2) is a substrate that changes to superconductivity by annealing. Y-Ba-Cu-0 based thin film, (3) is a laser beam from a CO, gas laser. First board (1)
A thin film (2) is formed on one side of the substrate fi+, which is polished on both sides.This formation is performed as follows.

Oxides of metals and various rare earths (YtOa+ 1-azO
s+ 5ctOz) or carbonate (BaCOs+ 5ctOz)
After weighing rCO3) and CuO or CuzO, they are mixed well in a mortar. After that, preliminary sintering is performed if necessary. Thereafter, if necessary, the pre-sintered material is crushed and mixed again and pressed or fired at 800°C to create an ingot with a thickness of 2 inches and a diameter of 4 inches.Next, using the oxide or ingot as a target, The temperature of the substrate (1) is set to 450℃.
°C, atmosphere with an Ar to island ratio of 1:1, gas pressure 10 mt
A thin film (2) having a thickness of 0.5 nm was formed on the substrate (1) by high frequency magnetron sputtering with orrsRf power of 300-. The Y-Ba-Cu-0-based thin film (2) thus produced did not exhibit superconducting properties.

Next, Cog with oscillation wavelength 10.6 #Il and beam diameter 2 days Φ
The gas laser beam is focused by a Zn5e condenser lens with a focal length of 100 mm, and the focused spot diameter is 11 mm.
A 00P laser beam (3) is created, and a thin film (2
) to make this part superconducting. In Fig. 2, (4) shows a superconducting pattern constructed by irradiating a laser beam (3) onto a thin film (2). A desired circuit pattern can be easily formed by irradiation. To irradiate the thin film (2) with the laser beam (3), the laser beam (3) is fixed and the thin film (2) is irradiated with the laser beam (3).
) is formed on the substrate il+ by a step motor.
- Place the substrate (1
) by moving. It was confirmed that the circuit pattern formed in this way exhibited superconducting characteristics at 90''.

In the above embodiment of the present invention, the substrate (1) is MgO, the thin film (2) is a Y-Ba-Cu-0 thin film, and the laser beam (
3) describes only the case where the Cot gas laser is used and the thin film is formed by the sputtering method.
Sr Ding! Os+All0fflYSZ single crystal, La-5r-Cu-0 thin film, YAG laser or A
Similar effects can also be achieved by methods such as r gas laser, electron beam evaporation, CVD, and sintering.

(Effects of the Invention) As described in detail above, the present invention forms a thin film that becomes superconducting by heating it on a substrate, and then irradiates the thin film with a laser beam according to the pattern to be formed. This method of patterning a superconducting thin film is characterized by making the thin film superconducting and forming a superconducting pattern on a substrate, and has the excellent effect of making it possible to extremely easily create a circuit pattern using a superconductor.

[Brief explanation of drawings]

FIG. 1 is a side view of essential parts for explaining one embodiment of the present invention;
FIG. 2 shows a plan view of a circuit pattern created according to an embodiment of the present invention. (1) is the substrate, (2) is the thin film, and (3) is the laser beam. Patent applicant Furukawa Electric Co., Ltd. Figure 1 Figure 2

Claims (5)

[Claims] (1) A thin film capable of becoming superconducting is formed on a substrate, and then a laser beam is irradiated onto the thin film according to the pattern to be formed to make the thin film superconducting, thereby forming a superconducting pattern on the substrate. A method for patterning superconducting thin films. (2) The method for patterning a superconducting thin film according to claim 1, wherein the laser beam is any one of a CO_2 gas laser, a YAG laser, and an Ar gas laser. (3) The thin film is Y-Ba-Cu-O based or La-S
3. A method for patterning a superconducting thin film according to claim 1 or 2, characterized in that the superconducting thin film is made of r(orBaorSe)-Cu-O system. (4) The substrate is MgO, TiO_2, SrTiO_3,
A method for patterning a superconducting thin film according to any one of claims 1 to 3, characterized in that the superconducting thin film is made of either Al_2O_3 or YSZ single crystal. (5) The thin film is formed by any one of sputtering, electron beam evaporation, CVD, and sintering.
4. A method for patterning a superconducting thin film according to any one of Items 4 to 4.