JP2000124513A - Oxide superconducting device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form a contact hole while keeping dielectric strength by using an In2O3 as an interlayer insulation film in an oxide superconducting device having laminated superconductive joint. SOLUTION: An oxide superconductor thin film 2, a normal conduction thin film 3 and an oxide superconductor thin film 4 are piled up on a substrate 7 in sequence by sputtering so as to form an SNS type Josephson junction, and they are all made of single oriented polycrystalline thin film. Next, they are sputtered at the specified temperature in an oxidative gas atmosphere using the In2O3 as a target, thereby laminating an In2O3 film 5 on the entire surface thereof to form an interlayer insulation film. Thus, while keeping dielectric strength, a contact hole can be formed easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxide superconducting device and a method of manufacturing the same, and more particularly, to an In ₂ oxide that is physically soft as an interlayer insulating film and can be laminated with an oxide superconductor. The present invention relates to an oxide superconducting device characterized by using O ₃ and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, various superconducting devices have been developed using metal-based superconductors such as Nb. In particular, Josephson junction devices have been studied as a central device. Various superconducting junctions have been fabricated using high-temperature superconductors and other oxide superconductors that can operate at the temperature of liquid nitrogen. In a conduction quantum interference device (SQUID), a digital device, or a high-frequency device (microwave mixer), performance exceeding that of a conventional semiconductor device is expected.

In order to realize a high-speed and low-power-consumption oxide superconducting integrated circuit device using such a superconducting junction, amplification for connecting to a superconducting junction or a semiconductor device with little variation in element characteristics is required. An element having a function is required.

As a superconducting element structure constituting such a superconducting integrated circuit device, a laminated structure is promising. In the case of this oxide superconductor, Nb / AlO _x -Al / N
Unlike the case of using a metal-based superconductor typified by a b-junction, a tunnel type in which a superconductor / insulator / superconductor (SIS) is laminated is caused by manufacturing in a high-temperature oxygen atmosphere. Since it becomes very difficult to make Josephson junction operation, superconductor / normal conductor / superconductor (SNS)
Various Josephson junction devices using junctions have been tried.

For example, as a Josephson junction having a laminated structure using a barrier layer, a YBCO
(YBa ₂ Cu ₃ O _7-x ) oxide superconductor thin film, PBC
A barrier layer made of O (PrBa ₂ Cu ₃ O _7-x ) and a YBCO oxide superconductor thin film are sequentially deposited to form a flat Josephson junction, and then an SNS type Joseph is formed by forming a mesa structure. Attempts have been made to construct son junction elements.

[0006]

However, in such a Josephson junction device having a laminated structure, the oxide superconductor thin film constituting the Josephson junction device is composed of a single oriented polycrystal. PB as interlayer insulating film
CO (PrBa ₂ Cu ₃ O _7-x ), CeO ₂ , or
Insulators that can achieve crystal matching, that is, lattice matching with oxide superconductors such as YSZ (YSrZrO) are used. However, these insulators are physically hard, so that it is difficult to form contact holes. There is a problem.

In general, when an electrode for a Josephson junction element is provided, a contact hole is formed in an interlayer insulating film by ion milling using Ar ions, but an oxide such as YBCO is used as the interlayer insulating film. Since an insulator such as PBCO, which is physically as hard as the superconductor, is used, the etching rate is reduced and the selective etching property for the oxide superconductor cannot be obtained.

On the other hand, in order to shorten the time for forming the contact hole, the interlayer insulating film may be formed thin, but this causes a problem that the insulation on the side surface of the junction in the mesa cannot be sufficiently ensured.

Further, the above-mentioned insulator such as PBCO has a large relative dielectric constant of 40 to 100 and a large signal delay due to parasitic capacitance. Therefore, a superconducting integrated circuit device requiring high-speed operation can be manufactured. It was difficult.

Therefore, an object of the present invention is to use a physically soft In ₂ O ₃ as an interlayer insulating film and to facilitate the formation of a contact hole while maintaining a dielectric strength voltage.

[0011]

FIG. 1 is an explanatory view of the principle configuration of the present invention. Referring to FIG. 1, means for solving the problems in the present invention will be described. See FIG. 1A. (1) The present invention is characterized in that In ₂ O ₃ is used as an interlayer insulating film 5 in an oxide superconducting device having a stacked superconducting junction 1.

As described above, by using physically soft In ₂ O ₃ as the interlayer insulating film 5, it is possible to obtain selective etching properties with respect to oxide superconductors such as the oxide superconductor thin films 2 and 4. Since the contact holes can be easily formed even if the interlayer insulating film 5 is formed thick, the oxide superconductor thin film 2 / normal conducting thin film 3 / oxide superconducting film is formed by forming the interlayer insulating film 5 thick. The insulation of the side surface of the laminated superconducting junction 1 composed of the body 4 can be sufficiently ensured.

In addition, even if the single orientation of In ₂ O ₃ itself is insufficient, the upper interconnect 6
The use of In ₂ O ₃ is also desirable from this point of view because the oxide superconductor such as the above has excellent single orientation. Since the relative dielectric constant of In ₂ O ₃ is about 20 which is smaller than the conventional interlayer insulating film 5 for an oxide superconducting device, high-speed operation is possible.

(2) Further, in the present invention, in the above (1), the interlayer insulating film 5 is the interlayer insulating film 5 provided between the lower wiring and the upper wiring 6 of the laminated superconducting junction 1. Features.

As described above, the interlayer insulating film 5 in which In ₂ O ₃ is provided between the lower wiring and the upper wiring 6 of the multilayer superconducting junction 1 is provided.
By using, the side wall portion of the laminated superconducting junction 1 can be sufficiently protected, and the single orientation of the upper wiring 6 can be kept good.

(3) The present invention is characterized in that, in the above (1) or (2), In ₂ O ₃ is unidirectionally oriented by crystallization.

As described above, In used as the interlayer insulating film 5
By orienting ₂ O ₃ by crystallization,
The single orientation of the oxide superconductor thin film serving as the upper wiring 6 provided thereon can be further improved, and thereby the critical temperature _Tc can be increased.

(4) The present invention is characterized in that in any one of the above (1) to (3), In ₂ O ₃ is used also as the interlayer insulating film 5 between itself and the ground plane. .

As described above, by using In ₂ O ₃ as the interlayer insulating film 5 between itself and the ground plane,
_The parasitic capacitance can be reduced without deteriorating the single orientation of the oxide superconductor thin film 2 constituting the laminated superconducting junction 1 provided on ₂ O ₃ .

(5) The present invention provides a method for manufacturing an oxide superconducting device having a laminated superconducting junction 1, wherein the interlayer insulating film 5 covering the laminated superconducting junction 1 is made of In ₂ O ₃
Is deposited using a sputtering method.

As described above, In ₂ O as the interlayer insulating film 5
₃ may be deposited by sputtering,
In this case, since the step coverage is excellent, the thickness of In ₂ O _{3 on} the side wall of the multilayer superconducting junction 1 can be increased, and sufficient insulation can be maintained.

(6) The present invention is characterized in that, in the above (5), sputtering is performed at a temperature at which In ₂ O ₃ is unidirectionally oriented by crystallization.

As described above, the single orientation of the oxide superconductor thin film serving as the upper wiring 6 to be deposited thereon is enhanced by performing the sputtering at a temperature at which In ₂ O ₃ is unidirectionally oriented by crystallization. be able to.

(7) Further, according to the present invention, there is provided a method for manufacturing an oxide superconducting device having a laminated superconducting junction 1, wherein the interlayer insulating film 5 covering the laminated superconducting junction 1 is made of In ₂ O ₃
Is deposited by a laser ablation method.

As described above, In ₂ O as the interlayer insulating film 5
₃ may be deposited by a laser ablation method, but in this case, the step coverage is somewhat inferior.

(8) The present invention also relates to the above (5) to (5).
In any of (7), In_TwoO _ThreeOf deposited
, Laminated superconducting junction 1 by back sputtering
In of the side wall_TwoO_ThreeCharacterized by increased film thickness
You.

[0027] In ₂ O ₃ is, for lateral growth rate due to the back sputtering is very fast, in this way, In ₂ O
By depositing ₃ and, in particular, depositing it by a laser ablation method and then back-sputtering, it is possible to improve the covering of the side wall of the laminated superconducting junction 1 and thereby to improve the insulation of the side wall. Can be high enough.

(9) In the present invention, in the above (8), the back sputtering is carried out at a temperature at which In ₂ O ₃ re-adhering to the side wall of the laminated superconducting junction 1 is unidirectionally oriented by crystallization. It is characterized by the following.

As described above, the In ₂ O ₃ re-adhering to the side wall of the stacked superconducting junction 1 is also crystallized, thereby oxidizing the upper wiring 6 deposited on the interlayer insulating film 5 including the side wall. Single orientation of the superconductor thin film can be enhanced.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A manufacturing process according to a first embodiment of the present invention will now be described with reference to FIGS. 2 and 3. In order to simplify the description, one Josephson junction will be described. Only shown. Referring to FIG. 2A, first, a thickness of, for example, 200 nm is formed on an LSATO (LaSrAlTiO) substrate 11 by using a sputtering method.
Of _{YBCO (YBa 2 Cu 3 O 7} -x) film 12, a thickness,
For example, an ITO film 13 having a thickness of 5 nm and a thickness of, for example, 10
A 0 nm YBCO film 14 is sequentially deposited.

In this case, the YBCO film 12 / ITO film 13
The superconductor / normal conductor / superconducting structure, that is, the SNS-type Josephson junction is formed by the / YBCO film 14, and these YBCO film 12, ITO film 13, and Y
The BCO films 14 are all composed of a single-oriented polycrystalline thin film.

Referring to FIG. 2B, a mesa 15 reaching the YBCO film 12 is formed by performing ion milling using Ar ions using a resist pattern (not shown) as a mask. The SNS junction in the mesa 15 constitutes a Josephson junction element.

[0033] Referring then FIG. 2 (c), the reference to In ₂ O ₃ as a target, 50 mT
Orr Ar: O ₂ = 9: 1 Under an oxidizing gas atmosphere,
At a substrate temperature of 700 to 860 ° C., for example, 800 ° C., a thickness of 20
In ₂ O ₃ film 1 of 0 to 500 nm, for example, 300 nm
6 is deposited to form an interlayer insulating film. In this case, by setting the substrate temperature at the time of deposition to be sufficiently high, for example, 800 ° C. or higher, the single orientation of the deposited In ₂ O ₃ film 16 can be improved, and the deposition can be performed in an oxygen atmosphere. By doing so, oxygen deficiency in the In ₂ O ₃ film 16 can be eliminated, and thereby the In ₂ O ₃ film 16 can be a good insulator.

Referring to FIG. 3D, using a resist pattern (not shown) as a mask, ion milling is again performed using Ar ions to form a contact hole 17 reaching the YBCO film 14 on the top of the mesa 15. I do. In this case, In
_The etching rate of Ar ions of ₂ O ₃ is YB
Since it reaches about 3.5 times that of CO and is physically softer than YBCO, the contact hole 17 can be formed accurately without excessively etching the surface of the YBCO film 14.

Next, a YBCO film having a thickness of, for example, 300 nm is again deposited on the entire surface by sputtering, and then Ar ions are used using a resist pattern (not shown) as a mask. The basic configuration of the oxide superconducting integrated circuit device is completed by forming the YBCO upper wiring layer 18 by performing ion milling.

In the first embodiment, since physically soft In ₂ O ₃ is used as the interlayer insulating film, even if the In ₂ O ₃ film 16 is formed to be as thick as about 500 nm, the contact hole is formed. 17 can be formed with high accuracy.
Since it can be covered with the ₂ O ₃ film 16, the insulation of the SNS junction exposed on the side wall of the mesa 15 can be kept sufficiently high.

In addition, even when In ₂ O ₃ does not have a sufficient single orientation, the single orientation of the oxide superconductor thin film deposited thereon can be increased.
The single orientation of the BCO upper wiring layer 18 is also sufficiently high, so that the critical current Tc can be increased.

Further, In ₂ O ₃ has a relative dielectric constant of about 20 and is a PBC which has been used as a conventional interlayer insulating film.
Since it can be reduced to １ ／ or less as compared with 40 to 100 of an insulator such as O, the parasitic capacitance based on the relative dielectric constant of the interlayer insulating film can be reduced, thereby reducing the signal delay. Thus, high-speed operation of the superconducting device can be realized.

Next, a manufacturing process according to the second embodiment of the present invention will be described with reference to FIGS. 4 and 5. In this case, too, one Josephson Only the joint is shown. Referring to FIG. 4A, first, just as in the first embodiment, the LSAT
The YBCO film 12 having a thickness of, for example, 200 nm is formed on the O substrate 11 by using a sputtering method.
nm of the ITO film 13 and a thickness of, for example, 100 n
m YBCO films 14 are sequentially deposited.

Referring to FIG. 4B, a mesa 15 reaching the YBCO film 12 is formed by performing ion milling using Ar ions using a resist pattern (not shown) as a mask.
A Josephson junction element composed of an S junction is formed.

Next, as shown in FIG. 4C, using In ₂ O ₃ as a target, 10 ⁻² T
Under oxygen gas pressure of orr, 700-860 ° C, for example,
By using a laser ablation method of irradiating a target at a substrate temperature of 800 ° C.,
I having a thickness of 200 to 500 nm, for example, 300 nm
Although an n ₂ O ₃ film 19 is deposited to form an interlayer insulating film, the step coverage of the laser ablation method is inferior to that of the sputtering method. Therefore, the thickness of the In ₂ O ₃ film 19 on the side wall of the mesa 15 is small. Become. Also in this case, by setting the substrate temperature at the time of deposition to be sufficiently high, for example, 800 ° C. or higher, the single orientation of the deposited In ₂ O ₃ film 19 can be improved.

Next, as shown in FIG. 5D, the Ar gas pressure is increased to, for example, 10^-FourTorr,
When the substrate temperature is, for example, 800 ° C., the diameter is 2
300V, 20mA power between 0cm parallel plate electrodes
Apply for 5 minutes for ion milling with Ar ions 20
Therefore In_TwoO _ThreePerform back sputtering of the film 19
This allows the sputter etched In_TwoO_ThreePart of
Is attached again to the side wall of the mesa 15 and the thickness is, for example, 50
0 ° (= 50 nm) In_TwoO_ThreeThe reattachment part 21 is formed
As a result, the thickness of the interlayer insulating film covering the side wall of the mesa 15 is increased.
Become. This is In_TwoO_ThreeCompared to other insulating materials
Very high lateral growth rate by back sputtering
It is something that actively uses the nature.

After that, as in the first embodiment, ion milling using Ar ions is performed using a resist pattern (not shown) as a mask. A contact hole 17 reaching the top YBCO film 14 is formed.

Next, a YBCO film having a thickness of, for example, 300 nm is again deposited on the entire surface by sputtering, and Ar ions are used using a resist pattern (not shown) as a mask. The basic configuration of the oxide superconducting integrated circuit device is completed by forming the YBCO upper wiring layer 18 by performing ion milling.

The In ₂ O ₃ reattached portion 21 and the In ₂ O ₃
If the single orientation of the interlayer insulating film composed of the O ₃ film 19 is not sufficient, the single orientation of the YBCO upper wiring layer 18 deposited thereon is not necessarily sufficient.
By increasing the thickness of the BCO upper wiring layer 18, the critical temperature _Tc can be kept within a predetermined range.

In the _second embodiment, In ₂
As a method of depositing O ₃ , a laser ablation method that does not always provide sufficient step coverage is used. However, since the thickness of the interlayer insulating film covering the side wall of the mesa 15 is increased by performing back sputtering after the deposition, the mesa 15 The insulating property of the SNS junction exposed on the side wall of the semiconductor device can be kept sufficiently high. Other features are exactly the same as those of the first embodiment.

Next, the manufacturing process according to the third embodiment of the present invention will be described. The drawing is completely different from the second embodiment only in the conditions in the back sputtering process according to the second embodiment. Since it is the same, description will be made by borrowing FIGS. Referring again to FIG. 4A, first, just as in the first embodiment, the LSAT
The YBCO film 12 having a thickness of, for example, 200 nm is formed on the O substrate 11 by using a sputtering method.
nm of the ITO film 13 and a thickness of, for example, 100 n
m YBCO films 14 are sequentially deposited.

Referring to FIG. 4B, a mesa 15 reaching the YBCO film 12 is formed by ion milling using Ar ions using a resist pattern (not shown) as a mask.
A Josephson junction element composed of an S junction is formed.

Next, as shown in FIG. 4C, 10 ⁻² T was ^measured using In ₂ O ₃ as a target.
Under oxygen gas pressure of orr, 700-860 ° C, for example,
By using a laser ablation method of irradiating a target at a substrate temperature of 800 ° C.,
I having a thickness of 200 to 500 nm, for example, 300 nm
An n ₂ O ₃ film 19 is deposited to form an interlayer insulating film.

Next, as shown in FIG. 5D, in the same chamber, the Ar gas pressure
For example, 10^-FourTorr and substrate temperature of 700 to 860
° C, for example, at 800 ° C, with a diameter of 20 cm.
300V, 20mA power applied between parallel plate electrodes for 5 minutes
In addition, ion milling with Ar ions 20
n_TwoO_ThreeBy performing back sputtering of the film 19
The thickness of the side wall of the mesa 15 is, for example, 500 mm.
In_TwoO _ThreeA reattachment part 21 is formed. In this case,
Since the substrate temperature during back sputtering is sufficiently high,
In re-adhered to the side wall of the mesa 15_TwoO_ThreeReattachment part 21
Crystallization progresses and shows good single orientation.

After that, as in the first embodiment, ion milling using Ar ions is performed by using a resist pattern (not shown) as a mask. A contact hole 17 reaching the top YBCO film 14 is formed.

Next, a YBCO film having a thickness of, for example, 300 nm is again deposited on the entire surface by sputtering, and then Ar ions are used using a resist pattern (not shown) as a mask. The basic configuration of the oxide superconducting integrated circuit device is completed by forming the YBCO upper wiring layer 18 by performing ion milling.

[0053] In the third embodiment, since the crystallized In ₂ O ₃ reattached portion 21 by the substrate temperature to a high temperature during the back sputtering, an In ₂
The single orientation of the YBCO upper wiring layer 18 deposited on the interlayer insulating film composed of the O ₃ redeposition portion 21 and the In ₂ O ₃ film 19 can be sufficiently improved, and thereby the critical temperature _Tc can be further improved. Can be higher. The other features are the same as in the second embodiment.

Next, the manufacturing process according to the fourth embodiment of the present invention will be described.
The process will be described with reference to FIG. 6 and FIG.
Only one Josephson junction for simplicity
Is shown. Referring to FIG. 6A, first, on the LSATO substrate 11, a sputtering method is used.
YB made of a 100 nm thick YBCO film, for example
After the CO ground plane 22 is provided, In _TwoO_ThreeTo
Ar: O at 50mTorr used as target_Two=
700-860 ° C under 9: 1 oxidizing gas atmosphere, for example
For example, sputtering at a substrate temperature of 800 ° C.
Has a thickness of, for example, 100 nm
In_TwoO_ThreeThe film 23 is deposited, and then the thickness is
For example, a 200 nm YBCO film 12 having a thickness of, for example, 5
nm of the ITO film 13 and a thickness of, for example, 100 n
m YBCO films 14 are sequentially deposited.

Also in this case, the substrate temperature at the time of depositing the In ₂ O ₃ film 23 is made sufficiently high, for example, 800 ° C. or more, so that the single orientation of the deposited In ₂ O ₃ film 23 is improved. The YBCO film 12, the ITO film 13, and the YBCO film 1 deposited thereon.
4 can maintain good single orientation.

Referring to FIG. 6B, thereafter, the YBCO film 1 is formed by performing ion milling using Ar ions using a resist pattern (not shown) as a mask in the same manner as in the first embodiment.
2 are formed to form a Josephson junction element composed of an SNS junction.

[0057] Referring then FIG. 6 (c), the reference to In ₂ O ₃ as a target, 50 mT
Orr Ar: O ₂ = 9: 1 Under an oxidizing gas atmosphere,
At a substrate temperature of 700 to 860 ° C., for example, 800 ° C., a thickness of 20
In ₂ O ₃ film 1 of 0 to 500 nm, for example, 300 nm
6 is deposited to form an interlayer insulating film.

Referring to FIG. 7D, ion milling using Ar ions is again performed using a resist pattern (not shown) as a mask to form contact hole 1 reaching the top of mesa 15 again.
7 is formed.

Next, a YBCO film having a thickness of, for example, 300 nm is deposited on the entire surface again by sputtering, and then Ar ions are used using a resist pattern (not shown) as a mask. The basic structure of the oxide superconducting integrated circuit device having the ground plane is completed by forming the YBCO upper wiring layer 18 by performing the ion milling.

In the fourth embodiment, even when a ground plane is provided, since the In ₂ O ₃ film 23 is used as an interlayer insulating film provided thereon, the YBCO film 12 deposited thereon is used. , ITO film 13 and YB
The single orientation of the CO film 14 can be kept good, and the contact hole can be easily formed even when the ground is taken out from the YBCO ground plane 22.

When an oxide superconducting integrated circuit device having such a ground plane is formed, In ₂ O ₃
The film 16 is formed in the same manner as in the second and third embodiments.
The deposition may be performed by using a laser ablation method. In this case, back sputtering is performed in the same manner as in the second and third embodiments, and particularly, 800 nm in the same manner as in the third embodiment. It is desirable to perform back sputtering in a high temperature atmosphere of about ° C.

The embodiments of the present invention have been described above. However, the present invention is not limited to the conditions and configurations described in the embodiments, and various changes can be made. For example, in the description of each of the above embodiments, YBCO (YBa ₂ Cu ₃ O _7-x ) is used as the oxide superconductor. However, the present invention is not limited to YBCO, and Bi (SrCa ) CuO, Tl (BaCa) Cu
It goes without saying that other known oxide superconductors such as O or Hg (BaCa) CuO may be used.

In the description of each of the above embodiments, the sputtering method is used as the method of depositing the oxide superconductor. However, the method is not limited to the sputtering method.
A PE method (metal organic chemical vapor deposition) or a laser ablation method may be used. In the case where the laser ablation method is used, a manufacturing apparatus is used by using the laser ablation method also as a deposition method of In ₂ O _3. Can be used in common, thereby simplifying the manufacturing process.

In the above description of the first and fourth embodiments, since the sputtering method is used as the method for depositing the In ₂ O ₃ film 16, back sputtering is not performed. When the covering of the side wall portion of the mesa 15 is not sufficient even when the sputtering method is used, for example, when the sputtering method is high, a back sputtering step may be added similarly to the second or third embodiment. Things.

[0065] On the contrary, in the case of using a laser ablation method as a deposition method of In ₂ O ₃ film 19, or when the height of the mesa 15 is low, an In ₂ O sidewall of the mesa 15
_When the thickness of the _three films 19 is sufficient, the back sputtering step is not always necessary.

[0066]

According to the present invention, the interlayer insulating film provided between the upper wiring layer and the lower wiring layer of the laminated superconducting junction is made of a physically soft and low-dielectric-constant In ₂ O _3. Therefore, even if an interlayer insulating film is formed thick in order to enhance the insulating property of the side wall of the mesa, it is easy to form the contact hole, thereby facilitating circuit application and integration, Also, since the parasitic capacitance can be reduced, it greatly contributes to high-speed operation of various digital circuits and microwave devices.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a basic configuration of the present invention.

FIG. 2 is an explanatory diagram of a manufacturing process partway through the first embodiment of the present invention.

FIG. 3 is an explanatory view of a manufacturing process of the first embodiment of the present invention after FIG. 2;

FIG. 4 is an explanatory diagram of a manufacturing process partway through a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of a manufacturing process after FIG. 4 according to the second embodiment of the present invention.

FIG. 6 is an explanatory diagram of a manufacturing process partway through a fourth embodiment of the present invention.

FIG. 7 is an explanatory diagram of a manufacturing process of the fourth embodiment of the present invention after FIG. 6;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 laminated superconducting junction 2 oxide superconductor thin film 3 normal conducting thin film 4 oxide superconductor thin film 5 interlayer insulating film 6 upper wiring 7 substrate 11 LSATO substrate 12 YBCO film 13 ITO film 14 YBCO film 15 mesa 16 In ₂ O ₃ film 17 Contact hole 18 YBCO upper wiring layer 19 In ₂ O ₃ film 20 Ar ion 21 In ₂ O ₃ reattachment part 22 YBCO ground plane 23 In ₂ O ₃ film

Claims (9)

[Claims] 1. An oxide superconducting device having a stacked superconducting junction, wherein In ₂ O ₃ is used as an interlayer insulating film. 2. The oxide superconducting device according to claim 1, wherein the interlayer insulating film is an interlayer insulating film provided between a lower wiring and an upper wiring of the stacked superconducting junction. 3. The oxide superconducting device according to claim 1, wherein the In ₂ O ₃ has a single orientation by crystallization. 4. The oxide according to claim 1, wherein In ₂ O ₃ is also used as an interlayer insulating film between the oxide superconducting device and a ground plane. Superconducting equipment. 5. A method for manufacturing an oxide superconducting device having a stacked superconducting junction, wherein In ₂ O ₃ is deposited by a sputtering method as an interlayer insulating film covering the stacked superconducting junction. A method for manufacturing an oxide superconducting device, which is characterized in that: 6. The temperature at which the In ₂ O ₃ is single orientation by crystallization method of manufacturing an oxide superconductor according to claim 5, wherein the sputtering In ₂ O _3. 7. A method of manufacturing an oxide superconducting device having a laminated superconducting junction, wherein In ₂ O ₃ is deposited by a laser ablation method as an interlayer insulating film covering the laminated superconducting junction. Of manufacturing an oxide superconducting device. 8. After the deposition of the In ₂ O _3, by a back sputtering of claims 5 to 7, characterized in that the increased thickness of the In ₂ O ₃ of the side wall of the stacked superconducting junction A method for manufacturing an oxide superconducting device according to any one of the preceding claims. The method according to claim 9, wherein said back sputtering, oxide of claim 8, wherein the In ₂ O ₃ to be re-attached to the side wall of the stacked superconducting junction and performing at temperatures of single orientation by crystallization Superconducting device manufacturing method.