JPS60178676A - Tunnel type josephson element and manufacture thereof - Google Patents

Abstract

PURPOSE:To enable easy manufacture by a method wherein the first superconductor electrode made of Nb having a required pattern is formed on a substrate with an Si oxide insulation film formed on the surface, and the second superconductor electrode made of Pb or Pb alloy or Nb is formed thereon. CONSTITUTION:A metallic layer 3 made of Al or Cr is formed on the Si oxide insulation film 1. Next, the superconductor layer 4 made of Nb is formed on the metallic layer 3 made of Al or Cr, and a mask layer 5 made of photo resist having a required pattern is formed thereon. The first superconductor electrode 6 is formed by reactive sputter etching with the mask layer 5 as a mask. Then, a metallic layer 10 made of Al or Cr is formed on the first superconductor electrode 6 and an Al oxide insulation film 8. A tunnel barrier layer 11 made of Al oxide or Cr oxide is formed. The second superconductor electrode 14 made of Pb or Pb alloy or Nb is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a first superconductor electrode made of N I+ having a desired pattern formed on a substrate having an insulating film made of silicon oxide formed on the surface thereof. is formed, and Pb or Pb is formed on the first superconductor electrode via a tunnel barrier layer.
The present invention relates to a method for manufacturing a tunnel type Josephson element having a +i4 structure in which a second superconductor electrode made of an alloy or Nb is formed.

BACKGROUND OF THE INVENTION In a Schinnel-Josephson device having this 114 structure, the substrate on which the first superconductor electrode is formed is a substrate on which an insulating film is formed, and The insulating film of the substrate is made of silicon oxide. The insulating film made of silicon oxide formed on this substrate can be easily formed by vapor deposition at a low temperature.

Therefore, the Josephson element C1 having the above-described configuration has the characteristic that it can be easily manufactured. In the Jorenoson element, the first superconductor electrode formed on the substrate on which an insulating film of silicon oxide (2) is formed is made of Nb.N1)t''<Lth The superconductor electrode of No. 1 is formed on the surface of the substrate and has an insulating film made of silicon oxide, which has a relatively large difference in expansion coefficient. Given a thermal cycle between C and cryogenic temperature, λJ L
, the first superconductor electrode resists l−'l)J: or 1)1) alloy 4f. Therefore, when a thermal cycle between room temperature and a cryogenic temperature is applied to the C11~Nel Desired Lufson element, 1-
The risk of damaging the channel barrier layer is much lower than when the first superconductor electrode is made of Pb or a Pb gold alloy.

Further, in the tunneling Josephson device having the above-described structure, the second superconductor electrode is formed on the first superconductor electrode via a tunnel barrier layer, and the second superconductor electrode is formed on the first superconductor electrode through a tunnel barrier layer. It becomes. Even if the second superconductor electrode is made of pl+ or [)b alloy, N
Since C has a much smaller difference in coefficient of expansion between the first superconductor electrode made of B and the insulator 19 made of silicon oxide, the tunnel type Josephson element can be used at room temperature. Even given a thermal cycle between
The second superconductor ffi pole is hardly exposed to J3, which would damage the C tunnel barrier layer.

Therefore, C1, [tunnel type di? ] The Lefson element is characterized by its ability to operate and exhibit the desired characteristics even when a heat quantity between room temperature and extremely low temperature is applied to the tunnel-type Josephson element.

In the above-mentioned 1-thickness Josephson device of 414 compositions, which has such characteristics, conventionally, a 1-thin-thickness barrier layer interposed between the first and second superconductor electrodes was used. , the first superconducting (N1 where the surface of the A electrode is oxidized to form C) oxide (Nll + O+
) “C is concave.

This Ntl oxide is similar to AIL oxide (ΔL+O+) and C
1. Has a higher dielectric constant than oxides (Orl, 0+).

For this reason, the conventional tunnel type di-E11? having a series of configurations in which the tunnel barrier layer is made of NbM compound. In the case of Takako Fuson, the capacitance between the first and second superconductor layers (
Compared to the case where the I-channel barrier layer is made of ΔL oxide (Y) c + M oxide (e), it is larger for the same thickness and area of the I-channel barrier layer.

Therefore, in the case of the above-mentioned conventional 1-layer type diode having a 1-layer barrier layer consisting of Nl + oxide, the 1-layer barrier layer is made of Am oxide or Cr oxide; This has the disadvantage that it cannot be operated at a switching speed as fast as in case b.

Furthermore, the tunnel-type Josephson element having the above-described features and having the above-mentioned structure has a superconductor layer made of Nb formed on a substrate on which an insulating film made of silicon oxide is formed on the surface, Normally, the superconductor layer is manufactured by etching the superconductor layer 9" to form a first superconductor electrode having a desired pattern from the superconductor layer.

By the way, in the step of forming the first superconductor electrode in which a desired pattern is formed from the superconductor layer by the L etching process on the superconductor layer, the etching process for the superconductor layer is -C1. Conventionally, a one-tetching process using a chemical solution for etching and a dry etching process using a reactive sputter etching process using CF or gas have been proposed.

However, when using a chemical etching solution, 1-
In the case of the 1-to-1 Tubung process, during the process of forming the first superconductor layer 1, the 1 Tubung River chemical solution flows around the side surface of the first superconductor electrode. The superconductor electrodes are connected to each other. For this reason, the first superconductor electrode 14 is formed by relatively thick n'i side etching, and the first superconductor electrode is formed into a fine pattern of 2 μm or less. Trouble
Met. This I,:1-channel type Jorenoson device with a high degree of integration is C! ! I can't make it,
He hated this shortcoming.

In the case of soil tucking treatment using 1v (chemical solution for tsuging), the first superconductor layer 1~
To form a pattern of 9j, the composition and purity of the etching chemical solution are strictly selected, and the temperature of the 1:1 etching chemical solution and the 1:1 etching distance are strictly controlled. Therefore, one drawback was that it was not possible to easily manufacture a one-channel type Johifson element.

Furthermore, -1-X[
In the case of hot etching, there is a problem in that toxic waste liquid is produced, which must be disposed of safely.
It has the following drawbacks.

j) In the case of dry etching treatment by reactive sputter etching treatment using CI''r gas, CF
+ By controlling the pressure of the gas, it is possible to control the etching rate for the superconductor layer, so that the first superconductivity >9 during the process of forming the first superconductor electrode.
The weight can be made sufficiently small. Therefore, the superconductor electrode of Ri 11 can be formed into a finer pattern than in the case of the wet etching process described above. .Therefore, tunnel type diH(2
This method has the characteristic that the Noson elements can be manufactured and covered with a higher degree of integration than in the case of the web 1 to etching process.

However, in the case of dry etching treatment by reactive sputter etching treatment using CF-gas, at a CFI gas pressure of less than 10 Pa, which provides a relatively slow etching speed, as shown in FIG. For an insulating film of silicon oxide C formed on the surface of
- The nipping speed is higher than the nipping speed for the Nb superconductor layer, so that the '1st superconductor electrode is between its surface and the surface of the substrate. The second superconductor electrode is then formed with a superconductor wire extending integrally from the second superconductor electrode to the substrate.
It has the disadvantage that it is difficult to extend it to a normal condition.

In addition, C1: Reaction 1 using gas ([sputtering
In the case of dry etching treatment, the first
As shown in the figure, the u1 conductor layer is made of N11]
30P where the ratio of the etching rate to the etching rate for the insulation 119 made of silicon oxide C is "1" or more.
In the case of Crt gas pressure from a to F, even if the number of skewers on which the insulating film made of silicon oxide is rolled is reduced, the pressure of CF gas is 11 (゛, N1 + t'').
The superconducting fA electrode of ￥T1 is relatively thick...→J idconitched, and therefore it has the disadvantage that it is difficult to form the first superconductor electrode in the desired pattern. Ta.

OBJECTS OF THE INVENTION The present invention proposes a novel tunnel-type Josephson device that does not have the above-mentioned drawbacks.

In addition, the present invention proposes a method for manufacturing a new tunnel type Jimin-Lenoson element, which allows the tunnel type Joffson element according to the present invention to be easily manufactured without having to suffer from the above-mentioned drawbacks. It is called U.

DISCLOSURE OF THE INVENTION According to the tunneling type Josephson device according to the first invention of the present application, the tunnel barrier layer interposed between the first and second superconducting weights 44i is different from the conventional tunneling type Al oxide (A, I), + Or ) or C, which has a lower dielectric constant than NbM9ide (Nll 20+ ), which constitutes the tunnel barrier layer of the Son element.
It is made of r oxide (Cr20!).

Therefore, the tunnel type Josephson device according to the first invention of the present application is different from the conventional one tunnel 41+! described above. According to the inventions No. 1, No. 2, and No. 3 of the present application, the invention operates at a higher switching speed than the Jollefson element.
- J: In the manufacturing method of the tunnel-type Jollefson element, 4T is applied to the surface with silicon oxide! l! A superconductor layer made of N 11 is formed on the substrate on which the edge film is formed, and the superconductor layer ip I is etched by etching the single superconducting layer. A tunnel-type Josephson device is fabricated by following the same pattern as the one forming the first superconductor electrode. N is formed on the substrate.
In one culm forming a river den V body layer consisting of +1, the table T
An insulating film of silicon oxide C' is formed on the substrate 1).A layer of ΔL, (/l", ΔL oxide or Cr oxide or gold oxide) is formed on the substrate. via Nb
A superconductor layer ′c is formed.

Furthermore, by etching the superconductor layer made of Nll, a first superconductor electrode made of Nb having a predetermined pattern is formed from the superconductor layer made of Nb. The etching treatment for the superconductor layer made of Nb is performed using a reaction using Crt gas or CB□r+ gas (41 sputter etching treatment).

However, when etching a superconductor layer made of r,Nb using a reactive sputter etching process using Crt gas, the IF force of the CF gas is applied to the silicon oxide of the substrate. Even if the etching speed for the insulating film is larger than the etching speed for the superconductor layer made of Nb, the etching speed for the superconductor layer made of N, l+ is The etching process produces Δ(L
, a metal or metal oxide layer made of Cr, Al oxide or Cr oxide is formed;
In this case, in the reactive sputter etching process using CF r gas, the pressure of the CF r gas is
The above mentioned tr! As shown in Figure 1, the etching rate of An, C1゛, ΔL oxide or lζ for a metal or metal oxide layer made of Cr oxide is higher than that of silicon oxide of the substrate. Compared to the etching rate for the C4f insulating film, the
・1 Riru-1. Since l''b is much faster than the sputtering speed, the reactive sputtering process using CF4 gas in this case is immediately effective C1ΔL, (Cr, △
J, the metal or metal oxide layer made of 1I dodecide or Cr oxide is heated so that the surface of the 34% plate becomes dewy.
Even if the first superconductor layer (t) is cut (t), and even if the surface of the board is not exposed, the first superconductor layer (
4I between the surface of A and the surface of the substrate or Δt, O
r, Δjl oxide or CrC metal J: l is metal t
I! There is a large step between the surface of the compound layer and the '11! '
It is C-monkey to form Ll without giving up.

In addition, the J-etching process for the super single conductor layer consisting of Nl+ was performed using reaction 1'l using 0L311''+ gas.
- Even when using sputter etching treatment, the etching treatment for the superconductor layer made of Nb is the same as the etching treatment for the superconductor layer made of Nb by reactive sputtering using CF1 gas. Similarly to the case of etching treatment, the substrate "2" is Δ41. CrAl7 (i-ide or CI-
A metal or metal oxide layer consisting of a fill compound is formed in -C, while in this case CBr F
In the reactive sputter etching process using i gas, even if the pressure of the CB1''F+ gas is in the range of 10 Pa or less, the etching process for the superconductor layer N1+'c can be performed using CF, a reaction using gas. Similarly to the case of the sputter etching process, and as shown in FIG. The etching speed is much slower than that for the conductor layer, so even if the CII "reactive sputter etching process using F l gas in this case is performed at d3, ΔL, Cr,
Even if the metal or metal oxide layer made of AfL oxide or Cr oxide is etched so as to expose and cover the surface of the substrate, it can also be etched to the extent that the surface of the substrate is not exposed. The electrodes are placed between the -ξ surface and the surface of the plate.
1. The gold 1rz round ζ has a C formation between the surface of the gold 11 base and the molten metal layer that does not tighten the 41st layer of metal.
Toga(゛kiru)

In addition, when the superconductor layer of Nll'C is subjected to a reactive sputtering treatment using Cl5rl:+ gas, the
As shown in FIG. 2, the etching rate curve for the four conductor layers is Δ(J,, Or, ΔL oxide or 01.
The etching speed for a metal or metal oxide layer made of oxide C is much faster than the etching speed for an insulating film made of a silicon oxide. The fast range of i11 Tubung Speed 1a is CBIF'F+
A low power range of less than 10 Pa of the gas is achieved. can be easily formed into the pattern 111J.

According to the invention of No. 2 and No. 3 of the present application [1], the manufacturing method of the Goyoru 1-Nel-type Dikorefson device is such that a first
After forming superconductor electrodes C, a Hennel type Josephson device is manufactured by forming a layer barrier layer on the first superconductor electrode.
3C1] - A channel barrier layer is formed of octoxide or Cr oxide.

Therefore, regarding the tunnel J'v according to the first invention of the present application to a Josephson element (J2)l-L1kokoro/)
As is clear from et al., it is possible to manufacture a tunnel-type Josephson device that operates at a high switching speed C.

Furthermore, according to the method for manufacturing a tunnel-type Josephson device according to the present invention, the substrate -[
After forming the first superconductor electrode on the substrate,
The method includes the step of forming an insulating layer made of silicon oxide in the region where the first superconductor electrode is not formed so as to fill the first superconductor electrode from the side.

For this purpose, the substrate is formed with a surface having no steps in contact with the surface of the first superconductor electrode, and the second superconductor electrode is integrally formed on the surface of the substrate. It is possible to easily avoid extending the superconductor wires that have been extended.

Furthermore, according to the method for manufacturing the 1- to 3-channel type Josephson device according to the invention of No. 3 of the present application, the first superconductor tlt 14j is formed on the substrate, and then the first superconductor tlt 14j is formed on the substrate. In the region where the first superconductor electrode is not formed,
Filling the first superconductor electrode from the side: First, an insulating film made of silicon oxide is formed, and then an insulating film made of silicon oxide C and the first superconductor electrode are filled through the insulating film. (A tunnel barrier layer made of a continuously extending ΔL oxide or 01゛ oxide is formed, and then on each tunnel barrier layer, 1) l) or 1] 1) alloy or N b 'c 13
Reactive sputtering using rF l gas [TSf'/
'J 9R 4CJ: -y U, JfJ biography in (
AIM Kaitsu, u12 G) Kawaden) R weight) Forming 41, [mode is S.

By the way, in the reactive sputtering process using CF, gas or CBr F3 gas to form the second superconductor electrode from the superconductor layer, an insulating film made of silicon oxide or Cr Etching polishing of a 1-thin oxide barrier layer is performed using CF, gas or CBrF.
Even if the gas pressure is in a low value range below 101)a, as shown in Figures 1 and 2, the superconductor layer 1)
bmalko is 1) b-1n-Δu, pb-Bi, etc.
[b alloy'at<> compared to the superconductor layer when the alloy is made of C, and also compared to the superconductor layer when the superconductor layer is made of N11, as mentioned above. , is significantly slower.

Therefore, the second superconductor electrode can be formed without creating a large step between the surface of the second superconductor electrode and the surface of the substrate, and the second superconductor electrode can be formed at a location of gJ. It can be easily formed into patterns.

Preferred Embodiments of the Invention Next, a preferred embodiment of the 4-W tunnel type Jollefson element according to the present invention and a method for manufacturing the same will be described below. : Let's say that.

Embodiment 1 Fig. 3 shows a first embodiment of the method for manufacturing a tunnel type J3'' Lefson element according to the present invention. A device is manufactured.

That is, the substrate 2 on which the insulating film 1 of silicon oxide r<c is formed is prepared in advance (see FIG. 3). In fact, this board 2 is, for example, a mass-market main body 2 made of silicon C.
A grounding η body layer 2b made of Nb is formed on a
On the 1a ground superconductor layer 211, silicon oxide C
An insulating film 1 is formed on the substrate 2, that is, an insulating film F made of silicon oxide is formed on the substrate 2. 1, a metal layer 3 of AL, OR, etc. is formed to a thickness of, for example, 40 to 110 by a method known per se (FIG. 3B).

Next, a superconductor layer 4 made of Nb is formed on the metal layer 3 made of Ai or Cr by a known method such as vapor deposition (for example, to a thickness of 2000 nm). Figure 3C
).

Next, on the superconductor layer 4, a mask layer 5 made of a resist film 11 with a desired pattern is formed to a thickness of, for example, about 1.5 μm by a method known per se.
Figure 3D).

Next, the superconductor layer 4 is subjected to a reactive sputter etching process using CF+ gas or CBIF'F+ gas using the mask layer 5 as a mask, so that the pattern of the mask layer 5 is formed from the superconductor layer 4. A first superconductor electrode 6 having a corresponding pattern is formed (FIG. 3E). In this case, the metal layer 3 made of AL or C is subjected to a reactive sputter T-etching process using -b, CF+ gas or CB+ gas, and from the metal layer 3, the pattern of the mask layer 5 is applied. A metal layer 7 was formed under the first superconductor electrode 6 having a pattern corresponding to the above.

However, CF,
When using gas, the CF and gas pressure should be set at 5 to 101
)a, and C for reactive sputter Ji etching treatment.
When using B rF r gas, the 1f force is 2 to 14
)) By taking a), the first superconductor N pole 6 is connected between its surface and the surface of the insulating film 1 with the thickness of the first superconductor electrode 6 and the metal layer. It was formed so as to have only a step approximately equal to the sum of the thickness.

Next, the first superconductor electrode 6 on the substrate 2 is formed -C
A first insulating layer 8 made of silicon oxide is applied to the area where the silicon oxide is not present.
6 to the superconductor layer 1 from the side, and the surface is approximately the same thickness as the surface of the first superconductor electrode 6, or is larger than the surface of the first superconductor electrode 6. It is formed by vapor deposition so that it has a slightly higher height (FIG. 3F).

In this case, an insulating layer 9 made of the same silicon oxide as the insulating layer 8 is formed on the mask layer 5.

Next, the mask layer 5 is dissolved away, and the insulating layer 9 is removed accordingly (FIG. 3G). In this case, the surface of the insulating film 8 is slightly etched, so that the insulating film 8 covers its surface with the first superconductor 1iII! Therefore, the surface of the first superconductor electrode 6 and the surface of the insulating film 8 were formed so as to have substantially no step.

Next, a first superconductor layer 411 (6) and an insulating film 8 made of silicon oxide are coated with -C extending through them.
A metal layer 10 of Al or Cr is formed, for example by means of vapor deposition methods known per se, to a thickness of, for example, 40 to 150 mm (FIG. 3).

Next, the metal layer 10 made of AL or Or is subjected to oxidation treatment, for example, plasma oxidation treatment.
0, it is oxidized to form At), M compound (AjL
+ 0+ ) or Cr oxide (Cr r O+ )F
A 1-channel barrier F111 is formed (Fig. 3, 1).
).

Next, the AL oxide or Ic is placed on the tunnel barrier layer 11 made of Cr oxide, ]]b or pl)-III-Δu,
A superconductor layer 12 consisting of a 1)11 alloy such as pb-3i or Nb is formed to a thickness of, for example, 4000 nm by a method known per se, for example by vapor deposition (FIG. 3J).

Next, a desired pattern is formed on the superconductor layer 120, for example, using a foot resist, which faces the first superconductor electrode 6 through the superconductor layer 12 and the channel barrier layer 11. A mask layer 133 is formed by a method known per se (FIG. 3K).

Next, for superconductor F1412, mask Fl1M'+
3 as a mask and 1: CCF + gas or CI3 r
F1. Reactive sputtering using a sputtering process to form a pattern corresponding to the pattern of the mask layer 13 from the superconductor layer 12 (1) or]) A second sputter made of alloy or Nb. 9. Form superconductor electrode 14 (Fig. 3L). In this case, AfL nitrate or C1
・Oxide r: The tunnel barrier layer 11 made of λ・1 [is subjected to reactive AL20. using C1:1 gas or Cl5rl''+ gas, but the C used for reactive sputter etching treatment is By reducing the LL force of the F+ gas to a low value of, for example, 1 to 1 opa, the barrier layer 11 is not substantially eroded, and therefore the second A second superconductor electrode 14 is provided between the surface of the superconductor electrode 14 and the surface of the tunnel barrier layer 11.
Superconductor layer 1f! It was formed to have only a step having a value approximately equal to the thickness of No. 14.

Next, the second superconductor electrode 1 on the tunnel barrier layer 11
4 is not formed, an insulating layer 15 made of silicon oxide is placed so as to fill the second superconductor layer 41i 1 /l from the side, and the surface is covered with the second superconductor electrode 14.
(Fig. 3M). In this case, an insulating film I Ci made of the same silicon oxide as the insulating film 15 is also formed on the mask layer 13 .

Next, the mask layer 13 is dissolved away, and the insulating film 16 on the mask layer 13 is removed accordingly (FIG. 3N).

As described above, a 1-channel type Fson element (N in FIG. 3) according to the present invention is manufactured.

Actual 771 Example 2 FIG. A second example of the method for producing Fuson element f is shown, and the following steps are carried out in the following steps.
The culm is removed and tunnel-type Josenoson material T is produced by Kizat Akira.

In other words, the present invention described in Figure 3 is 4cm)'C.
As in the case of the first embodiment of the method for manufacturing a tunnel-type Josephson device, a grounding superconducting layer 2b made of Nb is formed on a silicon oxide (1.C) substrate body 2a. A substrate 2 having a structure on which an insulating film 1 made of silicon oxide is formed is prepared in advance (FIG. 4A).

Next, as in the case of the first embodiment of the \J method of the tunnel-type Jorenoson element i- according to the present invention, the substrate 2 is curved, and the insulation R'A 11 made of silicon oxide is
Alternatively, a metal layer 3 made of Cr is formed (FIG. 4B).

Next, by oxidizing the metal layer 3 made of ΔL or Cr, for example, by plasma oxidation treatment, the metal layer 3 is oxidized to form an Al11m compound (Ant).
A metal oxide layer 17 made of O+ ) or cr oxide (CrO+) is formed (FIG. 4C).

Next, on the metal oxide layer 17, N
In the same way as forming the superconductor layer 4 made of Nb (FIG. 3C), a super decomposed S body layer 4 made of Nb is formed. The same steps as those described above for DN are taken.

In the manner described above, a one-channel type Josephson device according to the present invention is manufactured.

In addition, in the above description, only two embodiments have been shown for each of the tunnel type Josephson element and its manufacturing method according to the present invention. In the example of
G is formed by reactive sputter etching treatment using C1:, gas or (';l-31' F r gas [culm C1Δf
In the case of the first embodiment of the method for manufacturing a tunnel-type Josephson device according to the present invention, Al or Cr is etched into a metal oxide layer consisting of a LM compound or a Gr 1ift compound.
A process in which a metal oxide layer made of ΔL oxide or Or oxide corresponding to the metal layer 7 made of 1. Therefore, the group 3 oxide layer of ΔL oxide or Cr/lfi oxide is removed from the insulating layer of silicon 1 oxide of the substrate 2. A1, it extends beyond the first superconductor electrode 60 (it is also possible to manufacture a 14-layer di-J Refson element, etc.). Various modifications and changes may be made without departing from the essence of the present invention.

[Brief explanation of drawings]

Figure 1 △ and B show the conventional method for manufacturing a tunnel-type Josephson device, and the method for manufacturing a tunnel-type Josephson device according to the present invention. Insulating film made of metal, superconductor layer made of Nb, metal layer made of Ai, C
a metal layer consisting of r, a metal oxide layer consisting of AfL oxide, C
metal oxide layer consisting of rFiQ oxide, and pb or l]
b -1n-△u , Figure 1 shows the relationship between the IJ force (Pa) and the speed (h/min) of C F t gas in which a superconductor layer made of Pb alloy C such as pb-Bi is etched. be. FIGS. 2A and 2B illustrate the method for manufacturing a tunnel-type Jollefson device according to the present invention. The reaction using CBr21 gas ([sputtering process] produces an insulation made of silicon oxide If!). ), a superconductor layer made of Nb, a metal layer made of ΔL, a metal layer made of Or, a metal oxide layer made of an ALB compound, a metal oxide layer made of a CrM compound, and pb-In- A superconductor layer made of an E)b alloy such as Au or Pb-3i is etched.
The speed 1α (to /
This is a diagram showing the relationship between FIG. 3 is a cross-sectional view of the first embodiment of the method for manufacturing a tunnel W1 element according to the present invention, taken sequentially from one step to the next. FIG. 4 shows the second embodiment of the method for manufacturing the tunnel type di=+senosone device according to the present invention/II! It is a 181J cross-sectional view showing ilu+. 1・・・・・・・・・・・・・・・Silicon oxide insulating film 2・・・・・・・・・・・・Damage plate 2a
・・・・・・Board body 21+・・・・・・・・・・・・
・N b ′c1. ' = superconductor layer 3...
・・・・・・・・・Metal layer 4 consisting of △L and cr...Superconducting IA W#5 with Nll <2...・・・・・・・・・Mask layer 6・・・・・・・・・・・・First electrode made of Nb 7・・・・・・・・・...Metal layer ε3,9 made of Ai or Cr...Insulating film 11 made of silicon oxide... Tunnel barrier layer 12 made of AL1 oxide or Cr oxide...Pb or 1]b
Superconductor layer 13 made of alloy b+, < is Nb...Mask layer Applicant Nippon Telegraph and Telephone Corporation Figure 1A Figure 1B Figure 3Figure 8Figure 3 Figure 8 Figure 8 Figure 3

Claims (1)

[Claims] 1. Ai, Cr, 15JIIt compound or Or
A first superconductor electrode made of N11 is formed with a pattern of concave portions on the right through a metal made of oxide or a metal oxide layer, and on the first superconductor electrode, A, l Through layers 1 to 7 of oxide or c + oxide, I)b is made of Pb alloy or Nb.
A second superconductor electrode is formed on the substrate, on which an insulating layer of silicon oxide is formed on the surface.
, forming a first metal or metal oxide layer of AM oxide or Or oxide;
forming a first superconductor layer of Forming a first superconductor electrode made of Nb with a new pattern from the superconductor layer, and forming a first superconductor electrode made of AM oxide or Or oxide on the first superconductor electrode. - forming a tunnel barrier layer, and forming a second superconductor electrode made of PB or P11 alloy or Nb on the tunnel barrier layer and facing the first superconductor electrode via the tunnel barrier layer; The tunnel-type device is characterized by including a process of forming it. 3. On the substrate on which the first insulating film made of silicon oxide is formed, deposits of AL, Cr, ALl oxide I or C
a step of forming a first metal or metal oxide layer made of R1L oxide; a step of forming a first superconductor layer made of N1 on the first metal or metal oxide layer; C1-4 gas or CB for the first superconductor layer
A first superconductor layer 4 made of Nb having a desired pattern is formed from the first superconductor layer between the edges by a reactive sputtering process using rF+ gas. A second layer of silicon oxide 'C is applied to the area where the first superconductor electrode is not formed on the rod and the F closed substrate plate so as to fill the first superconductor electrode from the side. between the first superconductor electrode and the second insulating layer, consisting of an AL oxide or a Cr1lQ compound extending continuously through them; 1] 1) or a Pb alloy 1 on the tunnel barrier layer.
．． +1. < is 1 to form the second superconductor layer made of Nb.
Cheng and Sat iS [! CF to the second superconductor layer is removed from the second superconductor layer by a reactive bath/lid treatment using car F+ gas. A desired pattern facing the first superconductor electrode is formed through a barrier layer to form a second superconductor electrode made of PL+ or Pb alloy or Nll. This is a manufacturing method for tunnel-type Jollefson elements.