High-tc-super conductor oxide ceramic product and macroscopic view and microcosmic manufacture method
The present invention relates to high-critical temperature (Tc) superconduction oxide ceramic product, and macroscopic view and the microscopic approach of making this high Tc superconduction oxide ceramic product.The critical current density height of the present invention's high Tc superconduction oxide ceramic product, the critical magnetic field height, the life-span is long, can recharge or make simultaneously superconductivity regeneration.
Since since finding the superconductivity of high Tc first aspect the burning ceramics, existing many people attempt to find out the basic physics root of this superconductivity.What It is generally accepted is the copper dioxide CuO of high Tc superconductor
2The microstructure on plane is playing key effect aspect the high Tc superconductivity.On two dimension, in the high Tc burning superconductivity ceramics, all round four oxygen atoms (if from three dimensions, six oxygen atoms then being arranged around a copper atom), each copper atom can provide three electronics to its arest neighbors at the most simultaneously around each copper atom.Do not have stable covalent bond between this expression copper atom and the oxygen atom.Therefore, the copper electronics is faint localization, can cross oxo bridge and finishes quantum tunneling (tunneling) effect.This collective quantum tunneling effect is playing key effect aspect the high Tc superconductivity.Owing to the exchange interaction between two copper ions is done intermediary by oxonium ion, so the extra spin in that aperture of localization on oxygen will have great role.If the spin of two copper ions is appointed as
, And is appointed as oxonium ion
The time, then
To be tending towards with
The two keeping parallelism or antiparallel.Therefore, the spin of high Tc superconductor is very unordered.Because the mixed valence synchronous vibration, the localization spin wave function for symmetry or antisymmetric simultaneously can be along with the time changes rapidly.Unordered spin wave function will be adjusted automatically, so that follow tunneling electron.
The present invention relates to utilize the burning pottery to make the new method of the high Tc superconductive products of sealing fully, and the high Tc superconductive products of complete sealed type that utilizes these methods to make.Method of the present invention and product be based on following understanding, that is the oxygen content of metal oxide is at high Tc superconductor and contain in the product of this content and play an important role.If subcritical oxygen content X
C1(O) or be higher than critical dissolved oxygen content X
C2(O), superconductivity promptly can be destroyed.Between these two critical concentrations, critical temperature Tc changes to some extent.With YBa
2Cu
3O
XThis superconducting oxide system is an example, its critical dissolved oxygen content X
C1And X (O)=6.5,
C2(O)=7.0.Experiment shows, if oxygen atom is overflowed from high Tc superconductor, and when making oxygen content be reduced to subcritical oxygen content X, the superconductivity of metal oxide is promptly destroyed.If increase oxygen content, for example in predetermined temperature range under oxygen containing condition the metal oxide ceramic of sintering anoxic, can recover its superconductivity.With regard to YB
A2Cu
3O
X, bare bones is its oxygen content X(O) and must satisfy following formula 6.5<X(O)<7.0, and with regard to all high Tc oxide superconductors, its oxygen content must coincidence formula X
C1<X(O)<X
C2
The high Tc superconductivity state of oxide ceramic only is a kind of metastable state, the insulator that becomes a kind of stable state so the superconduction oxide ceramic is easy to lose oxygen.The process of this oxygen loss may be several hours, several days, some months or more than several years, the environmental condition that this depends on around the superconducting oxide comprises temperature and atmosphere or the like.Yet no matter the process of oxygen loss may be how long, metastable superconducting state is easy to become the trend of stable insulation state and can affirms.Therefore, be the high Tc superconductivity of protection oxide ceramic, this pottery just must be kept the oxygen content that meets superconducting state.
The invention provides a kind of fully closed superconductive products, in case block loss and obtain a kind of high Tc superconduction oxide ceramic product of longevity.As described in detail later, sealer available metal, plastics or anyly keep the material of inertia to make to oxygen.
Also based on following understanding, promptly high Tc superconductor belongs to ceramic material in the present invention, and the fundamental property of this material is exactly a fragility.Because ceramic superconductor has this frangible characteristic,, make superconductive products with the electric wire, cable and the band that contain superconductivity ceramics again so once there were many people to attempt to utilize the conventional method of making electric wire, cable and band to make high Tc superconductivity ceramics product.The method that this class is made electric wire, cable and the band of superconductivity ceramics product includes: the 4th, 952, No. 554 United States Patent (USP)s; The 4th, 965, No. 249 United States Patent (USP)s; The 4th, 975, No. 416 United States Patent (USP)s; With the 4th, 973, No. 574 United States Patent (USP)s.Make the method for superconductivity ceramics product as for some other, then in following United States Patent (USP), openly come out; The 4th, 975, No. 411 United States Patent (USP)s; The 4th, 975, No. 412 United States Patent (USP)s; The 4th, 974, No. 113 United States Patent (USP)s; The 4th, 970, No. 483 United States Patent (USP)s; The 4th, 968, No. 662 United States Patent (USP)s; The 4th, 957, No. 901 United States Patent (USP)s, the 4th, 975, No. 414 United States Patent (USP)s; And the 4th, 939, No. 121 United States Patent (USP)s.
Yet the conventional manufacture method of all these high Tc superconduction oxide ceramic products all more or less has its shortcoming.The method of making electric wire and cable generally includes the drawing or the procedure of processing of the diameter that reduces superconduction oxide ceramic product together.This drawing and procedure of processing are easy to make frangible oxide ceramic product fracture, cause the cycle period of fracture and sintering to repeat again and again, and made electric wire then lacks pliability and continuity because of fracture.In addition, the conventional method of making the superconductivity ceramics product also fails to realize the high mass density that high current density is required always, and superconduction sectional area and non-superconducting sectional area is lower simultaneously, thereby suffers bad oxygen loss, causes superconductivity to be lost.Moreover the conventional manufacture method of high Tc superconduction oxide ceramic product is because relate to expensive material and a lot of time-consuming procedure of processing, so cost is very high, can only the limited several prods of production shape, and to be used for limited application purpose.In addition, existing method can not or inconvenience produce high Tc superconducting connector, this connector is necessary especially when making the Tc superconducting magnet.Make the key technology of high Tc superconducting magnet, just be the manufacturing of zero resistance connector.
The present invention also attempts to utilize a kind of alternation or selects the pulsed magnetic field of waveform to remove to destroy magnetic moment order (this is unfavorable to high Tc superconductivity), makes oxygen at CuO
2The , And that quickens on the face to plant oneself during heating treatment utilizes the dynamic process of alternating magnetic field to make CuO
2Mask has desirable orientation.Compare with static magnetic field, the present invention uses the efficient of dynamic magnetic field higher.Its reason is
(t), wherein
Be the magnetization, and
(t) then be alternating magnetic field.This dynamically very important, so alternating magnetic field will make magnetic moment rotation at random rapidly, and, can make oxygen on the copper dioxide plane, quicken the condition that plants oneself so create because of alternating magnetic field localized magnetization order can stop the diffusion of oxygen.Therefore, the application alternating magnetic field is much better than and applies static magnetic field.
The present invention relates to high Tc superconduction oxide ceramic product, and macroscopic view and the microscopic approach of making this product.In order to the superconduction oxide ceramic of the superconductive products of making the present invention, can be any superconduction oxide ceramic (the oxide series that comprises aluminium), for example REB
A2Cu
3O
9-δPottery, wherein RE is one or more rare earth elements that are selected from a group that yttrium (Y), lanthanum (La), europium (Eu), lutetium (Lu) and scandium (Sc) constitute, the scope of δ is usually between 1.5 to 2.5.A kind of specific oxide ceramic that is used for product of the present invention is YBa
2Cu
3O
X, wherein X is between 6.5 and 7.0.
The degree that the manufacture method of high Tc superconduction oxide ceramic product of the present invention makes the oxygen loss minimize or to prevent substantially, the while can keep the superconducting characteristic of oxide ceramic product very long, even the unlimited time.A kind of method of the high Tc superconduction of manufacturing according to the present invention oxide ceramic product is the macro approach that a kind of complete closed ground produces high Tc superconduction oxide ceramic product.The step that this macro approach comprised is as follows: make superconduction oxide ceramic powder; Ducted body with a kind of material of not following the oxygen reaction is provided; With at least 5 * 10
4Psi to 1 * 10
7The fine pressure of psi is pressed into superconduction oxide ceramic powder in the ducted body by force, but with regard to YBa
2Cu
3O
X, fine pressure is by force preferably 1.2 * 10
5Psi above (pressure is decided on material and shape); According to the sintering that is enough to the sintering oxidation ceramic powder, annealing and chilling temperature and time, in oxygen atmosphere, ducted body and the superconduction oxide ceramic powder that is pressed in it are heat-treated; During sintering and follow-up heat treatment, can select to use waveform or multipulse alternating magnetic field (from 0.0001 tesla to 300 teslas), dynamically to destroy local magnetic moment, and dynamically impel the oxygen And that on the copper dioxide plane, quickens to plant oneself dynamically to make microcosmic copper dioxide plane have desirable orientation of bearing high critical current and upper critical magnetic field, wherein the intensity in added magnetic field becomes with the shape of material and product; Seal up two ends and/or this ducted body other any openings that may form before sintering of ducted body then.Also available local heat treatmet is made between the high Tc superconductive products or the coupling part between certain product and the superconductor line.If superconduction oxide ceramic product is complex-shaped, promptly must engage the coupling part between each ducted body that is pressed into superconduction oxide ceramic powder in it earlier, and then carry out second the step be pressed into step, before sintering, all fill up the superconductivity ceramics powder continuously to guarantee all coupling parts, do not stay any gap.
Totally-enclosed high Tc superconduction oxide ceramic product with macro approach made of the present invention, its shape and size can be followed one's bent, be suitable for use as high Tc superconducting magnet simultaneously, high Tc superconducting motor, high Tc superconducting generator, high Tc superconducting transmission line, high Tc superconductive power storing apparatus or its parts And and, in general, needing can be used for any purpose of superconductor.
The microcosmic manufacture method of high Tc superconduction oxide ceramic product of the present invention also is based on isolated (i.e. " sealing ") superconduction oxide ceramic component, thereby in case oxygen loss or diffusion cause the forfeiture of superconductivity.The microcosmic manufacture method of high Tc superconduction oxide ceramic product of the present invention comprises the steps: to utilize electron beam deposition, molecular beam deposition, sputtering deposit, the any suitable mode of laser ablation or other on the spot make on the substrate floor height Tc superconduction ceramic oxide thin film (making on the spot film during, can apply alternating magnetic field selectively); Then where necessary, the film that in a certain magnetic field, goes out selectively with the deposit of oxygen atmosphere sintering; And and utilize scanning-tunnelling electronic processor (STETM) from a certain microcosmic farmland of superconduction ceramic oxide thin film (for example 5

To 1000
) in remove the oxygen content of part so that between two high Tc superconduction farmlands that form the Josephson knot, form a microcosmic insulating barrier.Use the present invention's the made high Tc superconductive products of microscopic approach to be particularly suitable for as superconduction chip, high Tc superconducting circuit, SQUIDS and assembly thereof.
Therefore, the present invention's purpose is to provide a kind of high-tc-super conductor oxide ceramic product that does not have those shortcomings that existing superconductivity ceramics product manifested.
A further object of the present invention is that scanning tunnel microscope is modified into STETM, that is makes electronic processor into from microscope, so that utilize the localization electric current to make required microscopic pattern, this not only can be used to produce high Tc superconductive products, can also be used for semi-conductor industry.
Another object of the present invention provides enclosed high Tc superconduction oxide ceramic product, in case the forfeiture of the loss of oxygen and superconductivity.
Another purpose of the present invention provides a kind of macro approach of making high Tc superconduction oxide ceramic product, and this method does not need conventional drawing and such electric wire and the cables manufacturing technology of cold working.
A further object of the present invention provides a kind of macro approach that can make the high Tc superconduction oxide ceramic product of shape of all kinds, size and structure.
Another object of the present invention provides the high Tc superconduction of a kind of manufacturing oxide ceramic product, thus the method that high Tc superconduction oxide ceramic constituent all is protected aspect mechanical, electric and chemical.
Another purpose of the present invention provides the both macro and micro method of the high Tc superconduction oxide ceramic product of making high-quality and growing service life.
A further object of the present invention provides a kind of microscopic approach of making high Tc superconduction oxide ceramic product.
Another purpose of the present invention provides a kind of device and method that can form microcosmic insulating barrier or farmland in the superconduction ceramic oxide thin film.
Another object of the present invention provides a kind of method that is used to make the coupling part between high Tc superconduction oxide ceramic product.
Another purpose of the present invention provides a kind of method of producing superconductive products, this method is during heating treatment used alternating magnetic field, so that dynamically destroy magnetic moment, make the oxygen , And that on the copper dioxide plane, quickens to plant oneself make the copper dioxide plane by required direction orientation.
Explanation in conjunction with the drawings, these and other objects of the present invention can further be understood.Wherein:
Fig. 1 is the profile of closed high Tc superconduction oxide ceramic product first embodiment that produces with macro approach of the present invention;
Fig. 2 is the profile of closed high Tc superconduction oxide ceramic product (high-tc-super conductor magnet) second embodiment that produces with macro approach of the present invention;
Fig. 3 is the sectional exploded view of the parts of superconductive products shown in Figure 2 (high Tc superconducting magnet);
Fig. 4 is the profile of closed high Tc superconduction oxide ceramic product the 3rd embodiment that produces with macro approach of the present invention;
Fig. 5 is the profile along V among Fig. 4-sealing coupling part that the V line is got;
Fig. 6 a, 6b and 6c are the profile with difform high Tc superconduction oxide ceramic product embodiments of the present invention;
Fig. 7 is and the similar profile of Fig. 1 to demonstrate different sealing coupling parts, end;
Fig. 8 a and 8b are respectively the schematic diagram that in an alternating magnetic field the macroscopical product and the film of high Tc superconduction oxide ceramic is carried out sintering according to both macro and micro method of the present invention;
Fig. 9,10 and 11 are used various improved scanning-tunnelling machine (to call scanning-tunnelling electronic processor (STETMS) in the following text) schematic diagram of microscopic approach of the present invention;
The generalized section of the high Tc superconduction oxide ceramic membrane with low oxygen content insulation farmland that provides with microscopic approach of the present invention is provided Figure 12;
Figure 13 is the schematic diagram of the SQUID that produces with microscopic approach of the present invention;
Figure 14 is the schematic diagram of a kind of integrated circuit of producing with microscopic approach of the present invention; And
Figure 15 contains the schematic diagram of the ducted body of ceramic powder for the shell that carries out pressurized treatments according to the present invention.
Now consult accompanying drawing, Fig. 1-7 especially wherein demonstrates some embodiment of the high Tc superconduction of complete closed formula of the present invention oxide ceramic product.These embodiment make with macro approach of the present invention entirely.Adopt macro approach described later, can produce the complete closed formula superconductive products shown in Fig. 1-7.
At first, utilize the powder metallurgy technology of standard, each compound or the composition of making high Tc superconduction oxide ceramic constituent are mixed with powder-form.For example, highly purified yittrium oxide (Y
2O
3), brium carbonate (BaCO
3) and cupric oxide (CuO) powder mix in water-free mode, to make required high Tc superconducting compound YBa
2Cu
3O
XThen in the porous ceramics crucible in draughty baking box, the powder that mixes is heated to 940 ℃ temperature, passed through about 12 hours, cool off again about 3 hours.Mixture of powders is about in temperature under 450 ℃ the condition kept 3 hours, then slowly be cooled to room temperature again.After the mixture of powders that so obtains pulverized and mixing, repeated same program again 8 to 12 hours, oxygen is flow through in baking box.Can produce the superconduction black powder of high Tc with this program, and then this powder is carried out for the third time grinding.
Then this superconductive powder is followed these steps to be used for macro approach of the present invention.Earlier superconductive powder is pressed into any not with the made pipe or preforming mould of the suitable material of oxygen reaction in.Pipe or preforming mould can be with not making with the metal or the plastics of oxygen reaction.Suitably examples of material has stainless steel and inwall to scribble the stainless steel tube that oxygen is kept the coating of inertia.Will be greater than about 5 * 10
4The fine pressure of psi is applied to by force on the superconductive powder, guarantees that this powder by in complete ascending pipe or the prefabricated component, does not stay any space.Should select the pressure that applies, so that the powder filler compacting reaches desirable density.For example, if want to allow YBa
2Cu
3O
XPowder reaches density and is about 5.0 gram/Cm
3, must apply 1.2 * 10
5The pressure of psi.It is strong to utilize punching machine, hydraulic press and high pressure 895 forcing presses can reach this fine pressure, can use any high pressure technique simultaneously.Strong for guaranteeing required high fine pressure, should surround the pipe of powder filler with the solid metal substrate, for example shown in Figure 15 around substrate 200, it is very similar with the solid metal model of casting.Insert after the superconductive powder Deng within pipe or the preforming mould, under the situation that its two end is held open according to the following step sintering in addition.Pipe or the preforming mould of filling in powder were heated in baking box or smelting furnace about 3 hours, make it be heated to 940 ℃, and then kept about 6 hours being about under 940 ℃ the condition from room temperature.Then begin to allow Oxygen Flow cross baking box or stove, make sample be cooled to 550 ℃ temperature in the time about 10 hours gradually, again when keeping Oxygen Flow, cooled off again 10 hours, to about 200 ℃ temperature, and then with Oxygen Flow temperature slowly is cooled to the room temperature degree with about 10 hours time again.If preforming mould is complex-shaped, rather than simple pipe, then except openend, still perforate mouth in addition can flow through entire product to guarantee Oxygen Flow.By the time after sintering is finished, again with these aperture sealings.
The zero resistance and Mai Sina (Meissner) effect of the product that the test sintering obtains.If after confirming its superconductivity, sealed at both ends the living in case the oxygen loss that is about to pipe or preforming mould, thus finish the production of the present invention's the high Tc superconduction of complete closed formula oxide ceramic product.
More specifically consult accompanying drawing, the high Tc superconductive products 10 of complete closed formula wherein shown in Figure 1 is produced with following process.Earlier with superconduction oxide ceramic powder 12 with 1.2 * 10
5In the pressure ascending pipe 14 more than the psi; Then utilize the oxygen sintering pipe of powder filler as previously mentioned, the flow velocity of oxygen is preferably in 1 more than the atmospheric pressure; Use end seal thing 16,18 to seal the openend of the pipe 14 of sintered products then, to reach the effect of complete closed.Shown in Fig. 8 a, during heat treated, can use a kind of alternating magnetic field.Before pipe 12 two ends are sealed, earlier by aforementioned such high Tc superconducting property of verifying or measuring product.The all any known ways that can guarantee to reach the fluid seal effect, for example welding or with the end cap of thread seal all can be used as end seal thing 16,18.The section configuration of pipe 14 can be followed one's bent, and as circular, rectangle or square, decides on the final use of superconductive products.In oxygen or air ambient, can be in the superconduction coupling part between use localized heating under certain pressure condition is made superconductive products or gone between, as for the then available electric heating of mode of heating or other any localized heating method.
It is a kind of for producing different shape that macro approach of the present invention also provides, and comprises the straightforward procedure of the high Tc superconduction oxide ceramic product of those complicated and compound shapes shown in Fig. 2-6c.Fig. 2 and 3 is respectively made a kind of high Tc superconducting magnet and parts thereof according to the present invention.High Tc superconducting magnet as shown in Figure 2 provides a complete continuous superconducting ring that does not stay any welding, welding or pressing seam after making.When producing superconducting magnet 20 as shown in Figure 2, prepare two metal tubes 22 that do not react with oxygen earlier, 24-preferably stainless steel , And will manage 22 be wound into suitable spiral-shaped.Then, high Tc superconduction oxide ceramic material 26 usefulness 1.2 * 10 of powder-form
5The above pressure of psi is pressed among each metal tube 22,24.It should be understood that metal tube is done into required form can reverse with the step that is pressed into powder.That is to say, at least earlier a part of high Tc superconduction oxide ceramic powder is pressed into after the metal tube, again it is done into required form.By the time high Tc superconduction oxide ceramic powder is pressed into after each metal tube 22,24, just will manage 22,24 and be assembled according to shown in Figure 3, makes it form the superconducting magnet 20 of required complex form.Utilize any suitable mode,, metal tube 24 is connected on the metal tube 22 as welding or other any Pipe joining method.
Connect after the appropriate metal tube 22,24, reuse the above pressure (5 * 10 of 50K psi
4Psi<P<1 * 10
7Psi) powder is pressed into, makes the continuous connection of the whole tubular structure formation of product, thereby the gap can not take place between guaranteeing to manage 22 and 24, in order to avoid the anxiety of aerobic loss without any the gap.This step that is pressed into superconduction oxide ceramic powder is once more guaranteed parts, and just metal tube 22,24 engages the whole junction surface that forms final form, all belongs to continuously connecting.
Then, insert the preforming mould of superconductive powder in it according to aforementioned manner sintering under the oxygen environment.If belong to the superconducting magnet of the sort of complicated shape as shown in Figure 2, be preferably in and open several apertures or window on the metal tube 22,24, guarantee that oxygen can flow through whole body.After having verified the high Tc superconducting property of sintered products, just seal aperture or window , And again and use end cap 28,29 to seal up two ends of metal tube 22 fully, this product is sealed fully.
Now see also Figure 4 and 5, wherein demonstrate two with similar sintered products shown in Figure 1, engage or link together and make a kind of superconduction oxide ceramic product in the opposite end mode.Especially as can be seen from Figure 4, two respectively have a sintered products that is pressed into the pipe 32 of sintering superconduction oxide ceramic powder 34 in it and are bonded with each other with connector 38, and Guan Yiduan seals with end cap 36.As shown in Figure 5, connector 38 surrounds pipe 32 abutting end , And and with screw 39 connector is fixed together.Perhaps, except that screw 39, can on connector 38, establish internal thread , And and establish screw thread in pipe 32 end 40, thereby the termination 40 of metal tube 32 can be screwed in the connector 38 to match.
Fig. 6 a, 6b and 6c those shown are the sintered products according to other made shape of the aforementioned macro approach of the present invention, and wherein the high Tc superconduction oxide ceramic product 50 of Fig. 6 a comprises a pipe 52, is pressed into sintering superconduction oxide ceramic powder 54 in this pipe, manage 52 two ends simultaneously and be provided with end cap 56,58.This superconduction oxide ceramic product 50 is made with aforesaid macro approach.When making this product, can in pipe 52, be pressed into powder 54 before or after, pipe 52 is curved 90 angles of spending.High Tc superconduction oxide ceramic product 60 shown in Fig. 8 b is a T shape structure, and it extremely is suitable for superconductive products and makes T shape coupling part.T shape superconduction oxide ceramic product 60 shown in Fig. 6 b is by metal tube 62, sintering superconduction oxide ceramic 64 and end cap 66,67 and 68 formations.According to the mode shown in Fig. 2 and 3, with the pipe (as metal tube) of a T shape, or two straight tubes are bonded together, thereby form a T shape structure, promptly can be made into this T shape superconductive products 60.
At last, Fig. 6 c is depicted as the made a kind of complete sealed type four-way superconducting connector of macro approach with the present invention.This four-way connector 70 is by pipe 72, sintering superconduction oxide ceramic 74 and end cap 76,77,78 and 79 formations.With a four-way pipe, or two pipes are bonded on relative two ends of a pipe fitting toward each other from inter-engagement or essence, thereby form a continuous superconduction four-way connector, promptly can be made into this four-way superconducting connector 70.
Now see also Fig. 7, wherein show the another kind of method that the two ends to the pipe that includes the high Tc superconduction of sintering oxide ceramic are sealed.Superconductive products 80 shown in Figure 7 is made of a pipe 82, sintering superconduction oxide ceramic 84, end cap 86 and end envelope apparatus 88.First end 90 of pipe 82 is provided with the internal thread that matches with end cap 86, and this end cap is a female connection device.The other end 92 of pipe 82 also is provided with internal thread, can match with female connection device 88.
Though used some different embodiment to describe in detail, it should be understood that shape, structure and the seal arrangement that also can comprise other within the scope of the invention with the made high Tc superconduction oxide ceramic product of macro approach of the present invention.In addition, the macro approach before being specified in also can be revised where necessary, so that make it be adapted to the manufacturing of undocumented other superconduction oxide ceramic product here.Moreover, may also need other procedure of processing and aforesaid macroscopical mode are merged use.For example, the sintering of superconduction oxide ceramic powder can be shown in Fig. 8 a, at alternating magnetic field (10
-4Tesla is to 300 teslas) in carry out, guarantee high current density.In addition, the present invention's superconduction oxide ceramic product is after through long-term the use, and available oxygen is sintering and resealing again, so that can reuse one long-term period.
Now see also Fig. 8 b-14, wherein microscopic approach of the present invention will be described, and with the made superconduction oxide ceramic product of the method.This microscopic approach comprises the steps: to utilize known deposition technology, for example electron beam deposition, sputtering deposit, molecular beam deposition, laser ablation or other any suitable mode, form a floor height Tc superconduction oxide ceramic compound film; And is during film forming on the spot, or during the sintering of film after forming, can apply a certain alternating magnetic field selectively, so that improve the quality of film; Utilize a certain microcosmic farmland of scanning-tunnelling electronic processor (STETM) the heating superconduction ceramic oxide thin film of improvement, so that from this microcosmic farmland, remove partial oxygen content.Before scanning-tunnelling electronic processor (STETM) is handled, must remove originally film forming dielectric substrate earlier thereon, then by high Tc film support itself, or be coated with one deck and support electrically-conducting paint.After the processing, must live elastic membrane sealing, make it stable with protection Yang Han Liang And with the suitable seal layer.Potential barrier will be protected the isolation on hypoxemia farmland and hyperoxia farmland.If used thin conductive substrates when making film, so will its removal before the scanning-tunnelling electronic processor is handled.
The film of deposit can be superconduction, perhaps, can with the similar condition of above-mentioned macro approach under sintered film so that make high Tc superconducting film.Described sintering is preferably in the alternating magnetic field shown in Fig. 8 b and takes place.The necessary characteristic in magnetic field is exactly that scope is 10
-4Tesla is to the alternating magnetic field waveform between 300 teslas.If on a substrate, then substrate can have any suitable size thin film deposition, for example thickness is from 10
-6M is to 1Cm.Except that cupric oxide (CuO) series, substrate can be other any oxide material.For example aluminium oxide (AIO) or magnesium oxide (MgO) series.The thickness of film is usually about 30
Between 10 μ m, but preferably 100
To 1000
Between.
For implementing the used scanning-tunnelling electronic processor of microscopic approach of the present invention, be improved scanning-tunnelling machine.It has two tips respect to one another as shown in Figures 9 and 10, or has two blocks of relative plates, and each piece all is provided with some tips relatively as shown in figure 10.Interchange or direct current pass through between relative tip, so that the localized heating size is 5
To 1000
Between the microcosmic farmland.In the present invention, film is placed between the plate at two tips or two band tips.When two tips during, flow through most advanced and sophisticated interchange or direct current and fail to be convened for lack of a quorum and aim at about 5 to 20 near film
2Local farmland, film is carried out localized heating, thus the local as required oxygen content of removing.Relative tip can be moved independently of one another or together, and the program by the control shift action decides entirely.Though Fig. 9-11 is depicted as DC current source, also should be understood that and to use ac current source instead.Electric current can be about 10
-6Ampere is decided according to the type and the thickness of film and support (conduction) substrate between 100 amperes.In argon atmospher, the microcosmic farmland is heated between about 200 ℃ to 900 ℃,, and then forms microcosmic insulation farmland so that remove the oxygen content on this microcosmic farmland.
Microscopic approach of the present invention can form one or more sizes separately greatly about 5 in the superconduction ceramic oxide thin film
To 1000
Between microcosmic insulation farmland.Microcosmic insulating barrier between each high Tc superconduction farmland or farmland have formed can be for the Josephson knot of SQUIDS or any high Tc superconducting circuit use.With 5000 in the semiconductor
Insulated part is compared, and can be three-dimensional (3D) circuit by the made high Tc superconduction microscopic circuits of the present invention and saves 10
2* 10
2* 10
2Space doubly, and be that two dimension (2D) circuit saves 10
4Space doubly.
After handling with the scanning-tunnelling electronic processor, the microcosmic insulating barrier promptly is in stable state, and the superconduction farmland of adjacency then is in metastable state, thereby sets up the potential barrier of an oxygen molecule between two kinds of states.Be coated with last layer suitable seal layer then on the microcosmic film, sealant for example shown in Figure 12 is the microcosmic film complete closed that contains superconduction and insulation farmland.By the time will go between be connected on the membrane structure as required after, whole film all is sealed except going between.Therefore, the film that contains superconduction and non-superconducting farmland will be sealed by the coating sealant.By the isolation on this seal protection oxygen content and farmland, thereby prolonged the life-span.Because oxygen content needs activation energy to begin to be diffused in the insulation farmland, this has just formed the potential barrier of separating superconduction and insulation farmland, so the oxygen content in the superconduction farmland is had nowhere to go.As a result, the high Tc superconduction of sealed type chip just shows long characteristic service life.Liquid helium or low noise refrigeration then can be guaranteed the work of high Tc superconducting circuit.
Now see also Fig. 8 b, wherein demonstrate the situation of in alternating magnetic field, the superconduction oxide ceramic being carried out sintering.Film 100 is sintering under the oxygen atmosphere in stove 102, and oxygen flows in the stoves 102 via conduit 104.Utilize magnetic helix tube 106 to apply alternating magnetic field towards the B direction.
Fig. 9 illustrates schematically how microscopic approach of the present invention utilizes the scanning-tunnelling electronic processor to handle superconduction ceramic oxide thin film 110.
Film 110 usefulness supports 112 support, and make
film 110 vertical substantially with the point pin 114,116 of scanning-tunnelling electronic processor.Point pin 114,116 joins with current source 118, and its Tipping Center
pin 114 has negative potential, and
point pin 116 has the ac potential of positive potential or alternation.Point pin 114,116 each keep vertical mutually by three or quadrature and respectively towards X, the piezoelectric bar 120 that Y and Z direction are extended is supported.These sharp pins can optionally move it separately or relatively with procedure operation.Electric current can be 10
-6Between 100 amperes.Voltage can be 10
-3V to 10
4Between the V, decide according to material, thickness and other condition or the like.With the processing that a pair of pin of point is relatively carried out, can localization to 5
2Or littler degree, and if handle with the relative plate that respectively has some point pins, but then localization arrives greatly to 1 μ m
2Degree.The manufactured materials of point pin and plate can be to be made by tungsten, platinum, gold or its alloy and other material that is suitable for.
Figure 10 has shown schematically how electronics 122 flows to positive potential point pin 116 from the sharp pin 114 of negative potential via superconducting thin film 110, so that remove oxygen content and the situation that forms microcosmic insulation farmland.Figure 11 shows that the another kind of embodiment of scanning-tunnelling electronic processor, wherein be provided with some relative positive potential point pins 126 and negative potential point pin 124, on superconduction oxide film 128, forming several microcosmic insulation farmlands simultaneously.
Figure 12 shows that with the made a kind of superconduction ceramic oxide thin film 130 of microscopic approach of the present invention.This superconduction ceramic oxide thin film 130 contains several microcosmic insulation farmlands 132 between the high Tc superconduction farmland 134 of adjacency.Then be provided with sealant 136 one around the superconduction ceramic oxide thin film,, protect the isolation between superconduction and the non-superconducting farmland simultaneously in case the oxygen loss takes place on the superconduction farmland, and can prevent the forfeiture of consequent superconductivity.Since potential barrier be sealing and separated zone around it, so can not provide activation energy to go to overcome potential barrier, thereby the service life of superconductivity circuit is very long.This confining bed is a coatings layer a kind of and oxygen maintenance inertia, and available any suitable mode is used, and for example sprays, applies, floods or the like mode.137 is the lead-in wire coupling part.
At last, Figure 13 and 14 is depicted as a SQUID 150 and integrated
circuit 160 of making respectively with microscopic approach of the present invention.Say clearlyer, Figure 13 shows the SQUID 150 with a high Tc
superconducting ring 152 and Josephson
knot 154, and
knot 154 utilizes microcosmic insulation farmland to form, and can be as small as 5
-20
Degree (that is near copper dioxide CuO
2On the plane about 5
Coherence length).About microscopic approach of the present invention, be outside its uniqueness to make small but excellent true high-performance SQUID.The SQUID of Figure 13 is made by high-quality high Tc superconducting film.This film is placed the scanning-tunnelling electronic processor, and a superconducting ring is masked firmly.Utilize the scanning-tunnelling electronic processor to go to handle all the other positions of film then, form insulation layer or farmland to remove oxygen content.Then handle in the desirable zone of remaining superconducting ring with the scanning-tunnelling electronic processor again, so that make a Josephson knot.Make lead-in
wire coupling part 170 subsequently, and close the whole membrane structure except the lead-in wire coupling part.
Figure 14 shows that one comprises the integrated circuit 160 on some insulating barriers or farmland 162 and high Tc superconduction farmland 164.Use with the scanning-tunnelling electronic processor and handle the similar mode of high Tc superconducting film, make the required pattern on insulation farmland 164 and superconduction farmland 162 for integrated circuit 160; Then lead-in wire coupling part 174 is received on the structure that is produced, then the total except the lead-in wire coupling part is sealed up.
Aforementioned each embodiment is only in order to explanation the present invention, and is non-in order to limit the scope of the invention.To those skilled in the art, not breaking away under the described scope situation of spirit of the present invention and claims, all is conspicuous to the structure of the invention described above and the various revisions of method.