Patent Application
20060054882
The present invention relates to a switching element comprising an organic bistable material, the organic bistable material being arranged between two electrodes, which is utilized for a switching element driving of an organic EL display panel, a high-density memory, and the like.
In recent years, remarkable progress in characteristics of organic electronic materials has been made. Particularly, since some of low-dimensional conductors, such as charge-transfer complexes, have distinctive properties of being a material such as that with metal-insulator transition, attempts for the applications of them to a switching element driving of an organic EL display panel, a high-density memory, and the like, have been in progress.
As a material applicable to a switching element, an organic bistable material is being paid attention to. The organic bistable material is an organic material that shows a so-called nonlinear response. Namely, when a voltage is applied to the material, at a certain voltage or higher during the application of voltage, a switching phenomenon is observed where the current in a circuit is rapidly increased.
As shown in
As such organic bistable material showing the nonlinear response, various types of organic complexes are known. For example, R. S. Potember et al. manufactured as a trial experiment a switching element having two stable states in resistance against voltage, using a Cu-TCNQ (copper-tetracyanoquinodimethane) complex (R. S. Potember et al., Appl. Phys. Lett. 34, (1979) 405).
Further, Kumai et al. observed a switching behavior by a nonlinear response, using a single crystal of a K-TCNQ (potassium-tetracyanoquinodimethane) complex (Kumai et al., Solid-state Physics, 35 (2000) 35).
Further, Adachi et al prepared a thin film of Cu-TCNQ complex by a use of a vapor deposition method and confirmed its switching properties, further evaluating the possibility of its application to an organic EL matrix (Adachi et al, preparatory text of Japan Society of Applied Physics, spring of 2002, the third volume, 1236).
Furthermore, L. Ma et al studied that the above organic bistability can be performed even with a one-component material, using an organic material such as an aminoimidazole dicarbonitrile (AIDCN) material or an imine type material (L. Ma et al, Appl. Phys. Lett. 80 (2002) 2997; L. Ma et al, Appl. Phys. Lett. 73 (1998) 850; pamphlet of International Publication No. 02/37500).
However, switching elements using the above organic charge-transfer complexes have the following problems.
Namely, the above-mentioned organic bistable material using a charge-transfer complex is a material with two-component system, being made of a combination of an electron-donating molecule or an electron-donating metal element and an electron-accepting molecule such as TCQN.
Accordingly, for preparation of the switching element, it was required to strictly control the compositional ratio of two components. Namely, in a charge-transfer complex of such two-component system, for example, as shown in
Accordingly, for example, in the above Cu-TCNQ complex, the difference in the compositional ratio of Cu and TCNQ results in the difference in crystallinity and electric properties of the material and causes varying quality of the characteristic of bistability. Particularly, when film formation is carried out by a vapor deposition method or the like, due to the difference in the vapor pressure between both components, it is difficult to form a uniform film of a large area. It is also the case due to the geometrical arrangement or the like, when independent sources for deposition are used in a co-deposition method.
Accordingly, it has been a problem that the above conventional organic bistable materials with two-component system is not straightforwardly applicable to mass-production of switching elements that exhibit unvarying characteristic of bistability and consistent quality.
Further, L. Ma et al. describes that, in order to attain the bistability in an organic material with one-component system, it is an essential to disperse electrically conductive fine particles in an organic film, therefore such organic material with one-component system also has a problem in the insufficient properties of being bistable material.
The present invention has been accomplished in view of the above problems of the conventional techniques, and it is an object of the present invention to provide a switching element suitable for mass production, where the compositional deviation of materials can be suppressed, uniform properties in the characteristic of bistability can be attained, and an organic bistable material by itself can exhibit sufficient bistability.
Namely, the present invention provides a switching element which comprises: an organic bistable material, the organic bistable material having two stable states in resistance under applied voltage; at least two electrodes, the electrodes being placed such that the organic bistable material is arranged between two of the electrodes, the switching element being characterized in that the organic bistable material consists essentially of a compound having an electron-donating functional group and an electron-accepting functional group in a molecule of said compound.
In the switching element of the present invention, since the organic bistable material is of a one-component system having an electron donating functional group and an electron-accepting functional group in one molecule, fluctuation of the compositional ratio at the time of production hardly occurs unlike the conventional two-component system organic bistable material, whereby it is possible to always obtain a constant bistable performance.
Further, when a thin film is formed by particularly a vacuum deposition method, etc., since no complicated techniques such as a co-deposition method are not used, uniform thin films of a large area can be produced with low costs.
In the present invention, the compound is preferably an aminoimidazole type compound of the following formula (A):
wherein each of X1 and X2 is CN or NO2, and each of R1, R2 and R3 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In the present invention, the compound is preferably a γ-pyridone type compound of the following formula (B):
wherein R4 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In the present invention, the compound is preferably an imine type compound of the following formula (C):
wherein X3 is CN or NO2, each of R5 and R6 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, and m is an integer of 1 to 5.
In the present invention, the compound is preferably an imine type compound of the following formula (D):
wherein X4 is CN or NO2, each of R7 and R8 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, and m is an integer of 1 to 5.
In the present invention, the compound is preferably a compound of the following formula (E):
wherein either one of Y1 and Y2 is a nitrogen atom, and another one thereof is a carbon atom which has as a substituent an amino group or a C1-6 alkylamino group.
In the present invention, the compound is preferably a compound of the following formula (F):
wherein each of R9 and R10 is a hydrogen atom or an alkyl group having at most 2 carbon atoms, and each of R11 and R12 is a hydrogen atom or an amino group.
In the present invention, the compound is preferably a compound of the following formula (G):
wherein each of R13, R14 and R15 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In the present invention, the compound is preferably an iminequinone type compound of the following formula (H):
wherein each of R16 and R17 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, and each of R18 and R19 is an aryl group which may have a substituent, a C1-6 alkyl group which may have a substituent, or a hydrogen atom, provided that at least one of R18 and R19 is an aryl group which may have a substituent.
In the present invention, the compound is preferably a quinoneimine compound of the following formula (I):
wherein each of R20 to R23 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In the present invention, the compound is preferably a dicyano type compound of the following formula (J):
wherein each of R24, R25 and R26 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, an aryl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, each of m and n is an integer of 1 to 5, and i is an integer of 1 to 4.
In the present invention, the compound is preferably a pyridone type compound of the following formula (K):
wherein each of R27, R28 and R29 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, or an aryl group which may have a substituent, R30 is a C1-6 alkyl group which may have a substituent, or a residual group which is capable of forming a ring, and i is an integer of 1 to 4.
In the present invention, the compound is preferably a pyridone type compound of the following formula (L):
wherein each of R31 and R32 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, R33 is a C1-6 alkyl group which may have a substituent, or a residual group which is capable of forming a ring, each of R34 and R35 is an aryl group which may have a substituent, or a hydrogen atom, provided that at least one of R34 and R35 is an aryl group which may have a substituent, and i is an integer of 1 to 4.
In the present invention, the compound is preferably a quinoneimine type compound of the following formula (M):
wherein each of R36 and R37 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, or an aryl group which may have a substituent, R38 is a C1-6 alkyl group which may have a substituent, an aryl group which may have a substituent, or a residual group which is capable of forming a ring, and m is an integer of 1 to 5.
In the present invention, the compound is preferably a quinoneimine type compound of the following formula (N):
wherein each of R39 and R40 is a hydrogen atom or a C1-6 alkyl group which may have a substituent; each of R41, R42 and R43 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, an aryl group, or a residual group which is capable of forming a ring; i is an integer of 1 to 4; and each of m and n is an integer of 1 to 5.
In the present invention, the compound is preferably a stilbene type compound of the following formula (O):
wherein each of R44, R45 and R46 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an amino group which may have a substituent, or an aryl group which may have a substituent; R47 is a hydrogen atom, a halogen atom, a nitro group, a cyano group or an aryl group which may have a substituent; each of m, n and o is an integer of 1 to 5; and i is an integer of 1 to 4.
In the present invention, the compound is preferably a butadiene type compound of the following formula (P):
wherein each of R48 and R49 is a hydrogen atom, a halogen atom, a nitro group, a cyano group or an aryl group which may have a substituent; each of R50 and R51 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an amino group which may have a substituent, or an aryl group which may have a substituent; and each of m, n, o and p is an integer of 1 to 5.
In the present invention, the compound is preferably a stilbene type compound of the following formula (Q):
wherein each of R52, R53, R54 and R55 is a hydrogen atom, a halogen atom, a nitro group, a cyano group, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an aryl group which may have a substituent, or a residual group forming a ring which may have a substituent; each of m and n is an integer of 1 to 5; i is an integer of 1 to 4; and q is an integer of 1 to 9.
In the present invention, the compound is preferably a triphenylamine type compound of the following formula (R):
wherein each of R56, R57, R58, R59 and R60 is a hydrogen atom, a halogen atom, a nitro group, a cyano group, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an aryl group which may have a substituent, or a residual group which is capable of forming a ring; each of m, n, o and p is an integer of 1 to 5; i is an integer of 1 to 4; and r is an integer of 1 to 2.
The above compounds of the formulas (A) to (R) are one-component system aromatic molecules having an electron donating functional group and an electron-accepting functional group in one molecule, and thus no fluctuation of the compositional ratio at the time of production cannot occur unlike the two-component system organic bistable materials.
Further, the above compounds of the formulas (A) to (R) are excellent in the bistability and can be easily formed into a thin film by a vapor deposition method, etc., whereby these are particularly preferably used as the organic bistable material.
Hereinbelow, the present invention will be described with reference to drawings.
As shown in
Although the substrate 10 is not particularly limited, conventionally known glass substrates or the like are preferably used.
As the electrode layers 21a and 21b, metal materials such as aluminum, gold, silver, nickel and iron, inorganic materials such as ITO and carbon, conjugate organic materials, organic materials such as liquid crystals, semiconductor materials such as silicon, etc. may appropriately be selected, and the electrode layers are not limited thereto.
Next, the present invention is characterized in that the organic bistable material to be used for the bistable material layer 30 consists essentially of a compound having an electron-donating functional group and an electron-accepting functional group in each molecule of the compound.
As the electron-donating functional group, —SCH3, —OCH3, —NH2, —NHCH3, —N(CH3)2, etc. may be mentioned. As the electron-accepting functional group, —CN, —NO2, —CHO, —COCH3, —COOC2H5, —COOH, —Br, —Cl, —I, —OH, —F, ═O, etc. may be mentioned.
Further, as the compound having an electron-donating functional group and an electron-accepting functional group in each molecule of the compound, an aminoimidazole type compound, a pyridone type compound, a styryl type compound, a stilbene type compound, a butadiene type compound, etc. may be mentioned.
Among the above compounds, in the present invention, it is preferred to use an aminoimidazole type compound of the following formula (A):
wherein each of X1 and X2 is CN or NO2, and each of R1, R2 and R3 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In the above compound, the CN group or the NO2 group acts as the electron-accepting functional group and the NH2 group, NHCH3 group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
Here, when the above R1, R2 or R3 is an alkyl group, it is preferably an alkyl group having at most 6 carbon atoms, more preferably an alkyl group having at most 2 carbon atoms. When it is an alkyl group having more than 7 carbon atoms, molecular alignment necessary for conductivity is likely to be restricted and sufficient bistability is hardly obtainable, such being undesirable.
As such aminoimidazole type compound, specifically, compounds of the following formulas (A-1) to (A-4) may, for example, be mentioned.
Further, it is also preferred to use a γ-pyridone type compound of the following formula (B):
wherein R4 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In the γ-pyridone type compound, the C═O group acts as the electron-accepting functional group and the N—R group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
Here, when R4is an alkyl group, it is preferably an alkyl group having at most 6 carbon atoms, more preferably an alkyl group having at most 2 carbon atoms. When it is an alkyl group having more than 7 carbon atoms, molecular alignment necessary for conductivity is likely to be restricted and sufficient bistability is hardly obtainable, such being undesirable.
As such γ-pyridone type compound, specifically, compounds of the following formulas (B-1) and (B-2) may, for example, be mentioned.
Further, it is also preferred to use an imine type compound of the following formula (C):
wherein X3 is CN or NO2, each of R5 and R6 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, and m is an integer of 1 to 5.
Further, it is also preferred to use an imine type compound of the following formula (D):
wherein X4 is CN or NO2, each of R7 and R8 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, and m is an integer of 1 to 5.
In the above imine compounds, the CN group or the NO2 group acts as the electron-accepting functional group and the NR5R6 group or the NR7R8 group acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
Here, when the above R5, R6, R7 or R8 is an alkyl groups, it is preferably an alkyl group having at most 6 carbon atoms, more preferably an alkyl group having at most 2 carbon atoms.
As such imine type compound, specifically, compounds of the following formulas (C-1) to (C-3) and (D-1) to (D-3) may, for example, be mentioned.
Further, it is also preferred to use a compound of the following formula (E):
wherein either one of Y1 and Y2 is a nitrogen atom, and another one thereof is a carbon atom having an amino group or a C1-6 alkylamino group as a substituent.
In the above compound, the nitro group acts as the electron-accepting functional group and the amino group or the alkylamino group acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
As such compound, specifically, compounds of the following formulas (E-1) and (E-2) may, for example, be mentioned.
Further, it is also preferred to use a compound of the following formula (F):
wherein each of R9 and R10 is a hydrogen atom or an alkyl group having at most 2 carbon atoms, and each of R11 and R12 is a hydrogen atom or an amino group.
In the above compound, the C═O group acts as the electron-accepting functional group and the N—R9 group and the N—R10 group act as the electron-donating functional groups, thereby providing the characteristic of bistablity.
As such compound, specifically, compounds of the following formulas (F-1), (F-2) and (F-3) may, for example, be mentioned.
Further, it is also preferred to use a compound of the following formula (G):
wherein each of R13, R14 and R15 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In this compound, the C═O group acts as the electron-accepting functional group and the N—R15 group acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
Here, when R13, R14 or R15 is an alkyl groups, it is an alkyl group having at most 6 carbon atoms, more preferably an alkyl group having at most 4 carbon atoms.
As such compound, specifically, compounds of the following formulas (G-1) and (G-2) may, for example, be mentioned.
Further, it is also preferred to use an iminequinone type compound of the following formula (H):
wherein each of R16 and R17 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, and each of R18 and R19 is an aryl group which may have a substituent, a C1-6 alkyl group which may have a substituent, or a hydrogen atom, provided that at least one of R18 and R19 is an aryl group which may have a substituent.
In the iminequinone type compound, the C═O group acts as the electron-accepting functional group and the C6H5 group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
Here, R16 or R17 is preferably an alkyl group having at most 6 carbon atoms, and when R18 or R19 is an alkyl groups, it is preferably an alkyl group having at most 6 carbon atoms, more preferably an alkyl group having at most 2 carbon atoms. When it is an alkyl group having more than 7 carbon atoms, molecular alignment necessary for conductivity is likely to be restricted and sufficient bistability is hardly obtainable, such being undesirable.
As such iminequinone type compound, specifically, compounds of the following formulas (H-1) to (H-4) may, for example, be mentioned.
Further, it is also preferred to use an iminequinone type compound of the following formula (H′):
wherein each of R70 and R71is a hydrogen atom, a C1-6 alkyl group which may have a substituent, or an aryl group which may have a substituent; R72 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, or an aryl group which may have a substituent; R73 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, an amino group which may have a substituent, or a residual group which may form a ring; or R72 and R73 may form a ring.
As such iminequinone type compound, specifically, compounds of the following formulas (H′-1) to (H′-9) may, for example, be mentioned.
Further, it is also preferred to use a quinoneimine compound of the following formula (I):
wherein each of R20 to R23 is a hydrogen atom or a C1-6 alkyl group which may have a substituent.
In the quinoneimine type compound, the C═O group acts as the electron-accepting functional group and the NH2 group, N(CH3)2 group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
Here, R20 or R21 is preferably an alkyl group having at most 6 carbon atoms. Further, when R22 or R23 is an alkyl group, it is preferably an alkyl group having at most 6 carbon atoms, more preferably an alkyl group having at most 2 carbon atoms. When it is an alkyl group having more than 7 carbon atoms, molecular alignment necessary for conductivity is likely to be restricted and sufficient bistability is hardly obtainable, such being undesirable.
As such quinoneimine type compound, specifically, compounds of the following formulas (I-1) to (I-3) may, for example, be mentioned.
Further, it is also preferred to use a dicyano type compound of the following formula (J):
wherein each of R24, R25 and R26 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, an aryl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, each of m and n is an integer of 1 to 5, and i is an integer of 1 to 4.
In the dicyano type compound, the CN group acts as the electron-accepting functional group and the N(C6H6)3 group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
Here, when R24, R25 or R26 is an alkyl group, it is preferably an alkyl group having at most 2 carbon atoms. When it is an alkyl group having more than 9 carbon atoms, molecular alignment necessary for conductivity is likely to be restricted and sufficient bistability is hardly obtainable, such being undesirable.
As such dicyano type compound, specifically, compounds of the following formulas (J-1) to (J-9) may, for example, be mentioned.
Further, it is also preferred to use a pyridone type compound of the following formula (K):
wherein each of R27, R28 and R29 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, or an aryl group which may have a substituent, R30 is a C1-6 alkyl group which may have a substituent, or a residual group which is capable of forming a ring, and i is an integer of 1 to 4.
Further, it is also preferred to use a pyridone type compound of the following formula (L):
wherein each of R31 and R32 is a hydrogen atom or a C1-6 alkyl group which may have a substituent, R33 is a C1-6 alkyl group which may have a substituent, or a residual group which is capable of forming a ring, each of R34 and R35 is an aryl group which may have a substituent, or a hydrogen atom, provided that at least one of R34 and R35 is an aryl group which may have a substituent, and i is an integer of 1 to 4.
In the pyridone type compound, the C═O group acts as the electron-accepting functional group and the C—N—(C5H4) group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
As such pyridone type compounds, specifically, compounds of the following formulas (K-1) to (K-9) and (L-1) to (L-8) may, for example, be mentioned.
Further, it is also preferred to use a quinoneimine type compound of the following formula (M):
wherein each of R36 and R37 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, or an aryl group which may have a substituent, R38 is a C1-6 alkyl group which may have a substituent, an aryl group which may have a substituent, or a residual group which is capable of forming a ring, and m is an integer of 1 to 5.
Further, it is also preferred to use a quinoneimine type compound of the following formula (N):
wherein each of R39 and R40 is a hydrogen atom or a C1-6 alkyl group which may have a substituent; each of R41, R42 and R43 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, an aryl group, or a residual group which is capable of forming a ring; i is an integer of 1 to 4; and each of m and n is an integer of 1 to 5.
In the quinoneimine type compounds, the C═O group acts as the electron-accepting functional group and the ═N—, triphenylamine group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
As such quinoneimine type compounds, specifically, compounds of the following formulas (M-1) to (M-9) and (N-1) to (N-9) may, for example, be mentioned.
Further, it is preferred to use a stilbene type compound of the following formula (O):
wherein each of R44, R45 and R46 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an amino group which may have a substituent, or an aryl group which may have a substituent; R47 is a hydrogen atom, a halogen atom, a nitro group, a cyano group or an aryl group which may have a substituent; each of m, n and o is an integer of 1 to 5; and i is an integer of 1 to 4.
In the stilbene type compound, the triphenylamine group or the like acts as the electron-donating functional group and the —Cl, —Br, —CN or —NO2 acts as the electron-accepting functional group, thereby providing the characteristic of bistablity.
As such stilbene type compound, specifically, compounds of the following formulas (O-1) to (O-11) may, for example, be mentioned.
Further, it is also preferred to use a butadiene type compound of the following formula (P):
wherein each of R48 and R49 is a hydrogen atom, a halogen atom, a nitro group, a cyano group or an aryl group which may have a substituent; each of R50 and R51 is a hydrogen atom, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an amino group which may have a substituent, or an aryl group which may have a substituent; and each of m, n, o and p is an integer of 1 to 5.
In the butadiene type compound, —CN, —NO2, —Br or —Cl acts as the electron-accepting functional group and the —CH3, —OCH3, —N(CH3)2 group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
As such butadiene type compounds, specifically, compounds of the following formulas (P-1) to (P-10) may, for example, be mentioned.
Further, it is also preferred to use a stilbene type compound of the following formula (Q):
wherein each of R52, R53, R54 and R55 is a hydrogen atom, a halogen atom, a nitro group, a cyano group, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an aryl group which may have a substituent, or a residual group forming a ring which may have a substituent; each of m and n is an integer of 1 to 5; i is an integer of 1 to 4; and q is an integer of 1 to 9.
In the stilbene type compound, the triphenylamine group or the like acts as the electron-donating functional group and —Cl, —Br, —CN or —NO2 group acts as the electron-accepting functional group, thereby providing the characteristic of bistablity.
As such stilbene type compounds, specifically, compounds of the following formulas (Q-1) to (Q-14) may, for example, be mentioned.
Further, it is also preferred to use a triphenylamine type compound of the following formula (R):
wherein each of R56, R57, R58, R59 and R60 is a hydrogen atom, a halogen atom, a nitro group, a cyano group, a C1-6 alkyl group which may have a substituent, a C1-6 alkoxyl group which may have a substituent, an aryl group which may have a substituent, or a residual group which is capable of forming a ring; each of m, n, o and p is an integer of 1 to 5; i is an integer of 1 to 4; and r is an integer of 1 to 2.
In the triphenylamine type compound, —CN, —NO2, —Br or —Cl acts as the electron-accepting functional group, and the —CH3, —OCH3, —N(CH3)2 group or the like acts as the electron-donating functional group, thereby providing the characteristic of bistablity.
As such triphenylamine type compound, specifically, compounds of the following formulas (R-1) to (R-27) may, for example, be mentioned.
The above organic bistable material is preferably incorporated in a form of thin film, a bistable material layer 30, such that an electrode layer 21a, the bistable material layer 30 and an electrode layer 21b are formed in order on a substrate 10. As the method for forming thin films, for the electrode layers 21a and 21b, conventional known methods such as a vapor deposition method are preferably used, and the forming method is not limited thereto.
Further, as the method for forming the bistable material layer 30, methods for preparing an organic film such as a spin coating method, an electrolytic polymerization method, a chemical vapor deposition (CVD) method and a Langmuir-Blodgett method, which is well known as a method to form mono-layer molecular films (LB method), may be mentioned. Although the formation method is not limited thereto, it is preferred to use the vapor deposition method where the same forming method as for the above electrode layers can be used.
The temperature of the substrate at the time of deposition can appropriately be selected depending upon the electrode material and the bistable material to be used. However, for the formation of the electrode layers 21a and 21b, 0 to 150° C. is preferred, and for the formation of the bistable material layer 30, 0 to 100° C. is preferred.
Further, the film of each layer is preferably 50 to 200 nm in thickness for the electrode layers 21a and 21b, and 20 to 150 nm in thickness for the bistable material layer 30.
The mechanism by which the switching element of the present invention obtainable by the above preparation method exhibits the characteristic of bistablity is unknown. However, from the mechanism in conventional two-component system material, the following is presumed. Namely, a mechanism is presumed wherein an electron-donating functional group of one molecule and an electron-accepting functional group of another molecule, both of the molecules being adjacent to each other, play together an equivalent roll of two-component system seen in conventional materials, so as to form a columnar structure and convert the material to a conductor.
It is explainable, by such mechanism where a single molecular is capable of functioning both as a donor and as an acceptor, intrinsically without any discrepancy in the compositional ratio of functional groups, that the characteristic of bistablity can be stably attained.
Further,
In this switching element, specifically saying, for example, it can be provided that the third electrode 23 is made of a silicon substrate, the insulating layers 41 and 42 are made of metallic oxide in a form of vapor deposition film, and the electrode layers 24a and 24b and the fourth electrode 25 are made of aluminum in a form of vapor deposition film.
Then, while the bias Vb explained in
Hereinbelow, the switching element of the present invention will be explained in more detail with reference to examples.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, an aminoimidazole type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 1. As the aminoimidazole type compound, a compound of the following formula (A-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the aminoimidazole type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 2 was obtained under the same conditions as in Example 1, provided that films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 3 was obtained under the same conditions as in Example 1, provided that a compound of the following formula (A-2) was used as the aminoimidazole type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 4 was obtained under the same conditions as in Example 1, provided that a compound of the following formula (A-3) was used as the aminoimidazole type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 100 nm and 100 nm, respectively.
A switching element of Example 5 was obtained under the same conditions as in Example 1, provided that a compound of the following formula (A-4) was used as the aminoimidazole type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 1 to 5 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 1 to 5, and the bistability state was attained such that the low threshold voltage Vth1 was 0.3 to 0.8 V and the high threshold voltage Vth2 was 2.3 to 5.7 V as shown in Table 1.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a γ-pyridone type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 6. As the γ-pyridone type compound, a compound of the following formula (B-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the γ-pyridone type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 7 was obtained under the same conditions as in Example 6, provided that a compound of the following formula (B-2) was used as the γ-pyridone type compound.
The current-voltage characteristics of the switching elements of Examples 6 and 7, measured under a room temperature environment, are shown in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, an imine type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 8. As the imine type compound, a compound of the following formula (C-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the imine type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 9 was obtained under the same conditions as in Example 8, provided that a compound of the following formula (C-2) was used as the imine type compound.
A switching element of Example 10 was obtained under the same conditions as in Example 8, provided that a compound of the following formula (C-3) was used as the imine type compound.
A switching element of Example 11 was obtained under the same conditions as in Example 8, provided that a compound of the following formula (D-1) was used as the imine type compound.
A switching element of Example 12 was obtained under the same conditions as in Example 8, provided that a compound of the following formula (D-2) was used as the imine type compound.
A switching element of Example 13 was obtained under the same conditions as in Example 8, provided that a compound of the following formula (D-3) was used as the imine type compound.
The current-voltage characteristics of the switching elements of Examples 8 to 13, measured under a room temperature environment, are shown in FIGS. 8 to 13, respectively. Further, the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in FIGS. 8 to 13 and Table 3, the switching elements of Examples 8 to 13 exhibit bistability obtained in which it was at high resistance state as represented by 108a, 109a, 110a, 111a, 112a, 113a and at low resistance state as represented by 108b, 109b, 110b, 111b, 112b, 113b, respectively.
Namely, as shown in
Further, as shown in
Further, as shown in
Further, as shown in
Further, as shown in
Further, as shown in
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a compound of the following formula (E-1) as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 14.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the compound of the formula (E-1) was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 15 was obtained under the same conditions as in Example 14, provided that a compound of the following formula (E-2) was used for the bistable material layer 30.
The current-voltage characteristics of the switching elements of Examples 14 and 15, measured under a room temperature environment, are shown in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a compound of the following formula (F-1) (manufactured by Sigma Aldrich Japan Co., Ltd.; Product No. 34679-9) as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 16.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the compound of the formula (F-1) was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 17 was obtained under the same conditions as in Example 16, provided that a compound of the following formula (F-2) (manufactured by Sigma Aldrich Japan Co., Ltd.; Product No. A5215-3) was used for the bistable material layer 30.
A switching element of Example 18 was obtained under the same conditions as in Example 16, provided that a compound of the following formula (F-3) (manufactured by Sigma Aldrich Japan Co., Ltd.; Product No. 85528-6) was used for the bistable material layer 30.
The current-voltage characteristics of the switching elements of Examples 16 to 18, measured under a room temperature environment, are shown in FIGS. 16 to 18, respectively. Further, the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in FIGS. 16 to 18 and Table 5, the switching elements of Examples 16 to 18 exhibit bistability obtained in which it was at high resistance state as represented by 116a, 117a, 118a and at low resistance state as represented by 116b, 117b, 118b, respectively.
Namely, as shown in
Further, as shown in
Further, as shown in
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a compound of the following formula (G-1) (manufactured by Sigma Aldrich Japan Co., Ltd.; Product No. 24,772-3) as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 19.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of compound of the formula (G-1) was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 20 was obtained under the same conditions as in Example 19, provided that a compound of the following formula (G-2) was used for the bistable material layer, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
The compound of the formula (G-2) was synthesized by the following procedure.
Namely, 9.7 g of 1,4-dimethylpyridinium iodide, 9.3 g of 3,5-di-t-butyl-4-hydroxybenzaldehyde and 3.7 g of piperidine were dissolved in 100 ml of ethanol, and then reflux was carried out at the boiling point of the solvent for 20 hours. After cooling to room temperature, precipitates were collected by filtration and suspended in 250 ml of a 0.2M KOH aqueous solution, followed by stirring under heating at 70° C. The precipitates were collected by filtration and washed with pure water and ethanol. Recrystallization was carried out with butanol to obtain 8.4 g (65%) of greenish plate-like crystals.
The current-voltage characteristics of the switching elements of Examples 19 and 20, measured under a room temperature environment, are shown in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, an iminequinone type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 21. As the iminequinone type compound, a compound of the following formula (H-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the iminequinone type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 22 was obtained under the same conditions as in Example 21, provided that films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 23 was obtained under the same conditions as in Example 21, provided that a compound of the following formula (H-2) was used as the iminequinone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 24 was obtained under the same conditions as in Example 21, provided that a compound of the following formula (H-3) was used as the iminequinone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 100 nm and 100 nm, respectively.
A switching element of Example 25 was obtained under the same conditions as in Example 21, provided that a compound of the following formula (H-4) was used as the iminequinone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 21 to 25 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 21 to 25, and the bistability state was attained such that the low threshold voltage Vth1 was −0.3 to −1.1 V and the high threshold voltage Vth2 was 1.3 to 2.5 V as shown in Table 7.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, an iminequinone type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 26. As the iminequinone type compound, a compound of the following formula (H′-3) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the iminequinone type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 27 was obtained under the same conditions as in Example 26, provided that a compound of the following formula (H′-4) was used as the iminequinone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 28 was obtained under the same conditions as in Example 26, provided that a compound of the following formula (H′-6) was used as the iminequinone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 26 to 28 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 26 to 28, and the bistability state was attained such that the low threshold voltage Vth1 was 0.1 to −0.6 V and the high threshold voltage Vth2 was 1.5 to 2.0 V as shown in Table 8.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a quinoneimine type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 29. As the quinoneimine type compound, a compound of the following formula (I-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the quinoneimine type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 30 was obtained under the same conditions as in Example 29, provided that films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 31 was obtained under the same conditions as in Example 29, provided that a compound of the following formula (I-2) was used as the quinoneimine type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 32 was obtained under the same conditions as in Example 29, provided that a compound of the following formula (I-3) was used as the quinoneimine type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 100 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 29 to 32 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 29 to 32, and the bistability state was attained such that the low threshold voltage Vth1 was 0.5 to 1.0 V and the high threshold voltage Vth2 was 2.1 to 3.5 V as shown in Table 9.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a dicyano type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 33. As the dicyano type compound, a compound of the following formula (J-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the dicyano type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 34 was obtained under the same conditions as in Example 33, provided that films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 35 was obtained under the same conditions as in Example 33, provided that a compound of the following formula (J-2) was used as the dicyano type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 36 was obtained under the same conditions as in Example 33, provided that a compound of the following formula (J-6) was used as the dicyano type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 37 was obtained under the same conditions as in Example 33, provided that a compound of the following formula (J-9) was used as the dicyano type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 33 to 37 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 33 to 37, and the bistability state was attained such that the low threshold voltage Vth1 was −0.6 to −1.4 V and the high threshold voltage Vth2 was 1.1 to 2.1 V as shown in Table 10.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a pyridone type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 38. As the pyridone type compound, a compound of the following formula (K-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the pyridone type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 39 was obtained under the same conditions as in Example 38, provided that films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 60 nm and 100 nm, respectively.
A switching element of Example 40 was obtained under the same conditions as in Example 38, provided that a compound of the following formula (K-2) was used as the pyridone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 41 was obtained under the same conditions as in Example 38, provided that a compound of the following formula (K-9) was used as the pyridone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 42 was obtained under the same conditions as in Example 38, provided that a compound of the following formula (L-7) was used as the pyridone type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 38 to 42 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 38 to 42, and the bistability state was attained such that the low threshold voltage Vth1 was 0.1 to −1.2 V and the high threshold voltage Vth2 was 1.8 to 2.7 V as shown in Table 11.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a quinoneimine type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 43. As the quinoneimine type compound, a compound of the following formula (M-4) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the quinoneimine type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 44 was obtained under the same conditions as in Example 43, provided that a compound of the following formula (M-8) was used as the quinoneimine type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 45 was obtained under the same conditions as in Example 43, provided that a compound of the following formula (M-9) was used as the quinoneimine type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 46 was obtained under the same conditions as in Example 43, provided that a compound of the following formula (N-4) was used as the quinoneamine type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 43 to 46 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 43 to 46, and the bistability state was attained such that the low threshold voltage Vth1 was 0.0 to −0.7 V and the high threshold voltage Vth2 was 1.4 to 2.8 V as shown in Table 12.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a stilbene type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 47. As the stilbene type compound, a compound of the following formula (O-3) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the stilbene type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element was prepared under the same conditions as in Example 47, provided that the bistable material of the formula (O-3) used in Example 47 was replaced to a bistable material of the following formula (O-6).
A switching element was prepared under the same conditions as in Example 47, provided that the bistable material of the formula (O-3) used in Example 47 was replaced to a bistable material of the following formula (O-7).
A switching element was prepared under the same conditions as in Example 47, provided that the bistable material of the formula (O-3) used in Example 47 was replaced to a bistable material of the following formula (O-9).
The current-voltage characteristics of the switching elements of Examples 47 to 50 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 47 to 50, and the bistability state was attained such that the low threshold voltage Vth1 was 0.8 to −0.5 V and the high threshold voltage Vth2 was 5.8 to 9.8 V as shown in Table 13.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a butadiene type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 51. As the butadiene type compound, a compound of the following formula (P-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the butadiene type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element of Example 52 was obtained under the same conditions as in Example 51, provided that a compound of the following formula (P-2) was used as the butadiene type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
A switching element of Example 53 was obtained under the same conditions as in Example 51, provided that a compound of the following formula (P-3) was used as the butadiene type compound, and films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively.
The current-voltage characteristics of the switching elements of Examples 51 to 53 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 51 to 53, and the bistability state was attained such that the low threshold voltage Vth1 was −0.6 to −1.4 V and the high threshold voltage Vth2 was 1.1 to 2.1 V as shown in Table 14.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a stilbene type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 54. As the stilbene type compound, a compound of the following formula (Q-4) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the stilbene type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
A switching element was prepared under the same conditions as in Example 54, provided that the bistable material of the formula (Q-4) used in Example 54 was replaced to a bistable material of the following formula (Q-5).
A switching element was prepared under the same conditions as in Example 54, provided that the bistable material of the formula (Q-4) used in Example 54 was replaced to a bistable material of the following formula (Q-7).
A switching element was prepared under the same conditions as in Example 54, provided that the bistable material of the formula (Q-4) used in Example 54 was changed to a bistable material of the following formula (Q-10).
The current-voltage characteristics of the switching elements of Examples 54 to 57 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
Here, as the measurement conditions, electrical resistance ranging from 100 kΩ to 1 MΩ was connected to each switching element in series, and a limited amount of current was applied in an ON-state so as to suppress the damage of the element by an over-current.
As shown in
Namely, as shown in
Further, as shown in
Further, the bistability was observed in all the switching elements of Examples 54 to 57, and the bistability state was attained such that the low threshold voltage Vth1 was 0 to 2 V and the high threshold voltage Vth2 was 3.2 to 15.5 V as shown in Table 15.
A switching element having the structure as shown in
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a triphenylamine type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 58. As the triphenylamine type compound, a compound of the following formula (R-1) was used.
Films of the electrode layer 21a, bistable material layer 30 and electrode layer 21b were formed in a thickness of 100 nm, 80 nm and 100 nm, respectively. Further, the deposition apparatus was used at a degree of vacuum of 3×10−6 torr by evacuation with a diffusion pump. The deposition of aluminum was conducted by an electrical resistance heater system at a film forming rate of 3 Å/sec, and the deposition of the triphenylamine type compound was conducted by an electrical resistance heater system at a film forming rate of 2 Å/sec. The deposition of each layer was continuously conducted by the same deposition apparatus under such condition that the sample did not contact air during the deposition.
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with gold as an electrode layer 21a, a triphenylamine type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 59. As the triphenylamine type compound, a compound of the following formula (R-21) was used.
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a triphenylamine type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 60. As the triphenylamine type compound, a compound of the following formula (R-24) was used.
On a glass substrate as a substrate 10, by a vapor deposition method, thin films were successively formed in order with aluminum as an electrode layer 21a, a triphenylamine type compound as a bistable material layer 30 and aluminum as an electrode layer 21b, to prepare a switching element of Example 61. As the triphenylamine type compound, a compound of the following formula (R-27) was used.
The current-voltage characteristics of the switching elements of Examples 58 to 61 were measured under a room temperature environment, and the values of threshold voltages thereof explained in
As shown in
Namely, as shown in
Further, as shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 2002-196734 | Jul 2002 | JP | national |
| 2002-196728 | Jul 2002 | JP | national |
| 2002-267688 | Sep 2002 | JP | national |
| 2002-246689 | Sep 2002 | JP | national |
| 2002-271911 | Sep 2002 | JP | national |
| 2002-271912 | Sep 2002 | JP | national |
| 2002-271910 | Sep 2002 | JP | national |
| 2002-271909 | Sep 2002 | JP | national |
| 2002-322055 | Nov 2002 | JP | national |
| 2003-036684 | Feb 2003 | JP | national |
| 2003-036683 | Feb 2003 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP03/08599 | 7/7/2003 | WO | 8/25/2005 |
