WO1996036082A1 - Dispositifs electroniques a base de cristaux liquides discoides - Google Patents

Dispositifs electroniques a base de cristaux liquides discoides Download PDF

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Publication number
WO1996036082A1
WO1996036082A1 PCT/GB1996/000744 GB9600744W WO9636082A1 WO 1996036082 A1 WO1996036082 A1 WO 1996036082A1 GB 9600744 W GB9600744 W GB 9600744W WO 9636082 A1 WO9636082 A1 WO 9636082A1
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Prior art keywords
dlc
doped
semiconducting
electrodes
electrode
Prior art date
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PCT/GB1996/000744
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English (en)
Inventor
Neville Boden
Bijan Movaghar
Jonathan Clements
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The University Of Leeds
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Publication date
Application filed by The University Of Leeds filed Critical The University Of Leeds
Priority to JP8533849A priority Critical patent/JPH11505068A/ja
Priority to EP96909217A priority patent/EP0827635A1/fr
Priority to AU52793/96A priority patent/AU5279396A/en
Publication of WO1996036082A1 publication Critical patent/WO1996036082A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
    • G11C13/0002—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements
    • G11C13/0009—RRAM elements whose operation depends upon chemical change
    • G11C13/0014—RRAM elements whose operation depends upon chemical change comprising cells based on organic memory material
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
    • G11C13/0002—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements
    • G11C13/0009—RRAM elements whose operation depends upon chemical change
    • G11C13/0014—RRAM elements whose operation depends upon chemical change comprising cells based on organic memory material
    • G11C13/0016—RRAM elements whose operation depends upon chemical change comprising cells based on organic memory material comprising polymers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/60—Organic compounds having low molecular weight
    • H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
    • H10K85/622—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene containing four rings, e.g. pyrene
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/731—Liquid crystalline materials

Definitions

  • the invention relates to electronic devices, and aspects thereof, which exploit the unique properties offered by discotic liquid crystals (DLC).
  • DLC discotic liquid crystals
  • the electronic devices are those which benefit from functioning at the molecular level, that is to say the transfer and/or detection of charge at the molecular level.
  • Such devices typically include, but are not limited to, devices where enhanced sensitivity is of advantage.
  • Examples of electronic devices in accordance with the invention include, but are not limited to the following devices.
  • a field effect transistor (FET) device which has potential application as: a radiation detector, a chemical/molecular detector, in the imaging of radiation on a molecular scale, as a temperature sensor, and in electronic photography etc. Providing this device with an array of micro-fabricated electrodes will lead to applications as a charge transfer device, a molecular registering device, a device for storage of information, and for electronic imaging.
  • Organic materials suitable for electronic devices dates back to the 1950's.
  • Organic materials possess a variety of advantages over the conventional use of silicon based semiconductor technologies. Among these advantages there is included the ability to control accurately the thickness of semiconductor deposition down to a thickness of only several molecular layers.
  • the infinite variety of organic molecules available allow chemists to tailor properties of the organic material to the particular application they require, for example to exhibit phosphorescence, fluorescence, magnetic and electrical properties.
  • the LB technique provides for a unique approach to achieve supra-molecular architectures of layered assemblies of suitably designed organic molecules including macro-molecules.
  • LB technology was designed to build layered assemblies of simple long chain aliphatic carboxylic acids and their salts. Later it was developed into a sophisticated method to produce supramolecular architectures useful to test molecularly controlled processes of heat transfer, charge carrier motion, energy conservation and molecular recognition.
  • the method and unique opportunities it offers for construction of molecular assemblies has found wide spread acceptance among physical chemists interested in the basic mechanisms of inter- molecular interactions of organic molecules, it has found little practical application.
  • amphiphilic polymers An alternative to the polymerisation of preformed layers of monomers is, the spreading and transfer of amphiphilic polymers along the lines of the LB method.
  • homo- or co-polymers of amphiphilic monomers are spread to the air-water interface, compressed and transferred. In most cases the transfer is only possible if a solid analogue phase of the side chains is formed.
  • Wegner 1 developed further the technology of applying LB techniques to polymeric compounds in his work on the Phthalocyaninatopolysiloxanes, which he refers to as "hairy-rods". Wegner 1 has applied this hairy rod technology to prototype electronic devices, in particular pH measuring devices.
  • Shimizu 3 has studied the photocurrent rectification behaviour of mesogenic 5,10,15,20-tetrakis (4-n-pentadecylphenyl) ⁇ o hyrin and has demonstrated that sandwiching a mesogen layer between two Indium-Tin Oxide electrodes resulted in a marked photocurrent rectification in the D h phase.
  • Bengs 4 investigated the photoconductivity in an homologous series of hexa- alkoxytriphenylenes. Under irradiation, all samples showed photoconductivity in the mesophase whereas in the isotropic phase, the photocurrents dropped to zero. All of the observed effects, ie the phase dependence of the photocurrent, the increasing values of photo- current with decreasing length of side chains, and the higher photoconductivity during cooling process, he explained in terms of the transition temperatures, the inter-columnar distances, and the orientation behaviour.
  • Adams 5 has studied the photoconduction in the mesophase of hexahexylthiotriphenylene. In his work, Adams discovered that the charge carrier mobility in the helical columnar (H) phase was far greater than in the D h phase, and of similar magnitude to the charge carrier mobilities in an organic single crystal.
  • UK patent document number 2 223 493 describes a discotic liquid crystalline material which is doped with a radical salt. This document goes on to describe that the discotic liquid crystalline phase possesses anisotropic electronic properties when either undoped or doped with less than 0.5 moles per mole of discotic liquid crystal.
  • inorganic semiconducting materials such as silicon and germanium were amongst the original materials used in semiconducting electronic devices.
  • advantages of manufacturing devices from inorganic materials such as silicon include their robustness and reliability.
  • inorganic semiconductors can be "cycled" many times without failure.
  • MBE Molecular Beam Epitaxy
  • inorganic materials such as silicon and germanium can only be chemically functionalised with difficulty due to their inert nature.
  • This drawback inhibits development of materials possessing novel physical and chemical properties which may find utility in electronic devices which exhibit characteristics such as phosphorescence, fluorescence, magnetic properties etc.
  • a further drawback of inorganic materials used in electronic devices is the requirement to use conducting adhesive material to join the electrode or gate with the inorganic semiconductor itself. The presence of an "adhesive layer" limits the extent of 3-dimensional miniaturisation of electronic devices due to the problems of constructing such devices.
  • a complication with electronic devices based on LB thin film technology arises from the grainy texture of the layered assemblies. This grainy texture arises during the course of making LB films, in which the amphiphilic molecules are spread on the air-water interface of a Langmuir trough. During this process, the LB film can rapidly form islands of two dimensional crystals which are compressed into a two dimensional continuous solid by action of a floating barrier.
  • a further drawback with LB thin film technology is that it relies on evaporative methodologies to apply the organic film onto the electrode surface. Evaporative methodologies tend to generate defects.
  • FET field effect transistor
  • a device which comprises:
  • first and second electrodes which electrodes have therebetween a film of discotic liquid crystal material and further wherein said first electrode comprises a low work function material and said second electrode comprises a high work function material.
  • the device In use, the device is connected to an electrical circuit, ideally externally, and a considerably larger current flows in the circuit when a relatively positive voltage is applied to said high work function electrode than if a relatively positive voltage is applied to said low work function electrode.
  • the magnitude of this effect is very sensitive to temperature. Particularly, but not exclusively at high temperatures.
  • said discotic liquid crystal is a 2,3,6,7,10,11 hexa-alkoxytriphenylene material and preferably 2,3,6,7,10,11 hexa-hexyloxytriphenylene (HAT6) material.
  • said low work function material is aluminium, calcium, barium or indeed any other material classified, or known as, low work function material.
  • said high work function material is Indium - Tin Oxide, silicon or gold or indeed any other material classified, or known as, high work function materials.
  • FET field effect transistor device
  • DLC discotic liquid crystal
  • the semiconductor will be silicon with a hydrogen passivated surface.
  • a gate voltage can be applied across said opposing outer first and second electrodes and a source-drain current can be detected across said thin layer, perpendicular to said gate voltage.
  • this device may find application in a range of electronic devices, for example, as a radiation detection device.
  • the absorption of radiation in said DLC material will lead to variations in the periodic charge modulation in the surface of said thin layer, leading to large variations in the source-drain current.
  • a further application may be in the field of chemical or molecular detection.
  • the molecules in said DLC material will sensitise the complex conductivity of the DLC and produce a significant variation in the source-drain current. This is again because such molecules in said DLC material will perturb the periodic charge modulation in the surface of said thin layer, leading to large variations in the source-drain current.
  • said first and second electrodes are metal.
  • said thin layer is metal or doped semiconductor.
  • said first electrode comprises a plurality of microfabricated electrodes.
  • this device will find a number of applications. For example as an electronic imaging device or a multistage memory device.
  • This periodic and regular modulation can be interrupted by external fields such as light sources in the range [0.1 to leV] and radiation (as described above) or molecules adsorbed in the electrode (as described above) to produce a change in said current.
  • Said voltage can also be pulsed and/or in conjunction with a radiation beam used to inject charge into said molecular wires and in turn into said thin layer and keep this charge, so to speak, as a memory for a given length of time, then the charge can be removed and detected by a change in said source-drain current.
  • Microfabricating said electrodes and or said source-drain current will allow us to achieve local addressability on a micron and submicron scale. This means we can store and return charge into said molecular wires with practically no sideways diffusion in different segments of the wire.
  • the anisotropy of the discotic system is lO O 4 for electronic transport.
  • said DLC material is 2,3,6,7,10,11 hexa-alkoxytriphenylene and preferably HAT6 material.
  • a device which comprises: two opposing outer first and second electrodes, having therebetween a p- doped DLC material in contact with the said first electrode; and an n-doped semiconducting material in contact with said second electrode and said p- doped DLC material.
  • a voltage is applied across said first and second electrodes, and a source-drain current is detechable across said n-doped semiconducting material.
  • Application of said voltage across said first and second electrodes separates the dopant counter ions and holes within said DLC material, and produces an "image" of the charge in said n-doped semiconductor material.
  • Said gates of this device are not only of molecular dimensions but also have the unique property of charge separation within the molecular wires of the columnar structure of said DLC material.
  • this device may find a number of applications.
  • the device may find application as a radiation detector.
  • the absorption of radiation inducing changes in the source-drain current include a molecular or chemical sensing device, absorption of molecules into the DLC materials altering the charge profile at said DLC material/said semiconducting material interface and affecting the source-drain current.
  • the device can be used to emit light at the junction between said p-doped DLC materials and said n-doped semiconducting materials.
  • Each emitter is a molecular wire.
  • said first electrode comprises a plurality of micro- fabricated electrodes. Provision of a plurality of micro-fabricated electrodes enables local addressability on a micron and sub-micron scale.
  • this device will find application in a number of applications.
  • this device will find application in a number of applications.
  • a molecular scale information storage device in transistor applications, and electronic imaging devices.
  • two distinct source-drain currents can be applied to the device across said n-doped semiconducting material perpendicular to said voltage, for example, one source-drain current can be detected at the interface of said p-doped DLC material and said n-doped semiconducting material, and another source-drain current can be detected at the interface of said n-doped semiconducting material and said second electrode.
  • said DLC material is a 2,3,6,7,10,11 hexa-alkoxytriphenylene material and preferably HAT6 material.
  • a plurality of, ideally, alternating semiconducting materials may be provided between said electrodes and in addition, a plurality of source-drain currents may be provided, ideally, each source-drain current is provided at or adjacent to the interface of said alternating materials.
  • a device which comprises:
  • a voltage is applied across said opposing first and second electrodes and a source-drain current is applied across said high mobility semiconducting material along an axis perpendicular to said voltage.
  • This device exploits the novel feature that on application of said voltage, positive charges are injected into said high mobility semiconducting material, and these charges carry current in the source-drain field, far away from the counter-ions which remain in said DLC material.
  • This device is quite unlike devices based upon ordinary doped high mobility semiconducting materials, where in use, the counter-ions remain in said high mobility semiconducting layers and act as scatterers reducing the mobility of the flow of the source- drain current.
  • the device offers the following features: a) An ultra-fast response in said source-drain current to changes in said voltage. This is because the device reduces the number of scattering centres in the bulk of said high mobility semiconducting material. b) A very thin DLC semiconducting material less than 100 A which acts as a quantum system for the injection of holes. The holes would then occupy sub-bands of the quantised system. c) More charge can be induced because of the higher capacitance. d) Greater light sensitivity because of space charge.
  • the device will find application in a number of devices, for example as a non linear optical device.
  • a six terminal device which accommodates two source-drain currents across said high mobility semiconducting material.
  • the first source-drain current is detected at the interface between said p- doped DLC thin film material and said high mobility semiconducting material.
  • the second source-drain current is detected at the interface between said high mobility semiconducting material and said second outermost electrode.
  • a relatively insulating material between said p-doped DLC thin film material and said high mobility semiconducting material.
  • a relatively insulating material between said high mobility semiconducting material and said second outermost electrode.
  • said p-doped DLC thin film material is a 2,3,6,7,10,11 hexa-alkoxytriphenylene material and preferably HAT6 material.
  • a device which comprises: a thin film of DLC material possessing two metal electrodes at the surface of said material and a third electrode within the bulk of said DLC material.
  • a voltage applied between one of said surface electrodes and said bulk electrodes would create a current which reacts sensitively to either absorbed molecules on the surface or light penetrating the DLC layer.
  • this device would find application as a sensitive chemical detector and/or a sensitive radiation detector, or in the field of electronic photography.
  • said surface and said bulk electrodes are metal.
  • said surface electrodes are 5 ⁇ m long, l ⁇ m deep, and ⁇ l m apart.
  • the arrangement of said electrodes is repeated periodically.
  • a device which comprises: two opposing outermost first and second electrodes, which first electrode is substantially transparent to electromagnetic radiation, and containing therebetween an undoped DLC thin film material in contact with said first electrode and a p-doped semiconducting material in contact with said second electrode and said undoped DLC thin film material; which DLC thin film material can exhibit fluorescent characteristics.
  • incident light passes through said transparent first electrode and creates excitons in said DLC thin film material which results in fluorescence.
  • a voltage pulse is applied across said first and second electrodes with said transparent first electrode held at a relatively negative potential.
  • Said voltage pulse causes positively charged holes to flow from said p-doped semiconducting material into said undoped fluorescing DLC thin film material.
  • the application of said voltage pulse lowers the fluorescing intensity because excitons generated in this region by the external light source transfer their energy to the charged molecules in said undoped DLC thin film via the F ⁇ rster mechanism.
  • Said charged molecules possess charge as they carry with them said positively charged holes.
  • said p-doped semiconducting material is a p-doped DLC material.
  • the diffusion of counter-ions, for example, aluminium trichloride , from said p-doped DLC material into said fluorescent DLC material can be reversed by the application of a voltage.
  • said p-doped semiconducting material is an inorganic p-doped semiconductor which has been conventionally optimised to provide easy injection of holes into said fluorescent DLC material.
  • DLC based fluorescent active devices possess several advantages over conventional fluorescent active (F-active) devices, for example:
  • DLC based F-active devices contain one-dimensional self-healing properties with relatively large charge carrier mobilities ( ⁇ 10 "3 cm 2 /Vs).
  • DLC based F-active devices exhibit efficient diffusion and trapping ( ⁇ t ) of excitons along the columns (D ⁇ 10 3 cm 2 /s and ⁇ t ⁇ 10 "8 s) because of the low dielectric constant ⁇ -2-4 and the efficient F ⁇ rster transfer rate - lO 12 ⁇ 1 . Furthermore, DLC based F-active devices exhibit charge separation in said p-doped layer which provides an efficient hole injection mechanism.
  • the device according to the sixth aspect of the invention will find application as a fluorescent switch and/or Optical Modulator Device Structure in, for example, television screen displays and devices which detect the arrival of charge, eg scintillation counters.
  • material preferably comprises a layer or film of material.
  • Figure 1 shows the structure of a typical discotic liquid crystal and the structure of a 2,3,6,7,10,11 hexa-alkoxytriphenylene (HAT6)
  • Figure 2 shows the device according to the first aspect of the invention.
  • Figure 3 shows Current v Voltage graph for the said first aspect of the invention.
  • Figure 4 shows the effect of temperature on the current at various voltages for said first aspect of the invention.
  • Figure 5 shows the device according to the second aspect of the invention.
  • Figure 6 shows the device according to the third aspect of the invention.
  • Figure 7 shows the device according the fourth aspect of the invention.
  • Figure 8 shows the device according to the fifth aspect of the invention.
  • Figure 9 shows the device according to the sixth aspect of the invention.
  • Figure 10 shows the effect of temperature on the conductivity at various voltages for HAT6.
  • Figure 11 shows how charge on discotic columns can be stored on a molecular scale using an ultra thin insulating (oxide) layer attached to a metallic gate.
  • Figure 12 shows schematically a typical potential curve seen by electrons in the 2-dimensional channel under the periodic array of discotic columns.
  • the application of gate voltage can change the depth of the potential and then switch the electronic band-structure.
  • Figure 1 shows the disordered stacked arrangement of the disc-shaped molecules within a discotic liquid crystal.
  • the structure can be described as a two-dimensional lattice of disordered stacks.
  • This structure imparts novel properties which can be applied to devices: a) the electronic band structure of organic solids combined with liquid ⁇ like properties. b) the ability to prepare thin (as thin as a few molecular layers), large area arrays of ordered molecules on surfaces. c) highly anisotropic charge carrier mobilities. d) self-healing of defects in the liquid crystalline state.
  • Figure 2 shows the device according to the first aspect of the invention. It comprises a high work function electrode 2 and a low work function electrode 3, and sandwiched therebetween is a thin film 1 of DLC material. Figure 2 also shows an external circuit for applying a potential difference across the electrodes.
  • Figure 3 shows a current against voltage plot obtained using the device shown in Figure 2.
  • the graph in Figure 3 clearly shows rectification in that a current only flows when a positive voltage is applied to the high work function electrode. No current flows in the external circuit when a negative voltage is applied to the high work function electrode.
  • Figure 4 shows a plot of the variation in current with temperature at voltages of 20, 50 and 100 volts when a positive voltage is applied to the high work function electrode of the device shown in Figure 2.
  • the plot at 100 volts shows a dramatic increase in current at 340K as HAT6 enters the liquid crystalline (D h ) phase, and also the dramatic fall in current as the phase changes from liquid crystalline (D h ) to liquid (I). It is at these phase transitions that the device will demonstrate the highest sensitivity to temperature, however throughout the D h phase the device shows high sensitivity to temperature as shown by the steeply curved portion of the graph represented by triangles
  • FIG. 5 there is shown a device according to the second aspect of the invention, which shows a Field Effect Transistor device which comprises electrodes 5 and 6, a discotic liquid film material 4 and a layer 7 of metal or doped semi-conductor.
  • Figure 5 also shows a voltage across electrodes 5 and 6, and a source-drain current across layer 7.
  • Figure 5 also indicates how an image of charge is created in the layer 7.
  • FIG. 6 there is shown a device according to the third aspect of the invention, which shows a field effect transistor device which comprises electrodes 10 and 11, a p-doped discotic liquid layer 8 and an n-doped semiconducting layer 9.
  • Figure 6 also shows a gate voltage across electrodes 10 and 11, and also a source-drain current across layer 9.
  • electrode 10 is comprised of a plurality of microfabricated gates 12.
  • FIG. 7 there is shown a device according to the fourth aspect of the invention which shows a high mobility FET comprising electrode 15 and 16, a layer of p-doped DLC material 14, and a layer of high mobility semiconducting material 13.
  • Figure 7 also shows relatively insulating layers 17 and 18.
  • Figure 7 also shows a voltage across electrodes 15 and 16.
  • Figure 7 also shows the application of two source-drain currents across the high mobility semiconducting material 13.
  • Figure 8 shows a device according to the fifth aspect of the invention.
  • Figure 8 shows a DLC layer 19, with electrodes 20 and 21 implanted at the surface and electrode 22 implanted in the bulk.
  • Figure 9 shows a device according to the sixth aspect of the invention.
  • Figure 9 shows an fluorescent undoped DLC layer 23 and a p-doped layer 24 which could comprise either DLC material or inorganic semiconducting material.
  • Figure 9 also shows said first transparent electrode 25 and second electrode 26.
  • the region ⁇ represents the 'skin-depth' which is the distance that the electromagnetic radiation ( ⁇ r ) enters said fluorescent undoped DLC material.
  • Figure 10 shows the effect of temperature on the conductivity of HAT6 at various voltages. These results show that this material is a very good insulator at these temperatures.
  • discotic liquid crystals form high quality insulating films and can replace, in part, the traditional insulating barrier in the gate of a field effect transistor [FET].
  • FET field effect transistor
  • the self assembled array of molecular wires address the two-dimensional electron gas formed in the inversion layer.
  • the molecular columns contact the semiconductor surface through a surface passivation layer, or if need be passivation "layers". In the case of a Silicon transistor, the passivation of the surface states would be achieved by a bonded monolayer of Hydrogen.
  • the coupling between the electrons in the channel and the molecular columns gives rise to a net potential which is in the range of 0.05 to 0.2 eN depending on molecule and gate potential applied. This potential is considerably larger than the thermal energy at room temperature.
  • the energy to trap an electron underneath a column in the active channel is of the order 0.2 to 0.5 eN.
  • By changing the gate voltage applied to the discotic film it is possible to increase the depth of the potential well in the channel by up to 0.1 eV in HAT-n and possibly more using materials with lower band gaps. In this way are in a unique position to engineer a class of FET devices in which the electronic band- structure can be switched from on state to another with the potentiality of arriving to complete localisation of the "band".
  • the band structure determines, in particular, the speed of electronic motion (mobility), the saturation velocities (maximum speed), and the magnitude of the band gaps.
  • the sensing device uses the fact that adsorbed molecules significantly change the complex conductance characteristics of the discotic film and in this way modify the potential which allows the channel to form and the electrons in the inversion layer to flow from source to drain.
  • the molecules are therefore detected as changes in the source drain current.
  • Selectivity can be achieved by using specially designed molecular side-chains which respond specifically to particular gases and adsorbed molecules. The specific response results from the strength of the inducing conduction change along and or across the molecular columns.

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  • Crystallography & Structural Chemistry (AREA)
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Abstract

L'invention concerne des dispositifs électroniques comprenant des cristaux liquides en forme de disques, dopés ou non dopés, et plus particulièrement, des cristaux liquides en forme de disques positionnés entre une paire constituée par une première et par une deuxième électrodes opposées. Les différents modes de réalisation peuvent s'utiliser dans une variété de dispositifs électroniques, tels que des détecteurs de température, des transistors à effet de champ, des dispositifs de détection de lumière, des dispositifs optiques non linéaires, des dispositifs de détection de rayonnement et de produits chimiques et des dispositifs fluorescents.
PCT/GB1996/000744 1995-05-13 1996-03-28 Dispositifs electroniques a base de cristaux liquides discoides WO1996036082A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP8533849A JPH11505068A (ja) 1995-05-13 1996-03-28 ディスコティック液晶をベースとした電子機器
EP96909217A EP0827635A1 (fr) 1995-05-13 1996-03-28 Dispositifs electroniques a base de cristaux liquides discoides
AU52793/96A AU5279396A (en) 1995-05-13 1996-03-28 Electronic devices based on discotic liquid crystals

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GBGB9509729.1A GB9509729D0 (en) 1995-05-13 1995-05-13 Electronic devices based on discotic liquid crystals
GB9509729.1 1995-05-13

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WO1996036082A1 true WO1996036082A1 (fr) 1996-11-14

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Cited By (7)

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Publication number Priority date Publication date Assignee Title
EP1028475A1 (fr) * 1999-02-09 2000-08-16 Sony International (Europe) GmbH Dispositif électronique comprenant une phase à structure colonnaire discotique
JP2002512451A (ja) * 1998-04-16 2002-04-23 ケンブリッジ ディスプレイ テクノロジー リミテッド ポリマー製素子
EP1365002A1 (fr) * 2002-05-22 2003-11-26 Universite Libre De Bruxelles Dérivés liquides cristallines pour dispositifs électroniques
EP1564280A1 (fr) * 2004-02-10 2005-08-17 Université Libre De Bruxelles Dérivés liquides cristallins pour dispositifs électroniques multicouches
EP1722424A1 (fr) * 2005-05-13 2006-11-15 Université Libre de Bruxelles Procédé d'alignement d'une couche de cristaux liquides discotiques
WO2009053981A2 (fr) * 2007-10-23 2009-04-30 Technion Research And Development Foundation Ltd. Dispositif de nez électronique présentant une faible sensibilité à l'humidité
US12022669B2 (en) 2021-12-01 2024-06-25 Kioxia Corporation Organic molecular memory

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JPH01189965A (ja) * 1988-01-26 1989-07-31 Matsushita Electric Ind Co Ltd 電界効果トランジスタ
GB2223493A (en) * 1988-10-10 1990-04-11 Nat Res Dev Conducting liquid crystals
WO1994029263A1 (fr) * 1993-06-16 1994-12-22 The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland Composes en forme de disque utilises dans des melanges pour cristaux liquides

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Cited By (10)

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Publication number Priority date Publication date Assignee Title
JP2002512451A (ja) * 1998-04-16 2002-04-23 ケンブリッジ ディスプレイ テクノロジー リミテッド ポリマー製素子
EP1028475A1 (fr) * 1999-02-09 2000-08-16 Sony International (Europe) GmbH Dispositif électronique comprenant une phase à structure colonnaire discotique
US6281430B1 (en) 1999-02-09 2001-08-28 Sony International (Europe) Gmbh Electronic device comprising a columnar discotic phase
EP1365002A1 (fr) * 2002-05-22 2003-11-26 Universite Libre De Bruxelles Dérivés liquides cristallines pour dispositifs électroniques
WO2003097770A1 (fr) * 2002-05-22 2003-11-27 Universite Libre De Bruxelles Derives cristallins liquides pour dispositifs electroniques
EP1564280A1 (fr) * 2004-02-10 2005-08-17 Université Libre De Bruxelles Dérivés liquides cristallins pour dispositifs électroniques multicouches
EP1722424A1 (fr) * 2005-05-13 2006-11-15 Université Libre de Bruxelles Procédé d'alignement d'une couche de cristaux liquides discotiques
WO2009053981A2 (fr) * 2007-10-23 2009-04-30 Technion Research And Development Foundation Ltd. Dispositif de nez électronique présentant une faible sensibilité à l'humidité
WO2009053981A3 (fr) * 2007-10-23 2009-06-04 Technion Res & Dev Foundation Dispositif de nez électronique présentant une faible sensibilité à l'humidité
US12022669B2 (en) 2021-12-01 2024-06-25 Kioxia Corporation Organic molecular memory

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GB9509729D0 (en) 1995-07-05
AU5279396A (en) 1996-11-29
JPH11505068A (ja) 1999-05-11

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