Abstract: A non-volatile memory (50) is disclosed. A second electrode (56) is provided. A first electrode (51) is also provided. A recording layer having a plurality of phase change cells (54) variable in resistance is provided between the first electrode (51) and the second electrode (56). A non-uniform tunnel barrier (540) is provided adjacent each of the recording layer and the first electrode. In use, the first electrode is in electrical communication with the non-uniform tunnel barrier, the first electrode for electrically communicating with the second electrode via the non-uniform tunnel barrier.

Abstract: A non-volatile memory is disclosed. A contiguous layer of phase change material is provided. Proximate the contiguous layer of phase change material is provided a first pair of contacts for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material for inducing heating thereof within a first region. Also adjacent the contiguous layer is provided a second pair of contacts disposed for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material for inducing heating thereof within a second region thereof, the second region different from the first region.

Abstract: An electronic device comprising a heat transfer structure and a phase change structure which is convertible between two phase states by heating, wherein the phase change structure is electrically conductive in at least one of the two phase states, wherein the heat transfer structure is arranged to be heated by radiation impinging on the heat transfer structure, wherein the phase change structure is thermally coupled to the heat transfer structure so that the phase change structure is convertible between the two phase states when the radiation impinges on the heat transfer structure.

Abstract: A non-volatile memory is disclosed. A contiguous layer of phase change material is provided. Proximate the contiguous layer of phase change material is provided a first pair of contacts for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material for inducing heating thereof within a first region. Also adjacent the contiguous layer is provided a second pair of contacts disposed for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material for inducing heating thereof within a second region thereof, the second region different from the first region.

Abstract: A non-volatile memory is disclosed. A contiguous layer of phase change material (21; 31; 61; 71; 81) is provided. Proximate the contiguous layer of phase change material (21; 31; 61; 71; 81) is provided a first pair of contacts (22; 32; 62; 72; 82) for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material (21; 31; 61; 71; 81) for inducing heating thereof within a first region. Also adjacent the contiguous layer is provided a second pair of contacts (22; 32; 62; 72; 82) disposed for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material (21; 31; 61; 71; 81) for inducing heating thereof within a second region thereof, the second region different from the first region. This pairs of contacts may be disposed on the same side or on opposing sides of the phase change material layer.

Abstract: An electronic device (100) comprising a heat transfer structure (103) and a phase change structure (104) which is convertible between two phase states by heating, wherein the phase change structure (104) is electrically conductive in at least one of the two phase states, wherein the heat transfer structure (103) is arranged to be heated by radiation (106) impinging on the heat transfer structure (103), wherein the phase change structure (104) is thermally coupled to the heat transfer structure (103) so that the phase change structure (104) is convertible between the two phase states when the radiation (106) impinges on the heat transfer structure (103).

Abstract: An electric device has an electrically switchable resistor (2?) comprising a phase change material. The resistance value of the resistor can be changed between at least two values by changing the phase of the phase change material within a part of the resistor called the switching zone (12?) using Joule heating of the resistor. The device comprises a body (24?) encapsulating the resistor, which body comprises at least two abutting regions (26?, 28?) having different thermally insulating properties. These regions form a thermally insulating contrast with which the dimension of the switching zone can be determined without having to alter the dimensions of the resistor. Such a device can be used in electronic memory or reconfigurable logic circuits.

Abstract: A non-volatile memory (50) is disclosed. A second electrode (56) is provided. A first electrode (51) is also provided. A recording layer having a plurality of phase change cells (54) variable in resistance is provided between the first electrode (51) and the second electrode (56). A non-uniform tunnel barrier (540) is provided adjacent each of the recording layer and the first electrode. In use, the first electrode is in electrical communication with the non-uniform tunnel barrier, the first electrode for electrically communicating with the second electrode via the non-uniform tunnel barrier.

Abstract: A non-volatile memory is disclosed. A contiguous layer of phase change material (21; 31; 61; 71; 81) is provided. Proximate the contiguous layer of phase change material (21; 31; 61; 71; 81) is provided a first pair of contacts (22; 32; 62; 72; 82) for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material (21; 31; 61; 71; 81) for inducing heating thereof within a first region. Also adjacent the contiguous layer is provided a second pair of contacts (22; 32; 62; 72; 82) disposed for providing an electrical current therebetween, the electrical current for passing through the contiguous layer of phase change material (21; 31; 61; 71; 81) for inducing heating thereof within a second region thereof, the second region different from the first region. This pairs of contacts may be disposed on the same side or on opposing sides of the phase change material layer.

Abstract: A thermally programmable memory has a programmable element (20) of a thermally programmable resistance preferably of phase change material, material and a blown antifuse (80) located adjacent to the programmable material. Such a blown antifuse has a dielectric layer (100) surrounded by conductive layers (90, 110) to enable a brief high voltage to be applied across the dielectric to blow a small hole in the dielectric during manufacture to form a small conductive path which can be used as a tiny electrical heater for programming the material. Due to the current confinement by the hole, the volume of the material that must be heated in order to switch to a highly-resistive state is very small. As a result the programming power can be low.

Abstract: An electric device has an electrically switchable resistor (2?) comprising a phase change material. The resistance value of the resistor can be changed between at least two values by changing the phase of the phase change material within a part of the resistor called the switching zone (12?) using Joule heating of the resistor. The device comprises a body (24?) encapsulating the resistor, which body comprises at least two abutting regions (26?, 28?) having different thermally insulating properties. These regions form a thermally insulating contrast with which the dimension of the switching zone can be determined without having to alter the dimensions of the resistor. Such a device can be used in electronic memory or reconfigurable logic circuits.

Abstract: A thermally programmable memory has a programmable element (20) of a thermally programmable resistance preferably of phase change material, material and a blown antifuse (80) located adjacent to the programmable material. Such a blown antifuse has a dielectric layer (100) surrounded by conductive layers (90, 110) to enable a brief high voltage to be applied across the dielectric to blow a small hole in the dielectric during manufacture to form a small conductive path which can be used as a tiny electrical heater for programming the material. Due to the current confinement by the hole, the volume of the material that must be heated in order to switch to a highly-resistive state is very small. As a result the programming power can be low.

Abstract: The present invention concerns in a first aspect a spin-valve structure having a first and a second free ferromagnetic layer and a spacer layer positioned between the first and second free ferromagnetic layer, and wherein the first free ferromagnetic layer is positioned on a substrate. In a preferred embodiment of the invention, the first free ferromagnetic layer is in direct contact with the surface of the substrate.

Abstract: The present invention concerns in a first aspect a spin-valve structure having a first and a second free ferromagnetic layer and a spacer layer positioned between the first and second free ferromagnetic layer, and wherein the first free ferromagnetic layer is positioned on a substrate. In a preferred embodiment of the invention, the first free ferromagnetic layer is in direct contact with the surface of the substrate.