A method is presented for enabling heat dissipation in resistive random access memory (RRAM) devices. The method includes forming a plurality of conductive lines within an interlayer dielectric (ILD) and forming a RRAM stack over a conductive line of the plurality of conductive lines, the RRAM stack including a bottom electrode, a conductive pillar, thermal conducting layers, and a top electrode. The thermal conducting layers are disposed on opposed ends of the conductive pillar. The thermal conducting layers directly contact the top electrode and the bottom electrode. The thermal conducting layers include aluminum oxide (Al.sub.2O.sub.3).

A method comprises activating an interval timer to expire in a calibration time interval and, in response to the timer expiring, performing an impedance analysis of an electronic network. The impedance analysis can use time-domain reflectometry. Based on the analysis, the method can calibrate a variable impedance device to have a first impedance and re-activate the timer. The method can perform a second impedance analysis based on calibrating the variable impedance device. The method can include determining a drift rate and modifying the calibration time interval. The variable impedance device can comprise a phase-change material (PCM), and the time interval can correspond to a retention time of the PCM and/or a dynamic drift rate. A system comprising a segment of an electronic network, a timer, a variable impedance device, and an impedance tuning system can embody operations of the method.

In manufacturing a radio frequency (RF) switch, a heat spreader is provided. A first dielectric is deposited over the heat spreader. A trench is etched in the first dielectric. A heating element is deposited in the trench and over at least a portion of the first dielectric. A thermally conductive and electrically insulating material is deposited over at least the heating element, where the thermally conductive and electrically insulating material is self-aligned with the heating element. A conformability support layer is optionally deposited over the thermally conductive and electrically insulating material and the first dielectric. A phase-change material is deposited over the optional conformability support layer and the underlying thermally conductive and electrically insulating material and the first dielectric.

In various embodiments, an improved structure for a PCM device is provided. The improved structure is configured to help prevent heat dissipation. In one example, the PCM device is an PCM RF Switch, which has a substrate, a heater, a dielectric/insulator layer, oxidation layers, electrodes, a PCM region, and/or any other components. The oxidation layers are configured to help prevent heat dissipation from the heater.

The present invention is notably directed to display device (1, 1a d), comprising a set of pixels, each having a layer structure (2, 2c, 2d) that includes: a bi-stable, phase change material (10), or bi-stable PCM, having at least two reversibly switchable states, in which the PCM exhibits two different values of refractive index and/or optical absorption; and a heating element (17, 17c, 17d), electrically insulated from the PCM (10) and in thermal communication with the PCM (10) in the layer structure (2, 2c, 2d). The display device further comprises a set of nonlinear, monostable resistive switching elements (21), each in electrical communication with the heating element (17, 17c, 17d) of one of the pixels. The resistive switching elements are designed so as to exhibit, each: a low resistance, unstable state, which allows the heating element (17, 17c, 17d) to be energized via the resistive switching element (21), so as to heat the PCM (10) and reversibly change a refractive index and/or an optical absorption thereof, in operation; and a high-resistance, stable state, which allows leakage currents to be mitigated, so as to prevent inadvertent switching of the PCM (10) from one of its states to the other, in operation. The device further comprises a controller (30) configured to energize any of the pixels via a respective one of the resistive switching elements (21), so as to switch the latter from its high-resistance state to its low resistance state, in order to energize a respective heating element (17, 17c, 17d) and, in turn, reversibly change a refractive index and/or an optical absorption of a respective PCM (10). The present invention is further directed to related devices or apparatuses, such as passive matrix addressing displays, and methods of operations.

A radio frequency (RF) switch includes a phase-change material (PCM), a heating element underlying an active segment of the PCM and extending outward and transverse to the PCM, and RF terminals having lower metal portions and upper metal portions. At least one of the lower metal portions can be ohmically separated from and capacitively coupled to passive segments of the PCM, while the upper metal portions are ohmically connected to the lower metal portions. Alternatively, the lower metal portions can be ohmically connected to passive segments of the PCM, while a capacitor is formed in part by at least one of the upper metal portions. Alternatively, at least one of the RF terminals can have a trench metal liner separated from a trench metal plug by a dielectric liner. The trench metal liner can be ohmically connected to passive segments of the PCM, while the trench metal plug is ohmically separated from, but capacitively coupled to, the trench metal liner.

A phase change memory (PCM) cell with enhanced thermal isolation and low power consumption is provided. In some embodiments, the PCM cell comprises a bottom electrode, a dielectric layer, a heating element, and a phase change element. The dielectric layer is on the bottom electrode. The heating element extends through the dielectric layer, from a top of the dielectric layer to the bottom electrode. Further, the heating element has a pair of opposite sidewalls laterally spaced from the dielectric layer by a cavity. The phase change element overlies and contacts the heating element. An interface between the phase change element and the heating element extends continuously respectively from and to the opposite sidewalls of the heating element. Also provided is a method for manufacturing the PCM cell.

A method is presented for reducing a reset current for a phase change memory (PCM). The method includes forming a bottom electrode, constructing a PCM cell structure including a plurality of phase change memory layers and a plurality of heat transfer layers, wherein the plurality of phase change memory layers are assembled in an alternating configuration with respect to the plurality of heat transfer layers, and forming a top electrode over the PCM cell structure. The plurality of phase change memory layers are arranged perpendicular to the top and bottom electrodes. Additionally, airgaps are defined adjacent the PCM cell structure.

The switching device includes three terminals including an inner surface, an oxide layer on the inner surface of the third terminal, and a chalcogenide pillar extending through the oxide layer and the third terminal, the pillar being in electrical communication with the first terminal and the second terminal, wherein the voltage difference between the first terminal and the second terminal changes the channel from a first state to a second state when a threshold voltage between the first terminal and the second terminal is exceeded, the threshold voltage being dependent on temperature. The third terminal is resistive and receives a control signal to apply heat to the pillar and modulate the threshold voltage. The switching device can be used to select the memory stack through the bitline and provide a nearly limitless current based on the threshold switching conduction providing avalanche current conduction through the switching device.

A radio frequency (RF) switch includes a heating element, thermally conductive and electrically insulating layer over the heating element, a wetting dielectric layer over the thermally conductive and electrically insulating layer, and a phase-change material (PCM) over the wetting dielectric layer. At least one cladding dielectric layer can be situated over sides and/or over a top surface of the PCM. Each of the wetting dielectric layer, phase change material, and cladding dielectric layer can comprise at least germanium. A transitional dielectric layer can be situated between the thermally conductive and electrically insulating layer and the wetting dielectric layer. A contact uniformity support layer can be situated over the cladding dielectric layer.