Abstract: An example wearable device is provided, that includes at least two dry electrodes that are electrically coupled with an external body surface of a wearer configured to obtain a neuromuscular signal. The example wearable device includes at least two dry electrodes that are electrically coupled with an external body surface of a wearer configured to obtain a neuromuscular signal. The example wearable device includes an amplifier configured to amplify the neuromuscular signals received from the at least two dry electrodes to produce an output signal. And the example wearable device includes one or more processors configured to obtain information identifying impedance associated with at least one of the two dry electrodes, wherein the information identifying the impedance is determined based on (i) the output signal from the amplifier and (ii) a characteristic of the amplifier.

Abstract: Examples are disclosed that relate to operating an electrodeposition system comprising an inert anode. In one example system, the electrodeposition system includes a substrate holder and a cathode chamber configured to hold a catholyte. An anode chamber configured to hold an anolyte during the electrodeposition process comprises an inert anode. An intermediate chamber is positioned between the cathode chamber and the anode chamber. The intermediate chamber is separated from the cathode chamber by an ion exchange membrane.

Abstract: According to some embodiments, a device for sensing neuromuscular signals is provided. The device may comprise a plurality of signal electrodes aligned along an interior portion of a wearable structure, each signal electrode being configured to detect neuromuscular signals. The device may comprise a plurality of amplifiers, wherein each amplifier includes (i) a first input operatively coupled to a corresponding signal electrode, (ii) an inverting input, and (iii) an output corresponding to a neuromuscular signal channel. The device may comprise one or more buffers configured to tap a voltage at the inverting input of a respective amplifier of the plurality of amplifiers. The device may comprise circuitry configured to operatively couple a plurality of outputs of the plurality of amplifiers to generate a common mode reference signal, wherein the common mode reference signal is provided to the inverting input of one or more amplifiers of the plurality of amplifiers.

Abstract: The disclosed computer-implemented method may include (1) sampling an output signal of an amplifier that amplifies a voltage difference between two electrodes, (2) calculating, based on a power spectral density of the output signal, a noise power of the output signal over a predetermined frequency band, (3) estimating an interface impedance of at least one of the two electrodes based on the noise power and a predetermined intrinsic current noise of the amplifier, and (4) performing an operation based at least in part on the estimated interface impedance. Various other methods, systems, and devices are also disclosed.

Abstract: Methods and systems for reducing electromagnetic interference in analog circuit of a control device for an augmented reality (AR) or virtual reality (VR) system are described. An analog circuit associated with the control device may include at least one amplifier and an analog-to-digital converter coupled to an amplifier by one or more electrical conductors. Electromagnetic interference induced in the one or more electrical conductors by an external AC magnetic field may be reduced using at least one component of the control device configured to reduce the electromagnetic interference.

Abstract: Disclosed herein are methods, systems, apparatuses, and media for sensing neuromuscular signals. In one example, a device for sensing neuromuscular signals comprises a wearable structure. The device includes a plurality of signal electrodes aligned along an interior portion of the wearable structure, each signal electrode configured to detect neuromuscular signals. The device further includes a plurality of amplifiers corresponding to the plurality of signal electrodes, wherein an amplifier has: a first input operatively coupled to a corresponding signal electrode; a second input; and an output corresponding to a neuromuscular signal channel. The device further includes circuitry configured to generate a common mode reference signal directly or indirectly based on signals from one or more electrodes, wherein the second input of each amplifier of the plurality of amplifiers is configured to receive the common mode reference signal or a signal based on the common mode reference signal.

Abstract: Techniques for shielding wearable surface electromyography (sEMG) devices are described. According to some aspects, an sEMG device may comprise amplification circuitry comprising at least a first differential amplifier and at least two sEMG electrodes electrically connected to the amplification circuitry. The device may further comprise at least one auxiliary conductor not electrically connected to the amplification circuitry, wherein the at least one auxiliary conductor is configured to be electrically coupled to a wearer of the wearable device, and an electromagnetic shield surrounding the wearable device at least in part and electrically connected to the at least one auxiliary conductor.

Abstract: Arrangements for improving neuromuscular recording electrode contact with a body surface are described. According to some aspects, a sensor assembly may include a housing and one or more electrodes that are moveable relative to the housing. The electrodes may rotate and/or translate relative to the housing and/or have at least two degrees of freedom relative to the housing. The sensor may include a spring element that stores potential energy and biases the electrodes toward a starting position in which the electrodes extend at least partially out of the sensor housing. In some embodiments, application of a contact force to one or more of the electrodes of the sensor compresses the spring element, causing the spring element to store potential energy.

Abstract: Techniques for shielding wearable surface electromyography (sEMG) devices are described. According to some aspects, an sEMG device may comprise amplification circuitry comprising at least a first differential amplifier and at least two sEMG electrodes electrically connected to the amplification circuitry. The device may further comprise at least one auxiliary conductor not electrically connected to the amplification circuitry, wherein the at least one auxiliary conductor is configured to be electrically coupled to a wearer of the wearable device, and an electromagnetic shield surrounding the wearable device at least in part and electrically connected to the at least one auxiliary conductor.

Abstract: Arrangements for improving neuromuscular recording electrode contact with a body surface are described. According to some aspects, a sensor assembly may include a housing and one or more electrodes that are moveable relative to the housing. The electrodes may rotate and/or translate relative to the housing and/or have at least two degrees of freedom relative to the housing. The sensor may include a spring element that stores potential energy and biases the electrodes toward a starting position in which the electrodes extend at least partially out of the sensor housing. In some embodiments, application of a contact force to one or more of the electrodes of the sensor compresses the spring element, causing the spring element to store potential energy.

Abstract: Techniques for shielding wearable surface electromyography (sEMG) devices are described. According to some aspects, an sEMG device may comprise amplification circuitry comprising at least a first differential amplifier and at least two sEMG electrodes electrically connected to the amplification circuitry. The device may further comprise at least one auxiliary conductor not electrically connected to the amplification circuitry, wherein the at least one auxiliary conductor is configured to be electrically coupled to a wearer of the wearable device, and an electromagnetic shield surrounding the wearable device at least in part and electrically connected to the at least one auxiliary conductor.

Abstract: In some method and apparatus disclosed herein, the profile of current delivered to the substrate provides a relatively uniform current density on the substrate surface during immersion. These methods include controlling the current density applied across a substrate's surface during immersion by dynamically controlling the current to account for the changing substrate surface area in contact with electrolyte during immersion. In some cases, current density pulses and/or steps are used during immersion, as well.

Abstract: An apparatus for electroplating a layer of metal onto the surface of a wafer includes an ionically resistive ionically permeable element located in close proximity of the wafer and an auxiliary cathode located between the anode and the ionically resistive ionically permeable element. The ionically resistive ionically permeable element serves to modulate ionic current at the wafer surface. The auxiliary cathode is configured to shape the current distribution from the anode. The provided configuration effectively redistributes ionic current in the plating system allowing plating of uniform metal layers and mitigating the terminal effect.

Abstract: In a copper electroplating apparatus having separate anolyte and catholyte portions, the concentration of anolyte components (e.g., acid or copper salt) is controlled by providing a diluent to the recirculating anolyte. The dosing of the diluent can be controlled by the user and can follow a pre-determined schedule. For example, the schedule may specify the diluent dosing parameters, so as to prevent precipitation of copper salt in the anolyte. Thus, precipitation-induced anode passivation can be minimized.

Abstract: Apparatus and methods for filling through silicon vias (TSV's) with copper having an intervening tungsten layer between the copper plug and the silicon are disclosed. Methods are useful for Damascene processing, with or without a TSV feature. The tungsten layer serves as a diffusion barrier, a seed layer for copper electrofill and a means of reducing CTE-induced stresses between copper and silicon. Adhesion of the tungsten layer to the silicon and of the copper layer to the tungsten is described.

Abstract: An apparatus for electroplating a layer of metal onto the surface of a wafer includes an ionically resistive ionically permeable element located in close proximity of the wafer and an auxiliary cathode located between the anode and the ionically resistive ionically permeable element. The ionically resistive ionically permeable element serves to modulate ionic current at the wafer surface. The auxiliary cathode is configured to shape the current distribution from the anode. The provided configuration effectively redistributes ionic current in the plating system allowing plating of uniform metal layers and mitigating the terminal effect.

Abstract: An apparatus for electroplating a layer of metal onto the surface of a wafer includes an ionically resistive ionically permeable element located in close proximity of the wafer and an auxiliary cathode located between the anode and the ionically resistive ionically permeable element. The ionically resistive ionically permeable element serves to modulate ionic current at the wafer surface. The auxiliary cathode is configured to shape the current distribution from the anode. The provided configuration effectively redistributes ionic current in the plating system allowing plating of uniform metal layers and mitigating the terminal effect.

Abstract: An apparatus for electroplating a layer of metal onto the surface of a wafer includes an ionically resistive ionically permeable element located in close proximity of the wafer and an auxiliary cathode located between the anode and the ionically resistive ionically permeable element. The ionically resistive ionically permeable element serves to modulate ionic current at the wafer surface. The auxiliary cathode is configured to shape the current distribution from the anode. The provided configuration effectively redistributes ionic current in the plating system allowing plating of uniform metal layers and mitigating the terminal effect.

Abstract: Apparatus and methods for depositing copper on tungsten are presented. The invention finds particular use in the semiconductor industry for depositing copper seed layers onto fields or through silicon vias having tungsten barrier layers, both reducing cost and complexity of existing methods.

Abstract: An apparatus for electroplating a layer of metal on the surface of a wafer includes an ionically resistive ionically permeable element located in close proximity of the wafer (preferably within 5 mm of the wafer surface) which serves to modulate ionic current at the wafer surface, and a second cathode configured to divert a portion of current from the wafer surface. The ionically resistive ionically permeable element in a preferred embodiment is a disk made of a resistive material having a plurality of perforations formed therein, such that perforations do not form communicating channels within the body of the disk. The provided configuration effectively redistributes ionic current in the plating system allowing plating of uniform metal layers and mitigating the terminal effect.