7405 results about "Current density" patented technology

A laser diode, grown on a miscut nonpolar or semipolar substrate, with lower threshold current density and longer stimulated emission wavelength, compared to conventional laser diode structures, wherein the laser diode's (1) n-type layers are grown in a nitrogen carrier gas, (2) quantum well layers and barrier layers are grown at a slower growth rate as compared to other device layers (enabling growth of the p-type layers at higher temperature), (3) high Al content electron blocking layer enables growth of layers above the active region at a higher temperature, and (4) asymmetric AlGaN SPSLS allowed growth of high Al containing p-AlGaN layers. Various other techniques were used to improve the conductivity of the p-type layers and minimize the contact resistance of the contact layer.

A magnetoresistive element which records information by supplying spin-polarized electrons to a magnetic material, includes a first pinned layer which is made of a magnetic material and has a first magnetization directed in a direction perpendicular to a film surface, a free layer which is made of a magnetic material and has a second magnetization directed in the direction perpendicular to the film surface, the direction of the second magnetization reversing by the spin-polarized electrons, and a first nonmagnetic layer which is provided between the first pinned layer and the free layer. A saturation magnetization Ms of the free layer satisfies a relationship 0≧Ms<√{square root over ( )}{Jw/(6nAt)}. Jw is a write current density, t is a thickness of the free layer, A is a constant.

A magnetic random access memory device comprises a spin torque MRAM cell (100) having a reduced switching current (I_c) wherein standard materials may be used for a free layer (108). A fixed magnetic element (112) polarizes electrons passing therethrough, and the free magnetic element (108) having a first plane anisotropy comprises a first magnetization (130) whose direction is varied by the spin torque of the polarized electrons. An insulator (110) is positioned between the fixed magnetic element (112) and the free magnetic element (108), and a keeper layer (104) positioned contiguous to the free magnetic element (108) and having a second plane anisotropy orthogonal to the first plane anisotropy, reduces the first plane anisotropy and hence reduces the spin torque switching current (I_c). The keeper layer (104) may comprise alternating synthetic antiferromagnetic layers (132, 134) of magnetization approximately equal in magnitude and opposite in direction.

A high efficient white emission light emitting element having peak intensity in each wavelength region of red, green, and blue is provided. Specifically, a white emission light emitting element having an emission spectrum that is independent of current density is provided. A first light emitting layer 312 exhibiting blue emission and a second light emitting layer 313 containing a phosphorescent material that generates simultaneously phosphorescent emission and excimer emission are combined. In order to derive excimer emission from the phosphorescent material, it is effective to disperse a phosphorescent material 323 having a high planarity structure such as platinum complex at a high concentration of at least 10 wt % to a host material 322. Further, the first light emitting layer 312 is provided to be in contact with the second light emitting layer 313 at the side of an anode. Ionization potential of the second light emitting layer 313 is preferably larger by 0.4 eV than that of the first light emitting layer 312.

A self-limiting electrosurgical return electrode for use with electrosurgery. Through the selection of impedance characteristics for the electrode materials of the principal body of the electrode, and through tailoring of electrode geometries, the return electrode of the present invention is self-regulating and self-limiting as to current density and temperature rise so as to prevent patient trauma. The electrosurgical return electrode includes a sheet of material having an effective bulk impedance equal to or greater than about 4,000 OMEGA.cm and one or more connectors for making electrical connection to the sheet. The effective bulk impedance of the sheet may arise from resistive components, capacitive components, inductive components, or combinations thereof. The configuration of the presently described return electrode allows the electrode to self-limit the electrode's current densities, thereby preventing burning of a patient during surgery. Furthermore, through employment of washable surface areas, the electrode is made readily cleanable, disinfectable, sterilizable, and reusable. An optional sleeve is provided for cooperative use with the electrode.

A transmitter consists of a plurality of magnetic transmitters, each of which is substantially planar and made of a spiral shaped conductor. The result is a transmitter having a substantially uniform cross-sectional current density along the radial direction of the spiral from the center to the periphery. Near the plane of a given spiral, magnetic vectors produced by such a conductor arrangement have improved angular characteristics as compared to prior art systems. This results in a larger region with useful vector crossing angles and operation of the system is enhanced as compared to prior art techniques. The transmitters produce magnetic fields which have a monotonically increasing intensity as one approaches the center of the transmitter spiral from any given direction. This feature simplifies and increases the accuracy of sensor position determination. If desired, the turns of the spiral transmitter may become closer together as one goes from the periphery to the center thereof to thereby concentrate the magnetic field more centrally of the transmitter. Transmitters having one or two spiral coils are also contemplated.

A layer of nanopaiticles having a dimension on the order of 10 nm is employed to form a current constricting layer or as a hardmask for forming a current constricting layer from an underlying insulator layer. The nanoparticles are preferably self-aligning and/or self-planarizing on the underlying surface. The current constricting layer may be formed within a bottom conductive plate, within a phase change material layer, within a top conductive plate, or within a tapered liner between a tapered via sidewall and a via plug contains either a phase change material or a top conductive material. The current density of the local structure around the current constricting layer is higher than the surrounding area, thus allowing local temperature to rise higher than surrounding material. The total current required to program the phase change memory device, and consequently the size of a programming transistor, is reduced due to the current constricting layer.

An electrochemical microfluidic device has one or a plurality of microstructures, such as a microchannel, in which an electrically conductive means is integrated to reduce the ohmic resistance within the microstructure and hence to improve electrochemical measurements particularly when large current densities are involved. The electrically conductive means can be connected as a counter-electrode and can be used to re-generate the product of the reaction occurring at the working electrode. A method of fabricating electrochemical microfluidic devices comprising such an electrically conductive means is also disclosed. The invention may particularly be used in all electrochemical sensor applications where detection is performed in small volumes.

One aspect of the invention provides a consistent metal electroplating technique to form void-less metal interconnects in sub-micron high aspect ratio features on semiconductor substrates. One embodiment of the invention provides a method for filling sub-micron features on a substrate, comprising reactive precleaning the substrate, depositing a barrier layer on the substrate using high density plasma physical vapor deposition; depositing a seed layer over the barrier layer using high density plasma physical vapor deposition; and electro-chemically depositing a metal using a highly resistive electrolyte and applying a first current density during a first deposition period followed by a second current density during a second period.

This invention encompasses methods of producing a colored oxide layer on an aluminum material by anodizing the aluminum material in an electrolyte comprising water, sulfuric acid and oxalic acid. The anodizing step comprises passing at least two sequential current densities through the electrolyte. Methods of making and using article with a colored oxide layer on an aluminum material make by the methods disclosed herein are also disclosed.

A method of producing nano-scaled graphene platelets with an average thickness smaller than 30 nm from a layered graphite material. The method comprises (a) forming a carboxylic acid-intercalated graphite compound by an electrochemical reaction which uses a carboxylic acid as both an electrolyte and an intercalate source, the layered graphite material as an anode material, and a metal or graphite as a cathode material, and wherein a current is imposed upon the cathode and the anode at a current density for a duration of time sufficient for effecting the electrochemical reaction; (b) exposing the intercalated graphite compound to a thermal shock to produce exfoliated graphite; and (c) subjecting the exfoliated graphite to a mechanical shearing treatment to produce the nano-scaled graphene platelets. Preferred carboxylic acids are formic acid and acetic acid. The exfoliation step in the instant invention does not involve the evolution of undesirable species, such as NO_x and SO_x, which are common by-products of exfoliating conventional sulfuric or nitric acid-intercalated graphite compounds. The nano-scaled platelets are candidate reinforcement fillers for polymer nanocomposites. Nano-scaled graphene platelets are much lower-cost alternatives to carbon nano-tubes or carbon nano-fibers.

An electrosurgical instrument, system and methods are provided for the vaporization, cutting, coagulation, or treatment of tissue in the presence of an electrically conductive fluid medium. The electrosurgical probe comprises at least one active electrode, and at least one “floating” electrode having at least one end in close proximity to at least one active electrode. The floating electrode is not connected in any way to the electrosurgical power supply, but rather has a “floating” potential determined by the shape and position of the electrode. The floating electrode increases current density in the region of the probe distal end.

A method of determining the voltage and current output required for the application of specific and selective electric and electromagnetic signals to diseased articular cartilage in the treatment of osteoarthritis, cartilage defects due to trauma or sports injury, or used as an adjunct with other therapies (cell transplantation, tissue-engineered scaffolds, growth factors, etc.) for treating cartilage defects in the human knee joint and a device for delivering such signals to a patient's knee. An analytical model of the human knee is developed whereby the total tissue volume in the human knee may be determined for comparison to the total tissue volume of the diseased tissue in the animal model using electric field and current density histograms. The voltage and current output used in the animal model is scaled based on the ratio of the total tissue volume of the diseased tissue of the human to the total tissue volume of the diseased tissue in the animal model and the resulting field is applied to the diseased tissue of the human using at least two electrodes applied to the knee or a coil or solenoid placed around the knee. The voltage of the signal applied to the electrodes, coil or solenoid is varied based on the size of the knee joint; larger knee joints require larger voltages to generate the effective electric field.