Abstract: A system and method for continuous glucose monitoring (CGM) of blood in a blood vessel of a patient using a non-invasive sensor composed of a patch antenna operating in the Industrial, Scientific and Medical (ISM) Radio band (5.725 GHz-5.875 GHz). The device determines the blood glucose concentration of the blood in the blood vessel based on the measured shift of the resonant frequency of the non-invasive antenna patch sensor. A radio frequency (RF) synthesizer is used to drive the patch antenna with a fraction of its output coupled to both the antenna and receiver through a directional coupler. In this approach both the transmitted (FWD) and received (REV) power are processed, by demodulating logarithmic amplifiers, which convert the RF signals to corresponding voltages for downstream processing. The resulting voltages are then fed into a microcontroller and the measured shift in resonant frequency is converted to a real-time glucose concentration.

Abstract: A passive sensing continuous glucose monitoring system and method of use thereof. The system includes a passive antenna formed of biocompatible silicon carbide (SiC), modeled to a desired frequency, which is permanently implanted subcutaneously. The system further includes an external-to-the-body transmitting antenna to detect changes in the blood glucose level by sending a radio signal at the frequency of the implanted passive antenna into the body. This signal is received and reflected by the passive antenna, and the reflected signal is then received at an external-to-the-body receiving antenna. Changes in the glucose level lead to modifications in the signal and can be used to determine the blood glucose level externally.

Abstract: A system and method for continuous glucose monitoring (CGM) of blood in a blood vessel of a patient using a non-invasive sensor composed of a patch antenna operating in the Industrial, Scientific and Medical (ISM) Radio band (5.725 GHz-5.875 GHz). The device determines the blood glucose concentration of the blood in the blood vessel based on the measured shift of the resonant frequency of the non-invasive antenna patch sensor. A radio frequency (RF) synthesizer is used to drive the patch antenna with a fraction of its output coupled to both the antenna and receiver through a directional coupler. In this approach both the transmitted (FWD) and received (REV) power are processed, by demodulating logarithmic amplifiers, which convert the RF signals to corresponding voltages for downstream processing. The resulting voltages are then fed into a microcontroller and the measured shift in resonant frequency is converted to a real-time glucose concentration.

Abstract: In one embodiment, an implantable biosensor includes a sense antenna comprising a silicon carbide substrate and a radiating electrode formed on the substrate.

Abstract: Field effect devices, such as capacitors and field effect transistors, are used to interact with neurons. Cubic silicon carbide is biocompatible with the neuronal environment and has the chemical and physical resilience required to withstand the body environment and does not produce toxic byproducts. It is used as a basis for generating a biocompatible semiconductor field effect device that interacts with the brain for long periods of time. The device signals capacitively and receives signals using field effect transistors. These signals can be used to drive very complicated systems such as multiple degree of freedom limb prosthetics, sensory replacements, and may additionally assist in therapies for diseases like Parkinson's disease.

Abstract: An implantable magnetic resonant imaging (MRI) safe stylus for biomedical devices is described. In one example, the stylus includes a set of stylus modules. One or more of the stylus modules includes a core rod formed of silicon carbide (SiC) material, a recording array mounted on the core rod, and a stimulation array mounted at a distal end of the core rod. The stylus also includes a hemispherical cap formed of SiC material. In part due to the construction and choice of materials used in the stylus, it does not substantially couple with electromagnetic fields during an MRI, for example. Therefore, the stylus does not produce excessive additional heat. The designs described herein also rely on the high thermal transport but low heat capacity of SiC to provide a thermal pathway which will conduct induced heat throughout the stylus, to dissipate heat more evenly.

Abstract: An implantable magnetic resonant imaging (MRI) safe stylus for biomedical devices is described. In one example, the stylus includes a set of stylus modules. One or more of the stylus modules includes a core rod formed of silicon carbide (SiC) material, a recording array mounted on the core rod, and a stimulation array mounted at a distal end of the core rod. The stylus also includes a hemispherical cap formed of SiC material. In part due to the construction and choice of materials used in the stylus, it does not substantially couple with electromagnetic fields during an MRI, for example. Therefore, the stylus does not produce excessive additional heat. The designs described herein also rely on the high thermal transport but low heat capacity of SiC to provide a thermal pathway which will conduct induced heat throughout the stylus, to dissipate heat more evenly.

Abstract: An implantable neuronal prosthetic and method of manufacture thereof includes at least one elongated electrode shank adapted for arrangement in the brain having at least one electrode contact disposed on its surface and arranged to electrically couple with said brain. The at least one elongated electrode shank is formed form a single crystal cubic silicon carbide. An insulation layer of amorphous, polycrystalline, or single crystal silicon carbide is disposed over the elongated electrode shank; the insulation layer of amorphous, polycrystalline, or single crystal silicon carbide is removed from the at least one electrode contact. Signal control electronics are attached to the at least one elongated electrode shank and are in electrical communication with the at least one electrode contact. In an embodiment, a plurality of the at least one elongated electrode shanks are arranged into a matrix.

Abstract: In one embodiment, an implantable biosensor includes a sense antenna comprising a silicon carbide substrate and a radiating electrode formed on the substrate.

Abstract: Field effect devices, such as capacitors and field effect transistors, are used to interact with neurons. Cubic silicon carbide is biocompatible with the neuronal environment and has the chemical and physical resilience required to withstand the body environment and does not produce toxic byproducts. It is used as a basis for generating a biocompatible semiconductor field effect device that interacts with the brain for long periods of time. The device signals capacitively and receives signals using field effect transistors. These signals can be used to drive very complicated systems such as multiple degree of freedom limb prosthetics, sensory replacements, and may additionally assist in therapies for diseases like Parkinson's disease.

Abstract: Graphene, can be used to make an implantable neuronal prosthetic which can be indefinitely implanted in vivo. Graphene electrodes are placed on a 3C—SiC shank and electrical insulation is provided by conformal insulating SiC. These materials are not only chemically resilient, physically durable, and have excellent electrical properties, but have demonstrated a very high degree of biocompatibility. Graphene also has a large specific capacitance in electrolytic solutions as well as a large surface area which reduces the chances for irreversible Faradaic reactions. Graphene can easily be constructed on SiC by the evaporation of Si from the surface of that material allowing for mechanically robust epitaxial graphene layers that can be fashioned into electrodes using standard lithography and etching methods.

Abstract: The microfabricated prosthetic device uses local, direct, and wavelength-specific optical stimulation to achieve an action potential from a single or small group of neurons within the central nervous system (CNS). The device is biocompatible, mechanically flexible, and optically transparent. The device can also use integrated electrodes for additional input/output (IO) locations, signal verification, feedback, wireless communication, and characterization of the electrochemically-evoked potential received from the activated neuron. The purpose of the device is to act as a neural interface prosthetic. The prosthetic is designed as the central component of a brain machine interface (BMI).

Abstract: Graphene, can be used to make an implantable neuronal prosthetic which can be indefinitely implanted in vivo. Graphene electrodes are placed on a 3C—SiC shank and electrical insulation is provided by conformal insulating SiC. These materials are not only chemically resilient, physically durable, and have excellent electrical properties, but have demonstrated a very high degree of biocompatibility. Graphene also has a large specific capacitance in electrolytic solutions as well as a large surface area which reduces the chances for irreversible Faradaic reactions. Graphene can easily be constructed on SiC by the evaporation of Si from the surface of that material allowing for mechanically robust epitaxial graphene layers that can be fashioned into electrodes using standard lithography and etching methods.

Abstract: An automated, non-destructive anhysteretic magnetization characterization method for studying and modeling soft magnetic materials. This measurement method employs a “reading-waveform” that allows multiple points of reference to be established in tracing out the B waveform. In using the reference values from this waveform, the components of B that cannot be measured directly may be calculated with precision. In turn, the initial magnitude of the B waveform is identified as the unknown component of the anhysteretic state. The processes can be repeated for different values of static fields as well as a function of temperature to produce a family of anhysteretic magnetization curves. The core characterization was performed without physically altering the core, so that the true anhysteretic magnetization curve, and the true B-H loop under applied bias H, is measured.

Abstract: An implantable neuronal prosthetic and method of manufacture thereof includes at least one elongated electrode shank adapted for arrangement in the brain having at least one electrode contact disposed on its surface and arranged to electrically couple with said brain. The at least one elongated electrode shank is formed form a single crystal cubic silicon carbide. An insulation layer of amorphous, polycrystalline, or single crystal silicon carbide is disposed over the elongated electrode shank; the insulation layer of amorphous, polycrystalline, or single crystal silicon carbide is removed from the at least one electrode contact. Signal control electronics are attached to the at least one elongated electrode shank and are in electrical communication with the at least one electrode contact. In an embodiment, a plurality of the at least one elongated electrode shanks are arranged into a matrix.

Abstract: A method and device produced for design, construction, and use of integrated circuits in wide bandgap semiconductors, including methods for fabrication of n-channel and p-channel junction field effect transistors on a single wafer or die, such that the produced devices may have pinchoff voltages of either positive or negative polarities. A first layer of either p-type or n-type is formed as a base. An alternating, channel layer of either n-type or p-type is then formed, followed by another layer of the same type as the first layer. Etching is used to provide contacts for the gates, source, and drain of the device. In one variation, pinchoff voltage is controlled via dopant level and thickness the channel region. In another variation, pinchoff voltage is controlled by variation of dopant level across the channel layer; and in another variation, pinchoff voltage is controlled by both thickness and variation of dopant level.

Abstract: A method and device produced for design, construction, and use of integrated circuits in wide bandgap semiconductors, including methods for fabrication of n-channel and p-channel junction field effect transistors on a single wafer or die, such that the produced devices may have pinchoff voltages of either positive or negative polarities. A first layer of either p-type or n-type is formed as a base. An alternating, channel layer of either n-type or p-type is then formed, followed by another layer of the same type as the first layer. Etching is used to provide contacts for the gates, source, and drain of the device. In one variation, pinchoff voltage is controlled via dopant level and thickness the channel region. In another variation, pinchoff voltage is controlled by variation of dopant level across the channel layer; and in another variation, pinchoff voltage is controlled by both thickness and variation of dopant level.

Abstract: Devices and methods for fabricating wholly silicon carbide heterojunction bipolar transistors (HBTs) using germanium base doping to produce suitable emitter/base heterojunctions. In one variation, all device layers are are grown epitaxially and the heterojunction is created by introducing a pseudoalloying material, such as germanium, to form a graded implant. In other variations, the device epitaxial layers are 1) grown directly onto a semi-insulating substrate, 2) the semi-insulating epitaxial layer is grown onto a conducting substrate; 3) the subcollector is grown on a lightly doped p-type epitaxial layer grown on a conducting substrate; and 4) the subcollector is grown directly on a conducting substrate. Another variation comprises a multi-finger HBT with bridging conductor connections among emitter fingers. Yet another variation includes growth of layers using dopants other than nitrogent or aluminum.

Abstract: Devices and methods for fabricating wholly silicon carbide heterojunction bipolar transistors (HBTs) using germanium base doping to produce suitable emitter/base heterojunctions. In one variation, all device layers are are grown epitaxially and the heterojunction is created by introducing a pseudoalloying material, such as germanium, to form a graded implant. In other variations, the device epitaxial layers are 1) grown directly onto a semi-insulating substrate, 2) the semi-insulating epitaxial layer is grown onto a conducting substrate; 3) the subcollector is grown on a lightly doped p-type epitaxial layer grown on a conducting substrate; and 4) the subcollector is grown directly on a conducting substrate. Another variation comprises a multi-finger HBT with bridging conductor connections among emitter fingers. Yet another variation includes growth of layers using dopants other than nitrogent or aluminum.

Abstract: A photoconductive spread-spectrum communications system that includes a tsmitter and a receiver. The transmitter includes an oscillating laser, a Pockels' cell, a delay cell, a photoconductive switch, and an antenna for transmitting an electromagnetic spread-spectrum signal. The receiver includes an oscillating laser, a Pockels' cell, an antenna for receiving a spread-spectrum signal, a photoconductive switch, a filter, and a threshold detector for regenerating the signal contained within the spread-spectrum transmission.