Semiconductors & ICs

Reconfigurable, Bi-Directional Flexfet Level Shifter for Low- Power, Rad-Hard Integration

These level shifters enable the development of multi-level voltage systems.Two prototype Reconfigurable, Bidirectional Flexfet Level Shifters (ReBiLS) have been developed, where one version is a stand-alone component designed to interface between external low voltage and high voltage, and the other version is an embedded integrated circuit (IC) for interface between internal low-voltage logic and external high-voltage components. Targeting stand-alone and embedded circuits separately allows optimization for these distinct applications. Both ReBiLS designs use the commercially available 180-nm Flex - fet Inde pend ently Double-Gated (IDG) SOI CMOS (silicon on insulator, complementary metal oxide semiconductor) technology.

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Compact, Miniature MMIC Receiver Modules for an MMIC Array Spectrograph

MMIC multi-chip modules can be used in astrophysics telescopes, automotive radar, and communication links.A single-pixel prototype of a W-band detector module with a digital backend was developed to serve as a building block for large focal-plane arrays of monolithic millimeter-wave integrated circuit (MMIC) detectors. The module uses low-noise amplifiers, diode-based mixers, and a WR10 waveguide input with a coaxial local oscillator. State-of-the-art InP HEMT (high electron mobility transistor) MMIC amplifiers at the front end provide approximately 40 dB of gain. The measured noise temperature of the module, at an ambient temperature of 300 K, was found to be as low as 450 K at 95 GHz.

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Magnetic-Field-Tunable Superconducting Rectifier

This device would be useful in superconducting circuit applications.Superconducting electronic components have been developed that provide current rectification that is tunable by design and with an externally applied magnetic field to the circuit component. The superconducting material used in the device is relatively free of pinning sites with its critical current determined by a geometric energy barrier to vortex entry. The ability of the vortices to move freely inside the device means this innovation does not suffer from magnetic hysteresis effects changing the state of the superconductor.

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Waveguide Transition for Submillimeter-Wave MMICs

An integrated waveguide-to-MMIC (monolithic microwave integrated circuit) chip operating in the 300-GHz range is designed to operate well on highpermittivity semiconductor substrates typical for an MMIC amplifier, and allows a wider MMIC substrate to be used, enabling integration with larger MMICs (power amplifiers). The waveguide-to- CBCPW (conductor-backed coplanar waveguide) transition topology is based on an integrated dipole placed in the Eplane of the waveguide module. It demonstrates low loss and good impedance matching. Measurement and simulation demonstrate that the loss of the transition and waveguide loss is less than 1-dB over a 340-to-380-GHz bandwidth.

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Lattice-Matched Semiconductor Layers on Single Crystalline Sapphire Substrate

Rhombohedrally grown lattice-matched semiconductor alloys can be used in photovoltaic solar cells and photon detectors. SiGe is an important semiconductor alloy for high-speed field effect transistors (FETs), high-temperature thermoelectric devices, photovoltaic solar cells, and photon detectors. The growth of SiGe layer is difficult because SiGe alloys have different lattice constants from those of the common Si wafers, which leads to a high density of defects, including dislocations, micro-twins, cracks, and delaminations.

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Hardware Implementation of a Bilateral Subtraction Filter

Modules like this one are necessary for real-time stereoscopic machine vision. A bilateral subtraction filter has been implemented as a hardware module in the form of a field-programmable gate array (FPGA). In general, a bilateral subtraction filter is a key subsystem of a high-quality stereoscopic machine vision system that utilizes images that are large and/or dense. Bilateral subtraction filters have been implemented in software on general-purpose computers, but the processing speeds attainable in this way — even on computers containing the fastest processors — are insufficient for real-time applications. The present FPGA bilateral subtraction filter is intended to accelerate processing to real-time speed and to be a prototype of a link in a stereoscopic-machine-vision processing chain, now under development, that would process large and/or dense images in real time and would be implemented in an FPGA.

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Three MMIC Amplifiers for the 120-to-200 GHz Frequency Band

These would complement previously reported MMIC amplifiers designed for overlapping frequency bands. Closely following the development reported in the article, "Low-Noise MMIC Amplifiers for 120 to 180 GHz" (NPO-42783), three new monolithic microwave integrated circuit (MMIC) amplifiers that would operate in the 120-to-200- GHz frequency band have been designed and are under construction at this writing. The active devices in these amplifiers are InP high-electron-mobility transistors (HEMTs). These amplifiers (see figure) are denoted the LSLNA150, the LSA200, and the LSA185, respectively.

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