Semiconductors & ICs

Ka-Band Waveguide Two-Way Hybrid Combiner for MMIC Amplifiers

This technology is applicable as a power combiner for solid-state power amplifiers (SSPAs) with unequal and arbitrary power output ratios.

The design, simulation, and characterization of a novel Ka-band (32.05±0.25 GHz) rectangular waveguide two-way branch-line hybrid unequal power combiner (with port impedances matched to that of a standard WR-28 waveguide) has been created to combine input signals, which are in phase and with an amplitude ratio of two. The measured return loss and isolation of the branch-line hybrid are better than 22 and 27 dB, respectively. The measured combining efficiency is 92.9 percent at the center frequency of 32.05 GHz. This circuit is efficacious in combining the unequal output power from two Ka-band GaAs pseudomorphic high electron mobility transistor (pHEMT) monolithic microwave integrated circuit (MMIC) power amplifiers (PAs) with high efficiency.

Posted in: Briefs, TSP, Semiconductors & ICs, Amplifiers, Integrated circuits, Waveguides, Amplifiers, Integrated circuits, Waveguides

Quad-Chip Double-Balanced Frequency Tripler

This technology has uses such as high-resolution radar and spectroscopic screening.

Solid-state frequency multipliers are used to produce tunable broadband sources at millimeter and submillimeter wavelengths. The maximum power produced by a single chip is limited by the electrical breakdown of the semiconductor and by the thermal management properties of the chip. The solution is to split the drive power to a frequency tripler using waveguides to divide the power among four chips, then recombine the output power from the four chips back into a single waveguide.

Posted in: Briefs, TSP, Semiconductors & ICs, Integrated circuits, Waveguides, Integrated circuits, Waveguides, Semiconductors

Radiation-Hardened Solid-State Drive

A method is provided for a radiationhardened (rad-hard) solid-state drive for space mission memory applications by combining rad-hard and commercial offthe- shelf (COTS) non-volatile memories (NVMs) into a hybrid architecture. The architecture is controlled by a rad-hard ASIC (application specific integrated circuit) or a FPGA (field programmable gate array). Specific error handling and data management protocols are developed for use in a rad-hard environment. The rad-hard memories are smaller in overall memory density, but are used to control and manage radiation-induced errors in the main, and much larger density, non-rad-hard COTS memory devices.

Posted in: Briefs, TSP, Semiconductors & ICs, Computer software / hardware, Computer software and hardware, Integrated circuits, Computer software / hardware, Computer software and hardware, Integrated circuits, Radiation protection

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.

Posted in: Briefs, TSP, Semiconductors & ICs, Integrated circuits, Voltage regulators, Integrated circuits, Voltage regulators, Semiconductors

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.

Posted in: Briefs, TSP, Semiconductors & ICs, Integrated circuits, Optics, Radar, Integrated circuits, Optics, Radar, Semiconductors, Noise, Noise

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.

Posted in: Briefs, TSP, Semiconductors & ICs, Design processes, Architecture, Architecture, Product development, Semiconductors

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.

Posted in: Briefs, TSP, Semiconductors & ICs, Radar, Waveguides, Radar, Waveguides, Semiconductors, Performance tests

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.

Posted in: Briefs, TSP, Semiconductors & ICs, Mathematical models, Imaging, Imaging and visualization, Integrated circuits, Imaging, Imaging and visualization, Integrated circuits

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.

Posted in: Briefs, TSP, Semiconductors & ICs, Finite element analysis, Fabrication, Alloys, Semiconductors

Low-Noise MMIC Amplifiers for 120 to 180 GHz

Potential applications include radar, communications, radiometry, and millimeter-wave imaging.

Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as prototype low-noise amplifiers (LNAs) to be incorporated into instruments for sensing cosmic microwave background radiation. There are also potential uses for such LNAs in electronic test equipment, passive millimeter-wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The main advantage afforded by these MMIC LNAs, relative to prior MMIC LNAs, is that their coverage of the 120-to-180-GHz frequency band makes them suitable for reuse in a wider variety of applications without need to redesign them. Each of these MMIC amplifiers includes InP transistors and coplanar waveguide circuitry on a 50-μm-thick chip (see Figure 1). Coplanar waveguide transmission lines are used for both applying DC bias and matching of input and output impedances of each transistor stage. Via holes are incorporated between top and bottom ground planes to suppress propagation of electromagnetic modes in the substrate.

Posted in: Briefs, TSP, Semiconductors & ICs, Amplifiers, Integrated circuits, Amplifiers, Integrated circuits

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