This work present a new approach to design and fabrication of AlGaN/GaN based SAW-HEMT structures be applied for chemical gas sensors operating in harsh environment. A direct on-chip integrated compatibility the process technology surface acoustic wave (SAW) structure high electron mobility transistor (HEMT) was demonstrated. It enabled integrate two different principles sensing on both SAW HEMT. The functionality types HEMT device investigated. measured amplitude characteristics revealed...

This work presents the process technology and high frequency analysis of AlGaN/GaN based SAW (Surface Acoustic Wave) – HEMT (High Electron Mobility Transistor) devices to be applied for chemical gas sensors operating in GHz range. For that purpose, interdigital transducers (IDTs) device with submicrometer finger width spacing were designed improve sensor detection sensitivity. The signal processing electronics containing microwave oscillator was designed, simulated successfully tested....

In this work we demonstrate the fabrication process and electrical characterization of GaN/SiC heterostructure-based surface acoustic wave filters for highly-sensitive hydrogen sensors. propagation path, palladium metal is used as a sensing layer. The influence layer on SAW velocity measured. impact second-order effects filter properties discussed. Two different interdigitated transducer (IDT) topologies are investigated in order to achieve low insertion loss high attenuation triple transit...

The paper reports microwave properties of AlGaN/GaN HEMT fabricated on sapphire substrate. measured transition frequency as well maximum oscillation was taken a figure merit for comparison influence different treatment. Using 2μm length gate electrode 7.425 GHz 23.437 achieved. Significant surface plasma treatment found.

The paper reports high temperature on-wafer microwave characterization setup for AlGaN/GaN HEMT devices. S-parameters were measured in frequency range up to 40 GHz wide bias point settings as well parameters f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> and xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> visualized the from room 425°C. Significant influence of on properties was observed.

MSM photodetectors are investigated by measurement and modelling in microwave region. Cut-off frequencies compared for different structures layouts. Significant improvement of 2-DEG MSM's frequency response on low operating voltages was found.

A growing thirst for highly sensitive and sufficiently selective sensors extremely harsh conditions can be seen. This fact excludes the use of conventional sensing devices gives a space Surface Acoustic Wave with monolithically-integrated electronics. We have chosen AlGaN/GaN material as suitable due to its excellent chemical inertness stability piezoelectric parameters. In this paper we test possible HEMT transistor/SAW transducer monolithic integration propose design an oscillator based on SAW.

The improved dc and microwave properties of 2 mum gate length AlGaN/GaN based HEMT structures were observed after applying a novel approach in the forming Schottky interface. new uses shallow recess-gate plasma etching AlGaN barrier layer combination with "in-situ" SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> surface treatment under gate. A significant improvement both current gain cut-off frequency (f...

Progress in integrated photonics enables development of circuits with new unique properties, the future, and overcomes current limits information communication technologies. The packaging photonic is necessary for taking them out research laboratories into real implementation technology applications. Telecom optical fibers are still being best transmission medium digital data analogue signals long distance effective coupling radiation between telecom fiber ten microns core dimension...

Progress in integrated photonics enables development of circuits (PIC) with new unique properties and overcomes current limits information communication technologies. The effective coupling optical radiation between telecom fiber photonic is necessary. To address these challenges, we present our concept circuit fully customized packaging microwave, direct current, array ports automated active alignment system. Automated adjustment single-mode (SMF) arrays 8 fibers to PIC based on the...

The design, fabrication and characterization of microwave transmission structure on thin composite semiconductor/dielectric substrate technologically compatible with pseudomorphic HFETs for a micromechanical transmitted power sensor are discussed.

A new micromachining technology of mechanically fixed and thermally insulated cantilevers, bridges islands was developed to be used for design GaAs heterostructure based microelectromechanical systems (MEMS) devices. Based on the technology, two different MEMS devices were designed analyzed. The first one micromechanical thermal converter (MTC) second a coplanar waveguide (MCPW). basic electro‐thermal as well microwave properties are investigated. results obtained also supported by...

GaAs MSM photodetectors with AlAs/GaAs DBR structures designed for an operating wavelength of 840 nm were characterized in the frequency and time domains. The response MSMs, using a lightwave set-up HP8408 network analyzer, was measured. photodetector to optical pulse fast laser diode excitation evaluated. 3-dB bandwidth excess 4 GHz obtained. Frequency responses dependence on bias characterized.

The paper reports high temperature on-wafer microwave characterization setup for AlGaN/GaN HEMT devices. DC output characteristics as well parameters f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> and xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> were measured visualized in the form of 3-D diagrams range from room up to 425°C. Significant influence on properties was observed.

We present a new modified approach in the forming of interdigital transducers (IDTs) on AlGaN/GaN heterostructure fully compatible with process technology HEMTs. The uses shallow recess-gate plasma etching AlGaN barrier layer combination "in-situ" SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> surface treatment under Schottky gate fingers IDTs. It enables to excite acoustic wave (SAW) without any high external bias voltages needed...

The paper reports the properties of AlGaN/GaN HEMT fabricated on sapphire substrate. Using 2μm length gate electrode 6.67GHz transition frequency as well 24.5GHz maximum oscillation was achieved. Small-signal model identified. transistor transconductance is in range 170mS/mm. However intended for structure and technology verification, it could be used RF circuits. To improve HEMT's microwave properties, source-drain distance shortening are progress.