Monolithic Integrated Circuit Technology Research Articles

Gallium arsenide octave-bandwidth microwave voltage-controlled oscillator having discrete varicap

Modern reconfigurable communication systems demand microwave voltage-controlled oscillators (VCOs) possessing an octave-wide bandwidth. Many advanced applications require also a low phase noise and a low current consumption for such VCOs. To meet an octave-bandwidth specification in combination with a low phase noise and a low current consumption it is desirable to implement a microwave monolithic integrated circuit (MMIC) technology. In-house gallium arsenide (GaAs) MMIC technology is implemented to build VCOs in this work. At the same time, in order to achieve a high-Q wide frequency tuning range, we implemented also a discrete variable capacitance diode (varicap). The discrete varicap is stacked above MMIC oscillator chip. A vertical design structure of the discrete varicap guarantees a high overlap capacitance ratio (K>20) along with reduced affect of the parasitic reactance. A high overlap capacitance ratio is needed for an octave-wide frequency tuning, while reduced affect of the parasitic reactance increases Q-factor of the VCO resonator. Hence, a sequential integration of the discrete varicap over monolithic oscillator chip resolves referred tough challenges in the design of VCO. Integrated VCO is finally packaged as a surface-mount device (SMD). At that SMD ceramic package is sealed with the metal lid. The oscillator circuitry is based on the conventional negative resistance approach with a positive feedback realized by common-source capacitance. An active element of the oscillator is a pseudomorphic high electron-mobility transistor (pHEMT). The gate length of a transistor is 0.15 µm. The width of the gate varies from 240 µm to 360 µm depending on working frequencies of the VCO. The varicap is built on the GaAs epitaxial heterostructure having customized gradient doping profile with abrupt junction. Nonlinear behavioral model of the varicap is extracted from the diode measurements and is further used for VCO simulation. Two types of VCO have been designed, fabricated and tested. First (second) type of VCO provides a tuning range from 5 to 10 GHz (from 10 GHz to 20 GHz), respectively. The measurement results demonstrate an output power of 3.9 dBm; a current consumption of 30 mA at a supply voltage of 5 V; a phase noise of minus 90 dBc/Hz at 100 kHz offset (minus 85 dBc/Hz at 100 kHz offset) for the first (second) type of VCO, respectively.

Fabrication of a Novel GaAs Thermopile Sensor for RF Amplitude Demodulation

In this letter, a novel fabrication of straight-channel RF AM demodulator based on thermopile is presented. Its structure consists mainly of CPW line fed with AM signal, resistors and thermopiles to detect the demodulated signal. The structure is fabricated using GaAs Microwave Monolithic Integrated Circuit (MMIC) technology. Experiments are implemented and the results show that this thermopile-based demodulator is able to perform demodulation of AM signal with carrier frequency of 0.01-10 GHz and signal frequency of under 5 kHz. The influence of thermopile length on the performance is also studied and the result shows that when the thermopile length gets larger, the output amplitude of the demodulated signal gets larger, but its bandwidth gets smaller. In our scenario, the length of the thermopile can be set as 50 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$</tex-math> </inline-formula> m as a tradeoff between amplitude and bandwidth. 2022-0187

High-Efficiency D-Band Monolithically Integrated GaN SBD-Based Frequency Doubler With High Power Handling Capability

A high-efficiency <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${D}$ </tex-math></inline-formula> -band monolithically integrated GaN frequency doubler based on a pair of antiseries four-anode planar GaN Schottky barrier diodes (SBDs) has been successfully fabricated. Unlike the traditional hybrid integrated circuit technology, the monolithic integrated circuit technology has been used in the design and fabrication of GaN SBD-based frequency doubler circuits to achieve good alignment and low conversion losses. At room temperature, the experiments show that the peak conversion efficiency reaches 17.0% at 115.6 GHz under a continuous wave (CW) driving which is a critical requirement for many practical applications. The efficiency of 17.0% is the highest efficiency of GaN SBD-based multipliers at present under CW driving mode. This monolithically integrated doubler also exhibits a broadband high efficiency characteristic of more than 4.7% (−5.58 dB from 17%) across a 10% band from 109 to 121 GHz. In addition, high CW power handling capability of the proposed frequency doubler is verified. The experiments show that the frequency doubler can endure a maximum CW input power of 0.5 W.

A C-Band MEMS Frequency Discriminator With High Sensitivity and Linearity

This letter reports a C-band MEMS frequency discriminator with high sensitivity and linearity. The structure of the proposed discriminator is fabricated using GaAs Microwave Monolithic Integrated Circuit (MMIC) technology. The frequency discriminator consists of one dual-band power divider, one dual-band power combiner, one delay-line and the final MEMS thermoelectric power sensor. The purpose of the designed structure is to provide an ultra-wide working frequency band and simultaneously improve sensitivity and linearity. Both on-chip detector and packaged one are tested. S-parameter measurement illustrates good impedance matching covering 4–8 GHz. The frequency sensitivities of on-chip detector are $0.52~\mu \text{V}$ /MHz @ 17 dBm, $0.85~\mu \text{V}$ /MHz @ 20 dBm and $1.66~\mu \text{V}$ /MHz @ 23 dBm, while sensitivities of the packaged one are $0.43~\mu \text{V}$ /MHz @ 17 dBm, $0.84~\mu $ V/MHz @ 20 dBm and $1.48~\mu \text{V}$ /MHz @ 23 dBm, respectively. The experiment of response time shows that the rise time and fall time of on-chip detector are about $670~\mu \text{s}$ and $550~\mu \text{s}$ , while the corresponding times of the packaged one are about $980~\mu \text{s}$ and $730~\mu \text{s}$ .

Bent cantilever radio frequency microelectromechanical system power detector with improved linearity up to 1 W

This study reports a bent cantilever radio frequency microelectromechanical system power detector with improved linearity up to 1 W. The proposed device employs an upward bent cantilever for power detection. The novelty of this structure is that the bend of this kind in cantilever can realize the compensation for non-linear saturation at high power level effectively. As a result, the linearity will be improved on the condition of high power detection. An equivalent circuit model of mechanical principle is established to analyse the bent cantilever behaviour. The whole device is fabricated using GaAs microwave monolithic integrated circuit technology. The bent cantilever is constructed to overcome the stress gradient during deep etching releasing process. Measurement results prove the improved linearity from 100 mW to 1 W and the corresponding sensitivity is 2.8 aF/mW at 10 GHz.

A Micro-Machined Phase Discriminator With Improved Power Capacity on C-Band and X-Band

This paper reports a micro-machined phase discriminator with improved power capacity on C-band and X-band. The proposed phase discriminator is processed using GaAs microwave monolithic integrated circuit technology. First, a dual-frequency power combiner is designed to extend the working frequency band. Second, a sandwich-type thermoelectric power sensor is adopted to improve the power capacity. The unique device consequently has the advantages of ultra-wide band and high power capacity. The measurement results show good S-parameters within 6-12 GHz. The sensitivities among all measured frequency points are better than 42.3 μV/deg at 23 dBm, 82.5 μV/deg at 27 dBm, and 167.3 μV/deg at 30 dBm, respectively. What is more, the experiment of response time shows that the rise time is about 617.25 μs, while the fall time is about 304.69 μs.

Improved Dynamic Range of Microwave Power Sensor by MEMS Cantilever Beam

This letter reports a microwave power sensor with improved dynamic range based on MEMS cantilever beam. The proposed power sensor is manufactured using GaAs microwave monolithic integrated circuit (MMIC) technology. In this design, a cantilever by-pass coupling structure is adopted for high power detection, while the terminating thermoelectric sensor is utilized for low power detection. The novelty of the proposed device is that the concatenation of a cantilever beam and the thermoelectric sensor allows the ultra-high dynamic range power detection. Measurement results show that the sensitivities are 0.0315, 0.0261, and 0.0237 mV/mW at 1, 2, and 3 GHz for input power from 0.1 to 100 mW, respectively. For input power from 100 mW to 1W, the sensitivities are 2.398, 3.753, and 5.416 μV/mW at 1, 2, and 3 GHz, respectively. This compact power sensor has the potential prospect for dynamic range application.

Ka‐band RF MEMS capacitive switch with low loss, high isolation, long‐term reliability and high power handling based on GaAs MMIC technology

This study presents a Ka-band radio frequency (RF) micro electro mechanical systems (MEMS) capacitive switch with low loss, high isolation, long-term reliability and high power handling based on GaAs microwave monolithic integrated circuit (MMIC) technology. In this design, a T-matching structure is employed to realise impendence matching at ‘up-state’ by modifying the dimensions of centre signal line. Thus, the reflection loss and insertion loss are improved effectively. Measurement results show that in ‘up-state’ position, the input reflection coefficient (S11) is less than −20.4 dB with the forward transmission coefficient (S21) of better than −0.27 dB at Ka-band (27–40 GHz). At ‘down-state’, the switch is designed in a state of self-resonance to obtain high isolation. The measured isolation is better than 20 dB over Ka-band and can reach 35 dB at its self-resonant frequency of 35 GHz. The measured actuation voltage is about 36 V. The measured lifetime is at least 5.76 × 107 cycles. The measured power handling capability can reach up to 39 dBm. The proposed compact RF MEMS capacitive switch possesses excellent performances in terms of low insertion loss, high isolation, long lifetime and high power handling capability.

An X‐band RLC matched power amplifier using quasi‐MMIC technology

ABSTRACTThis article presents an RLC matched power amplifier using quasi‐MMIC technology in the X‐band. The power amplifier consists of a GaN HEMT power device and several passive components including inductors, capacitors, resistors, and transmission lines using a silicon integrated passive device (IPD) process. The standard silicon process can drive the solution to cost down compared with conventional microwave monolithic integrated circuit (MMIC) technology. This technology using silicon IPDs provides small size matching networks close to MMIC dimensions. The input matching network using the RLC matched circuit is designed to obtain broadband characteristic and gain flatness. The dimensions of input and output silicon IPD are 1.5 mm × 1.2 mm and 1.9 mm × 2.2 mm, respectively, with a thickness of only 0.15 mm. The measured results show that the quasi‐MMIC power amplifier has a P3dB of more than 38.3 dBm with a drain efficiency of more than 51.2% in the frequency range from 8.2 to 10 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2803–2807, 2015

AMiBA: BROADBAND HETERODYNE COSMIC MICROWAVE BACKGROUND INTERFEROMETRY

The Y. T. Lee Array for Microwave Background (AMiBA) has reported the first results on the detection of galaxy clusters via the Sunyaev–Zel'dovich effect. The objectives required small reflectors in order to sample large-scale structures (20'), while interferometry provided modest resolutions (2'). With these constraints, we designed for the best sensitivity by utilizing the maximum possible continuum bandwidth matched to the atmospheric window at 86–102 GHz, with dual polarizations. A novel wide-band analog correlator was designed that is easily expandable for more interferometer elements. Monolithic millimeter-wave integrated circuit technology was used throughout as much as possible in order to miniaturize the components and to enhance mass production. These designs will find application in other upcoming astronomy projects. AMiBA is now in operation since 2006, and we are in the process to expand the array from seven to 13 elements.

Demonstration and Characterization of Bipolar Monolithic Integrated Circuits in 4H-SiC

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A monolithic bipolar integrated circuit technology employing transistor–transistor logic (TTL) is demonstrated in 4H-SiC for the first time. Operating on a 15-V power supply, as required by the higher base–emitter voltage of SiC bipolar transistors, TTL inverters with a fan-out of ten exhibit high-level noise margin <formula formulatype="inline"><tex>$(\hbox{NM}_{H})$</tex></formula> of 1.5 V and low-level noise margin <formula formulatype="inline"><tex>$(\hbox{NM}_{L})$</tex></formula> of 3.9 V at room temperature. The transient response of the fabricated SiC TTL gates is also characterized. The circuits operate satisfactorily from room temperature to above 300 <formula formulatype="inline"><tex>$^{\circ}\hbox{C}$</tex></formula>, suggesting that SiC bipolar integrated circuits are promising candidates for high-temperature applications. </para>

Structure and Magnetism of Ba-Hexaferrite Films Grown on Single Crystal 6-H SiC With Graduated Interfacial MgO Buffer Layers

M-type barium hexaferrite films were processed by pulsed laser deposition on single-crystal 6-H silicon carbide substrates. MgO buffer and barrier layers were introduced to improve the film quality. Samples were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, X-ray diffraction, vibrating sample magnetometry, and ferromagnetic resonance (FMR). X-ray thetas-2thetas diffraction measurements indicated a strong (0, 0, 2n) crystallographic alignment. The magnetization of the BaM film is comparable to bulk values (4piM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> ~4320 G). A derivative power FMR linewidth of 500 Oe was measured at 55 GHz for the as-deposited films. This paper explores a potential next generation of microwave and millimeter-wave monolithic integrated circuit technology based upon a wide band-gap semiconducting material

K-band 3-D MMIC low noise amplifier and mixer using TFMS lines with ground slit

Three-dimensional (3-D) microwave monolithic integrated circuit (MMIC) technology, that incorporates slits in the ground metal, was applied to K-band low noise amplifier (LNA) and I/Q mixer to provide a low cost solution for various K-band receivers such as for P-to-P radio, WLAN, and UWB sensors. The LNA incorporates a quasicoplanar stub in the input-matching network, improving the noise figure by 1 dB. This low-noise amplifier (LNA) exhibits a noise figure of 2.5 dB with an associated gain of 16 dB and an area of 0.75/spl times/0.65 mm/sup 2/. The I/Q resistive mixer incorporates a broadside 3-dB coupler with a 22-/spl mu/m-wide slit in the ground metal beneath the coupled thin-film micro-strip (TFMS) lines (patent pending). The insertion loss of the 3 dB coupler is 0.75 dB. The I/Q mixer exhibits a conversion loss of less than 14 dB at 0.1-2.0GHz IF frequencies for 2-dBm local input power. These LNA and mixer potentially make it easier to integrate receiver functions in a die.

Two-step metalorganic chemical vapor deposition growth of piezoelectric ZnO thin film on SiO2/Si substrate

Piezoelectric ZnO thin films deposited on semiconductor substrates are used for surface and bulk acoustic wave and devices, which offer advantages such as low power consumption, circuit miniaturization, and cost reduction by integration with microwave monolithic integrated circuit technology. Furthermore, temperature compensated surface acoustic wave (SAW) devices, which are attractive for both communication and sensor technologies, may be achieved in the ZnO/SiO2/Si system as ZnO and Si have positive temperature coefficients of delay, while SiO2 has a negative one. In the present work, ZnO thin films were grown on SiO2/Si substrates by metalorganic chemical vapor deposition. The structural properties of the films were investigated using x-ray diffraction, scanning electron microscopy, and scanning probe microscopy. A two-step growth process was developed to obtain ZnO films with both good crystalline quality and surface morphology. The SAW properties of the ZnO/SiO2/Si system were investigated through modeling and computer simulation based on the transfer matrix method. Acoustic velocity dispersion data obtained from measurement on testing structures agree well with the dispersion curves predicted by computer simulation. The results show that the ZnO/SiO2/Si system is promising for fabricating low-loss SAW devices.

Performance of millimeter-wave GaInP IMPATT device at elevated temperature

GaInP material has high breakdown electric fields, and thus is suitable for avalanche transit-time device application. Millimeter-wave GaInP IMPATT devices at operating temperature (500 K) are analyzed by a large-signal model in this letter. The simulation confirms that a GaInP IMPATT device has a power density advantage when compared to conventional GaAs and Si IMPATT devices. The improvement in power density is about factor of 4 at 100 GHz. Moreover, GaInP IMPATT devices are easy to incorporate into GaAs millimeter-wave monolithic integrated circuit technology because of the lattice match and high etching selectivity between GaInP and GaAs materials. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 20: 422–424, 1999.

Multifunctional radar sensor for automotive application

A multifunctional radar system for vehicles consisting of two modules with a combined bistatic/monostatic arrangement is presented. One module acts as a transceiver, whereas the other is a receiving circuit. The transmitting part radiates a frequency-modulated signal alternately in two orthogonal polarizations. The receiving parts work with different local oscillator (LO) frequencies and detect both polarizations of the scattered signal simultaneously. From the resulting Doppler spectra and a distance measurement, the velocity, tilt angle, height with respect to ground, and the direction of the movement of a vehicle can be derived. From the polarimetric information, a classification of the road condition is possible. In a first approach, the sensor was built in a conventional waveguide technique. The second step was to realize the millimeter-wave circuits of both modules with monolithic silicon millimeter-wave integrated circuit (SIMMWIC) technology. To achieve a flat arrangement, a leaky-wave antenna is developed and coupled to the SIMMWIC's.

SIMMWIC rectennas on high-resistivity silicon and CMOS compatibility

Rectifying antennas (rectennas) are realized on high-resistivity silicon substrates using silicon monolithic millimeter-wave integrated circuit (SIMMWIC) technology. Monolithically integrated coplanar Schottky barrier diodes are used as rectifying elements embedded in different antenna structures. Both p- and n-type Schottky barrier diodes are realized with cutoff frequencies up to 1 THz. The rectennas are combined with a CMOS preamplifier mounted as a multichip module (MCM) next to the rectenna on a high-resistivity silicon substrate. An amplification of 32 dB is measured. Maximum sensitivity of the detector circuit including preamplification is 1600 mV/mW/spl middot/cm/sup -2/ at 94.6 GHz. For a monolithic integration of high-frequency circuits with low-frequency control and signal-processing electronics, the monolithic integration of CMOS circuitry on high-resistivity silicon is discussed.

Active MMIC wideband time delay

In this letter, we show how active elements can be effectively employed in the design of an important microwave time delay. We present analytical and computer-simulated results for an active time delay, and layout design using microwave monolithic integrated circuit (MMIC) technology. © 1997 John Wiley & Sons, Inc. Microwave Opt Technol Lett 16: 382–385, 1997.

Prospects for terahertz technology

Addresses the prospects for terahertz technology in the context of satisfying the requirements for future communication systems and considers circuits and devices suitable for operation in this frequency regime. It examines the state-of-the-art in semiconductor device technology for terahertz applications and the prospects for monolithic integrated circuit technology at frequencies above 100 GHz. The author mentions the application to wireless LANs in particular.

Design of compact monolithic dielectric-filled metal-pipe rectangular waveguides for millimetre-wave applications

The designs of two dielectric-filled metal-pipe rectangular waveguide structures are presented which are both compatible with monolithic-integrated circuit technology. The first design uses ultralow-loss materials while the second employs materials that were available at the time. The measured performances of an experimental 105 GHz proof-of-concept π-network clearly demonstrates that the dominant TE10 mode of propagation is supported in this uniplanar technology.