United Monolithic Semiconductors Research Articles

Planar single and dual-resonant microwave biosensors for label-free bacteria detection

Label-free microwave resonator-type biosensors covered with polyclonal anti-Escherichia coli antibodies are presented. The sensors` construction provides high sensitivity on the bacteria detection, whereas the utilization of specific antibodies ensures selective bacteria binding. Two types of biosensors are studied to explore the benefits of microwave sensing: the first one, in which increased sensitivity on the bacteria detection is obtained due to the differential excitation of the resonating conductors, and the second one, in which a multi-resonant character increases the probability for the bacteria detection. The exemplary sensors were designed to operate in the frequency range of 4.4 – 4.8 GHz or 15 – 25 GHz and physically realized on a silicon wafer using standard microelectronic processor using the United Monolithic Semiconductor (UMS) PH25 process on a 100 µm thick GaAs substrate, respectively. The sensors were experimentally validated by measurements of various concentrations of Escherichia coli. Both types of sensors were compared to show their advantages and disadvantages in terms of future use for biomedical applications. Both biosensors were shown to enable bacteria detection at concentrations reaching as low as 103 CFU/ml. Interestingly, a monotonic response for bacteria concentration was observed for a multi-resonant sensor, which can be utilized for estimation of bacteria content using the calibration curve.

High Frequency, Low Loss, Additively Manufactured Hermetic Package

Abstract This paper presents the development of a new type of hermetic cavity package for mmWave RF MMICs. The package features an all copper additively manufactured construction for optimal thermal performance as well as low loss air coax RF signal routing with a critical ceramic feedthrough to isolate the internals of the package from the external environment. With a simulated thermal resistance of 1 C/W, from die backside to package lid, and RF insertion loss of less than 0.5dB from 0–80Ghz, this package can support high power as well as high frequency MMICS. With no polymers in the construction of the package true hermetic performance is expected, making this package a high reliability option as well. For this paper two die were selected for demo packages. These die do not have surface mountable packages offered on the market. The die selected are the CMD247 30–40GHz Low Phase Noise Amplifier from Qorvo and the CHA2080-98F 71–86GHz Low Noise Amplifier from United Monolithic Semiconductors. RF insertion loss as well as environmental reliability will be demonstrated with these devices. The additive manufacturing process used is the proprietary PolyStrata® process developed by Nuvotronics. With the development of 14” panel substrate manufacturing line utilizing a mask-less process, fabrication process can support both high-volume, and high-customization without incurring prohibitive tooling costs.

Multisection Ultra-Broadband Directional Coupler Designed in MMIC Technology

An ultra-broadband multisection directional coupler designed in Monolithic Microwave Integrated Circuit (MMIC) technology has been presented. It has been shown for the first time that it is possible to achieve bandwidths exceeding one frequency decade, simultaneously taking under account technological constrains. The proposed directional coupler is composed of three coupled-line sections having different values of electrical lengths and coupling coefficients. The strongest coupled section has been designed as an asymmetric three-strip coupled-line section, whereas the rest of the sections have been implemented as symmetric two-strip coupled-line structures. To improve electrical performance of the coupler, a compensation method has been implemented together with loss analysis which has to be considered in lossy inhomogeneous medium. The proposed 3-dB directional coupler has been designed in PH25 process based on gallium arsenide (GaAs) from United Monolithic Semiconductors (UMS), and fabricated. The measurement confirms applicability of the design method in monolithic technology for such networks operating in bandwidth exceeding one frequency decade.

Monolithic Miniaturized Differentially-Fed Branch-Line Directional Coupler in GaAs Monolithic Technology

In this paper, a design of a miniaturized branch-line directional coupler is presented. The coupler is designed with balanced coupled-line sections, which are electrically shortened by the application of lumped capacitors. To measure the parameters of the coupler, appropriate baluns have been designed. The coupler has been designed in a GaAs PH25 UMS (united monolithic semiconductor) technology with the center frequency of 24 GHz. The measured power split equals 3 dB with the transmission/coupling imbalance not exceeding 0.6 dB. The measured return losses equal 17 dB at the center frequency, whereas the isolation reaches 17 dB. The fabricated coupler‘s size equals 630 um × 487 um, which is 0.19 of the full size of the directional coupler in the chosen technology (1191 um × 1170 um).

Realization of High-Performance Broadband Quadrature Directional Couplers in UMS PH25 Technology

The problem of the realization of broadband quadrature directional couplers in UMS (United Monolithic Semiconductors) PH25 is thoroughly investigated. The limitations of the selected technology are discussed with respect to directional couplers’ design. It is shown that, in such technologies, two major problems have to be overcome to achieve the high-performance of the resulting integrated couplers, i.e., the realization of appropriate coupling together with appropriate characteristic impedances, and the equalization of inductive and capacitive coupling coefficients that are inherently different in inhomogeneous dielectric structures. Three different solutions that allow for achieving strong coupling in the selected UMS PH25 process were selected and experimentally investigated, showing the possibility of such circuits’ realization. In each of the presented integrated couplers, capacitive compensation techniques were applied for coupling coefficients’ equalization.

A Compact Sideband Separating Downconverter With Excellent Return Loss and Good Conversion Gain for the W Band

We have developed a sideband separating receiver module for the W band (75–110 GHz) that has been designed with a scalable and compact architecture allowing easy integration into larger systems, like focal plane arrays. The receiver includes a high-frequency amplification stage giving it a good conversion gain and, most importantly, due to its original architecture, excellent return losses. The latter permits, if needed, efficient incorporation of further amplification prior to mixing. The module is based on a 90° hybrid followed by an amplification stage and broadband mixers. As amplification stage, we rely on commercial low-noise amplifier chips that use the 70-nm metamorphic-high-electron-mobility process from OMMIC. The downconverter is a subharmonic mixer designed as a monolithic microwave integrated circuit and fabricated using the standard gallium-arsenide Schottky diode process from United Monolithic Semiconductor. The size of the module is 50 mm × 25 mm × 20 mm and shows good performance with an input return loss above 12 dB in the entire band, an average conversion gain of 5 dB, and sideband rejection ratio above 10 dB in the majority of the band. The primary motivation of this article has been radio astronomy, but other areas like imaging, telecommunications, or remote sensing can benefit from such compactness and integrability into multibeam systems.

A microwave matrix sensor for multipoint label-free Escherichia coli detection

This paper presents a microwave sensor designed as a capacitive matrix for label-free Escherichia coli detection. The mean value of capacitances’ change in the capacitive matrix sensor is an indicator of the bacteria detection. The theoretical analysis was confirmed by the realization of an exemplary sensor chip manufactured using the United Monolithic Semiconductor (UMS) PH25 process on a 100 μm thick GaAs substrate and measurements of various concentrations of Escherichia coli in the frequency range 1–3 GHz. The matrix topology of the sensor together with biofunctionalization of the sensor surface with polyclonal anti-Escherichia coli antibody allow to obtain high detection sensitivity on various concentrations of Escherichia coli reaching 103 CFU/ml. The obtained results are promising for future biomedical applications, in terms of specific bacteria presence detection.

S-Band GaN Single-Chip Front End for Active Electronically Scanned Array With 40-W Output Power and 1.75-dB Noise Figure

The design, realization, and tests of an S-band gallium nitride (GaN) monolithic microwave integrated circuit (MMIC) single-chip front end (SCFE) is presented. The MMIC, realized on the 250-nm gate length GaN process available from the united monolithic semiconductor, integrates high-power and low-noise amplification together with the transmit (Tx)-receive (Rx) switch in a $7\times 7$ mm2 chip area. The SCFE has been conceived for active electronically scanned antenna applications in S-band. In the Rx mode, noise figure (NF) lower than 1.75 dB and gain better than 30 dB have been measured. In the Tx mode, output power and power added efficiency better than 45 dBm and 42%, respectively, have been achieved, with an associated gain higher than 35 dB. Such performance has been measured over a 13% fractional bandwidth in S-band. To the best of the authors’ knowledge, this is the first GaN SCFE operating in S-band.

A high-power solid state amplifier for Galileo satellite system exploiting European GaN technology

This paper describes the development of an L-Band (f0= 1.575 GHz) high power and efficient solid state power amplifier (SSPA) designed for the European satellite navigation system (i.e. Galileo). The amplifier, developed in the framework of the European Project named SLOGAN, exploits the GH50-10 GaN technology available at United Monolithic Semiconductor foundry. The aim of the project is to offer, using as much as possible European technologies, a valid alternative to replace traveling wave tube amplifiers with more compact and reliable systems. All the SSPA functionalities, i.e. power supply, power conditioning and radio frequency amplification, are integrated in the developed architecture and accommodated in a single box with limited volume and mass. The required output power level is achieved by parallelizing several GaN die power bars of 12 and/or 25.6 mm. In continuous wave operating mode, the overall SSPA delivers an output power higher than 250 W at less than 2 dB of gain compression in the whole E1-band. Moreover, the registered gain and efficiency are higher than 67 dB and 54%, respectively.

A tunable and reconfigurable MMIC active filter in GaAs technology

The filter presented in this article is an active band-pass filter whose center frequency and bandwidth can be tuned. It is composed of channels inserted into a distributed structure, and the frequency agility is obtained by activating one or more of them. The concept is validated with measurements realized on a 3-channel prototype structure implemented in the United Monolithic Semiconductors (UMS) PPH25 GaAs technology from UMS. This filter is tunable throughout the X and Ku bands. This first prototype yields encouraging results: the center frequency can be tuned between 9.7 and 14 GHz, with an average gain of 10 dB throughout this range and a noise figure between 7 and 11 dB. The filter occupies 13.5 mm2 of area and consumes 10.5 mA per active stage from a 4 V supplying voltage. It is designed for wideband and agile receivers.

Design, modeling and characterization of MMIC integrated cascode cell for compact Ku-band power amplifiers

This paper reports on the design of a new power cell dedicated to Ku-band power amplifier (PA) applications. This cell called “integrated cascode” has been designed in order to propose a strong decrease in terms of circuit size for PA. The technology used relies on 0.25-μm GaAs pseudomorphic high electron mobility transistors (PHEMT) of United Monolithic Semiconductors (UMS) foundry. A distributed approach is proposed in order to model this power cell. The challenge consists of obtaining, with a better shape factor (ratio between the vertical and horizontal sizes of the transistor), the same performances than a single transistor with the same gate width. In order to design a 2W amplifier, we have used two 12 × 100 μm transistors. Cascode vertical size is 413 μm whereas a transistor with the same gate width exhibits a vertical size of 790 μm. Therefore, the shape factor is nearly one as compared to a shape factor of 4 for a classical parallel architecture. This new device allows us to decrease the Monolithic microwave integrated circuit amplifier area of 40% compared to amplifier based on single transistors.

1-6 GHz 4 W MMIC GaAs high power amplifier

This article presents the design of a monolithic high power amplifier with 4 W output power in the 1–6 GHz band (2.5 octave).The amplifier uses two gain stages composed by four and eight transistors. Power united monolithic semiconductor PPH25x process, on GaAs substrate with 70 μm thickness, has been used. The Montecarlo analysis shows a small-signal gain's average value of 24 dB and output power levels higher than 36 dBm. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2747–2751, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27208

GaAs HEMT Modeling and its Application to Active Frequency Multipliers

In this article, improved nonlinear modeling technique for microwave PHEMT is described. The accurate small-and large-signal models of HEMT, MESFET devices are used for robust designs and fabrication development. The implementation of model is done by parameter extraction as well as using Agilent’s ADS. The modeling procedure is used to extract the model of PHEMT EC2612 supplied by United Monolithic Semiconductor Inc. This model is used to design single-stage 10/20 GHz wideband frequency doubler with a maximum conversion gain of 3 dB. The doubler has 40% bandwidth over the input frequency range of 8–12 GHz. A band reject at fundamental frequency filter has been designed at output stage of doubler instead of conventional λ/2 open circuit reflector at second harmonic frequency, which is responsible for broadband operation of doubler.

Industrial GaN FET technology

GaN technology has gained a lot of attention in Europe over the last few years for various domains including RF electronics. After a few years of active observation, United Monolithic Semiconductors (UMS) has taken the decision to introduce a GaN technology family in its portfolio. Based on its extensive experience of III–V technology and the intensive support and collaboration with partners and European research institutes, UMS has developed the capability to produce state-of-the-art GaN devices and circuits. The present paper will summarize the current status achieved and illustrate it with a few representative examples. Aspects covering material, devices, and circuits will be addressed.

An High Performance Ka-band MMIC Fourth Harmonic Image Rejection Diode Mixer

An high performance Ka-band MMIC fourth harmonic image rejection diode mixer is designed using commercial United Monolithic Semiconductors (UMS) process in this paper. Details of design approach and outcome of simulations are presented. The results show that this mixer has a conversion loss less than 15.2 dB and image rejection ratio (IRR) more than 20 dB in the 34–38 GHz with a wide band IF range up to 3 GHz, for a local oscillating (LO) drive power level of 13 dBm.

An advanced low-frequency noise model of GaInP-GaAs HBT for accurate prediction of phase noise in oscillators

We present a new low-frequency noise model of a GaInP-GaAs HBT and the associated extraction process from measurements. Specific measurements enable us to locate the two dominant low-frequency noise sources. Their spectral densities extraction as a function of the emitter bias current is then performed and a normalized scalable model is deduced. The cyclostationarity of the low-frequency noise sources is justified. The whole noise model including the shot noise source is implemented in the nonlinear HBT model used in the United Monolithic Semiconductors foundry. In order to verify the validity of the scalable noise model, several voltage-controlled oscillators with different center frequencies and tuning bandwidth have been designed and processed. Comparisons between the predicted performances and experimental results show an excellent agreement and validate the proposed low-frequency noise modeling of multifinger HBTs.

A Novel Course on Microwave Monolithic Integrated Circuit Design, Theory, and Characterization

A novel course conducted for the past three years at the National University of Singapore is described. The course design projects introduce students to microwave monolithic integrated circuit (MMIC) component and subsystem design and expose them to modern computer-aided design (CAD) tools, industry standard test equipment, and procedures. In addition, since the proposed topics are industry-collaborated research projects, students gain new enthusiasm for the circuit design and directly see the importance and relevance in the engineering field. In contrast to the available MMIC courses conducted in the other universities or organizations, these students are given the complete freedom to implement the hardware within a fixed time frame. Implementation of these MMIC circuitries using external foundries, such as United Monolithic Semi-conductor (UMS), Philips Microwave Limeil (PML), and Triquint, has proven to be highly motivational and educational and, eventually, has led to increased enrollments in other higher level electromagnetic and microwave circuit modules.