Combining yield optimization with circuit level electromagnetic simulation (MMIC design)

This research presents an optimization study of a 5 GHz Monolithic Microwave Integrated Circuit (MMIC) design using Particle Swarm Optimization (PSO). MMIC Low Noise Amplifier (LNA) is a type of integrated circuit device used to capture signal operating in the microwave frequency. This project consists of two stages: implementation of PSO using MATLAB and simulation of MMIC design using Advanced Design System (ADS). PSO model that mimics the biological swarm behavior is developed to optimize the MMIC design variables in order to achieve the required circuit performance and specifications such as power gain, noise figure, drain current and circuit stability factor. Simulation results show that the proposed MMIC design fulfills the circuit stability factor and achieves a power gain of 19.73dB, a noise figure of 1.15 dB and a current of 0.0467A.

The truth model is introduced as the first implementation of a statistically validated GaAs FET simulation model. The authors examine the power and accuracy of the truth model by comparing the predicted and measured statistical response of a GaAs monolithic microwave integrated circuit (MMIC) 0.5-2.5 GHz amplifier. By design centering a small-signal amplifier both with and without the use of the truth model, it is shown that both yield estimates and the design center are affected by the accuracy of the device statistical model. >

The reentrant mode TEM (transverse electromagnetic) coupling method allows the MMIC (monolithic microwave integrated circuit) design engineer to fabricate low loss couplers on either GaAs or Al/sub 2/O/sub 3/ substrates without the problems encountered in fabricating long fine-line structures. In addition, since the odd mode energy is mainly contained in a high-dielectric region rather than in air, the even and odd mode velocities are closely matched, thus enabling the coupler to exhibit excellent VSWR (voltage standing wave ratio) and differential phase performance. Because of the excellent coupler performance and design flexibility obtained with this technique, coupled structures which used to require multilayer stripline or suspended substrate approaches can now be easily fabricated and integrated with conventional MIC (microwave integrated circuit) circuitry. The technique also allows the MMIC designer to fabricate very tightly coupled structures without the problems encountered with fine-line lithography. >

In this work, a short wavelength microstrip line employing periodically arrayed capacitive elements (PACE) on GaAs monolithic microwave integrated circuit (MMIC) was developed for application to miniaturized on-chip passive components. The microstrip line employing PACE showed a wavelength much shorter than conventional transmission line. Concretely, the wavelength of the microstrip line employing PACE was only 10 % of conventional microstrip line on GaAs MMIC. Using the microstrip line employing PACE, a highly miniaturized impedance transformer was fabricated on GaAs MMIC. The impedance transformer showed good RF performances in a broad band from S to X band. Concretely, the return and insertion loss are −28 and −1.4 dB, respectively, at a center frequency of 7 GHz, and return loss values better than −10 dB were observed from 3.2 to 9.2 GHz, and insertion loss values of −1.5 ± 0.5 dB were observed in the above frequency range. The size of the impedance transformer was 0.042 mm2, which is 0.95 % of the size of the conventional transformer on MMIC.

Technological solutions are presented for forming interconnect metallization of GaAs monolithic microwave integrated circuits (MMICs) based on the W/Cu/WN x thin-film composition. A peculiarity of these solutions is that, for the first time, copper conductors with the surface completely surrounded by layers of diffusion barriers are created using the liftoff method traditionally employed for producing GaAs MMICs. Copper conductors 380 nm thick were deposited by E-beam evaporation, while the layers of planar and sidewall diffusion barriers based on W and WN x were sputtered. For successful formation of the sidewall diffusion barriers on the vertical surfaces of the copper conductors, the profile optimization of the photoresist mask was carried out. Modes of removing the photoresist mask are presented that enable effective elimination of the metallic “veils” formed on the vertical walls of the photoresist mask in the process of sputtering of diffusion barriers. The interconnects W/Cu/WN x were integrated into the manufacturing process of GaAs microwave low-noise amplifiers based on the pHEMT with 250 nm T-gates.

This paper presents a power amplifier (PA) Monolithic Microwave Integrated Circuit (MMIC) based on GaN High Electron Mobility Transistor (HEMT) at 110 GHz. A parallel cascade class AB power amplifier is used in order to increase linearity and efficiency. This single-ended three-stage power amplifier provides 19.6dBm output power (Pout) with large signal gain of 7.6dB and power added efficiency (PAE) of 5.7% at 110GHz. The proposed power amplifier exhibits output power of 18.7dBm at 1dB compression point (P 1dB ).

The design and performance of a two-stage MMIC (monolithic microwave integrated circuit) power amplifier that has established new benchmarks for power output, bandwidth, and efficiency are reported. The amplifier produces 22 W+or-1.4 dB from 3.0 to 6.0 GHz, with a maximum power output of 29 W, a minimum of 15 W, an associated power gain of 10 to 13.5 dB, and a power-added efficiency of 23% to 35%. The results rival the best narrowband results reported using multiple discrete MESFET cells in a hybrid MIC internally matched format. This excellent performance can be attributed to an accurate device model, a comprehensive design methodology, a robust matching circuit topology, and a high-yield/high-performance power MMIC processes. >

[Abstract] Regressive equations that calculate the maximum channel temperature of a GaAs monolithic microwave integrated circuit (MMIC) have been made through a lot of finite element (FE) analyses. And this paper suggests how to estimate the maximum channel temperature with those regressive equations for frequent cases. As an example, a medium power amplifier’s maximum channel temperature was calculated and its result was larger than that of a complete FE model by about 4%. The medium power amplifier’s temperature distribution was obtained through an infrared scan and, even though the maximum channel temperature could not be obtained due to the test’s inherent shortcoming, temperature other than gate fingers showed good agreement with FE analysis results. Therefore it can be said that the practical method for obtaining the maximum channel temperature using regressive equations can give thermal resistance of a GaAs MMIC very easily and quickly without time-consuming FE analyses.

The coplanar waveguide (CPW) gap discontinuity is an important component of many applications in the monolithic microwave integrated circuits (MMICs). Therefore, accurate modeling of the CPW gap discontinuity is very important and fundamental for the design of MMICs. In this work, a new lumped equiva1ent-circuit model which can accurately describe the characterization of the CPW gap discontinuity from 0 to 150 GHz is proposed. The parameters are extracted from electromagnetic (EM) simulations simply and conveniently without any complicated optimization algorithms. And we make the model scalable in gap length, width and space. Satisfactory fitting accuracy is obtained between the model data and EM simulations, which verifies that our model can be implemented in computer-aided design software to reduce design time and save computer resources.

GaAs microwave monolithic integrated circuits (MMICs) with Ba1−XSrXTiO3 (BST) capacitors have been developed. Spin-coating of sol-gel solution was used to make the BST thin film. The obtained BST film has a dielectric constant of 300 that is 50 times higher than the conventional SiN one. The capacitance has the frequency roll-off over 2 GHz, which is sufficient enough for a variety of consumer applications. The implemented GaAs MMICs with on-chip BST capacitors enable the positive-bias supply and high gain performance as well as the small package outline.

Future communications satellites are likely to use gallium arsenide (GaAs) monolithic microwave integrated-circuit (MMIC) technology in most, if not all, communications payload subsystems. Multiple- scanning beam antenna systems are expected to use GaAs MMIC's to increase functional capability, to reduce volume, weight, and cost, and to greatly improve system reliability. RF and IF matrix switch technology based on GaAs MMIC's is also being developed for these reasons. MMIC technology, including gigabit-rate GaAs digital integrated circuits, offers substantial advantages in power consumption and weight over silicon technologies for high-throughput, on-board baseband processor systems. In this paper, current developments in GaAs MMIC technology are described,and the status and prospects of the technology are assessed.

A bond-wire-free interconnection between monolithic microwave integrated circuit (MMIC) and antenna using a stacked patch configuration is investigated. An edge-fed patch on a gallium arsenide (GaAs) MMIC chip drives a patch antenna integrated in the lid of the MMIC package. The lid is formed using a liquid crystal polymer (LCP) substrate. The first implementation using a laminated multichip module (MCM-L) process is presented that covers the designated E-band spectrum for long-range wireless communications (71–86 GHz). Electromagnetic simulations and measurements of antenna radiation patterns agree well over the whole frequency range of interest. Important design aspects and manufacturing tolerances specific for the implementation of the interface in MCM-L millimeter-wave front-ends are presented. An alternative design is proposed for improved radiation patterns across the band.

Experimental models of several grounded coplanar waveguide discontinuity structures, such as series and shunt inductors and capacitors, have been developed using experimental measurements and computer optimization. The equivalent circuit models have been derived in terms of structural parameters of the discontinuity structures to facilitate their easy use in the design of coplanar MMICs (monolithic microwave integrated circuits). These simple models can be integrated with any simulation program to facilitate their easy use. >

In this article, we propose a matching network design algorithm based on the segmentation of the real and imaginary part of optimum source impedance curve with respect to space variable x and frequency ω , respectively. The impedance curve (comprising of real and imaginary parts) is approximated as a collection of n linear segments, represented by the weighted sum of n semi-infinite linear functions. Using the numerical method, optimum weight vectors that maximize transducer power gain are obtained to model the real and imaginary parts of the source impedance curve. We get the values of optimum weight vectors and the rational input impedance function for the matching network, which are then synthesized in the desired topology by a continued partial fraction. Experimentally, we validate the novelty of the proposed method by designing matching networks of a wideband custom monolithic microwave integrated circuit (MMIC) low noise amplifier (LNA) in 1.3–2.3 GHz frequency band. The measured results of the designed LNA are significantly close to the simulated results. We bias our LNA at (5 V, 150 mA) and achieve a maximum noise figure of 1.25 dB, OP1dB of 26 dBm, and an average TOI of 38 dBm. Moreover, our design of custom LNA MMIC has an integrated ESD structure while occupying only 0.32 mm2 of chip area.

Electromagnetic (EM) simulators have already become established in the design of a variety of electromagnetic devices, such as MMICs (monolithic microwave integrated circuits), antennas, shields, electromechanical machines, and magnetic circuits. Such broad applicability results from the fact that the EM simulators are software packages for numerically solving the Maxwell’s fundamental electromagnetic field equations; for the same reason, and unlike some of the other simulators, they are independent of technology, models, foundry, and other such ephemeral considerations. Although designers have long carried out electromagnetic analysis of RF components and packages where necessary, the availability of commercial EM simulators1’2 since 1989 has made this task much more common, rapid, and easier. This development parallels the concurrent development of multi-chip module (MCM) technology for high-speed digital systems, as well as the front-ends of radio-frequency (RF) systems, such as receivers, transponders, transceivers, synthesizers, and transmit-receive modules. MCMs are a modern method of electronic packaging and integration that has the advantages of low-cost, compact size, and reliability. At low speeds/frequencies, the analysis, design, simulation, layout, and verification, of MCMs requires a number of software tools for computer-aided design (CAD), including process simulators, device simulators, circuit simulators, thermal simulators, and system simulators. For high-speed and RF MCMs, the design requirements make an additional CAD tool, namely EM simulator, indispensable.