This paper describes the design methodology and the On-Wafer (OW) measurement results of three Q-band four-stage MMIC High Power Amplifiers (HPA-LB, HPA-MB & HPA-HB) operating respectively in the 35-41GHz, 37-42GHz and 38-43GHz bandwidths. A Single-Ended HPA topology is considered (SE-HPA). These demonstrators are fabricated in 150-nm HEMT Gallium Nitride on Silicon Carbide technology (AlGaN/GaN on 70μm SiC substrate) for space applications, and thus considering space de-ratings. The main aim of this realization was the achievement of high output power associated with a high Power Added Efficiency. To obtain a good compromise between output power and PAE, a multi harmonic tuning approach of load and source impedances has been applied.The On-Wafer measured power results under pulsed wave signal of all SE-HPAs demonstrate a maximum output power (POUT) higher than 8W (39dBm) with 25% Power Added Efficiency (PAE) and more than 28dB of insertion gain (GI) in the overall frequency band of the interest.

This paper describes the design and characterization of a compact robust two-stage MMIC GaN Power Limiter using Cold FETs and Schottky Diodes. The limiter design is based on 0.15-µm GaN technology and can handle up to 450 W pulsed input power over the 2.6-3.6 GHz frequency band associated to a recovery time lower than 200 ns and a very low small signal insertion loss of 0.6 dB. To the authors knowledge, this is the highest power handling capability ever achieved on MMIC GaN based limiters.

This paper describes the design methodology and characterization of a 10W K Band packaged amplifier for space applications. The MMIC was developed on the new UMS 0.15 μm gate length GaN technology on SiC substrate as the final stage of a downlink satellite transmitter in the 17.3-20.2 GHz frequency band. A dedicated hermetic package has been developed around the MMIC with an output waveguide transition (compatible of WR51) for low loss integration in a Solid State Power Amplifier (SSPA) output combiner. This packaged High Power Amplifier (HPA) measured in CW mode, reaches 10W output power in saturation, with an associated 35% of Power Added Efficiency (PAE) and 10° AM-PM variation. These data are provided for a package backside temperature of 90°C.

The performances and the results of the qualification plan of the new high power GaN HEMT process GH25-10 are summarized in this paper. This technology would be the first ¼ gate length process qualified in Europe on 4” SiC substrate and will be fully open in foundry mode mid of 2014. It addresses applications up to 20 GHz with state of the art figure of merits in term of power density, gain, efficiency and reliability. The first part is dedicated to the description of the process and the associated spread data analysis. A second part is focused on the review of the performances, the electrical domain of validity (operating ratings) and modeling capabilities. This view is completed by some results of the qualification process. Finally, the last part will be focused on the product development based on the GH25-10 GaN technology.

This paper presents the successful development of a reproducible broadband Surface Mount Device (SMD) chip scale plastic packaging (CSP) platform based on hot-via technique for millimeter-wave MMICs encapsulation. Low loss package interconnect is demonstrated up to W-band. Significantly, with PCB-to-BGA-to-hot-via RF transitions, packaged E-band amplifier MMICs soldered onto evaluation boards demonstrated 20-dB range gain in the ETSI E-band of 71–86 GHz, in good agreement with initial simulations. To the author’s knowledge, this work represents the highest frequency demonstration of any SMT plastic package MMICs in CSP form factor, with remarkable measured performance in the millimetre-wave range.

This work presents a 13 W Ka-band GaN High Power Amplifier (HPA) operating in the 27-31.5 GHz bandwidth. This MMIC is developed using the qualified UMS 0.15 μm gate length GaN on 70 μm SiC substrate technology. Measurements in test fixture were performed over temperature in order to assess performance under Continuous Wave (CW) signal. At ambient chip backside temperature (Tb=25 °C), the HPA exhibits a small signal gain of 35 dB with a maximum Pout of 41.8 dBm, and a peak PAE of 32.5 % at 10 dBc for the quiescent bias point of VDQ=25 V and IDQ=60 mA/mm. For VDQ=22 V, this PAE increase up to 36 % with a 0.6 dB reduction of Pout. The HPA has a small chip size of 2.8 x 2.6 mm² with only three biasing pads on each chip side. This HPA achieves among the best performances in terms of trade-off between Pout, gain, PAE and chip size.

This paper describes the main characteristics of the new GaN-on-SiC technology in development at UMS. This technology is based on a 0.15-μm gate-length and it is in the phase of industrial qualification for a target release by the end of the year. The results of two out of four demonstrators already successfully designed on the new technology are also reported: a 29.5-36 Ghz 9W HPA and a 15.5-18.5 GHz 20W HPA.

This paper describes the performances of a new power 0.5 μm gate length AlGaN / GaN HEMT process named GH50_10. This process has been developed to address applications and market needs up to 7 GHz. A specific emphasis has been attached to find a trade- off in between power / efficiency and linearity. After an introduction of the context, a short description of the process manufacturing is given including spread of the DC parameters. From the qualification procedure, key reliability figures of the process are presented like the main energy of activation and an evaluation of the Median Time to Failure, evaluated respectively to 1.95ev and 10⁶ hours at 200°C. Power performances are presented from L to C bands from 15W for the elementary power transistors to 50W for high power packaged transistors. This technology is presently available at industrial level to address products requirements for telecom and military needs. Compliance to space requirement is underway.

Applications in the range of E to W bands are emerging during the last years specially in the field of Radio and security for active scanning systems. It required both low noise receiver and medium power amplifier which needs to use high performances, reliable millimeter wave technology. This paper describes basic fundamental of a 0.1 μm gate length process in term of process, characteristics and modelling. A specific emphasis is attached to the modelling issue in this domain of frequency and the difficulty to get reliable analysis. It is stressed at the end that thanks to accurate modelling in the low frequency part (Ka to Q bands), it allows to predict the behaviour of the device in E band. This methodology has been successfully applied to the design of a wideband LNA and HPA.

We report on the design and fabrication of high-efficiency monolithic X-band power amplifiers using a well optimized GaInP/GaAs heterojunction bipolar transistor (HBT) technology. Ballast resistors have been introduced to each emitter finger to avoid completely the current collapse effect and thus enabling long pulse and continuous wave (CW) operation. The amplifiers are designed for operation at moderate current densities to reduce junction temperature and to improve reliability. State-of-the-art performances with maximum output powers of 9 W with a power-added efficiency (PAE) of 42 % and peak power-added efficiencies of 45 % have been achieved at 10 GHz under critical long pulse conditions (pulse width=100 /spl mu/s, duty cycle=10 %). To our knowledge these results represent the best performance of any GaInP/GaAs HBT MMIC power amplifier considering efficiency, output power, operation frequency, and pulse conditions.

GaInP/GaAs HBT technology is an excellent alternative to GaAlAs/GaAs HBTs. We present new X-Band power results both on discrete devices and on MMICs obtained using this new type of HBT. 12-2×30-μm² finger discrete devices show an output power of 1W at 10 GHz with a power added efficiency of 43% under near class A bias conditions. The dependence of the power gain on the HBT topology has been simulated and that predicts precisely the device performances. First power amplifier MMICs have been produced by Thomson-CSF. Those MMIC amplifiers achieve an output power above 1 W at 10 GHz under both CW and pulsed conditions. The power gain is higher than 12dB at 10 GHz. At the same RF frequency, the power added efficiency reaches 35% and 25% under pulsed conditions (3 μs, 10% duty cycle) and CW respectively. These first results are promising, and improved results are expected soon by tuning the output matching network and using higher gain devices.