GaN-based transistors using buffer-free heterostructures for next generation RF devices

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C-doped AlN/GaN HEMTs for High efficiency mmW applications

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Novel heterostructures for millimeter-wave GaN devices

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Low RF losses up to 110 GHz in GaN-on-silicon HEMTs

International audienceWe report on low RF losses at the interface between the epitaxial structure and the silicon substrate (less than 0.8 dB/mm up to 110GHz) of AlN/GaN high electron mobility transistors (HEMTs) grown on silicon substrate. This stateof-the-art performance makes GaN-on-Silicon HEMTs competitive with GaN-on-SiC in terms of parasitic RF losses. Furthermore, a maximum dc output current close to 1 A/mm together with low leakage current of 1 μA/mm and low trapping effects are achieved while using a short gate length of 0.2 μm. The large signal measurements confirmed the high quality of the epitaxy and the device processing as well as the low parasitic RF losses. This is reflected by a high output power density of 4.5 W/mm achieved at 18 GHz

First demonstration of RF GaN-based transistors using buffer-free heterostructures with low trapping effects

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Multi-Level Modeling of Wireless Embedded Systems

The design of wireless embedded systems needs their efficient and realistic simulation to verify that requirements are met. The reproduction of communication behavior is crucial to assess the performance of hardware and software components, e.g., dependability and energy consumption. This work presents and discusses different levels of abstraction for the simulation of the communication behavior. Each level addresses different aspects of the communication and allows to specify different kinds of detail; furthermore, it requires a specific modeling approach. Their use and the corresponding computational overhead is shown in the specific case of the Bluetooth standard. We also show that simulation results obtained at a low abstraction level can be used at a higher one to drive design choices