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International audience; This paper presents the full modeling and a methodology for de-embedding the interferometric scanning microwave microscopy measurements by means of dopant profile calibration. A Si calibration sample with different boron-doping level areas is used to that end. The analysis of the experimentally obtained S11 amplitudes based on the proposed model confirms the validity of the methodology. As a specific finding, changes in the tip radius between new and used tips have been clearly identified, leading to values for the effective tip radius in the range of 45 nm to 85 nm, respectively. Experimental results are also discussed in terms of the effective area concept, taking into consideration details related to the nature of tip-to-sample interaction.The authors wish to acknowledge the support from EC by means of “Marie Curie” fellowship in the framework of PEOPLE-2012-ITN project: Microwave Nanotechnology for Semiconductor and Life Science—NANOMICROWAVE, under GA: 317116, as well as the Region Nord-Pas-de-Calais for supporting this work under the project CPER CIA research and the National Research Agency (ANR) under the program Equipex (EXCELSIOR project).

Microwave reflectometry is proposed as an effective technique to detect the vibration of capacitively transduced microelectromechanical resonators. The transducer capacitor is probed by an incident wave, which is reflected being modulated by the time variations of the resonator displacement. Calculations demonstrate that the sensitivity of the technique is maximum for a given microwave frequency depending on the transducer total capacitance. Experimental data show that capacitance variations as low as 3 zF/√Hz are measurable at 4 GHz for the studied devices. Such a performance corresponds to a sub-picometer resolution in vibration amplitude of the microelectromechanical resonator. The measurement technique is particularly appropriate for resonant sensors when high signal-to-noise ratio and fully electrical detection are required. It can be used for device resonance frequency up to several hundreds of MHz.

A fully integrated electromechanical resonator is described that is based on high mobility piezoelectric semiconductors for actuation and detection of nanoscale motion. We employ the two-dimensional electron gas present at an AlGaN/GaN interface and the piezoelectric properties of this heterostructure to demonstrate a resonant high-electron-mobility transistor enabling the detection of strain variation. In this device, we take advantage of the polarization field divergence originated by mechanical flexural modes for generating piezoelectric doping. This enables a modulation of carrier density which results in a large current flow and thus constitutes a motion detector with intrinsic amplification.