Benefits and validation of 4-dummies de-embedding method for characterization of SiGe HBT in G-band

International audienceBy taking into account the transistor parasitic lumped elements originated from the contact pads and the metal interconnections including the top-down connection, an enhanced de-embedding procedure for on-wafer G-band measurements has been developed and implemented. This method relies on a transistor access lumped element modelling, with a special care for the top-down connection, which prove to be the main contributor to the series parasitic effects. RF measurements on four test structures are sufficient to build the entire access model. The improved performance of such de-embedding technique is demonstrated, especially in the upper range of G-band, on the small-signal equivalent circuit extraction of advanced SiGe HBTs

Gate length dependent transport properties of in-plane core-shell nanowires with raised contacts

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Uncertainties assessment of noise parameters in D- band using in situ tuner techniques

International audienceWhen transistor noise characterization becomes a difficult task at millimeter wave range, the accuracy on the resulting noise parameters is not or poorly discussed. Within this context, this paper aims to present a methodology to estimate the uncertainties related to the extraction of the four noise parameters when using in situ tuner techniques, in the 130-170 GHz frequency range. B9MW SiGe HBT from STMicroelectonics was used as a test vehicle for the noise characterization and uncertainties assessment

Caractérisation et extraction du schéma équivalent petit signal en bande G de transistor bipolaire à hétérojonction SiGe:C de dernière génération et montrant des performances fT/fmax=300/400 GHz

National audienceLa validation jusqu’à 220 GHz du modèle petit signal de transistors bipolaires à hétérojonction Si/SiGe de la technologie B5T de STMicroelectronics de dernière génération est pour la première fois présentée. Ce modèle équivalent petit signal a été extrait jusqu’à 110 GHz et validé par des mesures hyperfréquences jusqu’à 220 GHz. Ce travail permet d’envisager la conception de circuits à ces fréquences, tels que des amplificateurs large bande dédiés au test in-situ

Miniaturized Microcantilever-based RF Microwave Probes Using MEMS Technologies

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Millimeter-wave in situ tuner : an efficient solution to extract the noise parameters of SiGe HBTs in the whole 130-170 GHz range

SiGe HBT noise parameters ( , and ) are for the first time extracted in the entire 130 - 170 GHz frequency range. This achievement is realized using a D-band on-chip source-pull system, which includes an impedance tuner integrated with the transistor under test. On-wafer noise power measurements on this system were performed for each tuner impedance state, from which are extracted the transistor noise parameters in the complete -band

Small-Signal Characterization and Modeling of 55 nm SiGe BiCMOS HBT up to 325 GHz

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A 135-150 GHz frequency quadrupler with 0.5 dBm peak output power in 55 nm SiGe BiCMOS technology

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Ionic Polarization Occurrence in BaSrTiO3 Thin Film by THz-Time Domain Spectroscopy

BaSrTiO3 thin films in a paraelectric phase were characterized on the one hand from 1 GHz to 200 GHz by microwave measurements on interdigitated capacitance and coplanar waveguides and on the other hand up to 3 THz by Time Domain Spectroscopy. An overlap of the polar nanoregion relaxation mechanism with a characteristic frequency around 800 GHz and of the ionic polarization with a relaxation frequency around 3 THz is directly evidenced experimentally

Dielectric dispersion of BaSrTiO3 thin film from centimeter to submillimeter wavelengths

The dielectric dispersion of ferroelectric BaxSr1-xTiO3 (BST) thin film in a paraelectric phase was characterized from centimeter to submillimeter wavelengths. To this aim, interdigitated capacitors were patterned on a micrometer scale onto a BST layer with a barium concentration of 0.5 and were subsequently integrated by using a coplanar waveguide technology. The retrieval of the complex permittivity of BST was performed by vectorial scattering parameter measurements up to 190 GHz for various controlling dc field up to 300 kV/cm. At higher frequency, submillimeter wavelength measurements were performed by time domain spectroscopy under free space condition. On this basis, the dispersion of the real part of the permittivity along with the loss tangent are retrieved in agreement with a distributed interaction of ac-field with soft phonons vibration modes, and overlapping between dipole polarization and ionic polarization is observed, around 700 GHz. It is also shown that dipole polarization can be attributed to the presence of small polar nanoregions in the BST film which act as in ferroelectric material with diffuse phase transition. (c) 2011 American Institute of Physics. [doi:10.1063/1.3531534