Design of a 77-GHz LC-VCO With a Slow-Wave Coplanar Stripline-Based Inductor

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Prediction of RF performances of advanced MOS transistor from dc and low frequency measurements

This work presents a new method to easily and rapidly extract RF figures of merit of MOSFET transistors. Using DC and low frequency measurements, the extrinsic resistances (Rg, Rs, Rd), the intrinsic conductances (gm, gd), and the input capacitance Cgg have been extracted. The evaluation of these parameters has enabled to compute 2 RF figures of merit (FoM), namely, the current gain cutoff frequency fT and the maximum oscillation frequency fmax. It has been shown that both the proposed method and the conventional RF extraction technique give quite close values

Low‐loss broadband (DC to 220 GHz) S‐CPW to S‐CPS transition for S‐CPS coplanar probing

International audienceThe practical issue of probing coplanar stripline (CPS) structures is addressed in this Letter. A compact slow-wave coplanar waveguide (S-CPW) to slow-wave CPS (S-CPS) transition was designed and fabricated in a 55 nm BiCMOS process of STMicroelectronics. The signal strips of the slow-wave CPW and slow-wave CPS have been directly connected while the ground strips have been tied together through combination of transmission lines laid out on the top metal layer of the back-end-of-line of the technology. Thanks to its flexibility, the proposed transition can be resized to match with a wide range of slow-wave CPS slot. Tested from DC to 220 GHz, the back-to-back transition structure showed insertion loss lower than 1.4 dB and return loss better than 15 dB, respectively. To the best of author's knowledge, it is the first integrated slow-wave CPW/CPS transition introduced within the mentioned mm-wave band

3-[2-(2-Amino-1H-benzo[d]imidazol-1-yl)ethyl]-1,3-oxazolidin-2-one

In the title compound, C12H14N4O2, the benzimidazole ring is almost planar (r.m.s. deviation = 0.03 Å), with the fused ring system slightly folded at the shared atoms, with a dihedral angle of 3.4 (1)°. The oxazolidinone ring displays a twisted conformation on the –CH2–CH2– bond and its mean plane makes a dihedral angle of 57.4 (1)° with the benzimidazole ring mean plane. In the crystal, molecules are linked by N—H...O and N—H...N hydrogen bonds, forming chains propagating along the a-axis direction. The chains are linked by C—H...O and C—H...N hydrogen bonds, forming a three-dimensional structure, which is reinforced by C—H...π interactions

Design of coupled slow-wave CPW millimeter-wave bandpass filter beyond 100 GHz in 55-nm BiCMOS technology

International audienceThe design and experimental results of millimeter-wave bandpass filters (BPFs) implemented in 55-nm BiCMOS technology and operating around 120 GHz are presented in this article. Slightly modified coupled line filters' structures are used in the designs. It allows generating the transmission zero at the upper stopband, leading to the selectivity of enhanced filters. The coupled line structure is implemented in two technologies, microstrip coupled lines and coupled slow-wave (SW) coplanar waveguides (CS-CPWs). The latter shows more design flexibility, allowing to reach a better filtering performance than the microstrip filters, i.e., better in-band flatness and higher selectivity. Good agreement is achieved between simulation, modeling, and measurement results. Also, the overall length of the filter based on CS-CPWs is smaller as compared to the filters based on the microstrip lines, thanks to the SW propagation

Innovative millimetre‐wave resonators based on slow‐wave coplanar stripline components

International audienceIn this paper, the slow-wave coplanar stripline (S-CPS) technology is utilised to design high performance and small footprint resonators operating within the millimetre-wave band from 50 to 80 GHz. The proposed resonators are designed based on high quality factor quasi-lumped capacitances and inductances offering a great flexibility in terms of design. The derivation of these components from the S-CPS is explained theoretically and their behaviour is validated by EM simulation; an equivalent electrical model is also developed. The proposed concepts are demonstrated in the BiCMOS 55-nm technology, and a good agreement between modelling, EM simulation and measurement results is achieved. The proposed devices could later be considered as interesting elementary blocks for the design of mm-wave filters

mm-Wave Through-Load Switch for in-situ Vector Network Analyzer on a 55-nm BiCMOS Technology

International audienceIn this paper, an innovative millimeter-wave (mm-wave) through-load switch for in-situ reflectometers and on-wafer calibration is proposed. This two-port device can switch between two states: (i) a through connection or (ii) a 50 Ω load for both of its ports. The through-load switch is composed of a 3-dB directional coupler and two nMOS transistors controlled through a biasing voltage applied to their gate. Measurement results of a 120-GHz 3-dB directional coupler are provided up to 145 GHz together with EM simulations and circuit-level simulations up to 220 GHz of the through-load switch. A wide bandwidth is obtained, from 73 GHz to 179 GHz, with limited insertion loss of 2 dB

Miniaturization of Transmission Lines: Meandered Slow-wave CPWs

International audienceThis work presents novel transmission line structures based on Meandered Slow-wave CoPlanar Waveguides (MS-CPWs), aiming to achieve high miniaturization. As a proof-of-concept, these two kinds of transmission lines were designed and fabricated in the AMS 0.35 mu m CMOS technology together with classical straight and meandered microstrip lines. Measurement results from 70 kHz to 100 GHz of the fabricated transmission lines are presented. At 80 GHz, all the considered transmission lines present similar quality factors, ranging between 10 and 14. On the other hand, at this frequency, one of the developed MS-CPW presents an effective dielectric constant of 88, while the meandered microstrip exhibits an equivalent effective dielectric constant of 51, thus leading to higher compactness for the MS-CPW