Embedded IC and high-Q passives technology for ultra-compact Ku-band VCO module

In this letter, we present a novel ultra-compact embedded IC integration approach for system-on-package (SOP) based solutions for RF and wireless communication applications. This concept is applied to the integration of a Ku band VCO module. The module fabrication is described and the impact of the packaging on the chip-set performances is discussed. The final thickness of the module is about 150 /spl mu/m. The embedded VCO exhibits an oscillation frequency of 15.4 GHz, a phase noise of -99.2 dBc/Hz at a 1 MHz offset and maximum output power of 10.67 dBm. Multilayer interconnects built with modified MCM-D technology using advanced photosensitive epoxy Intervia 8000 is described. Characterization and modeling of RF inductors are detailed and show quality factor as high as 80 at 10 GHz.     

Reconfigurable RFICs in Si-based technologies for a compact intelligent RF front-end

This paper presents reconfigurable RF integrated circuits (ICs) for a compact implementation of an intelligent RF front-end for multiband and multistandard applications. Reconfigurability has been addressed at each level starting from the basic elements to the RF blocks and the overall front-end architecture. An active resistor tunable from 400 to 1600 /spl Omega/ up to 10 GHz has been designed and an equivalent model has been extracted. A fully tunable active inductor using a tunable feedback resistor has been proposed that provides inductances between 0.1-15 nH with Q>50 in the C-band. To demonstrate reconfigurability at the block level, voltage-controlled oscillators with very wide tuning ranges have been implemented in the C-band using the proposed active inductor, as well as using a switched-spiral resonator with capacitive tuning. The ICs have been implemented using 0.18-/spl mu/m Si-CMOS and 0.18-/spl mu/m SiGe-BiCMOS technologies.     

Development of GaN wide bandgap technology for microwave powerapplications

A complete investigation of GaN-based wide-bandgap electronic devices and circuits has been presented. It includes an understanding of the device technology (e.g. characterization systems, testing, and modeling), of the devices' reliability (e.g. fabrication, thermal analysis), and the development of circuits and system applications, including radar and digital communication systems     

Thermal analysis of AlGaN-GaN power HFETs

In this paper, we present a thermal analysis of AlGaN-GaN power heterojunction field-effect transistors (HFETs). We report the dc, small-signal, large-signal, and noise performances of AlGaN-GaN HFETs at high temperatures. The temperature coefficients measured for GaN HFETs are lower than that of GaAs pseudomorphic high electron-mobility transistors, confirming the potential of GaN for high-temperature applications. In addition, the impact of thermal effects on the device dc, small-signal, and large-signal characteristics is quantified using a set of pulsed and continuous wave measurement setups. Finally, a thermal model of a GaN field-effect transistor is implemented to determine design rules to optimize the heat flow and overcome self-heating. Arguments from a device, circuit, and packaging perspective are presented.     

Impact of downscaling and poly-gate depletion on the RF noise parameters of advanced nMOS transistors

For the first time, the effects of poly depletion on the RF noise performance of advanced CMOS transistors are reported and analyzed. Based on measurements and physical device simulations we quantify the increasing danger of poly gate depletion with downscaling on the RF noise parameters of CMOS devices. While poly depletion does not affect the minimum noise figure, it results in a degradation of the noise matching freedom for RFIC designers. This trend worsens with technology downscaling.     

High-frequency noise in AlGaN/GaN HFETs

We present in this letter the benefits of GaN-based electronic devices for low-noise MMICs. A temperature-dependent two-temperature noise model for AlGaN/GaN HFETs is implemented on a wide range of bias conditions. This study enables to access the device high-frequency noise parameters, and allow a comparison of the noise performances with SiC and GaAs technologies.     

The Role of Volume Inversion on the Intrinsic RF Performance of Double-Gate FinFETs

Quantum interactions between the inversion channels of multigate devices and their resulting effects on charge distribution and carrier mobility are analyzed in this paper. Results of this analysis are then used to assess the role of volume inversion on the intrinsic RF performance of double-gate FinFETs. Thin-fin devices are beneficial to low-operating and high-performance powers, and wideband RF blocks, while they are detrimental to low-power cross coupled pair-based RF oscillators, and are more power hungry for high-performance oscillators. Also, we highlight that the intrinsic capacitance variation induced by the fin volume inversion dominates the power and wideband RF performance of FinFETs over the variation in carrier mobility. Accurate definition of fin below 8-10 nm will enable extreme RF performance devices     

Improved RF modeling techniques for enhanced AlGaN/GaN HFETs

Modeling procedures of an AlGaN/GaN HFET that incorporate the effects of both a GaN cap layer and an AlN sub-buffer layer are presented. A single off-state measurement method to extract all eight parasitic elements of an enhanced HFET has been successfully applied. In addition, procedures to model the nonlinear drain-to-source current characteristics featuring a kink are described.