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Graphene transistors using large area chemical-vapor-deposited (CVD) monolayer graphene and advanced dielectric stacks are constructed and examined. Top-gated devices with a SiO₂/Al₂O₃ gate-dielectric have a Dirac Point (DP) located at less than 5 V and asymmetric electron/hole mobility. In contrast, devices based on an advanced AlN interfacial layer have a DP located near 0V and a near symmetric carrier mobility- characteristics that could be more suitable for applications that require ambipolar behavior and low-power operation. For the first time, a measured RF cut-off frequency range of 1GHz is measured for top-gated transistors using CVD graphene. The results are of importance for the realization of graphene based, wafer-scale, high frequency electronics.

This paper presents a novel low-voltage single stage CMOS RF Variable Gain Amplifier (RFVGA) designed in 130 nm IBM CMOS process technology using current feed-back gain-independent impedance matching. The proposed RFVGA has a nearly constant gain over the 400 MHz–1 GHz frequency band. Also, it has a 70 dB gain variation (-40 dB to 30 dB) which is decibel-linear within this frequency band for a control voltage in the range of 0.41 V–0.81 V. The RFVGA demonstrates high linearity (THD ≈ -60 dB) and noise immunity (average Noise Figure ≤ 6 dB). It has an input referred third-order intercept point (IIP3) of -1.5 dBm, and an input reflection coefficient (S11) under -8 dB within the frequency band of interest. Also, it dissipates around 5 mW using a 1.2 V power supply. Further, Monte Carlo simulations incorporating process, supply voltage and temperature variations (PVT variations) as well as mismatch between devices (based on width and length of devices) indicate that the design is quite robust. The proposed RFVGA is highly suitable for mobile digital television (DTV) tuner applications.

Part I of this article provides a status update on the ongoing projects for both high-beta and low-beta applications. Some of these projects are already under production, others are perfecting prototypes and future plans. We first cover the funded projects and continue with the planned projects. The update naturally captures the state-of-the-art for superconducting RF (SRF) performance for applications in progress. Part II goes on to present a vision for future prospects for performance progress in the field, along with some advice about the likely fruitful R&D paths to follow. In general, the R&D paths chosen for discussion will benefit most SRF-based accelerators.

Part I of this article provides a status update on the ongoing projects for both high-beta and low-beta applications. Some of these projects are already under production, others are perfecting prototypes and future plans. We first cover the funded projects and continue with the planned projects. The update naturally captures the state-of-the-art for superconducting RF (SRF) performance for applications in progress. Part II goes on to present a vision for future prospects for performance progress in the field, along with some advice about the likely fruitful R&D paths to follow. In general, the R&D paths chosen for discussion will benefit most SRF-based accelerators.