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A Broadband 200 GHz Amplifier with 17 dB Gain and 18 mW DC-Power Consumption in 0.13

This letter presents a 200 GHz amplifier for low-power high data-rate wireless communications. With large bandwidth and energy efficiency as concurrent goals, cascode stages for high power gain and dual-band matching networks to maximize the bandwidth have been employed. The resulting amplifier has been implemented in a 450 GHz SiGe BiCMOS technology, requiring a circuit area of only 800 μm × 300 μm. The characterized circuit exhibits 16.9 dB of maximum power gain, 44 GHz of bandwidth and -3.5 dBm of output power at 1 dB compression, while requiring only 18 mW of DC-power.

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This letter presents a compact model for flexible analog/RF circuits design with amorphous indium-gallium-zinc oxide thin-film transistors (TFTs). The model is based on the MOSFET LEVEL=3 SPICE model template, where parameters are fitted to measurements for both dc and ac characteristics. The proposed TFT compact model shows good scalability of the drain current for device channel lengths ranging from 50 to 3.6 μm. The compact model is validated by comparing measurements and simulations of various TFT amplifier circuits. These include a two-stage cascode amplifier showing 10 dB of voltage gain and 2.9 MHz of bandwidth.

m SiGe BiCMOS

Fully printed organic field effect transistors (OFETs) are fabricated on a flexible, 100-μm-thick, polyethylene terephthalate substrate using high-throughput printing techniques: 1) Cyflex; 2) gravure; 3) screen; and 4) flexographic printing without using a cleanroom, and below 130°C. The dependence of the transconductance g_m, transit-frequency f_T, and intrinsic-gain on the bias drain current I_D are measured. The OFETs show intrinsic gain for I_D >10 nA mm (per millimeter width), and reach f_T=64 kHz at I_D = 16 μA/mm, whereas the g_m loss with frequency is 10% up to f_T. Unlike silicon MOSFETs, the dependence of the OFET g_m on the f_T in the subthreshold region is found to be weaker than I_D^1.0. In addition, the overlap capacitance of the staggered-geometry OFET shows strong frequency dependence, and this is shown to be related to the overlap semiconductor. For the first time, it is found that the impact of process variations and bias stress on the OFET analog characteristics can be significantly attenuated by biasing the device at a fixed I_D. This approach is tested on an array of five amplifiers, reaching the gain-bandwidth product of 32 kHz, within ±3.7% variations.

A Compact a-IGZO TFT Model Based on MOSFET SPICE

This paper presents a travelling-wave amplifier (TWA) for wideband applications implemented in a 0.13 µm SiGe BiCMOS technology (ft = 300 GHz, fmax = 500 GHz). The gain cell employed in the TWA is designed to compensate the transmission-line- losses at high frequencies in order to extend the bandwidth as well as the gain bandwidth product (GBP). A gain of 10 dB and a 3-dB bandwidth of 170 GHz are measured for the fabricated TWA. The chip has a chip area of 0.38 mm² and a power consumption of 108 mW. Compared against the state of the art, the presented design achieves the highest reported GBP per area and power consumption.

{\rm Level}=3

In this paper, the opportunities, limits and challenges for future silicon-based field effect transistors (FETs) tailored for radio frequency (RF) and millimeter (mm)-wave circuit design are discussed. After the review of CMOS FET scaling down to the 10 nm node, advanced CMOS techniques such as silicon on insulator (SOI), strained silicon, high-k, low temperature and multigate transistors are treated. Moreover, emerging Beyond CMOS FET concepts based on silicon nanowires, graphene and carbon nano tubes (CNTs) are discussed as potential replacement or extension to CMOS.

Template for Analog/RF Circuit Designs

This letter presents an active 200 GHz fundamental down-conversion mixer based on the Micromixer topology for low-power high data-rate wireless communications. The mixer-core operation requires a -5 dBm LO-signal, which is generated on-chip from an external single-ended source of only -20 dBm by means of a power-efficient LO-driver and a passive balun. Mixer, LO-driver and balun have been implemented together in a 450 GHz SiGe BiCMOS technology occupying a circuit core area of 0.21 mm2. For a 200 GHz LO-signal, the characterized circuit exhibits a maximum conversion gain of 5.5 dB over a 3 dB RF-bandwidth of 30 GHz, requiring only 17.4 and 22.5 mW of DC-power in the mixer core and in the LO-driver, respectively.

Analog Characteristics of Fully Printed Flexible Organic Transistors Fabricated With Low-Cost Mass-Printing Techniques

Depletion-mode CNTFETs are being fabricated successfully with useable tolerances and compact models are now available for circuit design and engineering. This paper presents the first design study of mixers based on those devices. The impact of peculiar device features and parasitic on analog and RF circuits is discussed in detail and the cascode mixer is selected to overcome challenges specific to the available technology. Circuit performance and design for operation in the 2.4 GHz IMS band are described in detail: while consuming 182 mW and driven with −2 dBm LO power, the mixer provides 8 dB conversion gain to a 10 MHz IF frequency.

170 GHz SiGe-BiCMOS Loss-Compensated Distributed Amplifier

This paper presents a cascode amplifier for bendable analog and radio-frequency electronic systems in a flexible amorphous indium gallium zinc oxide (a-IGZO) TFT technology, featuring a minimum gate length of 5 μm. The design is optimized for large bandwidth. The circuit design was carried out with a MOSFET LEVEL=3 SPICE model template. The required model parameters were extracted from both DC and AC measured characteristics. Measurements results show 10.5 dB of voltage gain and a 3 dB bandwidth of 2.62 MHz; the small-signal performance was closely predicted by simulations. The presented circuit provides the highest frequency of operation reported for a single-stage cascode amplifier in a-IGZO TFT technology to date.

Review of advanced and Beyond CMOS FET technologies for radio frequency circuit design

This letter presents the design, implementation, and measurements of two monolithic low-IF receivers compliant with the main WLAN standards. The first receiver targets the three 5GHz U-NII bands, while the second allows dual-band operation in the 2GHz and 5GHz bands. Fabricated in a 47GHz-f/sub t/ BiCMOS technology, both consist of a low-noise preamplifier, two matched active singly-balanced mixers and two polyphase filters, used to generate quadrature LO signals and provide image-rejection. The single-band receiver exhibits 25 dB of conversion gain, 8.9 dB of NF and -19 dBm of P/sub 1 dB/, while consuming 19 mW. The dual-band receiver shows similar performances in the 5GHz band, and extends its operation in the 2GHz band, achieving 33.4dB of conversion gain, 4.1dB of NF and -26dBm of P/sub 1 dB/, while consuming 14.9mW.

A Low-Power Broadband 200 GHz Down-Conversion Mixer with Integrated LO-Driver in 0.13

This paper presents two Cherry-Hooper amplifiers for bendable analog radio-frequency electronic systems fabricated in flexible self-aligned amorphous indium gallium zinc oxide (a-IGZO) thin-film-transistor (TFT) technology. The first circuit is a wideband single-stage Cherry-Hooper amplifier providing a voltage gain of 10.4 dB over a 3 dB bandwidth of 3.5 MHz and a gain-bandwidth product (GBP) of 11.6 MHz. For the second circuit, a two-stage Cherry-Hooper amplifier, a voltage gain of 33.3 dB with a 3 dB bandwidth of 400 kHz and a GBP of 18.5 MHz were measured. The simulations, which are based on a Rensselaer Polytechnic Institute-amorphous TFT (RPI-aTFT) model, are in good agreement with measurements.