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In this article, the electrical model of a millimeter-wave (mmW), silicon-based noise source is developed in the frequency range up to 325 GHz. The model is studied as a function of the biasing current and the structure size. The noise source is based on a Schottky diode realized on the 55-nm SiGe BiCMOS technology from STMicroelectronics, Crolles, France. Due to the ability of being integrated on silicon, this noise source can be used for high-frequency in situ noise characterization of advanced silicon CMOS or bipolar technologies in the mmW range. In previous study, the diode was used as a noise source when biased near the avalanche regime, and an excess noise ratio (ENR) up to 20 dB has been achieved in a frequency range up to 260 GHz. In this article, the ENR value of the diode is retrieved from the electrical model and compared to the value extracted by measurements. The extracted ENR value was also studied for several diode sizes and biasing currents and measured up to 325 GHz, with a good agreement with the modeling. [ABSTRACT FROM AUTHOR]

The system and transistor-level design of low-power millimeter wave (mm-wave) active tags in silicon is discussed in detail. Two active mm-wave tags with identical system architecture, padframe, and chip size were designed and fabricated in 55-nm SiGe BiCMOS and 45-nm SOI CMOS technologies, respectively. They feature a three-stage low-noise amplifier (LNA), a wake-up detector, a BPSK modulator, and two variable gain output stages, each driving a separate transmit antenna in antiphase. The wake-up detector can be used to switch OFF all the blocks except for the LNA and detector, thus further reducing power consumption. The measured performance of the SiGe and SOI chips is remarkably similar: 19- and 20-dB gain, 9- and 8-dB noise figure, and 25-/10.8-mW (active/idle) and 18-mW power consumption, respectively. The SiGe tag was flip-chip-mounted on a mini-PCB with one receive and two transmit antennas for system level functionality tests carried out over a distance of 5 m. The SiGe-tag wake-up sensitivity was verified to be −62 dBm, in excellent agreement with simulation results. [ABSTRACT FROM PUBLISHER]

Power amplifier (PA) design for 160-GHz applications in an advanced SiGe heterojunction bipolar transistor (HBT) technology with saturated output power (Psat) in excess of 10 dBm is presented. The architecture is based on a three-stage pseudodifferential configuration that was implemented in SiGe HBT evaluation technology with f\max of 400 GHz. At saturation, a PA breakout circuit delivers 10 dBm with 20-dB gain. From 150 to 170 GHz, the small-signal gain is within 20–32 dB and the output referred 1-dB compression point (P1\ dB) is 8.5 dBm at 160 GHz. High output power was possible due to optimum device sizing, efficient layout, and accurate EM modeling. To our best knowledge, this is the highest output power reported for silicon PAs operating beyond 120 GHz. [ABSTRACT FROM AUTHOR]

This paper describes a methodology for extracting and verifying the high-frequency model parameters of the HICUM L0 and L2 models of a silicon–germanium HBT from device and circuit measurements in the 110–325-GHz range. For the first time, the non-quasi-static effects, missing in the HICUM/L0 model, are found to be essential in accurately capturing the frequency dependence of the transistor maximum available power gain beyond the inflection frequency for unconditional stability. Furthermore, it is demonstrated that the optimal partitioning of the area and periphery components of the junction base–emitter, base–collector, and collector–substrate capacitances, and of the internal and external base and collector resistances can only be determined from S-parameter measurements beyond 200 GHz. The extracted models are validated on state-of-the-art linear and nonlinear circuits (amplifier, voltage-controlled oscillator (VCO), and VCO + divider chain) operating at frequencies as high as 240 GHz. [ABSTRACT FROM AUTHOR]

A D-band SiGe HBT total power radiometer is reported with a peak responsivity of 28 MV/W, a noise equivalent power (NEP) of 14–18 \fW/Hz^1/2, and a temperature resolution better than 0.35 K for an integration time of 3.125 ms. The 1/f noise corner of the radiometer is lower than 200 Hz. Fabricated in a developmental technology with 270-GHz fT and 330-GHz fMAX, it includes a five-stage low-noise amplifier (LNA) with 4–7-GHz bandwidth and over 35 dB of gain centered at 165 GHz, along with a square-law detector with an NEP below 6 \pW/Hz^1/2 up to 170 GHz. An average system noise temperature of 1645 K is obtained using the Y-factor method and a noise bandwidth of 10 GHz calculated from the measured S21(f) characteristics of the radiometer. The reduced 1/f noise corner frequency in the presence of the amplifier, compared to that of the detector, appears to indicate that, unlike in III–V radiometers, LNA gain fluctuations are not a problem in SiGe HBT radiometers. The circuit consumes 95 mW and occupies \ 765\,\times\ 490∼\mu\ m^2. Wafer mapping of the radiometer sensitivity and of the amplifier gain was performed across different process splits. The mapping results demonstrate that the radiometer can be employed as a relatively simple and area-efficient transistor noise-measure monitor, useful in SiGe HBT vertical profile optimization. [ABSTRACT FROM AUTHOR]

Noise parameter (F\min, Zopt, and R n) measurements of SiGe HBTs are provided for the first time in the 70–170-GHz range. In the W-band, this is accomplished by integrating on a single chip a source impedance tuner with the device-under-test and a low-noise amplifier with 3.8-dB noise figure. Noise-figure measurements were performed over multiple source impedances using a commercial single-sideband downconverter. In the D-band, where off-chip setup losses are overwhelming, the source impedance tuner, the transistor under test, and the entire receiver with a noise figure of 10 dB were integrated on a single silicon die, and direct noise-figure measurements were conducted first on the test setup with the transistor under test, and next on the reference receiver without the test transistor. Both analog and digital source impedance tuners, based on n-MOSFET variable resistors, n-MOSFET switches, and accumulation-mode varactors, have been designed and characterized. Finally, the existing technique to extract the SiGe HBT noise parameters from Y-parameter measurements, without any noise-figure measurements, is refined to include noise correlation and is validated up to 170 GHz. The measured source–pull and Y-parameters results show that the minimum noise figure of state-of-the-art SiGe HBTs remains below 5 dB throughout the D-band. [ABSTRACT FROM AUTHOR]

This paper presents a complete 2.5-V 77-GHz chipset for Doppler radar and imaging applications fabricated in SiGe HBT and SiGe BiCMOS technologies. The chipset includes a 123-mW single-chip receiver with 24-dB gain and an 1P1 dB of -21.7 dBm at 76-GHz local oscillator (LO) and 77-GHz RF, 4.8-dB double-sideband noise figure at 76-GHz LO and 1-GHz IF, and worst case -98.5 dBc/Hz phase noise at 1-MHz offset over the entire voltage-controlled oscillator tuning range at room temperature. Monolithic spiral inductors and transformers result in a receiver core area of 450 μm × 280 μm. For integration of an entire 77-GHz transceiver, a power amplifier with 19-dB gain, +14.5-dBm saturated output power, and 15.7% power-added efficiency is demonstrated. Frequency divider topologies for 2.5-V operation are investigated and measurement results show a 105-GHz static frequency divider consuming 75 mW, and a 107-GHz Miller divider consuming 33 mW. Measurements on all circuits confirm operation up to 100 °C. Low-power low-noise design techniques for each circuit block are discussed. [ABSTRACT FROM AUTHOR]