Peter Song

On the Analysis and Design of Low-Loss Single-Pole Double-Throw W-Band Switches Utilizing Saturated SiGe HBTs

This paper describes the analysis and design of saturated silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) switches for millimeter-wave applications. A switch optimization procedure is developed based on detailed theoretical analysis and is then used to design multiple switch variants. The switches utilize IBMs 90-nm 9HP technology, which features SiGe HBTs with peak f T/ fmax of 300/350 GHz. Using a reverse-saturated configuration, a single-pole double-throw switch with a measured insertion loss of 1.05 dB and isolation of 22 dB is achieved at 94 GHz after de-embedding pad losses. The switch draws 5.2 mA from a 1.1-V supply, limiting power consumption to less than 6 mW. The switching speed is analyzed and the simulated turn-on and turn-off times are found to be less than 200 ps. A technique is also introduced to significantly increase the power-handling capabilities of saturated SiGe switches up to an input-referred 1-dB compression point of 22 dBm. Finally, the impact of RF stress on this novel configuration is investigated and initial measurements over a 48-h period show little performance degradation. These results demonstrate that SiGe-based switches may provide significant benefits to millimeter-wave systems.

A Low-Loss and High Isolation D-Band SPDT Switch Utilizing Deep-Saturated SiGe HBTs

A single-pole double-throw switch, utilizing double-shunt, deep-saturated HBTs is implemented in a 0.13 μm SiGe BiCMOS technology, occupying 0.36 mm2 of IC area. A superior switch performance is identified when HBTs are operated in saturation regime, and state of the art performance is achieved at D-band frequencies from 96 to 163 GHz. Measurements show a minimum insertion loss of 2.6 dB at 120 and 150 GHz, a highest isolation of 29 dB at 120 GHz and an input 1 dB compression point of 17 dBm at 94 GHz, outperforming similar implementations in deep-scaled CMOS technologies.

A 94 GHz, 1.4 dB Insertion Loss Single-Pole Double-Throw Switch Using Reverse-Saturated SiGe HBTs

This work demonstrates two 94 GHz SPDT quarter-wave shunt switches using saturated SiGe HBTs. A new mode of operation, called reverse saturation, using the emitter at the RF output node of the switch, is utilized to take advantage of the higher emitter doping and improved isolation from the substrate. The switches were designed in a 180 nm SiGe BiCMOS technology featuring 90 nm SiGe HBTs (selective emitter shrink) with fT/fmax of 250/300+ GHz. The forward-saturated switch achieves an insertion loss and isolation at 94 GHz of 1.8 dB and 19.3 dB, respectively. The reverse-saturated switch achieves a similar isolation, but reduces the insertion loss to 1.4 dB. This result represents a 30% improvement in insertion loss in comparison to the best CMOS SPDT at 94 GHz.

Low phase noise and high output power 367 GHz and 154 GHz signal sources in 130 nm SiGe HBT technology

This paper addresses the design and measurement results of two high frequency signal sources implemented in SiGe HBT technology. The 367 GHz signal source achieves a phase noise of -110 dBc/Hz at 10 MHz offset from the carrier and provides better than -8 dBm of output power. The 154 GHz signal source achieves a phase noise of -87 dBc/Hz at 1 MHz offset from the carrier and generates +7 dBm of differential output power. To the authors knowledge, the 154 GHz oscillator achieves the highest output power among silicon-based signal sources in this frequency range, and the 367 GHz signal source achieves the best phase noise among silicon-based signal sources in this frequency range. These results show the feasibility of implementation of high-performance sub-millimeter-wave circuits in advanced SiGe technology platforms.

A Class-E Tuned W-Band SiGe Power Amplifier With 40.4% Power-Added Efficiency at 93 GHz

A W-band power amplifier with Class-E tuning in a 0.13 μm SiGe BiCMOS technology is presented. Voltage swing beyond BVCBO is enabled by the cascode topology, low upper base resistance, and minimally overlapping current-voltage waveforms. At 93 GHz with 4.0 V bias, the peak power-added efficiency and saturated output power are measured to be 40.4% and 17.7 dBm, respectively. With the bias increased to 5.2 V, the peak power-added efficiency and saturated output power at 93 GHz are measured to be 37.6% and 19.3 dBm, respectively.

Total Ionizing Dose Response of Triple-Well FET-Based Wideband, High-Isolation RF Switches in a 130 nm SiGe BiCMOS Technology

The effects of 63 MeV proton irradiation on the RF performance (insertion loss, isolation, and linearity) of triple-well nFET-based RF switches designed in a 130 nm SiGe BiCMOS technology are investigated. The switches were designed for wide-band operation (1 to 40 GHz) and were required by the application to achieve high isolation (> 35 dB at 40 GHz) with moderate insertion loss (dB at 40 GHz). The RF switch IL improves (S21 increases) at 100 and 500 krad(SiO2), but degrades (S21 decreases) at 2 Mrad(SiO2). P1dB and IIP3 (switch linearity) shows a similar TID response, at 100 and 500 krad(SiO2) dose an increase of ~ 0.4 dBm and ~0.2 dBm, respectively. However, at 2 Mrad(SiO2) both sharply decrease. Standalone RF and dc structures were also irradiated to better understand the underlying mechanisms affecting the switch RF performance. The bias dependence of the radiation-induced change on the measured RF performance of a SPST switch is also analyzed. 10 keV X-ray radiation experiments were conducted on separate dc transistor structures to provide additional insight into the measured impact of total ionization dose on the performance of RF switches.

A hybrid GaN/organic X-band transmitter module

The design and implementation of a compact, flexible and lightweight X-band transmitter (Tx) module based on high-power gallium nitride (GaN) transistor technology and a low-cost organic package made from liquid crystal polymer (LCP) is presented. In-package measurements of the power amplifier (PA) at 8 GHz show a P.A.E.max of >31%, P1dB of 20 dBm and gain of 11.42 dB. A 4×1 patch antenna array was also fabricated on the same platform. Though no thermal management was used, an effective isotropically radiated power (EIRP) in excess of 20 dBm at 10 GHz was measured for the transmitter module, consisting of only a single-stage PA and antenna array, thus demonstrating that even greater performance can be achieved in the future.

A compact, transformer-based 60 GHz SPDT RF switch utilizing diode-connected SiGe HBTs

This work describes the design of a compact 60 GHz SPDT RF switch utilizing diode-connected SiGe HBTs. At mm-wave frequencies, SiGe HBTs demonstrate better Roff/Ron ratios than CMOS and can be used to improve switch performance. A switch topology using a transformer is developed to create a SPDT with a small foot print of 190 μm × 225 μm. The transformer design is discussed and a methodology is presented to optimize the matching components of the switch. The switch is fabricated on a 180 nm SiGe BiCMOS technology platform featuring HBTs with an fT/fmax of 240/260 GHz. The switch achieves 2.7 dB insertion loss and 14 dB isolation at 60 GHz with a P1dB and IIP3 of 13.8 dBm and 23.8 dBm, respectively. This represents a 20% improvement in insertion loss in comparison to a similar 90 nm CMOS switch at 50 GHz. It is also shown that the proposed switch can help enable built-in-self-test (BIST) functionality for transmit-receive modules.

A W-band integrated silicon-germanium loop-back and front-end transmit-receive switch for Built-in-self-test

This paper presents a front-end switch that integrates the ability to provide both loop-back testing and transmit-receive operation. In addition, power detectors are integrated with capacitive couplers to sense the power levels at the transmitter output and the receiver input. The measured results show the power detectors have constant responsivity and can predict the power level within 0.5 dB. These capabilities are added to the front-end switch while maintaining an insertion loss of 2.3-2.5 dB and an isolation of 19.5 dB at 94 GHz.

SiGe Technology as a Millimeter-Wave Platform: Scaling Issues, Reliability Physics, Circuit Performance, and New Opportunities

This paper reviews recent work aimed at a comprehensive assessment of the potential of SiGe technology to support emerging millimeter-wave (mm-wave) and sub-mm-wave integrated circuit applications. Scaling limits, reliability constraints, and the limits of CMOS for mm-wave are addressed, followed by a diverse variety of mm-wave and sub-mm-wave SiGe circuits that are offered as examples of the many opportunities awaiting.