Record high-performance RF devices in an advanced FDSOI process enabling integrated Watt-level power amplifiers for WiFi and 5G applications

Abstract

High-voltage RF active and passive devices, including LDMOS, fringe capacitors, transformers and inductors with good RF performance, are required for building integrated RF power amplifiers at Watt-level in high-performance cost-effective RF front-end ICs. This paper reports, for the first time, a novel 3.3V / 5V RF-LDMOS with a cutoff frequency beyond 100GHz, designed and fabricated without any additional dedicated mask in an advanced sub-28nm node FDSOI process. For passive devices, by combining the novel RF design with an RF-compatible metal stack, accurate EM simulation, and 4-port RF characterization, a record high Q-factor for a 7V-fringe capacitor, a 2-way transformer and 8-shaped inductors are obtained. The RF performance of these high-voltage (HV) capable devices is comparable to best-in-class devices in RF-HV-centric non-CMOS processes, e.g. SiGe and GaAs. This enables highly integrated cost-effective power amplifiers for both WiFi (5GHz) and 5G (28GHz) applications.