Silicon MOSFET technology for RF ICs

Application of silicon MOSFET technologies to high frequency RF transceiver functions will be presented. Starting with a description of the high frequency characteristics of silicon MOSFETs designed specifically for RF applications. These applications include several RF functions where silicon MOSFETs have not traditionally been used such as low noise amplifiers, balanced mixers, RF switches and integrated power amplifiers. Finally a description of the performance trade-offs associated with silicon BJT (Bipolar Junction Transistor) technology are given along with an evaluation of how BiCMOS (Bipolar-CMOS) technologies can sometimes serve as the best solution to RF IC designs. Another silicon MOSFET device well suited to RF applications is the Thin Film Silicon on Insulator (TFSOI) device [2] shown in Figure 2. This transistor is constructed in the same manner as the device in Figure 1 except that a layer of insulating dielectric is now present between the epi and the substrate. The buried oxide insulator dramatically reduces the source-substrate and drain-substrate capacitance that is inherent to classic MOSFET device architecture and i prohibits the use of a low impedance source ground contacts. 1 I \