ABSTRACT
This chapter describes two most frequently used active devices in the radio frequency (RF) integrated circuit design, namely the transistor and the PN junction diode. The diode is a unipolar device and conducts a negligible leakage current when reverse biased, i.e., when the cathode's voltage is more than the anode voltage. A diode is a two-terminal semiconductor device and consists of a p-type and an n-type junction. The diode is a unipolar device and conducts a negligible leakage current when reverse biased, i.e., when the cathode's (N-terminal) voltage is more than the anode voltage (P-terminal). Transistors are mainly included in the RF integrated circuit (IC) design for implementing the RF, analog, and digital functionalities. The market share of digital functionalities has been taken over by complementary metal oxide semiconductor (CMOS) transistors as they offer low-power, high-speed, and high-density integration features unlike other transistor types.
