Semiconductor components for hyperfrequencies

The aim of this article is to present the various semiconductor components used in microwave systems. These components can be divided into four groups.

1) Discrete non-linear components (Schottky diodes, PINs and varactors) that enable microwave signals to be processed by modifying their amplitude (attenuators, modulators), frequency or phase (detectors, mixers, multipliers, phase shifters).

2) Discrete components for microwave power generation: these are mainly avalanche and transit time diodes and Gunn effect diodes.

3) Three-pole discrete components (field-effect transistors or bipolar transistors) that enable not only low-noise amplification or power amplification of signals, but also microwave power generation (oscillators).

4) Monolithic microwave integrated circuits, which combine various active and passive components on a single semiconductor substrate to perform a complete function.

The physical principles governing the operation of these various components will be clarified, and a state of the art of the performances obtained to date for both laboratory and commercial components will be given in terms of limiting frequencies, power, efficiency, gain, noise factor, etc.