GaAs RF Devices: Benefits & Top Manufacturers

Introduction : From the mobile phone in your pocket to the complex phased array antennas enabling 5G mmWave and satellite communications, GaAs devices are ubiquitous. It is the material of choice when engineers need a perfect balance of high frequency performance, extreme linearity and ultra low noise.

What is a GaAs RF Device?

Gallium Arsenide (GaAs) is a compound semiconductor made from gallium and arsenic. Compared to traditional Silicon (Si), GaAs possesses a much higher electron mobility. Hence electrons can move through the material much faster. This makes it highly sensitive and incredibly efficient at processing very fast, high frequency signals.

GaAs is primarily used to fabricate Monolithic Microwave Integrated Circuits (MMICs). The two most common transistor technologies built on GaAs are pHEMT and HBT as described below.

• pHEMT (Pseudomorphic High Electron Mobility Transistor): Renowned for its exceptional low noise characteristics and high frequency switching.

• HBT (Heterojunction Bipolar Transistor): Known for its high linearity, excellent phase noise characteristics and efficient power handling at medium power levels.

Key benefits of GaAs

Following are some of the advantages of GaAs in RF engineering.

1. It offers exceptionally low noise performance. GaAs pHEMTs are used for LNAs because they introduce virtually zero electronic noise (i.e. ultra low Noise Figure) while boosting the signal. This make them indispensable in radar receivers, deep space telemetry and 5G base stations.
2. GaAs offers incredibly high linearity (i.e. high OIP3). This is very useful where signals are having high PAPR and we need amplifiers that will not distort the waveform.
3. Due to its high electron mobility, GaAs can easily operate well into the millimeter wave (mmWave) spectrum.
4. Unlike silicon, the GaAs substrate is naturally semi-insulating. This provides excellent electrical isolation between different components on the same chip.
5. While GaN is superior for sheer power, GaAs is a highly mature, high yield manufacturing technology. For low to medium power applications, GaAs is significantly more cost effective to produce than GaN.

Key manufacturers of GaAs RF Devices

Summary:

GaAs is used in wireless system requiring to listen to faint signal in a noisy environment as well to transmit highly complex data stream without distortion. As phased array systems for 5G, 6G and satellite constellations become more prevalent, the demand for highly integrated, low noise and cost effective GaAs MMICs will only continue to grow.