By now, most in the RF/microwave community are familiar with gallium-nitride (GaN) technology and the benefits it can offer. The utilization of GaN technology continues to increase, as many applications are taking advantage of its performance enhancements. In comparison with other device technologies such as gallium-arsenide (GaAs), GaN offers several improvements in performance. Because GaN technology outperforms other device technologies in several aspects, the use of GaN is becoming more widespread.
In the early days of GaN, it seemed like the technology would only be suitable for expensive military applications. However, as the technology has matured and manufacturing costs have decreased, GaN is now being employed in a wide range of applications. Some of these applications include wireless infrastructure, radar, and satellite communications (satcom). GaN devices are available in both packaged and die form.
Satcom is one arena where GaN technology is playing a prominent role. Manufacturers of solid-state power amplifiers (SSPAs) are now using high-power GaN devices to achieve high power levels at high frequencies. In the past, high-power GaAs devices were widely used to design these SSPAs. Today, however, many high-power GaN devices intended for these applications are available on the market. These devices provide the performance required by these SSPAs. Although many SSPAs still utilize GaAs devices, GaN is taking control of this segment.
Although power amplifiers are the predominant application for GaN technology today, other applications can also benefit from GaN. Low-noise amplifiers (LNAs) are one example. GaN LNAs are capable of handling very high input signal levels without incurring any damage. In many front-ends, a limiter is placed before the LNA. This limiter protects the LNA from high incident signal levels. Since GaN LNAs can already withstand high input signal levels, the limiter can be removed altogether, which improves the overall noise figure. New GaN LNAs have recently been released that provide this capability.
Several companies have released new GaN products in the last few months alone. Freescale Semiconductor recently released its first GaN power transistor for cellular base stations. Custom MMIC has expanded its portfolio with the release of a new GaN LNA. And Qorvo also recently released new GaN products for both satcom and radar applications. These are just a few examples of the recent activity that has occurred in the GaN marketplace. With performance requirements continuing to increase, we can expect to see more activity in the very near future.