Compared with GaAs, silicon or other traditional semiconductor materials, GaN will shine in 5G network applications, such as high frequency and small base stations with limited size. As shown in the figure below, the enhancement of wireless networks will drive many technological advances as the standard evolves to 5G.
When it comes to emerging mmWave standards, GaN has clear advantages over current technologies. GaN is able to deliver higher power density, providing multiple benefits:
- Reduced current consumption
- Improved system efficiency
We have already seen the benefits of GaN in 4G base stations, where it has already started replacing silicon LDMOS. For 5G, GaN’s ability to operate in the high-frequency range will help it evolve from base stations to small cell applications and into mobile devices.
Beyond infrastructure: GaN in mobile phones
The first GaN applications were developed for high-power military uses, such as radar or anti-IED jammers, and then gradually expanded to commercial base stations and cable TV broadcasters. The typical operating voltage range for these applications is 28 to 48V.
However, the average voltage for handheld devices ranges from 2.7 to 5 V. Therefore, to operate GaN at these low voltage levels, we need to look into different kinds of devices. GaN devices using alternative materials are being developed to operate effectively at low voltages.
Qorvo develops GaN for 5G
As shown in the figure below, Qorvo currently has a broad range of production-qualified GaN foundry processes that can be used to manufacture products for 5G applications:
-
Higher voltage, lower frequency: As frequencies decrease, our 0.25 μm high voltage technology, QGaN25HV, comes into play. QGaN25HV enables us to go up to 48 V with our 0.25 μm device, achieving high gain and power efficiency. QGaN25HV is ideal for 5G base stations heading towards 6 GHz. At lower 4G frequencies between the L and S bands, our highest power density 0.5 μm technology can reach 10W per mm.
What advantages can GaN processes bring to 5G mobile phones? As we have seen, as frequency standards get higher and higher (Ka-band or millimeter wave), low-voltage GaN processes need to be further developed.
Solving the packaging and cooling challenges of GaN and 5G
The final step in applying GaN to 5G lies in advanced packaging technology and thermal management. GaN devices for high-reliability military applications are generally packaged in ceramic or metal; however, commercial 5G network infrastructure and mobile phones require smaller, lower-cost over-molded plastic packages to compete with existing silicon-based LDMOS or GaAs devices in plastic packages. Similarly, mobile phones focus on low-cost modules, including GaN combined with other technologies, which are not different from current products, but also require very compact and efficient millimeter-wave materials and devices.
The infrastructure challenge is to develop the right package that maintains RF performance while addressing thermal management issues. The higher power density of GaN (3x to 5x, or even 10x that of GaAs) presents subsystem package designers with challenging thermal and mechanical issues.
Our engineers must balance three requirements: RF performance, thermal management, and low cost. Qorvo's plastic overmolded packages feature enhanced thermal management for GaN, including a heat spreader built into the package base.
Products in plastic packages also meet stringent environmental standards, such as JEDEC standards for temperature, humidity and bias compliance. This gives customers assurance that our products have the long-term reliability required for 5G applications, whether high frequency, high power or low voltage requirements.
Although there is still a long way to go to achieve 5G, Qorvo is already developing the corresponding process technology and packaging technology to promote customers' 5G applications. GaN is bound to play an exciting and key role in the 5G landscape.
提升卡
变色卡
千斤顶