What are the advantages of GaN on Silicon for MMICs?

The economies of scale made possible by GaN’s propagation into commercial 4G LTE wireless infrastructure can also enable GaN’s migration into the MMICs market, where it can help system designers achieve higher levels of functionality and device integration for next-generation 5G systems.

The sheer density of massive MIMO antenna configurations – scaling as high as 256+ transmit and receive elements in a single 5G basestation – puts a premium value on available PCB space, particularly at higher frequencies. To meet this challenge, multifunction MMICs are supplanting discrete ICs and single-function MMICs in 5G basestation designs. 

In addition to the space savings benefits that multifunction integration helps to drive, costs can be lowered through a reduction in individual die packaging, design complexity, testing and assembly labor. Reductions in the number of interfaces can improve overall mechanical reliability.

Against this backdrop, GaN on Si’s successful penetration into the RF commercial semiconductor marketplace comes at a fortuitous time. Its scalability to 8 and 12 inch silicon wafers poises it to enable cost efficiencies that are well out of reach for GaN on SiC, at power densities that can’t be achieved with LDMOS – upward of 4X to 6X more power per unit area. 

Bridging the gap between these two key attributes, GaN on Si is further distinguished by its potential to integrate increased functionality at the silicon level, yielding additional space optimization for ultra compact MMICs. Its silicon substrate supports homogenous integration of GaN devices and CMOS-based devices on a single chip – a capability that GaN on SiC can’t provide due to the inherent process limitations. This opens the door to multifunction, digitally-assisted RF MMICs that can incorporate on-chip digital control and calibration, on-chip power distribution networks, and more.