GaN itself comes in two main flavours, GaN on SiC which is ideal for very high power applications and GaN on Si which offers the ability to scale up in wafer diameter, driving costs down as volume rises, exploiting the traditional economies-of-scale offered by CMOS. MACOM expects GaN to disrupt all RF functions and applications.
GaN on Si as a wideband gap semiconductor technology in RF and microwave applications is becoming critical for mainstream commercial applications due to its power density, efficiency and thermal properties. GaN on Si offers 8x the raw power density of GaAs and 4x the raw power density of LDMOS technology. Efficiency ranges from the mid-40s to as much as 70%.
The market potential for GaN is big and the process technology is expected to eventually dominate the high performance RF and microwave market. GaN performance advantages include 5x bandwidth and 2x efficiency over existing products.
Furthermore, GaN is capable of fulfilling all analog functions and applications
GaN on SiC versus GaN on Si
Fundamentally, at a physics level, SiC boules grow 200x to 300x slower than silicon. Thus the cost of producing substrates scales proportionally to production time. For this reason GaN on SiC will remain too expensive for mainstream commercial use. However, it will find use in specialised applications in military and defence and potentially high end communications applications that require relatively high power.
The ability to reduce costs yet benefit from high power density and efficiency lies with GaN on Si. Further, GaN on Si is very complimentary to a silicon roadmap — and is expected to eventually accommodate a lot of CMOS on the die with it.
GaN on Si technology will be driven by power conversion applications, which command unit volumes that are orders of magnitude greater than RF and microwave demand.
According to John Croteau, President and CEO of MACOM, “Put in perspective, a full year’s production for the entire