CMOS-Compatible InAlN/GaN HEMTs on Silicon for RF Power Amplifiers in 5G Mobile SoCs

In this work we demonstrated InAlN/GaN High Electron Mobility Transistors (HEMTs) on silicon substrate fabricated with Si CMOS-compatible metallization process for RF power amplifier applications in 5G low power mobile SOCs. The HEMTs exhibited a maximum drain current (
$I_{\text{dmax}}$
) of 1.9 A/mm, a peak transconductance (
$g_{\mathrm{m}}$
) of 490 mS/mm, a cutoff frequency (
$f_{\mathrm{T}}$
) of 215 GHz and a maximum oscillation frequency (
$f_{\max}$
) of 97 GHz. An effective electron velocity of
$1.49\times 10^{7}$
cm/s was extracted through delay time analysis. At a mobile SoC-compatible supply voltage of
$V_{d}=5\ \mathrm{V}$
, the device shows a high maximum output power density (
$P_{\text{outmax}}$
) of 1.24 W/mm, a peak power-added efficiency (PAE) of 45%, and a gain of 16 dB at 5 GHz. These results indicate the great potential of InAlN/GaN HEMTs on silicon for high performance and low-cost RF power amplifiers in 5G mobile SoC applications.