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.