220-GHz High-Efficiency Power Amplifiers in 250-nm and 130-nm InP HBT Technologies Having 14.4-25.0% PAE and 40-60 mW $\mathrm{P}_{\text{out}}$

We report two 220-GHz solid-state power amplifiers (PA, SSPA) having high output power
$(\mathbf{P}_{\mathbf{out}})$
and record power-added-efficiency (PAE). The first amplifier (PA-1) uses a 250-nm InP HBT technology. The
$\mathbf{s}_{\mathbf{21}}$
gain is 19.6-dB. DC power dissipation is 230-mW
$(\mathbf{P}_{\mathbf{DC}})$
. From 215–225 GHz, the saturated output power
$\mathbf{P}_{\mathbf{sat}}$
is 35.9-41.2
$\mathbf{mW}(\mathbf{1.12}-\mathbf{1.29}\ \mathbf{W}/\mathbf{mm}$
RF power density) with 7.2-7.5 dB gain and peak 12.5-14.4% PAE. The 5-dB gain compression
$\mathbf{P}_{\mathbf{out}}(\mathbf{OP}_{\mathbf{5}\mathbf{dB}})$
at 220-GHz is 29.7-m W with 12.4% PAE. PA size is
$\mathbf{0.264}-\mathbf{mm}^{\mathbf{2}}$
. The second amplifier (PA-2) uses a 130-nm InP HBT technology. The
$\mathbf{s}_{\mathbf{21}}$
gain is 14.8-dB.
$\mathbf{P}_{\mathbf{DC}}$
is 156-mW. From 217.5-225 GHz,
$\mathbf{P}_{\mathbf{sat}}$
is 45–50 mW (1.41-1.56 W/mm) with 6.2-7.2 dB gain and peak 25.0% PAE. The
$\mathbf{OP}_{\mathbf{5}\mathbf{dB}}$
at 220-GHz is 47.2-mW with 25.0% PAE. At an elevated HBT bias voltage, higher
$\mathbf{P}_{\mathbf{out}}$
is demonstrated but with small reductions to PAE. PA size is
$\mathbf{0.192}-\mathbf{mm}^{\mathbf{2}}$
. This work represents world-class, high-efficiency solid-state power from two InP HBT technology nodes, where record 25% PAE with 46-mW
$\mathbf{P}_{\mathbf{out}}$
is demonstrated at 220-GHz.