48.8 mW Multi-Cell InP HBT Amplifier with On-Wafer Power Combining at 220 GHz

We report 220 GHz Solid State Power Amplifier (SSPA) using a 250nm Indium Phosphide HBT technology. Amplifiers reported include designs having 2 and 4 power combined cells. The 4-cell amplifiers exhibited 10 dB small signal gain and 48.8 mW of output power with 4.5 dB gain at 220 GHz. These amplifiers have a 3-dB small signal bandwidth of greater than 48 GHz. A 5-μm thick BCB microstrip wiring environment with 4 levels of interconnects allowed for low-loss transmission lines, mm-wave tuning structures, and dense interconnects within each cell. The 2-cell amplifiers provide 10.9 dB small signal gain at 220 GHz with a 3-dB bandwidth of greater than 42 GHz and 26.3 mW of saturated output power at 208GHz.