A 280 GHz (x8) Frequency Multiplier Chain in 250 nm InP HBT Technology

We report a 280 GHz x8 frequency multiplier chain in 250 nm InP HBT technology. Emitter coupled pair in push-push configuration act as a balanced frequency doubler. The x8 frequency multiplier chain consists of three cascaded frequency doublers. Passive transformers are used to generate single-ended to differential conversion. At 280 GHz, the multiplier chain generates -0.6 dBm output power with 3-dB bandwidth of 48 GHz with input power of -2 dBm at 35 GHz. The unwanted harmonics are suppressed by more than 28 dBc over the frequency range of interest. It consumes 112 mW of DC power and occupies 0.4 mm
²
of the chip area. To the authors’ knowledge, these results demonstrate record spectral purity for H-band frequency multipliers working around 280 GHz with low DC power consumption.