A gate Modulated avalanche bipolar transistor in 130nm CMOS technology

A novel Geiger-mode avalanche bipolar transistor structure is realized in a 130nm, low-voltage CMOS technology. A MOS transistor formed within the base region of the device allows gate modulation of the output pulse rate. In bipolar operation, the device generates Poisson-distributed digital output pulses at rates from 1kHz to 20MHz, linearly related to emitter currents in the range 10nA to 1μA. In MOS operation, the mean pulse rate varies exponentially over 4-5 decades as the gate voltage changes by 300mV and consumes less than 180μA drain-source current. The gate input eliminates the input current of the avalanche bipolar transistor, enabling capacitive sensor interfaces and direct device-level, analogue-digital conversion. The device is fully compatible with low-voltage CMOS circuits and standard digital process steps.