Theoretical and experimental investigation of temperature-dependent avalanche multiplication in InP-based heterojunction bipolar transistors with InGaAs/InP composite collector

The temperature-dependent collector breakdown behavior in InP HBTs with InGaAs/InP composite collector has been investigated. A detailed modeling of the temperature-dependent breakdown behavior in InP/InGaAs composite collector to quantitatively verify the experimental data was carried out. It has been found that, although the variation of impact ionization coefficient due to the change of temperature may affect the device breakdown, the temperature-dependent breakdown behavior observed in InGaAs/InP composite collector could be mainly due to the carrier transport in the InGaAs region. As temperature is increased, the increase in the contribution of InGaAs layer to the junction breakdown due to the reduction of electron velocity v_e(T) and relaxation time τ_e(T) could be the root cause of the reduction of junction breakdown voltage.