The conversion model of low dose rate effect in bipolar transistors

Physical model of the ELDRS in bipolar transistors is presented. Basis of the model is the assumption that there´re shallow and deep radiation-induced traps in the oxide which are converted to the interface traps with time constants, corresponding interface trap build-up at high and low dose rates. Excess base current is calculated with use of convolution integral for exponential and power response functions. The model provides well agreement between calculation results and published experimental data. The fitting parameter extraction technique is discussed.