MODELING THE REVERSE BASE CURRENT PHENOMENON DUE TO AVALANCHE EFFECT IN ADVANCED BIPOLAR-TRANSISTORS

Reverse base current (RBC) phenomenon results from avalanche multiplication process can occur in advanced bipolar transistors in which the collector doping concentration is in the order of 1017 cm-3. It has been shown recently that the RBC effect can be used to design an extremely small SRAM cell consisting of only one bipolar transistor and one MOS transistor. Based on device physics, we have successfully modeled the RBC characteristics. The model developed requires only physical parameters, thus allowing circuit designers to estimate the device performance under avalanche operation prior to the actual device fabrication. Experimental data reported in the literature are included in support of the model. © 1990 IEEE