Extraction of eleven model parameters for consistent reproduction of lateral bipolar snapback high-current I-V characteristics in NMOS devices

A series of literature models originally devoted to the second breakdown trigger current I_t2 in a grounded-gate NMOS transistor can further find promising potential in handling high-current I-V due to lateral bipolar snapback. This is achieved primarily by building significant linkage between bipolar current-gain β-related parameters: 1) the collector-to-base junction voltage dependencies A₁ and A₂ of the medium-level injection β roll-off factor; 2) the high-level β roll-off factor A₃; and 3) the collector-to-base junction voltage dependencies A₄ and A₅ of the collector corner current at the onset of high-level β roll-off. The new parameters A₁ to A₅ enable a consistent I-V solution along with other existing six model parameters such as the substrate resistance R_sub and its conductivity modulation factor A_τ, the impact ionization coefficients K₁ and K₂, and the emitter series resistance R_e and collector series resistance R_c . Parameter extraction except R_c is thoroughly performed using only the parametric analyzer, and opposed to the traditional procedure, impact ionization coefficients and current gains are all assessed without entering the snapback regime. Remarkably, not only excellent agreements are obtained, but also bipolar snapback I-V measured under the current pulsing condition can be separated into two distinct parts: medium- and high-level injection region. This is quite effective under R_e=R_c. Series resistance, although having very low value, is not to be absent under the high-level injection conditions