Determination of funnel length from cross section versus LET measurements

This paper proposes an empirical model and method for determining the funnel length from heavy ion upset cross section as a function LET data. It is valid for bulk technologies having a lightly doped epi region over a heavily doped substrate region. Definition of the funnel length is necessary in order to define the heavy ion track length along which charge is collected. Knowing the track length and the threshold LET for upset, the critical charge can be calculated. Critical charge as well as sensitive volume dimensions for upset are required input parameters for upset calculation codes such as CREME. The more accurate the critical charge calculation, the more accurate the calculated upset rate