Impact of Oxide Thinning at the LOCOS Edge of MOS Capacitors on Constant Current Stress

The oxide thinning at the field oxide edge significantly affects the oxide reliability. Statistical analysis of charge to breakdown shows that dielectric failure occurs in the corners rather than at the edges of MOS capacitors. The dependence of QBD on Jinj is sensitive to oxide thinning at the LOCOS edge. This limits the current density during accelerated tests in order to achieve reliable results.