Study of dielectric-breakdown-induced dopant redistribution based on MOSFET diode I-V measurement

During the evolution of dielectric breakdown (BD) in a metal-oxide-semiconductor field-effect transistor (MOSFET), the substantially high localized temperatures (which could exceed the silicon melting point) in the vicinity of the BD spot possibly cause dopants to be redistributed. The diode I-V characteristics at the substrate-source/drain junction of a MOSFET serve as one of the useful methods in studying the dielectric-BD-induced dopant redistribution. The post-BD MOSFET diode current measured in the reverse bias as well as the low-voltage region of the forward bias was found to increase significantly as progressive BD (PBD) evolves. The simulation results associated with the dopant redistribution are in good agreement with the experimental measurements. In addition, as compared with the simulation results associated with the Si/SiO₂ interfacial states, our study further confirms that the dielectric-BD-induced dopant redistribution is one of the dominant mechanisms responsible for the change in the post-BD MOSFET diode I-V characteristics.