Extended Mie-Gruneisen molecular model for time dependent dielectric breakdown in silica detailing the critical roles of O-SiO3 tetragonal bonding, stretched bonds, hole capture, and hydrogen release

An extended Mie-Gruneisen molecular model is presented, which describes a bond-breakage process for O-Si=O-3 tetragonal molecules in silica and the trap-generation process that occurs during time dependent dielectric breakdown (TDDB) testing. This quantitative molecular model correctly describes important physics routinely reported for silica TDDB testing: the generation of E' centers, a breakdown strength of E-bd similar to 15 MV/cm, an effective dipole-moment range of p(eff)=7-13e angstrom, and a zero-field activation energy range for bond breakage of Delta H-o*=1-2 eV. The bond-breakage/trap-generation mechanism is shown to occur when the Si ion transitions from its primary energy minimum (with fourfold coordination) to a secondary saddle point (with threefold coordination). The molecular model also shows clearly that current induced hole capture and hydrogen release can play critically important roles in the TDDB process. (C) 2006 American Institute of Physics.