Electrically detected magnetic resonance of ion-implantation damage centers in silicon large-scale integrated circuits

Abstract

We used electrically detected magnetic resonance to study the microscopic structure of ion-implantation-induced point defects that remained in large-scale Si integrated circuits (Si LSIs). Two types of defects were detected in the source/drain (n+-type) region of 0.25-μm-gate-length n-channel metal oxide semiconductor field-effect-transistors on LSIs: (i) a spin-1 Si dangling-bond (DB) pair in divacancy–oxygen complexes (DB–DB distance, R≈0.6 nm); and (ii) a series of larger Si vacancies involving distant Si DBs (R⩾1.4 nm). These vacancy-type defects were much more thermally stable in Si LSIs than those in bulk Si crystals. We suggested two physical mechanisms for this enhanced stability: internal mechanical stress and oxygen incorporation in the active regions of LSIs. After examining the relationship between the defects and current–voltage characteristics, we concluded that these defects are distributed in the near-surface n+-type region close to the gate and that they are the source of the gate-induced drain leakage currents.