Effect of N2-Anneal Temperature on Silicon Nitride Film: (I) Time-Dependent Dielectric Breakdown and ESR Evaluations

Abstract

Silicon Nitride (SiN) film has been used as insulating material in many electronic devices such as capacitors and memories. This report electrically evaluated the effect of N2 annealing temperature on accidental charge breakdown (Qbd) of LP-CVD SiN film using the time-dependent dielectric breakdown (TDDB) test method. The variation and number of the defects, existing in the SiN film, in the oxide layer between SiN film and Si substrate, and at the SiN film/Si interface, were investigated using an electron spin resonance (ESR) to reveal the defect behavior related to triggering Qbd. At Si surface (Pb center), dangling bond density reached a maximal peak at an annealing temperature of 900°C, and those in SiO2 film (E′ center) and SiN film (K center) were increased with increasing temperature above 1000°C. These two types of phenomena showed good agreement with the Qbd occurrence dependency on the annealing temperature, as the detected by TDDB.