Optical second-harmonic generation study of charge trapping dynamics in HfO_2/SiO_2 films on Si(100)

摘要

Electrostatic-Field-Induced Second Harmonic (EFISH) generation is used to characterize laser-induced charge trapping dynamics in thin HfO_2. films deposited on chemically oxidized P-type Si(100) suhstrates. Wo monitor EFISH generation as a function of time. HfO_2 thickness and post-deposition annealing (PDA). In as-deposited films, the results show that clectrons and holes arc injected and trapped in comparablernamounts, but on different time scales. In annealed films, electron dynamics dominate at all times. Quantitative details depend on film thickness. These results show that time-dependent EFISH generation can provide an in situ, nondestructive diagnostic of charge trapping in thin high-k gate dielectric films.