Abstract
The effects of film composition and postnitridation annealing on band gap and valence band offset were examined in nitrided Hf-silicate films prepared using direct plasma nitridation. Regardless of the composition of Hf-silicate films, the band gap characteristics were similar after direct plasma nitridation (4.5±0.1 eV) and postnitridation annealing (5.6±0.1 eV). The decrease in band gap after direct plasma nitridation was caused by the formation of Si-N and Hf-N bonds, while the recovery of band gap by postnitridation annealing was influenced by the dissociation of unstable Hf-N bonds. The difference in valence band offset was strongly related to the chemical states of Si-N bonds.
Original language | English |
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Article number | 022907 |
Journal | Applied Physics Letters |
Volume | 92 |
Issue number | 2 |
DOIs | |
State | Published - 2008 |