Interface properties of annealed and nitrided HTO layers

Non-contact measurements of interface state density and oxide charge were c ompared to surface recombination velocity measurements for their ability to provide a characterization of oxide-silicon interfaces. High-temperature d eposited oxide (HTO) layers were used as the test vehicles. Both techniques are shown to agree quite well with each other and with the traditional cap acitance-voltage technique. From the point-of-view of process characterizat ion, interface State density is very high in as-deposited films, it is stro ngly reduced by annealing or nitridation and it is increased again by reoxi dation. SIMS nitrogen profiles show that in nitrided HTO layers interface s tate density is strongly related to nitrogen concentration at the oxide-sil icon interface. (C) 2001 Elsevier Science B.V. All rights reserved.