DEFECT AND COMPOSITION ANALYSIS OF AS-DEPOSITED AND NITRIDED (100)SI/SIO_2/HF_(1-X)SI_XO_2 STACKS BY ELECTRON PARAMAGNETIC RESONANCE AND ION BEAM ANALYSIS

摘要

The defects in the as-deposited and nitrided Si/SiO_2/Hf_(1-x)Si_xO_2 stacks have been analysed by EPR spectroscopy. The interface defects at the Si/SiO_2 section are identical to those in the classical Si/SiO_2 case and their concentration is not influenced by the hafnium silicate layer growth. Asdeposited hafnium silicate layers present in addition a defect located in the near surface region with a high concentration; it shows the characteristics of the EX center in SiO_2 including low temperature hydrogen passivation. In the nitrided samples both the interface defects and the EX center are no longer observed. Additional annealing shows this to be related to a hydrogen passivation during the nitridation. The composition of the as deposited Hf_(1-x)Si_xO_2 layers have been analysed by ion beam analysis. Their thermal nitridation by NH_3 has been investigated as a function of the annealing conditions. The hafnium silicate layers incoporate N up to some at% in the entire layer whereas hafnium oxide layers show no significant nitrogen incorporate into the bulk of the film.