Al/La_2O_3 Analysis of Post Metallization Annealed MISFETs by XPS

摘要

La_2O_3 gated MISFETs with various heat treatments were fabricated and measured. High effective mobility was obtained using a Post Metallization Anneal (PMA) with Al gate electrodes. XPS analysis showed the formation of a thin Al_2O_3 interface layer between the Al and La_2O_3 during the annealing. The formation of the Al_2O_3 layer increased the EOT and shifted the flatband shift in the positive direction. The improvement of the effective mobility can be explained by less formation of oxygen vacancies.