Modulation of the band offsets between La_2Hf_2O_7 and fully depleted SiGe on insulator by NH_3 treatment

摘要

Band alignments of La_2Hf_2O_7 (LHO) films grown on fully depleted SiGe on insulator (FD SGOI) substrates have been investigated by x-ray photoelectron technique. The valence and conduction band offsets for LHO/FD SGOI systems are determined to be 3.25 and 1.49 eV, respectively. Such asymmetric band alignment can be modulated to be quite symmetric by the surface nitridation of FD SGOI using NH_3 treatment. The impact of NH_3-treatment temperature on band offsets is also investigated.