Effective control on flat band voltage of epitaxial lanthanide oxide based metal oxide semiconductor capacitors by interfacial carbon

作者：Laha Apurba^*; Fissel A; Osten H J

来源：Applied Physics Letters, 2013, 102(20): 202902.

DOI：10.1063/1.4807588

Present work addresses the issue of flat band voltage instability engendered by the presence of large number of fixed charges and interface traps at and close to the interface of metal oxide semiconductor capacitors. We show that submonolayer of C incorporation onto Si surface prior to epitaxial lanthanide oxides (Ln(2)O(3): Gd2O3, Nd2O3) deposition can significantly improve their electrical properties. Ultraviolet photoelectric spectroscopy shows that most of the intrinsic surface states that stem from the dangling bonds on Si surface disappear after passivation with C. The flat band voltage of Pt/Gd2O3/Si MOS capacitors can be tuned in a controlled manner by systematic incorporation of C onto Si surface, effectively at Gd2O3-Si interface.