Structural and dielectric properties of Ti and Er co-doped HfO2 gate dielectrics grown by RF sputtering

Abstract This work reports on the structural and dielectric properties of high-k Ti and Er co-doped HfO 2 (HfTiErO x ) gate dielectrics deposited on Si(1 0 0) substrates by RF sputtering. Results indicate that the capacitance value of HfTiErO x gate dielectric at 100 °C substrate temperature is higher and exhibits a lower hysteresis voltage as well as interface trap density compared to HfO 2 , HfErO x and HfTiO x films at the same conditions in capacitance–voltage ( C – V ) curves. Furthermore, the structural, chemical compositions and photonics properties of these films have been explored by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Photo luminous (PL) measurements. The results are well attributed to crystalline HfTiErO x microstructure thus new chemical bonding of Hf Ti Er O may exit. PL spectra of all the prepared samples exhibit peaks in range of ∼2.82 to ∼3.03 eV which is attributed to oxygen vacancies.