Silver-insertion induced improvements in dielectric characteristics of the Hf-based film

The capacitor structural Hf-based films (HfAlO) inserted by Ag nanoparticles were fabricated on p-Si(100) substrates by radio frequency Magnetron sputtering, and their microstructures and dielectric characteristics involving the leakage current-voltage (J-V), the capacitance-voltage (C-V) and the capacitance-frequency (C-F), were further investigated. The permittivity of 21.8 at 1 MHz and the leakage current density with 9.5×10-8Å/cm2 at −1 V for the HfAlO film with Ag nanoparticles, are detected and superior to that of the HfAlO film without Ag particles in dielectric characteristics. Furthermore, in order to understand the influences of interface layer on dielectric properties, the Ag-inserted HfAlO film with Pt(100) substrate was also fabricated and compared with the Ag-inserted HfAlO film with p-Si(100) substrate. As a result, the relative lower dielectric constant in the Ag-inserted HfAlO film with p-Si(100) substrate was detected. We therefore deduce that the inevitable interfacial layer between HfAlO and Si substrates plays am important role in dielectric characteristics.