Tunable Electronic Trap Energy in Sol-Gel Processed Dielectrics

Abstract

We demonstrate the electronic trap energy distribution (ΔE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">IL</sub> ) in the wide bandgap, nonconventional aluminum oxide phosphate (ALPO) dielectrics. The trap energy distribution has been measured by using the gate injection high-speed capacitance-voltage measurement technique and verified through conventional deep-level transient spectroscopy. The electronic trap energies in ALPO dielectrics were found to be influenced and, hence, tunable by the irradiation temperature. The nonirradiated dielectric film (NI-ALPO) displayed the maximum number of electronic traps at an energy level of 0.2 eV below the conduction band of silicon (Si-E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CB</sub> ). On the other hand, the dielectric film irradiated at 200 °C confirmed the highest number of traps at the location of 0 eV and at the same energy level of Si-E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CB</sub> . In addition, the NI-ALPO dielectric contained over 90% of traps in the deep level of the bandgap (below Si-E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CB</sub> ). In contrast, the ALPO film irradiated at 200 °C accommodated a limited number of traps (~75%) at the deep level of the bandgap.