Gate-Controllable Electronic Trap Detection in Dielectrics
Sandip Mondal, Tathagata Paul, Arindam Ghosh, V. Venkataraman
Abstract
Gate controllable electronic trap detection method has been demonstrated by regulating the gate potential of MIS devices. This method is based on shift of capacitance-voltage (CV) curve as well as flatband voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FB</sub> ) measure in <; 10 μs due to injection or ejection of electrons through the metal gate. Using this method, an electronic trap energy distribution was measured in the HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> dielectric film and it confirms a maximum number of traps (ΔN <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> ) of 1.7 × 1012 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> corresponding to an energy level (ΔE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">IL</sub> ) of 0.45 eV above silicon conduction band (Si-E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CB</sub> ). In comparison, ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -based MIS devices showed a broader distribution of electronic traps throughout the band gap. However, HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> contained more than 60% traps in deep level compared to 50% in ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , which establishes the effects of material variation.