Top-Gate Low-Threshold Voltage $p\hbox{-}\hbox{Cu}_{2} \hbox{O}$ Thin-Film Transistor Grown on $\hbox{SiO}_{2}/ \hbox{Si}$ Substrate Using a High-$\kappa$ HfON Gate Dielectric

Abstract

Copper oxide (Cu <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> O) thin films were grown on SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /Si substrate by pulsed laser deposition under different substrate temperatures. Top-gate Cu <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> O semiconductor thin-film transistors (TFTs) were fabricated with high- κ HfON as gate dielectric. The performance of Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O TFTs was improved due to increased Hall mobility resulting from the decreased scattering of both the ionized defects and the grain boundary for Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O channel films. The <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p</i> -channel pure polycrystalline Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O TFTs ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">W</i> / <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</i> = 500 μm/20 μm) exhibited a low threshold voltage of -0.8 V, an on-off current ratio of 3 x 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> , a saturation mobility of 4.3 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> / V s, and a subthreshold swing of 0.18 V/decade.