BEOL-Compatible IGZTO Thin-Film Transistors with Ultra-High Positive Bias Stress Stability for Advanced Electronics

This work explores the impact of channel thickness (T<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CH</inf>) on the positive bias Stress (PBS) of tin-doped Indium Gallium Zinc Oxide (IGZTO) thin-film transistors (TFTs). Thicker T<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CH</inf> shows significantly reduced threshold voltage shifts <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\boldsymbol{\Delta}\boldsymbol{V}_{\mathbf{th}})$</tex> under prolonged bias stress. Notably, transistors with a 15 nm T<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CH</inf> exhibit a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\boldsymbol{\Delta} \boldsymbol{V}_{\mathbf{th}}$</tex> of 7.77 mV after 1000 seconds under a stress field of 4 MV cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup>. These findings underscore the importance of T<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CH</inf> optimization in mitigating PBS effects, offering insights for developing stable and high-performance IGZTO TFTs for advanced electronic applications.