Effect of Passivation on BEOL-Compatible Oxide Semiconductor Transistor

This study has demonstrated the scalability of BEOL- compatible copper oxide-based TFT. At a temperature of 300 °C, pure phase <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Cu₂O</tex> thin film is synthesized via applying oxygen annealing on sputtered metallic Cu. Additionally, <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">A1₂O₃</tex> passivation by atomic layer deposition is observed to suppress off-state leakage by 2 orders of magnitudes. Moreover, the scalability is demonstrated by the successful fabrication of a 6nm thin film <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Cu₂ O</tex> TFT. The role of passivation is examined through PBS test.