Demonstration of Immunity to 400 ◦C Forming Gas Annealing in Oxide Semiconductor Transistor via PostMetallization Annealing

Published

March 18, 2025

Author(s)

Yu-Hsin Kuo, Dylan J. Matthews, Shinichiro N. Muramoto, TaeYoung Song, Chengyang Zhang, Xianduo Zhao, Md S. Rahman, Sanghyun Kang, Andres S. Aguirre, Seung M. Lee, Daewon Ha, Sourav Dutta, Theodore Moise, Jayakanth Ravichandran, Shimeng Yu, Alexander Grutter, Suman Datta, Tania Roy, Asif I. Khan

Abstract

Hydrogen-based annealing processes like forming gas annealing (FGA), widely used in back-end-ofline (BEOL) fabrication, can severely impact the threshold voltage (VTH) and subthreshold swing (SS) stability of amorphous oxide semiconductor (AOS) transistors. We present a novel mitigation strategy using post-metallization annealing (PMA) in oxygen (O2) ambient at 250 ◦C, which effectively shields devices from degradation during subsequent 400 ◦C FGA for 1 hour. A comparative study of devices with and without O2 PMA reveals significant improvements in VTH and SS stability. This approach offers a practical solution for integrating AOS transistors into BEOL technologies.

Citation

IEEE Electron Device Letters

Pub Type

Journals

Keywords

hydrogen, film, SIMS, oxide

Citation

Kuo, Y. , Matthews, D. , Muramoto, S. , Song, T. , Zhang, C. , Zhao, X. , Rahman, M. , Kang, S. , Aguirre, A. , Lee, S. , Ha, D. , Dutta, S. , Moise, T. , Ravichandran, J. , Yu, S. , Grutter, A. , Datta, S. , Roy, T. and Khan, A. (2025), Demonstration of Immunity to 400 ◦C Forming Gas Annealing in Oxide Semiconductor Transistor via PostMetallization Annealing, IEEE Electron Device Letters (Accessed September 29, 2025)