Rapid hydrogen annealing for enhanced device performance and reduced thermal budget

Abstract As metal–oxide–semiconductor field-effect transistors (MOSFETs) have been aggressively scaled down, the gate oxide has also been thinned to suppress short-channel effects (SCEs) and increase gate capacitance. However, this thinner oxide is more susceptible to electrical stress and reliability degradation. To improve the gate oxide quality, conventional forming gas annealing (FGA) with hydrogen (H 2 ) ambient diluted with nitrogen (N 2 ) at 400 °C for at least 30 min has been widely employed. However, FGA process conditions are unsuitable for advanced device fabrication, including monolithic three-dimensional integrated circuits (M3DICs), ultra-scaled system devices, and flexible or stretchable electronics, as the high thermal budget induces undesirable thermal damage and process variability. As an alternative, we propose rapid hydrogen annealing (RHA), conducted at 250 °C for 3 min, which significantly reduces the thermal budget compared to conventional FGA. The effect of RHA is evaluated based on silicon MOSFETs and their extracted device parameters.