We report on the impact of H2 high pressure annealing (H2-HPA) on a Y-doped ZrO2 (Y-ZrO2)/GeOx/Ge gate stack. In this paper, compared to conventional forming gas annealing (FGA), the H2-HPA increased the k-value of the Y-doped ZrO2 gate dielectric to as high as 47.8 by enhancing the crystallization of the Y-ZrO2. This process can achieve an aggressively scaled equivalent oxide thickness (EOT) of 0.57 nm with an extremely low gate leakage current (Jg) of 4.5 × 10-6 A/cm2. In addition, the H2-HPA effectively passivated the dangling bonds and reduced the interfacetrap density (Dit) to as low as 3.4 × 1011 eV-1cm-2. The Ge pMOSFETs of the Y-ZrO2 with H2-HPA led to a ∼ 70% improvement in the effective hole mobility compared to the counterpart device with the conventional FGA. The device with H2-HPA also showed an improved subthreshold swing (SS) value of 93 mV/dec compared to that with the FGA(135 mV/dec).
- Equivalent oxide thickness (EOT)
- Gate leakage current
- Interface properties
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering