Low-Temperature Deuterium Annealing for HfO₂/SiO₂ Gate Dielectric in Silicon MOSFETs

Abstract

In this study, low-temperature deuterium annealing (LTDA) at 300 °C is proposed to enhance both the performance and reliability of silicon-based high-k metal gate (HKMG) MOSFETs. A comparative study with hydrogen (H2) annealing under identical conditions is conducted to evaluate the specific impact of deuterium (D2). Comprehensive DC characterizations and evaluations of stress immunity under hot-carrier injection (HCI) and positive bias stress (PBS) conditions, are performed. The results confirm that even at a low temperature of 300 °C, D2 has a more substantial effect on device performance and reliability compared to H2. This study provides a guideline for reducing the annealing temperature in the fabrication of HKMG MOSFETs.

Keywords

• Annealing
• high-k dielectric
• hot-carrier injection (HCI)
• low-temperature deuterium annealing (LTDA)
• MOSFETs
• positive bias stress (PBS)