Hydrogen induced positive charge in Hf-based dielectrics

作者：Zhao C Z; Zhang J F^*; Zahid M B; Efthymiou E; Lu Y; Hall S; Peaker A R; Groeseneken G; Pantisano L; Degraeve R; De Gendt S; Heyns M

来源：Microelectronic Engineering, 2007, 84(9-10): 2354-2357.

DOI：10.1016/j.mee.2007.04.096

• positive charges
• instability
• hydrogenation
• HfO2
• Hf-silicates
• high-k dielectrics

This work investigates the anneal-induced positive charge in Hf-based dielectrics. It is found that anneal in forming gas produces substantially more positive charge than that in N-2 at 500 degrees C, indicating that hydrogen is a reactant for the positive charging. Positive charging is thermally accelerated and can occur in both HfO2 and Hf-silicates. Nitridation of either interfacial layer or whole dielectric stack enhances the positive charging significantly. These positive charges have a large sample-to-sample variation and are stable. For the first time, both mobile and fixed charges are simultaneously observed for Hf-stacks.

• 出版日期2007-10