Degradation of polycrystalline HfO2-based gate dielectrics under nanoscale electrical stress

作者：Iglesias V; Lanza M^*; Zhang K; Bayerl A; Porti M; Nafria M; Aymerich X; Benstteter G; Shen Z Y; Bersuker G

来源：Applied Physics Letters, 2011, 99(10): 103510.

DOI：10.1063/1.3637633

• atomic force microscopy
• electric breakdown
• elemental semiconductors
• grain boundaries
• hafnium compounds
• MIS structures
• silicon
• silicon compounds

The evolution of the electrical properties of HfO2/SiO2/Si dielectric stacks under electrical stress has been investigated using atomic force microscope-based techniques. The current through the grain boundaries (GBs), which is found to be higher than thorough the grains, is correlated to a higher density of positively charged defects at the GBs. Electrical stress produces different degradation kinetics in the grains and GBs, with a much shorter time to breakdown in the latter, indicating that GBs facilitate dielectric breakdown in high-k gate stacks.

• 出版日期2011-9-5
• 单位北京大学