Composition dependence of the work function of Ta1−xAlxNy metal gates

作者：Husam N. Alshareef, Kiho Choi, H.C. Wen, H.F. Luan, H. R. Harris, Y. Senzaki, P. Majhi, B. H. Lee, R. Jammy, S. Aguirre-Tostado, Bruce E. Gnade, Robert M. Wallace · 发表于：Applied Physics Letters · 年份：2006 · DOI：10.1063/1.2174836 · 被引用次数：39 · 研究领域：Semiconductor materials and devices、Advancements in Semiconductor Devices and Circuit Design、Electronic and Structural Properties of Oxides

It is shown that the work function of Ta1−xAlxNy depends on the electrode and gate dielectric compositions. Specifically, the work function of Ta1−xAlxNy increased with SiO2 content in the gate dielectric, reaching as high as 5.0eV on SiO2; the work function was nearly 400mV smaller on HfO2. In addition, the work function decreased with increasing nitrogen content in the Ta1−xAlxNy metal gate. Increasing Al concentration increased the work function up to about 15% Al, but the work function decreased for higher Al concentrations. Chemical analysis shows that Al–O bonding at the interface correlates with the observed work function values.