We investigated the flat band voltage (VFB) modulation by insertion of lanthanum oxide (La2 O3) into hafnium oxide (HfO 2) gate dielectrics. The properties of La2 O3 / HfO2 nanolaminates were precisely modulated by controlling the position of La2 O3 layer at bottom, middle, or top using atomic layer deposition. When the La2 O3 layer was positioned closer to the interface (bottom), the reduction in VFB shift was more effective than the other two cases (middle and top). From our experimental results, we propose that the main mechanism of VFB modulation using La 2 O3 layer is dipole moment formation at an interfacial layer between high k gate dielectric and Si substrate.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)