Tetravalent doping in hafnium-zirconium oxides to lower polarization switching voltage

• DOI: 10.1109/vlsi-tsa54299.2022.9771018
• Publication Date: 2022-05-10T19:53:21Z
• Authors: Kisung Chae; Andrew C Kummel; Kyeongjae Cho
• Keywords: Hafnium; Tetragonal crystal system

Effects of tetravalent doping (Si, Ge, Ti, Ce) are investigated in hafnium-zirconium oxide (HZO). Density functional theory is employed to demonstrate: 1) relative stability change, 2) polarization switching energy barrier, and 3) electronic structures doped HZO. Si Ge induce large local bond distortions have more significant effects on stabilizing the tetragonal phase lowering voltage than Ti Ce. They also do not introduce any midgap states rendering great promise for memory applications.