[16p-413-1~11] 13.3 Insulator technology

▲ [16p-413-8] MOS interface properties of ALD Al₂O₃/Y₂O₃/GeO_x/Ge gate stacks with plasma post oxidation

〇(D)Mengnan Ke¹, Mitsuru Takenaka¹, Shinichi Takagi¹ (1.Tokyo Univ.)

Keywords:Ge, slow trap density

We propose a new Al₂O₃/Y₂O₃/GeO_x/Ge MOS interface, formed by ALD Al₂O₃/Y₂O₃/Ge MOS structures with plasma post oxidation (PPO) for introducing Y into GeO_x and mitigating slow trapping. Reduction in interface state density (D_it) and slow trap density (DN_st) by PPO are found for Al₂O₃/Y₂O₃/Ge system with PPO. A 1.5-nm-thick Al₂O₃/0.63-nm-thick Y₂O₃/GeO_x/Ge interface can provide a lower amount of DN_st with maintaining similar levels of D_it than the control Al₂O₃/GeO_x/Ge interface.