Controllable Oxidation of ZrS<sub>2</sub> to Prepare High‐κ, Single‐Crystal m‐ZrO<sub>2</sub> for 2D Electronics
Yuanyuan Jin, Jian Sun, Ling Zhang, Junqiang Yang, Yangwu Wu, Bingying You, Xiao Liu, Kai Leng, Song Liu
Abstract
Abstract High‐κ materials that exhibit large permittivity and band gaps are needed as gate dielectrics to enhance capacitance and prevent leakage current in downsized technology nodes. Among these, monoclinic ZrO 2 (m‐ZrO 2 ) shows good potential because of its inertness and high‐κ with respect to SiO 2 , but a method to produce ultrathin single crystal is lacking. Here, the controllable preparation of ultrathin m‐ZrO 2 single crystals via the in situ thermal oxidation of ZrS 2 is achieved. As‐grown m‐ZrO 2 presents an equivalent oxide thickness of ≈0.29 nm, a high dielectric constant of ≈19, and a breakdown voltage ( E BD ) of ≈7.22 MV cm −1 . MoS 2 field effect transistor (FET) by using m‐ZrO 2 as a dielectric layer shows comparable mobility to that using SiO 2 dielectric. The ultraclean interface of m‐ZrO 2 /MoS 2 and high crystalline quality of m‐ZrO 2 lead to negligible hysteresis in transfer curves. Single crystal m‐ZrO 2 dielectric shows potential application in digital complementary metal oxidesemiconductor (CMOS) logic FET.