Molecular sieves assisted chemical vapor deposition preparation of high-κ dielectric m-ZrO2 nanosheets

Abstract

Abstract In order to address challenges posed by the reduction in transistor size, researchers are concentrating on two-dimensional (2D) materials with high dielectric constants and large band gaps. Monoclinic ZrO 2 (m-ZrO 2 ) has emerged as a promising gate dielectric material due to its suitable dielectric constant, wide band gap, ideal valence-band offset, and good thermodynamic stability. However, current deposition methods face compatibility issues with 2D semiconductors, highlighting the need for high-quality dielectrics and interfaces. Here, high-quality 2D m-ZrO 2 single crystals are successfully prepared using a one-step chemical vapor deposition (CVD) method, aided by 5A molecular sieves for oxygen supply. The prepared ZrO 2 is utilized as a gate dielectric in the construction of MoS 2 field-effect transistors (FETs) to investigate its electrical property. The FETs exhibit a high carrier mobility of up to 5.50 cm 2 ·V −1 ·s −1 , and a current switching ratio ( I on/off ) of approximately 10 4 , which aligns with the current standards of logic circuits, indicating that ZrO 2 has application value as a gate dielectric. The successful one-step preparation of single-crystal ZrO 2 paves the way for the utilization of high- κ gate dielectrics and creates favorable conditions for the development of high-performance semiconductor devices, offering new possibilities for transistor miniaturization.