Enhancing chemisorption efficiency and thin-film characteristics via a discrete feeding method in high-k dielectric atomic layer deposition for preventing interfacial layer formation

Abstract

Interfacial layer formation between electrodes and insulators is a well-known issue in metal–insulator–metal capacitors and can severely limit their electrical properties. In this study, we investigate the use of the discrete feeding method (DFM) in atomic layer deposition (ALD) to prevent the degradation of electrical properties caused by the interfacial layer. Our results show that the DFM can significantly improve the chemisorption efficiency of precursors, increase the growth rate, and reduce deposition time in ALD. Furthermore, we demonstrate that the thin-film characteristics can be improved through dense chemisorption of precursors. By applying the DFM to the deposition of ZrO₂, which is commonly used as an insulator in dynamic random-access memory capacitors, we show that interfacial layer formation can be prevented. We confirm the effectiveness of the DFM by comparing the effects of different precursor sizes, analyzing the chemical states of Zr and Ti, and performing AC non-linearity and equivalent oxide thickness analyses. These findings provide new insights into the origin and solution of interfacial layer formation in metal–insulator–metal capacitors and have important implications for the development of electronic devices.