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In this work, a novel chlorodisilane precursor, pentachlorodisilane (PCDS, HSi2Cl5), was investigated for the growth of silicon nitride (SiNx) via hollow cathode plasma-enhanced atomic layer deposition (PEALD). A well-defined self-limiting growth behavior was successfully demonstrated over the growth temperature range of 270–360 °C. At identical process conditions, PCDS not only demonstrated approximately >20% higher growth per cycle than that of a commercially available chlorodisilane precursor, hexachlorodisilane (Si2Cl6), but also delivered a better or at least comparable film quality determined by characterizing the refractive index, wet etch rate, and density of the films. The composition of the SiNxfilms grown at 360 °C using PCDS, as determined by X-ray photoelectron spectroscopy, showed low O content (∼2 at. %) and Cl content (<1 at. %; below the detection limit). Fourier transform infrared spectroscopy spectra suggested that N–H bonds were the dominant hydrogen-containing bonds in the SiNxfilms without a significant amount of Si–H bonds originating from the precursor molecules. The possible surface reaction pathways of the PEALD SiNxusing PCDS on the surface terminated with amine groups (−NH2and −NH−) are proposed. The PEALD SiNxfilms grown using PCDS also exhibited a leakage current density as low as 1–2 nA/cm2at 2 MV/cm and a breakdown electric field as high as ∼12 MV/cm.

Increasing interest in the development of alternative energy storage technologies has led to efforts being taken to improve the energy density of dielectric capacitors with high power density. However, dielectric polymer materials still have low energy densities because of their low dielectric constant, whereas Pb-based materials are limited by environmental issues and regulations. Here, the energy storage behaviors of atomic layer-deposited Hf1–XZrXO2(X= 0–1) thin films (10 nm) and the phase transformation mechanism associated with an enhancement of their energy density are reported using unipolar pulse measurements. Based on electrical and material characterization, the energy density and energy efficiency are dependent on the Zr content, and stress-induced crystallization by the encapsulating Hf1–XZrXO2films with TiN top electrodes prior to annealing can enhance the energy density (up to 47 J/cm3at a small voltage value of 3.5 MV/cm) while minimizing energy loss even at low process temperatures (400 °C). This work will facilitate the realization of Hf1–XZrXO2-based capacitors for lead-free electrostatic energy storage applications.