In this Letter, the robust ferroelectric properties of low-temperature (350 °C) Hf0.5Zr0.5O2 (HZO) films are investigated. We demonstrate that the lower crystallization temperature of HZO films originates from a densified film deposition with an anhydrous H2O2 oxidant in the atomic layer deposition process. As a consequence of this densification, H2O2-based HZO films showed completely crystallinity with fewer defects at a lower annealing temperature of 350 °C. This reduction in the crystallization temperature additionally suppresses the oxidation of TiN electrodes, thereby improving device reliability. The low-temperature crystallization process produces an H2O2-based HZO capacitor with a high remanent polarization ( Pr), reduced leakage current, high breakdown voltage, and better endurance. Furthermore, while an O3-based HZO capacitor requires wake-up cycling to achieve stable Pr, the H2O2-based HZO capacitor demonstrates a significantly reduced wake-up nature. Anhydrous H2O2 oxidant enables the fabrication of a more reliable ferroelectric HZO device using a low process thermal budget (350 °C).

Aluminum nitride (AlN) thin films were grown using thermal atomic layer deposition in the temperature range of 175–350 °C. The thin films were deposited using trimethyl aluminum (TMA) and hydrazine (N2H4) as a metal precursor and nitrogen source, respectively. Highly reactive N2H4, compared to its conventionally used counterpart, ammonia (NH3), provides a higher growth per cycle (GPC), which is approximately 2.3 times higher at a deposition temperature of 300 °C and, also exhibits a low impurity concentration in as-deposited films. Low temperature AlN films deposited at 225 °C with a capping layer had an Al to N composition ratio of 1:1.1, a close to ideal composition ratio, with a low oxygen content (7.5%) while exhibiting a GPC of 0.16 nm/cycle. We suggest that N2H4 as a replacement for NH3 is a good alternative due to its stringent thermal budget.

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In recent times, the requirements have become extremely stringent for employing silicon nitride (SiN x ) films in various types of applications. For instance, high etch resistance coating is required for a film to act as an etch stop layer and gate spacer for nanoscale patterning for next-generation semiconductor devices. In this study, a chlorodisilane precursor, 1,1,1-trichlorodisilane (3CDS, Si 2 H 3 Cl 3 ), was used to deposit SiN x films using a hollow cathode plasma-enhanced atomic layer deposition system and compared with the SiN x films deposited using hexachlorodisilane (HCDS, Si 2 Cl 6 ) as well as pentachlorodisilane (PCDS, Si 2 HCl 5 ). In the process temperature range of 310−435 °C, a self-limiting surface reaction behavior with 4 × 10 3 L of 3CDS exposure and 2 × 10 6 L of NH 3 plasma exposure was observed. 3CDS particularly gives ∼45 and ∼20% higher growth per cycle than HCDS and PCDS, respectively. In addition, the SiN x films deposited using 3CDS at 480 °C have improved the wet etch rate (0.4 nm/min in 200:1 HF) and density (2.88 g/cm 3 ). Analyzed with time-of-flight secondary ion mass spectrometry, the 3CDS-derived SiN x films contain less hydrogen than the SiN x films formed using HCDS under identical process conditions. These superior film properties can be attributed to the unique structural characteristics of 3CDS, where the three chlorine and three hydrogen atoms are localized on each of the two silicon atoms. The SiN x films deposited on nanotrenches with a high aspect ratio (6:1) at 390 and 480 °C showed >85% and >65% conformality, respectively, and high etch resistance (1.9 and 0.8 nm/min, respectively, in 200:1 HF), suggesting that high-quality SiN x films can be formed from 3CDS on both planar and patterned surfaces.

Herein, we investigated the chemical reactions associated with low-energy electron exposures on an inorganic-organic hybrid thin film system deposited using molecular atomic layer deposition (MALD) for EUV photoresist applications. Using the hybrid thin films consisting of trimethylaluminum (TMA) and hydroquinone (HQ), we determined the critical doses and thickness contrast of the hybrid materials at various electron energies (up to 400 eV). The custom-built in-situ Fourier-Transform Infrared (FTIR) spectroscopy system, equipped with an electron flood gun and gas residual analyzer (RGA), was employed to monitor the chemical changes induced by low-energy electrons in the hybrid thin films. Based on the in-situ FTIR and RGA results, potential chemical reaction mechanisms responsible for the change in solubility of the TMA/HQ material are proposed.