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The present study reports the impact of process conditions and post annealing treatment on the stress and physico-chemical properties in different types of plasma enhanced atomic layer deposited (PEALD) SiNx films. More specifically, the SiNx films deposited at 500 °C were annealed subsequently at 1000 °C in N2 ambient for different times ranging between 30 and 6750 s and were subjected to thickness, mass, refractive index, chemical bonds and structure, H content, N/Si stoichiometry, morphology, roughness, and uniformity monitoring. Depending on the deposition process conditions, we confirm the possibility to form, at 500 °C with PEALD, some very compressive SiN films with reduced hydrogen content by controlling the plasma conditions along the deposition process. More interestingly, these compressive films with low hydrogen concentration exhibit high thermo-mechanical stability compared to hydrogenated PEALD and plasma enhanced chemical vapor deposition silicon nitride from this study or reported in the literature, films which typically tend to become tensile with a similar annealing sequence. These results confirm the importance of the plasma power to engineer the as-deposited silicon nitride stress but also highlight the role of hydrogen in the thermal instability of these layers, a low H concentration being needed for a better mechanical stability. [ABSTRACT FROM AUTHOR]

In this study, we explored the key properties and functionalities of plasma enhanced atomic layer deposition (PEALD) SiNx films, synthesized using different deposition temperatures (500–550 °C) and plasma conditions (lower and higher), both on 300 mm blanket Si and on several integrated 3D topology substrates, at the thicknesses relevant for diverse nanoscale applications. Our study shows that with an increase of temperature (500–550 °C), a small reduction in HF wet etch rate (1.1–0.69 nm/min), and H content (9.6% vs 7.4%) was observed. When using higher plasmas, significant improvements in blanket properties were observed. The films were denser (2.95 g/cm3), exhibited lower H content (2.4%), showed better etch rates (0.39 and 0.44 nm/s for HF and CF4 based), and SiNx grew without any nucleation delay on alternative Si1−xGex channel surfaces. The vertical and lateral conformality was found to be similar and appears not to be impacted with the plasma conditions. Extensive steam oxidation barrier studies performed at the sidewalls of different aspect ratio lines showed the PEALD SiNx liner scaling potentiality down to 1 nm when deposited using higher plasma. In addition, the outer gate and inner spacer properties were found to be superior (with lower loses) for higher plasma films when subjected to several dry etch, strips, and H3PO4 chemistries. The outstanding conformality (90%–95% on aspect ratios ≤10:1) combined with excellent high end material properties in the ultrathin regimes (1–10 nm) corroborate the virtue of PEALD SiNx toward integration in scaled down and advanced nanoelectronics device manufacturing. [ABSTRACT FROM AUTHOR]

An attempt has been made to utilize uniquely high electron mobility of graphene on hexagonal boron nitride (h-BN) to electron emitter. The field emission property of graphene/h-BN/Si structure has shown enhanced threshold voltage and emission current, both of which are key to develop novel vacuum nanoelectronics devices. The field emission property was discussed along with the electronic structure of graphene investigated by Fowler-Nordheim plot and ultraviolet photoelectron spectroscopy. The result suggested that transferring graphene on h-BN modified its work function, which changed field emission mechanism. Our report opens up a possibility of graphene-based vacuum nanoelectronics devices with tuned work function. [ABSTRACT FROM AUTHOR]