Mechanical properties of atomic layer deposition-reinforced nanoparticle thin films

Abstract

Nanoparticle thin films (NTFs) exhibit multifunctionality, making them useful for numerous advanced applications including energy storage and conversion, biosensing and photonics. Poor mechanical reliability and durability of NTFs, however, limit their industrial and commercial applications. Atomic layer deposition (ALD) represents a unique opportunity to enhance the mechanical properties of NTFs at a relatively low temperature without drastically changing their original structure and functionality. In this work, we study how ALD of different materials, Al(2)O(3), TiO(2), and SiO(2), affects the mechanical properties of TiO(2) and SiO(2) NTFs. Our results demonstrate that the mechanical properties of ALD-reinforced NTFs are dominantly influenced by the mechanical properties of the ALD materials rather than by the compositional matching between ALD and nanoparticle materials. Among the three ALD materials, Al(2)O(3) ALD provides the best enhancement in the modulus and hardness of the NTFs. Interestingly, Al(2)O(3) ALD is able to enhance not only the modulus and hardness but also the toughness of NTFs. Our study presents an additional benefit of depositing nanometer scale ALD layers in NTFs; that is, we find that the hardness and modulus of ultrathin ALD layers (<5 nm) can be estimated from the mechanical properties of ALD-reinforced NTFs using a simple mixing rule. This investigation also provides insight into the use of nanoindentation for testing the mechanical properties of ultrathin ALD-reinforced NTFs.

Reinforcing nanocolloidal crystals by tuning interparticle bonding via atomic layer deposition

“…(5a) and (5b) to determine H NC . Through this fitting, we find that H NC = 4.8 GPa and H NC = 4.3 GPa for 289 nm and 254 nm NCCs, respectively, which match each other well and also match the values reported in the literature for amorphous SiO 2 [27,62]. Fig.…”

“…(5c) matches the experimental modulus very well, again validating the particulate composite model for regime III. Here, based on the fitting, E ALD = 135 GPa and E NC = 40 GPa, matching the values reported in the literature for Al 2 O 3 ALD [51,52] and amorphous SiO 2 coatings [27,63].…”

“…Thus, ALD has been used as a way of infiltrating NCC templates to generate inverse opals [19][20][21][22][23][24][25][26]. Our previous studies [27,28] demonstrated that ALD can be used to significantly reinforce films composed of randomly packed polydisperse nanoparticles. However, the mechanical behavior of ALD-treated NCCs composed of a regular array of monodisperse nanocolloids has not been previously studied.…”

Atomic layer deposition of alumina on γ‐Al2O3 nanofibres

“…ALD is found to be suitable for conformal growth of thin solid films, such as TiO 2 , SiO 2 and Al 2 O 3 , over a variety of substrates and is also suited to the mechanical reinforcement of e.g . some oxide nanoparticles . Therefore, ALD can be applied for the treatment of high aspect ratio objects .…”

Comparison of the physicochemical properties of Al2O3 layers applied to the surfaces of cpTi and the Ti6Al7Nb alloy using the ALD method

“…To deposit an Al 2 O 3 layer using ALD, trimethylaluminum (TMA) and water vapor are sequentially pulsed through the reaction chamber. 13 The number of cycles was 830, which made obtaining a layer thickness of about 120 nm possible. Layers of this thickness are commonly used in the surface modification of metallic biomaterials in contact with bone tissue.…”