Area-Selective Atomic Layer Deposition of Metal Oxides on Noble Metals through Catalytic Oxygen Activation

Abstract

Area-selective atomic layer deposition (ALD) is envisioned to play a key role in next-generation semiconductor processing and can also provide new opportunities in the field of catalysis. In this work, we developed an approach for the area-selective deposition of metal oxides on noble metals. Using O2 gas as co-reactant, area-selective ALD has been achieved by relying on the catalytic dissociation of the oxygen molecules on the noble metal surface, while no deposition takes place on inert surfaces that do not dissociate oxygen (i.e., SiO2, Al2O3, Au). The process is demonstrated for selective deposition of iron oxide and nickel oxide on platinum and iridium substrates. Characterization by in situ spectroscopic ellipsometry, transmission electron microscopy, scanning Auger electron spectroscopy, and X-ray photoelectron spectroscopy confirms a very high degree of selectivity, with a constant ALD growth rate on the catalytic metal substrates and no deposition on inert substrates, even after 300 ALD cycles. We demonstrate the area-selective ALD approach on planar and patterned substrates and use it to prepare Pt/Fe2O3 core/shell nanoparticles. Finally, the approach is proposed to be extendable beyond the materials presented here, specifically to other metal oxide ALD processes for which the precursor requires a strong oxidizing agent for growth.

Scalable neutral H2O2 electrosynthesis by platinum diphosphide nanocrystals by regulating oxygen reduction reaction pathways

“…Ultrathin metal oxides by ALD have been applied to encapsulate the supported nanoparticles and improve the size stability of nanoparticle catalysts 35,36 . In order to minimize additional electrocatalytic effects from ALD overcoating layer, we chose the relatively inert Al 2 O 3 rather than the typical transition metal oxide promotors (e.g., Co 3 O 4 37 , MnO 38 , Fe 2 O 3 39 , and MoO 3 40 ). ALD of a thin Al 2 O 3 layer was carried out to stabilize the ultrasmall PtP 2 NCs on a commercial carbon support by alternately exposing the sample to cycles of trimethylaluminum (TMA) and water at 175°C (Fig.…”

The Influence of Ozone: Superstoichiometric Oxygen in Atomic Layer Deposition of Fe2O3 Using tert‐Butylferrocene and O3

“…Second, the oxygen uptake phenomenon may be related to that of a recent report of Fe 2 O 3 ALD on Pt surfaces where it was hypothesized that oxygen was transported through the film. [ 68 ] In the study by Singh et al, it was observed that when performed on platinum substrates, iron oxide ALD could be achieved using tert ‐butylferrocene and molecular oxygen gas, obviating the need for ozone. While O 2 was not reactive enough to react with the iron precursor at moderate temperatures, it was hypothesized that the oxygen species were able to migrate through the film to the underlying platinum substrate where it was dissociated into reactive oxygen atoms to participate in the ALD reactions.…”

Surface functionalization on nanoparticles via atomic layer deposition

“…Pt could selectively initiate its growth on Pd to form a core-shell structure exclusively (shown in Fig. 4a) [58][59][60].…”