title: Utilizing pulsed laser deposition lateral inhomogeneity as a tool in combinatorial material science.
abstract: Pulsed laser deposition (PLD) is widely used in combinatorial material science, as it enables rapid fabrication of different composite materials. Nevertheless, this method was usually limited to small substrates, since PLD deposition on large substrate areas results in severe lateral inhomogeneity. A few technical solutions for this problem have been suggested, including the use of different designs of masks, which were meant to prevent inhomogeneity in the thickness, density, and oxidation state of a layer, while only the composition is allowed to be changed. In this study, a possible way to take advantage of the large scale deposition inhomogeneity is demonstrated, choosing an iron oxide PLD-deposited library with continuous compositional spread (CCS) as a model system. An Fe₂O₃-Nb₂O₅ library was fabricated using PLD, without any mask between the targets and the substrate. The library was measured using high-throughput scanners for electrical, structural, and optical properties. A decrease in electrical resistivity that is several orders of magnitude lower than pure α-Fe₂O₃ was achieved at ∼20% Nb-O (measured at 47 and 267 °C) but only at points that are distanced from the center of the PLD plasma plume. Using hierarchical clustering analysis, we show that the PLD inhomogeneity can be used as an additional degree of freedom, helping, in this case, to achieve iron oxide with much lower resistivity.
authors: David A
authors: DA
authors: Keller
authors: Adam
authors: A
authors: Ginsburg
authors: Hannah-Noa
authors: HN
authors: Barad
authors: Klimentiy
authors: K
authors: Shimanovich
authors: Yaniv
authors: Y
authors: Bouhadana
authors: Eli
authors: E
authors: Rosh-Hodesh
authors: §Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States.
authors: Ichiro
authors: I
authors: Takeuchi
authors: Hagit
authors: H
authors: Aviv
authors: Yaakov R
authors: YR
authors: Tischler
authors: Assaf Y
authors: AY
authors: Anderson
authors: Arie
authors: A
authors: Zaban
mesh_terms: D020650:Combinatorial Chemistry Techniques; D058085:Iron Compounds / Q000737:chemistry*; D007834:Lasers; D008422:Materials Testing / Q000295:instrumentation* / Q000379:methods; D054852:Small Molecule Libraries
chemical_list: D058085:Iron Compounds; D054852:Small Molecule Libraries
keywords: all-oxide photovolatics; combinatorial material science; continuous compositional spread (CCS); hematite (α-Fe2O3); hierarchical clustering; pulsed laser deposition (PLD); thin films