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Abstract The effect of target geometry on coating microstructure and morphology is correlated to changes in deposition conditions, plasma characteristics, and film growth during planar and hollow cathode sputtering. The sputtering plasma properties for the two target geometries were characterized via Langmuir probe analysis as a function of power density and Ar pressure to determine the evolution of ion density for each configuration. Films were then synthesized at the low (0.4 W cm−2) and high (1.2 W cm−2) power densities and characterized using x-ray diffraction, scanning electron microscopy, and electron backscatter diffraction to link changes in texturing, morphology, and microstructure with variations in ion density and sputtering deposition conditions caused by target geometry. It was observed that varying target geometry led to an over threefold increase in deposition rate, homologous temperature, and ion density, which altered the morphology and texture of the film without significant changes to the grain size.
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This content will become publicly available on July 1, 2026
Polycrystalline morphology and anomalous Hall effect in RF-sputtered Co2MnGa films
The Heusler compound Co2MnGa is a topological semimetal with intriguing electronic and magnetic properties, making it a promising candidate for spintronic applications. This study systematically investigates the effects of substrate temperature and radio frequency (RF) sputtering power on the structure, morphology, and anomalous Hall effect (AHE) in Co2MnGa thin films with the goal to uncover trends in growth–morphology–property relationships. Using x-ray diffraction line analysis, we identify variations in film orientation and crystallinity, revealing the emergence of high-index textures at specific growth conditions. Atomic force microscopy imaging provides insight into grain morphology and size distributions demonstrating a correlation between deposition parameters and film texture. Magnetotransport measurements show a strong dependence of AHE on growth conditions, exhibiting a nonmonotonic relationship with RF power and temperature. Despite significant variations in microstructure, a striking linear relationship between AHE and the zero-field slope of the Hall resistivity is observed, suggesting an underlying universal mechanism. These findings provide a foundation for investigating the complex interplay of Co2MnGa informing us broadly that the AHE is strongly tunable by morphology, while at the same time the critical field remains robust.
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- Award ID(s):
- 2328747
- PAR ID:
- 10612117
- Publisher / Repository:
- Journal of Vacuum Science and Technology A
- Date Published:
- Journal Name:
- Journal of Vacuum Science & Technology A
- Volume:
- 43
- Issue:
- 4
- ISSN:
- 0734-2101
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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