Nanocrystalline Electroplated Cu–Ni: Metallic Thin Films with Enhanced Mechanical Properties and Tunable Magnetic Behavior
- 22 March 2010
- journal article
- research article
- Published by Wiley in Advanced Functional Materials
- Vol. 20 (6) , 983-991
Abstract
Nanocrystalline 3 µm thick Cu1–xNix (0.45 ≤ x ≤ 0.87) films are electrodeposited galvanostatically onto Cu/Ti/Si (100) substrates, from a citrate‐ and sulphate‐based bath containing sodium lauryl sulphate and saccharine as additives. The films exhibit large values of reduced Young's modulus (173 < Er < 192 GPa) and hardness (6.4 < H < 8.2 GPa), both of which can be tailored by varying the alloy composition. The outstanding mechanical properties of these metallic films can be ascribed to their nanocrystalline nature—as evidenced by X‐ray diffraction, transmission electron microscopy, and atomic force microscopy—along with the occurrence of stacking faults and the concomitant formation of intragranular nanotwins during film growth. Due to their nanocrystalline character, these films also show very low surface roughness (root mean square deviation of around 2 nm). Furthermore, tunable magnetic properties, including a transition from paramagnetic to ferromagnetic behavior, are observed when the Ni percentage is increased. This combination of properties, together with the simplicity of the fabrication method, makes this system attractive for widespread technological applications, including hard metallic coatings or magnetic micro/nano‐electromechanical devices.Keywords
This publication has 59 references indexed in Scilit:
- Tailoring the microstructure and surface morphology of metal thin films for nano-electro-mechanical systems applicationsNanotechnology, 2008
- Saccharin Effects on Direct-Current Electroplating Nanocrystalline Ni–Cu AlloysJournal of the Electrochemical Society, 2008
- Toward a quantitative understanding of mechanical behavior of nanocrystalline metalsActa Materialia, 2007
- Power consumption reduction scheme of magnetic microactuation using electroplated Cu–Ni nanocompositeApplied Physics Letters, 2007
- Synthesis and characterization of nickel tungsten alloys by electrodepositionElectrochimica Acta, 2005
- Determination of Young's modulus of electroplated nickelElectrochimica Acta, 2003
- Electrodeposition and Characterization of Nickel-Copper Alloy Films as Electrode Material in Alkaline MediaJournal of the Electrochemical Society, 2002
- Oxidation, Diffusion and Segregation in CuNi(Mn) Films Studied by AESMicrochimica Acta, 2000
- An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experimentsJournal of Materials Research, 1992
- The critical concentration for the onset of ferromagnetism in CuNi alloysJournal of Physics F: Metal Physics, 1977