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The morphology, texture evolution and growth behavior of the meta-stable NiSn3 intermetallic compound (IMC) in Sn electrodeposits over Ni were investigated. It was found that at lower storage temperatures (<; 100°C), the plate-like NiSn3 is the dominant IMC phase in the Sn layers. Upon raising the temperature, a competition between the initiations of NiSn3 and Ni3Sn4 phases was observed as identified by energy dispersive X-ray. The crystal structure of NiSn3 was determined by the powder diffraction pattern. The investigations revealed that the growth rate of NiSn3 in terms of the penetration depth from the Sn/Ni interface to the Sn surface follows the square-root power law, implying a diffusion controlled phase growth. The diffusion coefficients of the NiSn3 phase growth were determined at different temperatures (25°C, 50°C, and 75°C), which are significantly higher than that reported for Ni3Sn4 under the same temperatures. The activation energy for the growth of NiSn3 obtained is 39.90 kJ/mol. Hardness and Young's modulus of NiSn3 were determined by means of nanoindentation. This paper discusses the potential influences of the NiSn3 phase growth on the reliability of electronic components containing Ni-Sn diffusion couple.