Effects of a Ni alloying element on Al-Ni metallization

• Published in: Semiconductor science and technology Vol. 27; no. 1; pp. 15021 - 15026
• Main Authors: Lee, K W, Han, D M, Jeong, K H, Lee, K B, Lee, J G, Jeong, C O, Bae, Y H, Ruh, H, Kim, C S, Lee, E G
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 11.01.2012; Institute of Physics
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electrical properties of specific thin films; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; metallization; Metals and metallic alloys; Ni alloy; Physics; Grain size; High strain; Annealing; Aluminium base alloys; Electrical conductivity; Nickel alloys; Metallizing; Elastic deformation; Texture; Thin films; Arrhenius equation; Property structure relationship; Supersaturated solid solution
• ISSN: 0268-1242; 1361-6641
• DOI: 10.1088/0268-1242/27/1/015021

The effect of the Ni content (2-18 at.% Ni) in Al thin films on their resistivity, hillock formation and Al3Ni compound formation was investigated. The as-deposited Al-Ni-alloy films showed high elastic strains which increased with increasing Ni content. In addition, the annealing of the supersaturated Al-Ni-alloy thin films yielded two phases: Al3Ni and Al with strong (2 2 0) and (1 1 1) textures, respectively, suggesting that the nucleation of (2 2 0) Al3Ni is closely associated with (1 1 1) Al. The resistivity of the as-annealed Al-Ni-alloy films varied as functions of the volume fraction and grain size of the two phases, which were determined by the Ni content and annealing temperature, respectively. The hillock formation was effectively suppressed when a small amount of Ni was added to the Al alloy. The results showed that a Ni content of less than approximately 4.5 at.% produced hillock-free Al-alloy thin films with a low resistivity of less than 6.0 µΩ cm upon annealing at 350 °C.