Aluminum-Copper Bilayers Thin Films Deposited at Room Temperature by RF Magnetron Sputtering

Abstract:

In this work, the effects of room temperature deposition on the structural properties of Al-Cu bilayers thin films were investigated. The bilayers were sputter deposited by RF magnetron sputtering on Si {100} wafers without substrate heating. The thickness of each layer is approximately 500 nm thick. Characterization were performed with grazing incidence X-ray diffraction (XRD) cross-sectional field emission scanning electron microscope (FE-SEM) with chemical analysis by energy dispersive X-ray (EDX) and atomic force microscope (AFM). It was found polycrystalline Al and Cu thin films have been grown with {111} preferred growth orientation with very fine crystallites size (less than 20 nm). The bilayers were in non-strained condition, but each layer shows different morphologies between the columnar and non columnar structure. AFM analysis revealed that the bilayers top surface appears to have higher surface roughness (R_a = 20 nm) due to low adatoms surface mobility during room temperature deposition.

• Periodical: Applied Mechanics and Materials (Volume 606)
• Pages: 105-109
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.606.105
• Online since: August 2014
• Authors: Zulhelmi Alif Abdul Halim, Muhamad Azizi Mat Yajid*, Zulkifli Mohd Rosli, Riyaz Ahmad M. Ali
• Keywords: AFM, FE-SEM, Magnetron Sputtering, XRD

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