Investigation of the oxidation behaviour of thin film and bulk copper

http://ntur.lib.ntu.edu.tw/bitstream/246246/92346/1/04.pdf

Effects of additives and chelating agents on electroless copper plating

Cu, Co and Ni thin films and Co-Ni-Cu/Cu multilayers have been electrodeposited directly on n-type silicon substrates. This removes the need of using a seed-layer deposited by some other methods as a part of the growth process and integrates an efficient, inexpensive and convenient method for fabricating thin films with silicon technology. The deposits were prepared under potentiostatic conditions from different aqueous solutions, containing basically: (i) sulphates of the metallic ions plus sodium sulphate and boric acid for thin films and (ii) Ni sulphamate, Co sulphate, Cu sulphate, boric acid and sulphamic acid for multilayers. Aspects related to the deposition process and deposited layers were investigated by cyclic voltammetry, current transients, scanning electron microscopy. Rutherford backscattering and magnetoresistance measurements. Typically, thin compact metallic layers with regular granularity were obtained. Depending on the additives used, different nucleation and growth mechanisms were obseived. Magnetic multilayers with a maximum giant magnetoresistive (GMR) ratio of about 10% were produced.

Electrodeposition of thin films and multilayers on silicon

The electrodeposition of thin films of the clement cobalt on silicon wafers opens the possibility of producing magnetic structures on top of a technological substrate using an efficient and inexpensive method. In this paper, we present an extensive study of the electrodeposition of Co on Si(100) n-type substrates. Co thin films with metallic appearance and uniform thickness were obtained at deposition rates of 0.6 (2.8) nm/s for the 26 (104) mM Co electrolyte. A strong dependence of the surface roughness on the nucleation mechanism. i.e., instantaneous or progressive, was observed for layer thicknesses below 300 nm. Simultaneous magneto-optical Kerr effect and magnetoresistance measurements showed that magnetic behavior depends on the nucleation mechanism as well. Coercivity decays with increasing thickness, t, following a power law of the type t n , with n = 1.6 (2.1) for the 26 (104) mM electrolyte, which reflects a strong dependence of the magnetic behavior on surface effects. A large variation of the in-plane coercive fields was observed for the 104 mM electrolyte, which varied from 730 to 13 Oe as film thickness increased from 26 to 260 nm.

https://iopscience.iop.org/article/10.1149/1.1468646/pdf

Morphology and Magnetic Properties of Co Thin Films Electrodeposited on Si

The paper reports the use of self-assembled monolayers (SAMs) of dithiols to induce electroless copper deposition on a gold substrate. The metallization catalyst, palladium nanoparticles, is bound on the dithiol SAM. The assembly process is followed by IR and X-ray photoelectron spectroscopies to confirm the formation of a monolayer with bound catalyst. Electroless metallization is then carried out with a steady deposition rate of 130 nm/min. Additionally, microcontact printing of the catalyst on the SAM by poly(dimethylsiloxane) stamps is used to localize copper deposits. Resulting metallization is selective and allows for a high resolution.

J. Barrett

Papers

Electroless copper metallisation of titanium nitride

Selective electroless copper metallization on a titanium nitride barrier layer