Palladium-free electroless deposition of pure copper film on glass substrate using hydrazine as reducing agent

Thin copper films were fabricated on glass substrates by palladium-free electroless deposition, using hydrazine. The effects of modifying the deposition parameters like temperature, initial concentration and pH of electroless bath on the deposition rate and morphology of resulting films were studied and optimized. The film deposition is performed in two simple steps which shortens the pretreatment time and avoids applying expensive components and is environmentally benign. FESEM images show a uniform dispersion of Cu nanoparticles on the glass substrates in the first step. These nanoparticles act as an activator in the growth of homogeneous Cu thin film in the second step. The activation energy for the growth of Cu films was found to be 62 kJ/mol. EDX and XRD analysis demonstrates that the composition of the deposits was pure Cu with FCC crystal structure. The Cu films of 260 nm thickness showed a resistivity of about 2 × 10−6 Ω cm.