Structural Study and Electrochemical Deposition of a Copper Layer on n-Si

The reaction and nucleation mechanism of copper (Cu) electrodeposition on a silicon (Si) electrode in an aqueous medium containing 0·01 mol/l copper (II) sulfate (CuSO4) and 0·1 mol/l sodium sulfate (Na2SO4) were investigated using the cyclic voltammetry and chronoamperometry techniques, respectively. The effects of some experimental parameters – namely, copper concentration, pH, scan rate, deposition potential and conditioning surface of the electrode – are described. At the surface of silicon, copper (II) (Cu2+) ions were reduced at −0·8 V against the saturated calomel electrode. It was found that electrodeposition of copper is affected by the rough surface of the n-silicon electrode. The structural and morphological characteristics of the copper layer were studied by using X-ray diffraction and atomic force microscopy. As a result, the new n-silicon/copper structure offers many applications possible in various microelectronic fields.