Deep silicon macropores filled with copper by electrodeposition

Deep macropores in n-type Si have been completely filled with copper (Cu). Homogeneous metal deposition inside the deep pores was achieved by means of electroplating using a solution containing only Cu2SO4 mixed with H2SO4 and no additives. Initial nucleation of the Cu deposition was confined to the bottom of the pores and, by optimizing the filling conditions, uniform filling from the bottom to the top could be achieved. Macropores as deep as 150 mu m with diameters in the 2 mu m range could be filled with Cu, without encountering the so-called "bottleneck" effect. (c) 2006 The Electrochemical Society.