Pore filling of macropores prepared in p‐type silicon by copper deposition

Abstract

PACS 68.37.Hk, 81.07.Bc, 82.45.Vp Copper deposition into ordered macroporous silicon prepared in p-type substrates was investigated by immersion plating and electrochemical deposition in an aqueous solution containing Cu 2+ ions. When the sample was immersed in 0.1 M CuSO 4 solution at the open circuit potential, Cu crystallites are clearly observed at the top surface and inside the pores. The deposition of Cu oxidizes the substrate simultaneously to SiO 2 . On the other hand, the potentiostatic deposition in the dark revealed that Cu deposits preferentially at the pore bottom and propagates towards the top surface. Furthermore, when the substrate was illuminated under cathodic potential, the Cu deposition was enhanced mainly at the top-surface and around the pore walls. The different deposition behavior was compared and discussed.

Silicon Porosification: State of the Art

“…Ogata and coworkers 569,575,576 reported that shapes of deposits could be controlled as rods or tubes in ordered macroporous p-type silicon (see Figure 94). They have shown that the mechanism of the macropore filling depends on various factors, for instance, the equilibrium potential of metal, the depth of the macropore, the supporting electrolyte for electrodeposition and the displacement deposition.…”

Filling of mesoporous silicon with copper by electrodeposition from an aqueous solution

“…From a different point of view, there are possibilities to form various morphologies of deposits by controlling the electrodeposition reaction on the pore wall. We reported that shapes of deposits could be controlled as rods or tubes in ordered macroporous p-type silicon [13][14][15][16]. The mechanism of the macropore filling depends on various factors, for instance, the equilibrium potential of metal, the depth of the macropore, the supporting electrolyte for electrodeposition and the displacement deposition.…”

“…A limited number of studies on the filling of porous silicon with metals by electrodeposition were reported [7][8][9][10][11][12][13][14][15][16] compared with the other non-conducting template such as porous alumina and porous silica. This is because electrodeposition reactions proceed not only at the pore bottom but also on the wall, leading to the complex distribution of electric field and concentration profiles in the pore.…”

Impregnation of porous silicon with conducting polymers

“…It is an experimental fact that the applied current density and the type of anodizing solution determine the produced pore size and morphology [2,12]. Figure 1 shows the SEM image of crosssectional (image a) and top (inset: image b) views of the porous layer produced on a heavily doped substrate under the above mentioned conditions.…”