Published online by Cambridge University Press: 15 February 2011
The fine structure of porous silicon (PS) plated electro-chemically with indium at a low plating charge of 0.03 C/cm2 has been studied mainly using Rutherford backscattering spectrometry and a transmission electron microscope. The results obtained here show (1) that the amount of plated In atoms strongly depends on the oxidation states of the pore surfaces, (2) that the average In densities, the maximum of which is usually located near the PS - Si substrate interface, are typically larger than 1 % of the Si densities in the PS layers, and (3) that the plated In atoms are concentrated locally in pores larger in size. Two-step thermal oxidation of an In-plated PS specimen results in a structure of nm-sized Si crystallites surrounded mainly by Si oxide and In oxide.