Roughness of the porous silicon dissolution interface

摘要: We present a study of the fluctuations in dissolution front observed during formation porous silicon, leading finally to layer thickness inhomogeneities. Two types were revealed, one at millimeter scale (waviness) and other micrometer (roughness). Root mean square amplitudes are comparable. In both cases velocity can be invoked we discuss their dependence on current density viscosity solution. The large attributed planar resistivity wafer. second type fluctuation displays typical spatial periodicity comparable wavelength light so that statistical characterization performed by optical measurements. Davies–Bennett model quantitatively describes induced scattering. Remarkably, these increase linearly with up critical value where saturation regime is observed. order explain this behavior, show importance initial surface state wafer medium.