Fig. 4From: Chemical Composition of Nanoporous Layer Formed by Electrochemical Etching of p-Type GaAsSEM and CL micrographs taken from the top surface (a, b) and cross section (c, d) of porous p-GaAs with 20 keV at room temperature formed in 49 % HF solution at 2 mA/cm2 Back to article page