Figure 4From: Highly flexible method for the fabrication of photonic crystal slabs based on the selective formation of porous siliconScanning electron microscope images of three different samples. (a) Structure with a lattice parameter of 3 μm due to the proton beam line spacing was set to 3 μm. (b) Same structure with a lattice parameter of 2 μm. (c) The photonic slab presents a period of 1.5 μm.Back to article page