A silicon substrate has area-selectively formed porous silicon in which porosity, pore size, and pore size distribution of a porous silicon region and a shape of the porous silicon are controlled. The twist pin includes a bulge which establishes compressive contact force with a sidewall of a via in which the twist pin resides, and the resulting force resists movement of the end of the twist pin away from the electronic component to assure good signal conductivity. The deck can slidably support the holder from a first location to an item loading location. The system can still further have a detector for receiving optical response from the scanning assembly and a data processing system. Also disclosed are processes performed in a device for generating metadata for programming events.