EPROM silicon chip. Coloured scanning electron micrograph (SEM) of the surface architecture of part of an EPROM (Eraseable Programmable Read- Only Memory) silicon microchip. The narrow tracks (coloured) that have been deposited on the substrate (blue) form part of the chip's micro- circuitry. The pits in the tracks are connection points, where connections are made to circuit elements on the other side of the substrate. Image of an AMD AM27C512- 155DC chip. Magnification: x420 at 4x11cm size. x920 at 10x3.5"~PANORAMA"