The first stage in the manufacture of a silicon chip (integrated circuit). A small crystal seed" of silicon is suspended in molten polysilicon, contained in a graphite crucible and heated by a graphite element. The seed is rotated in the melt and slowly withdrawn to grow a larger, cylindrical crystal of silicon. The eventual cylindrical mass may be 75-100 millimeters (mm) in diameter and up to 1 metre long. After polishing & grinding to exact dimensions, individual wafers of between 0.25 and 0.5mm thickness are sliced from the block. Crystalline silicon wafers form the bases for the ultimate integrated circuits."