Most semiconductor devices are made on silicon, and the starter substrate for any circuit is a silicon wafer, typically 6, 8 or 12 inch in diameter. Wafers are sliced from large single-crystal silicon ingots and polished to extreme tolerances. The ingots, are usually made using a method called CZ (short for its inventor, the Polish scientist Jan Czochralski, who pioneered single crystal growth of metals from 1916). During this process, high purity polysilicon chunks are melted in a quartz crucible, a single crystal seed of silicon is lowered to just touch the melt and drawn up slowly. At the end of the process, a large single-crystal ingot has grown, replicating the structure of the seed.
Saint-Gobain Quartz is a supplier of quartz crucibles for single-crystal silicon ingot growth by the Czochralski method, of diameter up to 24 inches. Bubble-free inner layer crucibles are available for the most demanding applications.