The next two bays contain "hot processing" equipment. Diffusion and oxidation furnaces bake electrically active impurities into the wafers or react silicon with O2 or H2O to grow SiO2 films.
CVD (chemical vapor deposition) chambers deposit new layers of material. Silicon can be deposited by immersing a wafer in hot silane (SiH4) gas. When these molecules land on a wafer surface, they decompose releasing hydrogen gas and leaving behind a silicon atom. In a similar manner, silicon nitride (Si3N4) can be deposited by the reaction of silane and ammonia gases.
