Production of single crystal silicon

Single crystal ingots are produced by Czochralski (CZ) or Magnetic Field Applied (MCZ) method at SUMCO. In CZ method, polycrystalline silicon purified by less than a few ppb (1 ppb = 1 part per billion) of metal content is molten together with dopants in a quartz crucible. The dopants, such as boron and phosphorus, are used for the adjustment of resistivity. Then, a small single silicon rod (seed) is placed on the molten silicon in an inert gas atmosphere at about 1400 degrees Celsius. As the seed is slowly rotated and pulled up from the melt, a single crystalline ingot with the same orientation as the seed is produced.

CZ crystal growers

Structure of a CZ furnace

Polycrystalline silicon in a quartz crucible	Single crystal growing