Flat Zone process
It is used to grow Si crystal having less contamination as compared to CZ process.
It is mainly used for high power,high voltage devices having high resistivity material , whereas the resistance is less in case of CZ process.
The purification of the crystals obtained through flat zone process is simple.
For high purity,poly crystalline silicon with a seed crystal at bottom is held in the vertical position and rotated.
The rod is enclosed in a quartz envelope within which an inert atmosphere (argon) is maintained.
During this process , a small zone of the crystal is kept molten by a radio frequency heater , which is moved from the seed in upward direction , so that the molten zone traverses the length of the rod.
CACKLE comment system
