A crystal is a material with a highly ordered microscopic structure of its constituents that form a crystal lattice. The process in which crystals are formed is called crystallization.
Crystal growth is an important stage in the crystallization process and there are a lot of methods used to encourage this process. Industrial furnaces can be used for crystal growth using a range of different methods. This blog post will outline some of the methods where an industrial furnace is used for crystal growth.
Bridgman-Stockbarger Method
This is a dual method approach, and the two techniques involved are similar yet have their distinct differences. This method is used to grow single crystal ingots primarily, but it can also be adopted to solidify polycrystalline ingots as well.
In this method, an industrial furnace is used to heat a polycrystalline material above its melting point and the material is then slowly cooled at the end of the container where the seed crystal is located. The seed material is grown through this method and progressively forms across the length of the container.
The distinction between the two techniques is very subtle, as they both use an industrial furnace with a temperature gradient from above the materials melting point to a slow cooling. The gradient for the Bridgeman method is produced at the exit of the furnace and is relatively uncontrolled, while the Stockbarger method modifies the technique to introduce a shelf separating two coupled furnaces with temperatures above and below the freezing point. This change enables better control over the temperature gradient.
Czochralski Method
The Czochralski method of crystal growth is used to achieve single crystals of semiconductors, salts, metals, and synthetic gemstones. The method involves using an industrial furnace to melt a material in a crucible to extract a large single-crystal cylindrical ingot from the melt.
In this method, a seed crystal is lowered into the melt to touch the top of the melted material, which causes the melt to go into equilibrium before the seed is slowly raised out of the melt. As it is raised out of the melt a crystal forms downwards.
Industrial Furnaces for Crystal Growth from Thermcraft
Thermcraft is a high-quality manufacturer of a range of thermal processing equipment, including industrial furnaces. We supply a range of standard models that can be used for crystal growing, and we can also design and build custom industrial furnaces to exact customer specifications.
If you would like any more information about our industrial furnaces for crystal growth, please contact us.