Quartz crucible is a vessel with strong temperature resistance and high purity,widely used in our daily lives.It has a good effect when pulling single crystals.But many people are not very familiar with the impact of oxygen content in product crystals.Next,let's learn about:
1.The main source of oxygen in single crystals
Although the melting point of the crucible is higher than that of the silicon material,the molten liquid silicon will corrode the crucible at high temperatures,causing a small amount of oxygen to enter the crystal.Near the melting point of silicon(1420),silicon is dissolved in a crucible,forming SIO and entering the silicon solution.Then silicon monoxide is transferred to the surface of the melt through mechanical convection,thermal convection,etc.So the silicon monoxide that reaches the surface of the silicon melt evaporates in the form of gas,while the remaining part of the silicon monoxide dissolves in the liquid silicon and enters the crystal in the form of oxygen atoms,thereby affecting the oxygen content of the single crystal.
2.Measures to prevent the release of oxygen content from crucibles
Oxygen mainly comes from quartz crucibles,so reducing the release of oxygen in the crucible is an important means to reduce the oxygen content of single crystals,and product quality directly affects the degree of release of the released material.In fact,the process of oxygen release in the crucible is the process of the bubble layer penetrating the transparent layer of the crucible and releasing oxygen into the silicon liquid.A transparent layer of about 3-5mm is sintered inside the crucible to ensure the purity of the inner surface of the crucible and prevent the softening point of the crucible from being too low.Therefore,the quality of the transparent layer of the crucible determines the degree of bubble release from the crucible.
The above is the impact of quartz crucible on the oxygen content in crystals that the editor shared with you.The sources of oxygen in single crystals and measures to prevent the release of oxygen content in crucibles were introduced separately.I hope it can help you use the quartz crucible more smoothly.