Quartz crucible rupture sometimes occurs during the process of melting and crystal pulling, and the reasons for the rupture are as follows.
1.Improper method of melting.
1) Secondary crystallization.
When the upper silicon material flows down the inner wall of the quartz crucible to the bottom after melting, it often undergoes "secondary" crystallization due to the low temperature of the bottom, and the silicon material expands during the "secondary" crystallization and expands and cracks the quartz crucible.
2) Leakage of silicon after the bottom is turned.
When the upper molten silicon liquid flows along the wall of the pot to the bottom of the crucible, the bottom block and the quartz crucible are adhered together, when the upper silicon material is completely melted into liquid, the buoyancy force is formed on the bottom of the block, and when the buoyancy is large enough to separate the unmelted block from the bottom of the quartz crucible adhered to it, the crucible can often be broken.
2.The temperature of the melt is inappropriate
Too high a temperature of the melt will exacerbate the degree of crucible crystallization, increasing the likelihood of rupture.
3.Raw material issues
Too many impurities in the raw material or contamination during the cleaning and filling of the raw material will have an erosive effect on the quartz crucible, and in severe cases, molten silicon will penetrate into the inner layer of the crucible.
4.Graphite crucible problem
1) The calcination of the new graphite crucible is not thorough enough to put into use, which will cause serious crystallization of the outer layer of the quartz crucible.
2) The graphite crucible is greatly thinned due to the oxidation and degradation of its original thickness due to the long use time.
5.Quartz crucible problem
1) The quartz crucible is put in with excessive force, and the bottom is damaged and cracked.
2) When loading the bottom material, the large piece of silicon hits the bottom of the quartz crucible and causes hidden cracks.
3) The upper part of the crucible is loaded with too much material, and the bottom of the crucible is easy to break when the material collapses during the melting process, resulting in silicon leakage.
4) The quartz crucible has been cracked due to external damage, and the rupture occurs during the melting process.
6) Hidden cracks caused by damage during the production, packaging and transportation of quartz crucibles.
Note: Spread quartz knowledge, share industry topics, articles**Non-commercial use, there is infringement notice to delete!
The 2nd Anhui International Quartz Industry Conference and Exhibition 2024.