Silane process
Thread Content
There are many manufacturers of polysilicon in China, but most of them use the trichlorosilane method for production； The silane method is not widely used; the most prominent examples of this method are those employed by Liujiu and Zhongning. As the name implies, this method involves using silane as a raw material to produce polysilicon. Since silane consists only of silicon and hydrogen, it is easier to control its purity compared to the trichlorosilane method. And the key to the entire process lies in producing qualified silanes. Both Liujiu and Zhongning use the same technology to produce silane, which is obtained by reacting sodium aluminum hydride with silicon tetrafluoride. The actual reaction is relatively simple; proper temperature control ensures the successful production of silane. However, since silane is highly flammable or explosive, pressure testing and leak detection are crucial. Sodium aluminum hydride is simply obtained by mixing hydrogen, sodium, and aluminum powder and reacting them under the action of a catalyst. The purity of silicon tetrafluoride has an impact on the distillation of silane, as impure gases from silicon tetrafluoride may end up in the crude silane, thereby increasing the workload or complicating the subsequent distillation process. Currently, both Liujiu and Zhongning are in the testing phase; Liujiu is progressing a bit more slowly, as testing has just begun there ； The progress in Zhongning is relatively fast; all tests in the workshops have now been completed, and it remains to wait for the final production of polysilicon. Who has more accurate information about Liuzhou 69 or Zhongning? I hope we can share it together. Thank you!
The equipment required for producing polysilicon is quite expensive; I heard that there is a polysilicon factory in Ningjin, Hebei.
The greatest advantage of the silane method is its low cost, while its biggest disadvantage is its high risk.
The silane method offers a high conversion rate but also a high degree of risk. Silane of high purity results in silicon of high purity; however, it requires strict process control, is prone to dangerous situations, and demands extremely high levels of sealing for the system
I heard that in late 2009, two attempts were made but driving the vehicle was not successful; it seems that Liu Jiu is still working on cleaning the equipment pipelines
Are all silane methods available? Could you provide information on these two manufacturers?
I have been to both of these factories! I think there’s still a long way to go before they can operate at full capacity; it would be good if they could operate normally this year
Zhongning has managed to produce it now, but the silane is purchased externally; synthesizing silane on its own has not yet been successful.
Is there a third one in the country now? ?
Comrades, everything we say and everything we do must be based on seeking truth from facts. No. . . . . Mislead others.
Waiting. Is there a more detailed introduction?