The
process of making ultrapure polysilicon by the Siemens process
results in an unwanted secondary reaction forming oligomers and polymers
containing a silicon backbone. These byproducts accumulate in the
exhaust piping and downstream equipment used in the polysilicon manufacturing
process. They become extremely dangerous when exposed to moisture,
including moisture contained in ambient air, becoming intensely flammable
and shock-sensitive. This flammability is retained even in an inert
atmosphere. Tragically, these byproducts were involved in the deadly
explosion at the Yokkaichi Plant of Mitsubishi Materials Corporation
in Japan. The work presented here characterizes these byproducts in
their various states and provides insights into best practices for
treating piping and equipment fouled by these materials. An example
of the calculation of the energy released by ignition of these materials
in an industrial piece of equipment is included.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.