Absorbent for treating gases containing the materials used for

Abstract

An absorbent and process for removing materials for semiconductor products, such as SiH.sub.4, B.sub.2 H.sub.6, SeH.sub.2, AsH.sub.3, PH.sub.3, GeH.sub.4, SiH.sub.2 Cl.sub.2, SiHCl.sub.3, (CH.sub.3).sub.3 Al, (CH.sub.3).sub.3 Ga, etc. from a gas containing above toxic components. The absorbent includes a first and second dry absorbent. The first absorbent induces a solid carrier containing a large proportion of a porous inorganic silicate and impregnated with an aqueous solution of an alkali. The second absorbent has a solid carrier, similar to that in the first absorbent, being impregnated with an aqueous solution of an alkali and an aqueous solution of an oxidizing agent capable of oxidizing german. When used separately, these two absorbents are not capable of treating certain volatile inorganic hydrides or lose their capacity of absorption in a relatively short period for such hydrides. In order to fully treat a gas containing such toxic components, a third absorbent which also includes a porous solid carrier being impregnated with an aqueous solution of an oxidizing agent incapable of oxidizing german may be added the above first and second absorbents. The process includes appropriate combination of all or two of these absorbents performs an excellent treatment of a gas containing any compounds used for manufacturing semiconductors in two or three stages of the treatment.