Silane gas venting/treatment lessons learned and best practices

Abstract

Silane (SiH₄) is a pyrophoric gas that requires special equipment and handling precautions to manage safely. Unfortunately, many users have had various serious accidents with SiH₄ equipment since popular inception of the gas in the late 1960s for semiconductor manufacture, including at least eight fatalities and many injuries. SiH₄ usage is growing tremendously worldwide in various industries, including semiconductor, flat-panel display, photovoltaic cell, and specialty glass manufacturing. Significant uses of SiH₄ also require systems with the capability to safely vent or treat SiH₄ gas—such as residual venting during container changes or emergency venting. Six hazards associated with venting and treating SiH₄ gas are presented in detail. Each hazard is illustrated by an actual venting incident and resulting lessons learned are discussed. Preferred venting and treatment solutions are detailed and a silane disposal system design work process is presented. Although the article is specific to pure SiH₄, it has relevance to both venting and treatment of pyrophoric gases and flammable gases that possess relatively low-ignition energies. © 2011 American Institute of Chemical Engineers Process Saf Prog 2011