The Science of Process Exhaust Management
Joe Van Gompel
Glade Consulting, LLC
The byproducts of CVD, diffusion, and plasma etch processes are intimately tied to the process itself. The precursor materials (e.g. SiH4, TEOS, C3F8, WF6) have different properties and often require different abatement configurations. For example, interlayer dielectric etch uses fluorinated greenhouse gases and is a clean process with regard to process solids formation but requires specialized point-of-use (POU) equipment for F-GHG abatement. Conversely, aluminum etch (Cl2, BCl3) has no F-GHGs, but is challenging with regard to solids formation in the pipework. The Science of Process Exhaust Management Seminar has 3 primary areas of study. First is a survey of common chemicals used in semiconductor manufacturing with regard to their reactivity and likely process byproducts. Toxicity, corrosivity, and flammability are also considered. Understanding these properties enables the user to more clearly define POU requirements. Second is an overview of technologies (e.g. wet scrubbers, dry bed scrubbers, combustors, plasma) used for POU abatement. These are discussed with respect to efficacy to abate the process precursors and byproducts, and cost of ownership is also considered. Building on these, the third segment is a discussion of several common process types; etch, CVD, diffusion, implant, and more, and how these processes may be abated. A fourth topic will be presented which discusses aspects of F-GHG stability and abatement, followed by a tie-in to the EPA’s greenhouse gas reporting rule as it pertains to the electronics industry.