Entegris, Inc. NASDAQ: ENTG is a major provier of products and systems that purify, protect, and transport critical materials used in the semiconductor device fabrication process. The company seeks to help manufacturers increase their yields by improving contamination control in several key processes, including photolithography, wet etching & cleaning, chemical-mechanical planarization, thin-film deposition, bulk chemical processing, wafer and reticle handling and shipping, and testing, assembly and packaging.