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Furnaces are versatile, horizontal tube systems which can be used for a wide variety of oxidation, diffusion, heat treatment, and deposition processes. The tube furnaces in the three, four-stack systems at SNF can be divided into two categories: LPCVD systems (Low Pressure Chemical Vapor Deposition of various thin films -- for more information, look for this section of the main Equipment List) and atmospheric systems (for oxidation, doping, and annealing heat treatment.) Process capabilities of each furnace system are detailed in the Furnace Process Summary <PDF>.

Silicon nitride (or nitride or Si₃N₄₎ is deposited at moderately high temperatures (~800C) and low pressure (~250 mtorr), using dichlorosilane (SiCl₂H₂) and ammonia (NH₃). The deposition rate roughly ~30A/min for 4 inch wafers and ~35A/min for 3 inch wafers (depending on the specific recipe used and loading)..

Several different nitride deposition recipes are offered, which differ primarily in the resulting film stress value. For specific information about the recommended low stress nitride recipe (LSN850) which included recommended procedures for film characterization, please refer to the characterization report (courtesy of Eehern Wong).