GAS DIFFUSION SHOWER HEAD DESIGN FOR LARGE AREA PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION

摘要

Embodiments of a gas distribution plate for distributing gas in a processing chamber are provided. In one embodiment, a gas distribution plate includes a diffuser plate having an upstream side and a downstream side, and a plurality of gas passages passing between the upstream and downstream sides of the diffuser plate. At least one of the gas passages has a cylindrical shape for a portion of its length extending from the upstream side and a coaxial conical shape for the remainder length of the diffuser plate, the upstream end of the conical portion having substantially the same diameter as the cylindrical portion and the downstream end of the conical portion having a larger diameter.