abstract |
Methods and apparatus having a flow gradient created from a gas distribution plate are provided. In one embodiment, the method and apparatus are particularly useful for, but not limited to, depositing a silicon film for solar cell applications. The apparatus for depositing a uniform film for solar cell applications includes a processing chamber, and a quadrilateral gas distribution plate disposed in the processing chamber and having at least four corners separated by four sides. The gas distribution plate further includes a first plurality of chokes formed through the gas distribution plate, the first plurality of chokes located in the corners, and a second plurality of chokes formed through the gas distribution plate, the second plurality of chokes located along the sides of the gas distribution plate between the corner regions, wherein the first plurality of chokes have a greater flow resistance than that of the second plurality of chokes. |