Patent ID: 6506256
Filing Date: 2003-01-14
Classification: H01L

Abstract:
An apparatus for diffusing an impurity into a semiconductor wafer comprising:a diffusion furnace tube which has a longitudinal center axis extending along a vertical direction and said diffusion tube having at least a gas injector vertically extending in a vicinity of an inner wall of said diffusion furnace tube and said gas injector having a single vertical alignment of a plurality of gas injection nozzles for blowing an impurity gas toward said longitudinal center axis in a first horizontal direction; and a wafer holder for holding at least one semiconductor wafer, said wafer holder being provided in said diffusion furnace tube so that said wafer holder rotates around a rotational axis extending along said vertical axis, whereby said at least one semiconductor wafer rotates around said rotational axis so as to keep a normal between said at least one semiconductor wafer and said rotational center axis, wherein when a center of said at least semiconductor wafer comes close to said injection nozzles, an included angle between said first horizontal direction along which said impurity gas is blown and a normal of said at least semiconductor wafer is in a range of 90 degrees Â±10 degrees.