INJECTION DISTRIBUTION DEVICE

摘要

Embodiments of the present disclosure generally relate to apparatus and methods for controlling injection profile. One embodiment provides an injection distribution device. The injection distribution device includes a shield portion and a baffle portion. The baffle portion comprises a first baffle having a plurality of first openings formed therethrough, and a second baffle having a plurality of second openings formed therethrough. At least a portion of the first baffle overlaps with the second. Some of the openings are arranged so that flow resistance through a baffle varies along a length of the baffle.