Patent ID: 7758698

Claim:
A gas distributor for use in a semiconductor process chamber comprising a support, the gas distributor comprising: a body including: a neck having a first diameter, an upper end adjacent to the neck, a first channel extending from a first inlet disposed on the upper end to at least a first opening disposed on a lower surface of the body, the first channel adapted to pass a first fluid from a first fluid supply line in the support to at least the first opening, a second channel extending from a second inlet disposed on the upper end to at least a second opening disposed on the lower surface of the body, the second channel adapted to pass a second fluid from a second fluid supply line in the support to at least the second opening, wherein the body is generally rotationally symmetric about an axis extending along the body from the neck to a center of the lower surface of the body, a connector coupled to the neck and adapted to engage the support and hold the body in a predetermined rotational orientation about the axis such that the first channel is substantially aligned with the first fluid supply line and the second channel is substantially aligned with the second fluid supply line, a lateral seat extending outward from the neck, a concave surface extending from an outer periphery of the lateral seat outward and toward the lower surface of the body, and a baffle disposed between the concave surface and the lower surface of the body, wherein the lower surface of the body includes a central flat portion and a recessed peripheral flat portion separated from the central flat portion by a step, the first opening disposed on the step and the second opening disposed on the central flat portion, and wherein the central flat portion extends radially from the center of the lower surface of the body to the step and has a second diameter greater than the first diameter.