Gas baffle and distributor for semiconductor processing chamber

A substrate processing chamber, the chamber comprising:

• an enclosure having a ceiling and a sidewall;
• a substrate support adapted to support a substrate;
• a gas distributor positioned centrally above the substrate support, the gas distributor comprising a body including a proximal portion with a threaded section having a first diameter, the proximal portion configured to couple the body to the ceiling of the enclosure, a concave portion extending from an upper boundary to a lower boundary of the concave portion, the concave portion extending along an arc having a first radius, a shoulder extending radially outward from the proximal portion to the upper boundary of the concave portion, a lower exposed surface including a central flat portion and a recessed peripheral flat portion separated from the central flat portion by a step, wherein the central flat portion extends radially from a center of the lower exposed surface to the step and has a second diameter greater than the first diameter, and a flange disposed between the concave surface and the lower exposed surface, the flange extending radially outward from the lower boundary of the concave portion to an outer edge of the body, wherein the concave portion and a portion of the flange form an upper exposed surface extending from the upper boundary of the concave portion and adapted to outwardly direct a gas away from the body and towards the enclosure sidewall, the concave portion comprising at least about 75% of an area of the upper exposed surface, the lower exposed surface spaced apart from the substrate support and adapted to inject a deposition gas into the substrate processing chamber.

A gas distributor for use in a gas processing chamber, the gas distributor comprising:

• a body including:
• a proximal portion including a threaded section having a first diameter, the proximal portion configured to couple the body to a wall of the semiconductor processing chamber;
• a concave surface extending from an upper boundary to a lower boundary of the concave surface, the concave surface extending along an arc having a first radius;
• a shoulder extending radially outward from the proximal portion to the upper boundary of the concave surface;
• a gas distributor face including a central flat portion and a recessed peripheral flat portion separated from the central flat portion by a step, wherein the central flat portion extends radially from a center of the gas distributor face to the step and has a second diameter greater than the first diameter;
• and
• a flange disposed between the concave surface and the gas distributor face, the flange extending radially outward from the lower boundary of the concave surface to an outer edge of the body, wherein the concave surface and a portion of the flange form a gas deflection surface extending from the upper boundary of the concave surface and arranged to deflect a gas from a first direction to a second direction, the flange including a convex surface disposed peripheral to the concave surface, and a transition surface disposed between the concave surface and the convex surface to provide a transition from the concave surface to the convex surface, wherein the convex surface comprises a maximum width across the body and the transition surface extends no more than about 20% of the maximum width.

A gas distributor for use in a gas processing chamber, the gas distributor comprising:

• a body including,
• a baffle to divert flow of a gas from a first direction to a second direction with a gas deflection surface, the gas deflection surface comprising a concave surface, a portion of convex surface, and a transition from the convex surface to the concave surface, the concave surface comprising at least about 75% of a surface area of the gas deflection surface, the transition comprising no more than about 10% of a maximum width across the body,
• a neck having a first diameter disposed near an upper end of the body,
• a lower exposed surface adapted to dispense a deposition gas through a plurality of jets, the lower exposed surface having a central portion and a recessed peripheral portion separated from the central portion by a step surface, wherein the central portion extends radially from a center of the lower exposed surface to the step surface and has a second diameter greater than the first diameter, the baffle disposed between the neck and the lower exposed surface,
• wherein the concave surface extends along the first direction near the neck of the body and extends along the second direction near the lower exposed surface,
• a gas inlet,
• a plurality of gas outlets disposed in the step surface,
• a gas passage connecting the inlet to the plurality of gas outlets, and
• wherein the gas distributor comprises a single piece of at least one of aluminum oxide or aluminum nitride and the gas deflection surface is generally rotationally symmetric about an axis extending substantially parallel to the neck, the first direction being substantially parallel to the axis and the second direction being substantially away from the axis.