Solid source precursor vessel

A reactant source vessel comprising:

• a container body having outer sidewalls and a bottom surface that define an internal area of the container body;
• a first plurality of parallel dividing walls extending between a first set of opposing sidewalls of the container body;
• and
• a second plurality of parallel dividing walls extending between a second set of opposing sidewalls of the container body, wherein the first and second plurality of dividing walls intersect to define a matrix of pockets within the internal area of the container body, each of the matrix of pockets configured to contain a volume of a solid source precursor, each of the matrix of pockets comprising at least one sidewall surface extending upward from the bottom surface of the container body, wherein the at least one sidewall surface defines an interior perimeter of the pocket;
• a lid having configured to engage the container body, the lid enclosing the internal area of the container body when connected to the container body;
• a fluid flow path defined by a bottom surface of the lid, the outer sidewall of the container and the first and second plurality of dividing walls, wherein the fluid flow path extends between an inlet end and an outlet end and passes over an upper surface of each of the matrix of pockets.