An apparatus for depositing a solid film onto a substrate from a reagent
solution includes a reservoir of reagent solution maintained at a
sufficiently low temperature to inhibit homogeneous reactions within the
reagent solution. The reagent solution contains multiple ligands to
further control temperature stability and shelf life. The chilled
solution is dispensed through a showerhead onto a substrate. The
substrate is positioned in a holder that has a raised structure
peripheral to the substrate to retain or impound a controlled volume (or
depth) of reagent solution over the exposed surface of the substrate. The
reagent solution is periodically or continuously replenished from the
showerhead so that only the part of the solution directly adjacent to the
substrate is heated. A heater is disposed beneath the substrate and
maintains the substrate at an elevated temperature at which the
deposition of a desired solid phase from the reagent solution may be
initiated. The showerhead may also dispense excess chilled reagent
solution to cool various components within the apparatus and minimize
nucleation of solids in areas other than on the substrate. The apparatus
and its associated method of use are particularly suited to forming films
of II-VI semiconductors.