Hydride vapor-phase deposition (HVPE) systems are disclosed. An HVPE hydride vapor-phase deposition system may include a reactant source chamber and a growth chamber containing a susceptor coupled to the reactant source chamber. The reactant source chamber may be configured to create a reactant gas through a chemical reaction between a solid or liquid precursor and a different precursor gas. The reactant source chamber can be configured to operate at a temperature T(M) significantly above room temperature. The reactant gas can be chemically unstable at or near room temperature. The susceptor is configured to receive a substrate and maintain the substrate at a substrate temperature T(S). The growth chamber includes walls can be configured to operate at a temperature T(C) such that T(M), T(S) are greater than T(C).