Techniques for controlling a solid precursor vapor source are provided. An example method of controlling a solid precursor vapor source includes providing a carrier gas to a sublimation vessel containing a solid precursor material, wherein the carrier gas is heated with a carrier gas temperature control device prior to entering the sublimation vessel, measuring a temperature of a vapor exiting the sublimation vessel, and controlling a temperature of the carrier gas with the carrier gas temperature control device based at least in part on the temperature of the vapor exiting the sublimation vessel.