Abstract: Methods for removing impurities from precursors and related systems are provided. A method comprises at least one thermal cycle. The at least one thermal cycle comprises one or more of the following steps: heating a vessel comprising a precursor and at least one impurity to a temperature for a duration sufficient to vaporize at least a portion of the at least one impurity; measuring a vapor pressure within the vessel to obtain a measured vapor pressure and comparing the measured vapor pressure to a set point vapor pressure; and when the measured vapor pressure is above or within the set point vapor pressure, removing, from the vessel, at least a portion of a vapor comprising the at least one impurity. Other methods and systems are provided herein.

Abstract: Molybdenum precursors with high purity and methods for purifying molybdenum precursors are provided. A method comprises obtaining a first vessel comprising a solid reagent; vaporizing at least a portion of the solid reagent to produce a vapor comprising a MoCl5 vapor and a molybdenum impurity vapor; flowing at least a portion of the MoCl5 vapor and at least a portion of the molybdenum impurity vapor to a second vessel; condensing at least a portion of the MoCl5 vapor in the second vessel to separate the MoCl5 from the molybdenum impurity; and removing at least a portion of the molybdenum impurity vapor from the second vessel to obtain a MoCl5 precursor.

Abstract: Systems and methods for controlling precursor delivery. The systems and methods may comprise a precursor delivery vessel in fluid communication with a gas flow line. The precursor delivery vessel may comprise at least one tray containing a vaporizable precursor. An amount of thermal energy may be supplied to the at least one tray in an amount sufficient to vaporize the vaporizable precursor. The vaporized precursor may be dispensed from the precursor delivery vessel to the gas flow line. The amount of thermal energy supplied to the at least one tray may be adjusted sufficient to maintain a pressure of the vaporized precursor, in the gas flow line, within a pressure range.