Methods and equipment for forming ternary metal alloys are provided. In some embodiments, TaCN thin films are deposited by exposing a substrate to alternating pulses of an organometallic tantalum precursor comprising nitrogen and carbon and hydrogen plasma. The stoichiometry of the film is tuned from carbon rich to nitrogen rich by adjusting the plasma parameters, particularly the plasma power and duration. In this way, films with varied characteristics can be formed from the same precursor. For example, both n-type and p-type materials can be deposited in the same module using the same precursor.