The thermal stability of lead bisdipivaloylmetanate [Pb(C 11 H 19 O 2 ) 2 ], used as a Pb source for the organometallic precursor in the metal±organic chemical vapor deposition MOCVD preparation of Pb-based ferroelectric films, was investigated. Using thermogravimetry differential thermal analysis (TG-DTA), with a heating rate of 10 K min ±1 and nitrogen as the carrier gas, the as-received specimen showed endothermic peaks at 132 C, and complete evaporation by 300 C. Isothermal mass loss analysis showed that, in the temperature range 100 C to 200 C, no degradation of the sample occurred. The specimen remained unchanged after being heated at 150 C for 1800 h in a sealed vessel. On the other hand, degradation occurred during the actual MOCVD process over 1500 h at 150 C. This decomposition was temperature dependent as no degradation was detected under CVD operating conditions over 2400 h at 140 C. Under CVD operating conditions, at 150 C, Pb(C 11 H 19 O 2 ) 2 continuously decomposed, decomposition products with a higher vapor pressure forming in the source container. Therefore, this decomposition is a characteristic feature of the MOCVD process in which the carrier gas flows through the source container.