Origin and effect of impurity incorporation in plasma-enhanced ZrO2 deposition

The origin of impurity incorporation in the ZrO2 films deposition by plasma-enhanced chemical vapor deposition with Ar-carried zirconium t-butoxide (ZTB) and O-2 was delineated by optical emission spectroscopy, quadrupole mass spectrometry, transmission Fourier transform infrared spectroscopy, and x-ray photoelectron spectroscopy. Hydrocarbons were the predominant contaminants in films obtained with only ZTB in the plasma, while their fractions decreased rapidly with the increasing O-2 to ZTB-carrying Ar flow rate ratio (O-2/Ar), and eventually became negligible in the oxygen-rich condition at O-2/Argreater than or equal to2. However, the increasing amount of oxygen led to the formation of hydrogen carbonate And formate from CO chemisorption at O-2/Ar=0.5 to mostly bidentate carbonate from CO2 chemisorption at O-2/Ar=2. The films from all conditions contained a significant amount of hydrogen-bonded hydroxyl groups. At higher O-2/Ar ratios, the decrease in hydrocarbon concentration and the increase in carbonate fractions resulted in the increase. in the dielectric constant. and the. negative oxide trapped charges. (C) 2003 American Institute of Physics.