Plasma-enhanced atomic layer deposited HfO2 films using a novel heteroleptic cyclopentadienyl-based Hf precursor

Plasma-enhanced atomic layer deposition of HfO2 films using a novel (eta(5):eta(1)- Cp(CH2)(2)NMe)Hf(NEtMe)(2)(MAP-Hf01) precursor and Ar/O-2 plasma as a co-reactant was studied. Saturated atomic layer deposition with nearly constant growth per cycle of 0.65 angstrom/cycle was observed and the O/Hf ratio was similar to that of bulk HfO2 at deposition temperatures ranging from 200 degrees C to 400 degrees C. With increasing HfO2 deposition temperature, the crystallinity and density of the HfO2 film also increased; however, the concentration of OH-related defects and surface roughness showed the opposite tendency. Notably, HfO2 film deposited at 400 degrees C exhibited the lowest level of hafnium suboxide (HfOx) and the highest crystallinity in monoclinic phase. The high-quality HfO2 films produced over a well-defined ALD window demonstrate that MAP-HfO1 is a promising candidate for deposition of HfO2 in advanced microelectronics.