Hafnium oxide films were deposited on silicon substrates at deposition temperatures ranging from 190 to 500 °C by metalorganic chemical vapor deposition using an amide precursor, Hf[N(C2H5) 2]4, and O2 as source materials. The effect of deposition temperature on the deposition characteristics and electrical properties of the resultant films were investigated. Reaction-limited deposition of hafnium oxide films occurred at deposition temperatures under 380 °C. Concentration of residues, such as carbon, nitrogen, and hydrogen, monotonously decreased with increasing deposition temperature, with nitrogen being the most thermally susceptible. However, surface roughness reached a minimum value at 400 °C. Amorphous films were obtained for deposition temperatures up to 450 °C, but obviously became crystallized at 500 °C. Accumulation capacitance increased with increasing deposition temperature but saturated above 400 °C. Moreover, postdeposition annealing at 800 °C caused no obvious degradation in the electrical properties of the film deposited at 400 °C.
ASJC Scopus subject areas