Atomic layer deposition rate, phase composition and performance of HfO_2 films on noble metal and alkoxylated silicon substrates

摘要

HfO_2 films were grown by atomic layer deposition from HfCl_4 and H_2O on atomic layer deposited metal (Pt, Ir, Ru) films with rate exceeding that on SiO_2/Si substrates. The phase formed at any growth stages on metals was monoclinic HfO_2 without essential contribution from amorphous or metastable phases. The latter phases were prominent in the films on Si substrates functionalized with alcohol groups. The growth rate of amorphous HfO_2 from HfCl_4 or Hf[N(CH_3)_2]_4 and H_2O on functionalized Si was comparable to that on SiO_2 and higher than that commonly obtained on H-terminated Si surface. Instabilities in dielectric properties of HfO_2 could be reduced by post-deposition annealing. The Si surface functionalized with propanol groups promoted slightly more intense crystallization upon annealing, compared to butanol-functionalized surface.