Atomic Layer Deposition of Hafnium Oxide Using Anhydrous Hafnium Nitrate

Abstract

Atomic layer deposition of uniform thin hafnium oxide films has been demonstrated directly on H-terminated silicon surfaces using anhydrous hafnium nitrate precursor and vapor. Atomic layer deposition was initiated on hydrogen terminated silicon surfaces and occurred at substrate temperatures as low as 160°C. X-ray diffraction analysis indicated that as-deposited films were smooth, uniform, and amorphous, and that film morphology can be altered by a post-deposition anneal. X-ray photoelectron spectroscopy analysis indicated that films are oxygen rich, contain silicate, and that residual and from the precursor can be eliminated by a post-deposition anneal. For a ∼57 Å film, a dielectric constant of and a capacitive equivalent thickness of ∼21 Å were obtained. © 2002 The Electrochemical Society. All rights reserved.