Impact of Deposition Processes on Properties of Atomic-Layer-Deposited Hafnium Zirconate High-k Dielectrics

In this article, we compare characteristics of atomic-layer-deposited hafnium zirconate (HfxZr1-xO2) high-k dielectrics formed with three different precursor combinations. The films studied are: (A) HfxZr1-xO2 deposited with hafnium(zirconium) tetrachloride and deuterated water, (B) HfxZr1-xO2 deposited with tetrakis(ethylmethylamino) (TEMA) hafnium(zirconium) and ozone, and (C) HfxZr1-xO2 deposited with TEMA-hafnium(zirconium) and oxygen plasma. In general, all films exhibit excellent physical and electrical properties. Tetragonal-phase stabilization was observed on all films with HfxZr1-xO2 deposited with TEMAHf(Zr)/O-3 showing higher tetragonality than HfxZr1-xO2 deposited with TEMAHf(Zr)/O-2 or Hf(Zr)Cl-4/D2O. Electrical results showed slightly better charge-trapping characteristics for HfxZr1-xO2 deposited with TEMAHf(Zr)/O-2 or O-3 than HfxZr1-xO2 deposited with Hf(Zr)Cl-4/D2O. (c) 2007 The Electrochemical Society.