Physical and electrical characteristics of atomic-layer-deposited Hf-silicate thin films using Hf[N(CH ₃)(C ₂H ₅)] ₄ and SiH[N(CH ₃) ₂] ₃ precursors

Hf-silicate films were grown by using atomic layer deposition with Hf[N(CH ₃)(C ₂H ₅)] ₄ and SiH[N(CH ₃) ₂] ₃ precursors. The composition of the Hf-silicate films was excellently well controlled by using the ratio of the deposition cycles of HfO ₂ and SiU ₂ (Hf/Si). The physical and the electrical characteristics of the Hf-silicate films were compared for Hf/Si = 3/1, Hf/Si = 1/1, and Hf/Si = 1/3. The relative Hf/(Hf+Si) compositions were 58%, 41%, and 25% for Hf/Si = 3/1, Hf/Si = 1/1, and Hf/Si = 1/3, respectively. The binding characteristics of the Hf-silicate films were shifted in the direction of higher binding energy with increasing of SiO ₂ portion, resulting in electric charging. The molecular structure of the Hf-silicate films was changed by the relative compositions of HfO ₂ and SiO ₂. In addition, the dielectric characteristics of the Hf-silicate films were directly proportional to the HfO ₂ portion.