Characterization of the ultrathin HfO2 and Hf-silicate films grown by atomic layer deposition

The physical properties of HfO2 and Hf-silicate layers grown by the atomic layer chemical vapor deposition are characterized as a function of the Hf concentration and the annealing temperature. The peaks of Fourier transform infrared spectra at 960, 900, and 820 cm(-1) originate from Hf-O-Si chemical bonds, revealing that a Hf-silicate interfacial layer began to form at the HfO2/SiO2 interface after postdeposition annealing process at 600 degrees C for 1 min. Moreover, the intensity of the peak at 750 cm(-1) can indicate the degree of crystallization of HfO2. The formed Hf-silicate layer between HfO2 and SiO2 is also confirmed by X-ray photoelectron spectroscopy.