Infrared characterization of hafnium oxide grown by atomic layer deposition using ozone as the oxygen precursor

Hf O 2 growth on H-terminated Si surfaces by atomic layer deposition (ALD) is studied with in situ Fourier transform infrared spectroscopy and ex situ Rutherford backscattering, using tetrakis-(ethyl-methyl-amino) hafnium and ozone as the hafnium and oxygen precursors, and compared to water-vapor-based ALD growth. The reaction pathways are different for the two oxygen precursors, leading to a lower growth rate for ozone ( ∼ 0.05 nm ∕ cycle ) than for water-based growth and to incorporation of different impurities in the Hf O 2 film. Furthermore, interfacial Si O 2 is readily formed with ozone at the growth temperature ( ∼ 100 ° C ) , in contrast to water-based Hf O 2 growth.