Atomic Layer Deposition of Hafnium Dioxide Films from Hafnium Hydroxylamide and Water.

Abstract

Dielectric properties Dielectric properties D 9000Atomic Layer Deposition of Hafnium Dioxide Films from Hafnium Hydroxylamide and Water. -HfO 2 films are grown by atomic layer deposition from the new liquid precursor Hf(ONEt2)4 and H2O, at temperatures between 250 and 350°C on borosilicate glass and Si (100) substrates. The refractive index of the films varies between 1.93 and 1.96. The effective permittivities of the dielectric layers in Al/HfO 2 /n-Si(100) capacitor structures are close to 10. -(KUKLI*, K.; RITALA, M.; LESKELAE, M.; SAJAVAARA, T.; KEINONEN, J.; JONES, A. C.; TOBIN, N. L.; Chem. Vap. Deposition 10 (2004) 2, 91-96; Dep. Chem., Univ. Helsinki, SF-00014 Helsinki, Finland; Eng.) -W. Pewestorf 22-014

Atomic layer deposition chemistry, mechanisms and related physical properties of high permittivity dielectric oxides

“…On the other hand, the resulting films were very flat and possessed high refractive index with no essential interface layer as-deposited at around 250 OC [36]. In this way, 50.100 nm thick films of dominantly monoclinic phase [34] and 5-10 nm thick amorphous films [36] have been formed. In the ultrathin films with thickness lower than 10 nm, crystal growth became inhibited likely due to the low temperatures and high residual contents and the films remain amorphous.…”

“…This precursor is a liquid with relatively high vapor pressure and can thus be evaporated at temperatures considerably lower compared to halides: 60 "C. The suitable ALD temperatures range between 200 and 350 "C [34] enabling the growth of polycrystalline, preferably (200) and (020) oriented films. Higher growth temperatures possibly enhancing the decomposition may not be used.…”