Thin films of ZrO 2 and HfO 2 have been deposited by liquid injection metal±organic (MO)CVD using a range of new alkoxide precursors, [Zr(O t Bu) 2 (mmp) 2 ] (1), [Hf(O t Bu) 2 (mmp) 2 ] (2), [Zr(mmp) 4 ] (3), and [Hf(mmp) 4 ] (4): (mmp = 1-methoxy-2-methyl-2-propanolate, OCMe 2 CH 2 OMe). The complexes are mononuclear and volatile, and are significantly less reactive to air and moisture than existing Zr and Hf alkoxide precursors such as [Zr(O t Bu) 4 ] and [Hf(O t Bu) 4 ]. The ZrO 2 and HfO 2 films were grown over a wide range of substrate temperatures (350±650 C), and analysis by laser Raman spectroscopy shows that the films were deposited in the thermodynamically stable a-or monoclinic phase.

4 ]. Varying levels of residual carbon and nitrogen were detected in the films grown from each precursor. Analysis by X-ray diffraction (XRD) indicates that films grown from both precursors exist predominantly in the thermodynamically stable monoclinic phase. Scanning electron microscopy (SEM) shows that the morphology of the HfO 2 films from each precursor is markedly different, with films deposited from [Hf(NMe 2 ) 4 ] having a well-defined columnar crystalline structure, whereas films grown from [Hf(ONEt 2 ) 4 ] are smoother with little evidence of columnar structure. Full crystal structure data for [Hf(NMe 2 ) 4 ] are given, and the dielectric properties of [Al/HfO 2 /n-Si(100)] MOS capacitors, fabricated using each precursor, are also reported.

HfO 2 films were grown by atomic layer deposition (ALD) from a new liquid precursor, Hf(ONEt 2 ) 4 and H 2 O, at temperatures between 250 C and 350 C on borosilicate glass and Si(100) substrates. The highest growth rate was achieved at 300 C, whereas the growth was essentially slower at 250 C and ceased at 350 C. The films possessed an O:Hf ratio of 2.15 ± 0.12, as determined by ion beam analysis. The films were weakly crystallized, showing X-ray diffraction (XRD) peaks characteristic of monoclinic phase. The refractive index of the films varied between 1.93 and 1.96. The effective permittivities of the dielectric layers in Al/HfO 2 /n-Si(100) capacitor structures were close to 10.

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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