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The properties of WN[SUBx]C[SUBy] films deposited by atomic layer deposition (ALD) using WF[SUB6], NH[SUB3], and triethyl boron as source gases were characterized as a diffusion barrier for copper metallization. It is noted that the as-deposited film shows an extremely low resistivity of about 350 μΩ cm with a film density of 15.37 g/cm[SUP3]. The film composition measured from Rutherford backscattering spectrometry shows W, C, and N of ∼ 48, 32, and 20 at. %, respectively. Transmission electron microscopy analyses show that the as-deposited film is composed of face-centered-cubic phase with a lattice parameter similar to both β-WC[SUB1-x] and β-W[SUB2]N with an equiaxed microstructure. The barrier property of this ALD-WN[SUBx]C[SUBy] film at a nominal thickness of 12 nm deposited between Cu and Si fails only after annealing at 700 °C for 30 min. [ABSTRACT FROM AUTHOR]

Structural and electrical properties of gate stack structures containing ZrO[sub 2] dielectrics were investigated. The ZrO[sub 2] films were deposited by atomic layer chemical vapor deposition (ALCVD) after different substrate preparations. The structure, composition, and interfacial characteristics of these gate stacks were examined using cross-sectional transmission electron microscopy and x-ray photoelectron spectroscopy. The ZrO[sub 2] films were polycrystalline with either a cubic or tetragonal crystal structure. An amorphous interfacial layer with a moderate dielectric constant formed between the ZrO[sub 2] layer and the substrate during ALCVD growth on chemical oxide-terminated silicon. Gate stacks with a measured equivalent oxide thickness (EOT) of 1.3 nm showed leakage values of 10[sup -5] A/cm[sup 2] at a bias of -1 V from flatband, which is significantly less than that seen with SiO[sub 2] dielectrics of similar EOT. A hysteresis of 8-10 mV was seen for ±2 V sweeps while a midgap interface state density (D[sub it]) of ∼3x10[sup 11] states/cm eV was determined from comparisons of measured and ideal capacitance curves. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]