Ju Youn Kim

Remote plasma enhanced atomic layer deposition of TIN thin films using metalorganic precursor

TiN films were deposited by remote plasma enhanced atomic layer deposition (PEALD) method using tetrakis-dimethyl-amino-titanium precursor and hydrogen, hydrogen/nitrogen mixture, and nitrogen plasmas. Remote PEALD method showed a relatively wide temperature window compared to that of conventional ALD process due to the increased reactivity of reactant gas. TiN films showed significantly lower impurity contents than those of the films deposited by other methods such as plasma enhanced chemical vapor deposition, metalorganic chemical vapor deposition, and conventional ALD using the same precursor. TiN films deposited using N2 plasma showed better characteristics than the films deposited using H2 and H2/N2 mixture plasmas. TiN films deposited by remote PEALD at 250 °C showed the resistivity value as low as about 300 μΩ cm and exhibited excellent conformal step coverage on 0.25-μm-wide and 2.5-μm-deep contact hole structure.

Comparison of TiN Films Deposited Using Tetrakisdimethylaminotitanium and Tetrakisdiethylaminotitanium by the Atomic Layer Deposition Method

TiN films were deposited by the atomic layer deposition (ALD) method using either tetrakisdimethylaminotitanium (TDMAT) or tetrakisdiethylaminotitanium (TDEAT) as the Ti precursor and NH3 as the reactant gas. The TiN films deposited using TDMAT showed two saturated TiN film growth regions which were observed in the temperature ranges between 175 and 190°C and between 200 and 210°C. The TiN films deposited using TDEAT showed a saturated growth rate in the temperature range between 275 and 300°C. The growth rates of the TiN films deposited using either TDMAT or TDEAT were about 5 and 1 A/cycle, respectively. The TiN films grown by the ALD method showed relatively low carbon content compared to the TiN films deposited by other conventional chemical vapor deposition and metalorganic chemical vapor deposition methods using the same precursors. The resistivity of the TiN films deposited by the ALD method was below 1,000 µΩcm. The TiN films deposited using TDEAT showed a lower resistivity than the films deposited using TDMAT. The calculated densities of the TiN films deposited using either TDMAT or TDEAT were about 3.55 and 4.38 g/cm3, respectively. This paper presents a comparison of the characteristics of the TiN films deposited using the two different precursors, TDMAT and TDEAT.

Characteristics of TiN Films Deposited by Remote Plasma-Enhanced Atomic Layer Deposition Method

In this paper, we report a remote plasma-enhanced atomic layer deposition (PEALD) method which shows a relatively wide temperature window compared to the conventional ALD process due to the increased reactivity of reactant gas as well as the increased reactivity of active nitrogen radicals in the plasma process. The remote PEALD TiN films we produced showed significantly lower impurity contents than films deposited by other methods such as plasma-enhanced chemical vapor deposition (CVD), metal-organic CVD or other ALD using the same precursor. TiN films deposited by remote PEALD at 250°C showed a resistivity value as low as approximately 300 µΩcm and exhibited excellent conformal deposition with almost above 95% step coverage on a 0.25-µm-wide and 2.5-µm-deep contact hole structure.

Characterization of remote inductively coupled CH4-N2 plasma for carbon nitride thin-film deposition

We investigated reaction characteristics in a CH4∕N2 plasma for deposition of amorphous CNx thin films (a-CNx) by evaluating the change in electron density using the wave cutoff method, and the behavior of ions and radicals with an optical emission spectroscopy (OES). An inductively coupled plasma source that was 30cm away from the substrate stage was used for the discharge. The change in electron density in the substrate region and OES spectra in the plasma-source region were evaluated to investigate both the reaction mechanism and the remote effect while varying process conditions such as rf power, pressure, and gas-mixing ratio. We found that the electron density in the remote CH4∕N2 plasma was closely related to recombination reactions of major ions such as N2+, CH4+, CH3+, and H2+ during diffusion from the plasma source to the substrate. The electron density and optical emission of major ions and radicals in the CH4∕N2 plasma increase at higher rf power. The ratio [N]∕([N]+[C]) in a-CNx films, as mea...

Deposition and Plasma Measurements of Zr-Oxide Films with Low Impurity Concentrations by Remote PEALD

Zr-oxide film was deposited by remote plasma-enhanced atomic layer deposition (PEALD) and showed relatively low impurity contamination. In the Zr-oxide film deposition process, the plasma diagnostics were performed to investigate the effects and characteristics of O 2 remote plasma. The carbon contents in Zr-oxide film were decreased with increasing rf power. The electron density and optical emission of species were measured using cutoff and optical emission spectroscopy during the deposition. The electron density in O 2 remote plasma was about 7.8 X 10 9 to 2.1 X 10 1 0 cm - 3 . The dominant emission species of O 2 remote plasma was the excited atomic and molecular oxygen.

Compositional Variations of TiAlN Films Deposited by Metalorganic Atomic Layer Deposition Method

We investigated compositional variations in TiAlN films grown by the atomic layer deposition (ALD) method at a relatively low temperature (200?C) and their effects on the barrier characteristics for copper metallization. TiAlN films were deposited using tetrakis-dimethyl-amino-titanium (TDMAT) as the titanium precursor, dimethylaluminum-hydride-ethylpiperidine (DMAH-EPP) as the aluminum precursor and NH3 as the reactant gas. Three samples of different compositions were prepared by controlling the number of TDMAT?NH3 and DMAH-EPP?NH3 processing cycles. Titanium and aluminum contents corresponded well with each of the precursor processing cycles while the nitrogen incorporated remained relatively constant. The oxygen and carbon contents were strongly dependent on the aluminum and titanium contents. The TiAlN film exhibited an amorphous structure and the amorphous characteristics remained even at an annealing temperature as high as 900?C. The titanium-rich TiAlN film showed lower resistivity (?1500 ???cm) than the aluminum-rich film. This study demonstrated composition controllability of ALD techniques by simple manipulation of the processing cycle of each precursor and revealed improved barrier characteristics of TiAlN.

Thermal Stability of ALD HfO2 Thin Films and Interfacial Layers on the Oxynitride Underlayer Formed Using Remote Plasma

Small amounts of N atoms were successfully incorporated by remote nitrogen plasma treatment into an oxynitride underlayer for the growth of an atomic layer deposited (ALD) HfO 2 thin film. As the electron density and emission intensity of nitrogen plasma increased with plasma power, the concentration of incorporated N atoms increased. The dominant emission species in the N 2 plasma were excited atomic nitrogen (N*) and excited molecular nitrogen (N* 2 ). Due to the oxynitride layer, the growth of the interfacial layer in HfO 2 films was effectively suppressed, the crystallization temperature of HfO 2 films increased, and the electrical properties were improved.