Synthesis of high conformalty Ti-Six-N films using (CH3)3CCl and SiH4; density functional theory simulation and film characterization

Jinho JEON; Hongsoo PARK; Dae Hong KO

doi:10.1016/j.tsf.2024.140435

Synthesis of high conformalty Ti-Si_x-N films using (CH₃)₃CCl and SiH₄; density functional theory simulation and film characterization

Jinho JEON, Hongsoo PARK, Dae Hong KO

Department of Materials Science and Engineering

Research output: Contribution to journal › Article › peer-review

Abstract

The step coverage of the atomic layer deposition (ALD) of Ti-N thin films was improved by the addition of (CH₃)₃CCl, and Si atoms were added during the Ti-N deposition to form a Ti-Si_x-N thin film. By ALD, four to eight cycles of the gas (CH₃)₃CCl/TiCl₄/NH₃ formed the Ti-N layer and, subsequently, one to two cycles of the gas SiH₄/NH₃ added Si atoms to formed the Ti-Si_x-N layer. The ALD process was repeated to form a thin film Ti-Si_x-N 150 Å (bilayer of (Ti-N) 80 Å + (Si_x-N) 70 Å) while adjusting the amounts of (CH₃)₃CCl and SiH₄. The crystallinity of Ti-N was studied by X-ray diffraction (XRD), and its composition was studied using X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The composition of the Ti-Si_x-N film was studied using electron energy loss spectroscopy and selected area electron diffraction, and its roughness was confirmed using atomic force microscopy. Transmission electron microscope was used to measures the thickness and composition of the Ti-Si_x-N film through location in a test pattern with an aspect ratio of 50:1. Step coverage improved to 99.9 % compared to conventional ALD Ti-N when using (CH₃)₃CCl. Additionally, (CH₃)₃CCl was more effective at lower temperatures (460 °C compared to 530 °C), and the effect of the (CH₃)₃CCl flow rate was saturated above 300 sccm. As the amount of (CH₃)₃CCl increased, the growth per cycle decreased from 0.29 Å/cycle to 0.15 Å/cycle. The addition of Si to the Ti-N film facilitated leakage gain by increasing the difference in the work function between the electrode and the capacitor, material but may have the side effect of pillar bending due to a decrease in crystallinity and hardness. We verified that the XRD (200)/(111) peak ratio decreased as the Si content increased. As a result, the optimal conditions for electrode Ti-Si_x-N were confirmed as follows: 300 sccm (CH₃)₃CCl Ti-N, SiH₄ 10 sccm Si_x-N combination. Furthermore, the Ti-Si_x-N layer can serve as the bottom electrode of a capacitor reduce the manufacturing process steps, and be a candidate for a solution for the electrode of the capacitor of a 5 nm node memory device.

Original language	English
Article number	140435
Journal	Thin Solid Films
Volume	801
DOIs	https://doi.org/10.1016/j.tsf.2024.140435
Publication status	Published - 2024 Jul 30

Bibliographical note

Publisher Copyright:
© 2024

All Science Journal Classification (ASJC) codes

Electronic, Optical and Magnetic Materials
Surfaces and Interfaces
Surfaces, Coatings and Films
Metals and Alloys
Materials Chemistry

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10.1016/j.tsf.2024.140435

Cite this

@article{f15b044401cd4dd4a2d92e4f755a2b12,

title = "Synthesis of high conformalty Ti-Six-N films using (CH3)3CCl and SiH4; density functional theory simulation and film characterization",

abstract = "The step coverage of the atomic layer deposition (ALD) of Ti-N thin films was improved by the addition of (CH3)3CCl, and Si atoms were added during the Ti-N deposition to form a Ti-Six-N thin film. By ALD, four to eight cycles of the gas (CH3)3CCl/TiCl4/NH3 formed the Ti-N layer and, subsequently, one to two cycles of the gas SiH4/NH3 added Si atoms to formed the Ti-Six-N layer. The ALD process was repeated to form a thin film Ti-Six-N 150 {\AA} (bilayer of (Ti-N) 80 {\AA} + (Six-N) 70 {\AA}) while adjusting the amounts of (CH3)3CCl and SiH4. The crystallinity of Ti-N was studied by X-ray diffraction (XRD), and its composition was studied using X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The composition of the Ti-Six-N film was studied using electron energy loss spectroscopy and selected area electron diffraction, and its roughness was confirmed using atomic force microscopy. Transmission electron microscope was used to measures the thickness and composition of the Ti-Six-N film through location in a test pattern with an aspect ratio of 50:1. Step coverage improved to 99.9 % compared to conventional ALD Ti-N when using (CH3)3CCl. Additionally, (CH3)3CCl was more effective at lower temperatures (460 °C compared to 530 °C), and the effect of the (CH3)3CCl flow rate was saturated above 300 sccm. As the amount of (CH3)3CCl increased, the growth per cycle decreased from 0.29 {\AA}/cycle to 0.15 {\AA}/cycle. The addition of Si to the Ti-N film facilitated leakage gain by increasing the difference in the work function between the electrode and the capacitor, material but may have the side effect of pillar bending due to a decrease in crystallinity and hardness. We verified that the XRD (200)/(111) peak ratio decreased as the Si content increased. As a result, the optimal conditions for electrode Ti-Six-N were confirmed as follows: 300 sccm (CH3)3CCl Ti-N, SiH4 10 sccm Six-N combination. Furthermore, the Ti-Six-N layer can serve as the bottom electrode of a capacitor reduce the manufacturing process steps, and be a candidate for a solution for the electrode of the capacitor of a 5 nm node memory device.",

keywords = "(CH)CCL, Atomic layer deposition, Capacitor electrodes, Memory device, Step coverage, Ti-Si-N",

author = "Jinho JEON and Hongsoo PARK and KO, {Dae Hong}",

note = "Publisher Copyright: {\textcopyright} 2024",

year = "2024",

month = jul,

day = "30",

doi = "10.1016/j.tsf.2024.140435",

language = "English",

volume = "801",

journal = "Thin Solid Films",

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publisher = "Elsevier B.V.",

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TY - JOUR

T1 - Synthesis of high conformalty Ti-Six-N films using (CH3)3CCl and SiH4; density functional theory simulation and film characterization

AU - JEON, Jinho

AU - PARK, Hongsoo

AU - KO, Dae Hong

PY - 2024/7/30

Y1 - 2024/7/30

N2 - The step coverage of the atomic layer deposition (ALD) of Ti-N thin films was improved by the addition of (CH3)3CCl, and Si atoms were added during the Ti-N deposition to form a Ti-Six-N thin film. By ALD, four to eight cycles of the gas (CH3)3CCl/TiCl4/NH3 formed the Ti-N layer and, subsequently, one to two cycles of the gas SiH4/NH3 added Si atoms to formed the Ti-Six-N layer. The ALD process was repeated to form a thin film Ti-Six-N 150 Å (bilayer of (Ti-N) 80 Å + (Six-N) 70 Å) while adjusting the amounts of (CH3)3CCl and SiH4. The crystallinity of Ti-N was studied by X-ray diffraction (XRD), and its composition was studied using X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The composition of the Ti-Six-N film was studied using electron energy loss spectroscopy and selected area electron diffraction, and its roughness was confirmed using atomic force microscopy. Transmission electron microscope was used to measures the thickness and composition of the Ti-Six-N film through location in a test pattern with an aspect ratio of 50:1. Step coverage improved to 99.9 % compared to conventional ALD Ti-N when using (CH3)3CCl. Additionally, (CH3)3CCl was more effective at lower temperatures (460 °C compared to 530 °C), and the effect of the (CH3)3CCl flow rate was saturated above 300 sccm. As the amount of (CH3)3CCl increased, the growth per cycle decreased from 0.29 Å/cycle to 0.15 Å/cycle. The addition of Si to the Ti-N film facilitated leakage gain by increasing the difference in the work function between the electrode and the capacitor, material but may have the side effect of pillar bending due to a decrease in crystallinity and hardness. We verified that the XRD (200)/(111) peak ratio decreased as the Si content increased. As a result, the optimal conditions for electrode Ti-Six-N were confirmed as follows: 300 sccm (CH3)3CCl Ti-N, SiH4 10 sccm Six-N combination. Furthermore, the Ti-Six-N layer can serve as the bottom electrode of a capacitor reduce the manufacturing process steps, and be a candidate for a solution for the electrode of the capacitor of a 5 nm node memory device.

AB - The step coverage of the atomic layer deposition (ALD) of Ti-N thin films was improved by the addition of (CH3)3CCl, and Si atoms were added during the Ti-N deposition to form a Ti-Six-N thin film. By ALD, four to eight cycles of the gas (CH3)3CCl/TiCl4/NH3 formed the Ti-N layer and, subsequently, one to two cycles of the gas SiH4/NH3 added Si atoms to formed the Ti-Six-N layer. The ALD process was repeated to form a thin film Ti-Six-N 150 Å (bilayer of (Ti-N) 80 Å + (Six-N) 70 Å) while adjusting the amounts of (CH3)3CCl and SiH4. The crystallinity of Ti-N was studied by X-ray diffraction (XRD), and its composition was studied using X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The composition of the Ti-Six-N film was studied using electron energy loss spectroscopy and selected area electron diffraction, and its roughness was confirmed using atomic force microscopy. Transmission electron microscope was used to measures the thickness and composition of the Ti-Six-N film through location in a test pattern with an aspect ratio of 50:1. Step coverage improved to 99.9 % compared to conventional ALD Ti-N when using (CH3)3CCl. Additionally, (CH3)3CCl was more effective at lower temperatures (460 °C compared to 530 °C), and the effect of the (CH3)3CCl flow rate was saturated above 300 sccm. As the amount of (CH3)3CCl increased, the growth per cycle decreased from 0.29 Å/cycle to 0.15 Å/cycle. The addition of Si to the Ti-N film facilitated leakage gain by increasing the difference in the work function between the electrode and the capacitor, material but may have the side effect of pillar bending due to a decrease in crystallinity and hardness. We verified that the XRD (200)/(111) peak ratio decreased as the Si content increased. As a result, the optimal conditions for electrode Ti-Six-N were confirmed as follows: 300 sccm (CH3)3CCl Ti-N, SiH4 10 sccm Six-N combination. Furthermore, the Ti-Six-N layer can serve as the bottom electrode of a capacitor reduce the manufacturing process steps, and be a candidate for a solution for the electrode of the capacitor of a 5 nm node memory device.

KW - (CH)CCL

KW - Atomic layer deposition

KW - Capacitor electrodes

KW - Memory device

KW - Step coverage

KW - Ti-Si-N

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U2 - 10.1016/j.tsf.2024.140435

DO - 10.1016/j.tsf.2024.140435

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AN - SCOPUS:85197063313

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JO - Thin Solid Films

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