Table 4-1 Summary of Ion0/Ioff ratio, S.S. and VTH0 on MOSFETs. p.79
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Figure Captions
Chapter 1 Introduction and Motivation
Chapter 2 Characterizations of High- κ Films Deposited by Atomic-Vapor
DepositionFig.2.1. Schematic diagram of atomic-vapor deposition (AVD) system p.26 Fig.2.2 XPS data of (a)Hf4f spectra, and (b)O1s spectra for HfO2 and HfO2+HfSiOx-IL films deposited 400A by AVD. p.27 Fig.2.3 XPS data of (a)Hf4f spectra, and (b)O1s spectra for HfO2 film deposited 40A by AVD. p.28 Fig.2.4 XRD spectra of HfO2 film deposited 400A by AVD.
PDA 600℃and 24h in N2 ambient. p.29 Fig.2.5 XRD spectra of HfO2+HfSiOx-IL films deposited 300A and 100A by AVD.
PDA 600℃and 24h in N2 ambient. p.29 Fig.2.6 XRD spectra of HfO2 film deposited 40A by AVD.
RTA 900℃and 30s in N2 ambient. p.30 Fig.2.7 Cross-sectional TEM images of TFTs incorporating HfO2 dielectric.
The thickness of HfO2 and IL are around 48.9nm and 1.5nm, respectively. p.31 Fig.2.8 Cross-sectional TEM images of TFTs incorporating two dielectrics of
HfO2+HfSiOx-IL. The thickness of HfO2, HfSiOx-IL and IL are around 37nm, 6.5nm and 1.0nm, respectively. (Spectrum 2) p.32
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Fig.2.9 TEM-EDX for composition ratios of Hf and Si from HfO2 dielectric on top
structure of Spectrum 2. p.32 Fig.2.10 Cross-sectional TEM images of TFTs incorporating two dielectric of
HfO2+HfSiOx-IL film. The thickness of HfO2, HfSiOx-IL and IL are around 37nm, 6.5nm and 1.0nm, respectively. (Spectrum 1) p.33 Fig.2.11 TEM-EDX for composition ratios of Hf and Si from HfSiOx-IL dielectric on
bottom structure of Spectrum1 p.33 Fig.2.12 Cross-sectional TEM images of TFTs incorporating HfO2 dielectric.
The thickness of HfO2 and IL are around 3.3nm and 2.0nm, respectively. p.34 Fig.2.13 XPS spectra of Hf4f for HfSiOx films deposited by AVD at various Hf/Si
composition ratios on Si (100). p.35 Fig.2.14 XPS spectra of Si2p for HfSiOx films deposited by AVD at various Hf/Si
composition ratios on Si (100). p.35 Fig.2.15 XPS spectra of O1s for HfSiOx films deposited by AVD at various Hf/Si
composition ratios on Si (100). p.36 Fig.2.16 XRD spectra of HfSiOx films deposited by AVD.
PDA 600℃and 24h in N2 ambient. p.36 Fig.2.17 XPS spectra of Hf4f for HfSiOx films deposited 40A by AVD at various Hf/Si
composition ratios on Si (100). p.37 Fig.2.18 XPS spectra of Si2p for HfSiOx films deposited 40A by AVD at various Hf/Si
composition ratios on Si (100). p.37 Fig.2.19 XRD spectra of HfSiOx films deposited 40A by AVD.
RTA 900℃and 30sec in N2 ambient. p.38 Fig.2.20 Cross-sectional TEM images of TFTs incorporating HfSiOx dielectric.
The thickness of HfSiOx and IL are around 34.6nm and 1.0nm, respectively. p.38
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Fig.2.21 Cross-sectional TEM images of TFTs incorporating HfSiOx dielectric.
The thickness of HfSiOx and IL are around 3.0nm and 1.6nm, respectively. p.39 Fig.2.22 XPS spectra of Hf4f for HfAlOx films deposited by AVD at various Hf/Al
composition ratios on Si (100). p.39 Fig.2.23 XPS spectra of Al2p for HfAlOx films deposited by AVD at various Hf/Al
composition ratios on Si (100). p.40 Fig.2.24 XPS spectra of O1s for HfAlOx films deposited by AVD at various Hf/Al
composition ratios on Si (100). p.40 Fig.2.25 XRD spectra of HfAlOx films deposited by AVD.
PDA 600℃and 24h in N2 ambient. p.41 Fig.2.26 XPS spectra of Hf4f for HfAlOx films deposited 40A by AVD at various Hf/Al composition ratios on Si (100). p.41 Fig.2.27 XPS spectra of Al2p for HfAlOx films deposited 40A by AVD at various Hf/Al
composition ratios on Si (100). p.42 Fig.2.28 XRD spectra of HfAlOx films deposited 40A by AVD.
RTA 900℃and 30sec in N2 ambient. p.42 Fig.2.29 Cross-sectional TEM images of TFTs incorporating HfAlOx dielectric.
The thickness of HfAlOx and IL are around 3.6nm and 1.7nm, respectively. p.43
Chapter 3 High-Performance Low-Temperature-Compatible N-Channel Polycrystalline Silicon TFTs Using High- κ Materials
Fig.3.1 Schematic flow charts for the fabrication of poly-Si TFTs. p.56 Fig.3.2 Schematic flow charts for the fabrication of capacitors. P.59 Fig.3.3 Plots of capacitance density versus gate voltage.
(a)HfO2, HfSiOx and HfAlOx p 60
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Fig.3.3 Plots of capacitance density versus gate voltage.
(b) HfO2, HfO2+HfSiOx-IL and HfSiOx (66% Si) p.60 Fig.3.3 Plots of capacitance density versus gate voltage.
(c) HfSiOx incorporation of 25%, 40% and 66% Si p.61 Fig.3.3 Plots of capacitance density versus gate voltage.
(d) HfAlOx incorporation of ~7%, 12% and 40% Al p.61 Fig.3.3 Summary of hysteresis for High-κ materials.
(e) HfO2, HfSiOx-IL, HfSiOx and HfAlOx p.62 Fig.3.4 Summary of effective dielectric constant for High-k materials. p.62 Fig.3.5 Frequency dispersion of normalized capacitance versus gate voltage for
(a)HfO2 (b)HfO2+HfSiOx-IL films after annealing at 600℃,
24h in N2 ambient. p.63 Fig.3.6 Frequency dispersion of normalized capacitance versus gate voltage for
HfSiOx incorporation of (a)66%, (b)40%, (c)25% Si after PDA at 600℃,
24h in N2. p.64 Fig.3.7 Frequency dispersion of normalized capacitance versus gate voltage for
HfAlOx incorporation of (a)40%, (b)12%, (c)~7% Al after PDA at 600℃,
24h in N2. p.66 Fig.3.8 Leakage current density versus capacitance equivalent thickness for High-κ materials after PDA at 600℃, 24h in N2 ambient. p.68 Fig.3.9 Leakage current density versus breakdown filed for High-κ materials. p.68 Fig.3.10 The plot of ID-VG for HfO2, HfSiOx-IL (66% Si), HfSiOx (66% Si) and
HfAlOx (40% Al). p.69 Fig.3.11 Summary of GIDL effect for High-κ materials. p.69 Fig.3.12 Summary of threshold voltage for High-κ materials. p.70
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Fig.3.13 Summary of On/Off current for High-κ materials. p.70 Fig.3.14 Summary of interface density of state for High-κ materials. p.71 Fig.3.15 Summary of subthreshold swing for High-κ materials. p.71 Fig.3.16 Summary of field effect mobility for High-κ materials. p.72
Chapter 4 High-Performance MOSFETs Using High- κ Materials
Fig.4.1 Schematic flow charts for the fabrication of MOSFETs. p.80 Fig.4.2 The plan-view Schematic for the fabrication of MOSFETs. p.81 Fig.4.3 Schematic flow charts for the fabrication of capacitors. p.82 Fig.4.4 Comparisons of transfer characteristics at VDS of 0.2 and 1.2V between
HfSiOx incorporation of 9% and 77% Si. p.83 Fig.4.5 Comparisons with various composition ratios of HfSiOx for subthreshold
swing. p.83 Fig.4.6 Comparisons of transfer characteristics at VDS of 0.2 and 1.2V between
HfAlOx incorporation of ~7% and 63% Al. p.84 Fig.4.7 Comparisons with various composition ratios of HfAlOx for subthreshold
swing. p.84 Fig.4.8 Comparisons with various High-κ materials for transfer characteristics at
VDS of 0.2 and 1.2V. p.85 Fig.4.9 Comparisons with HfO2, HfSiOx (12% Si) and HfAlOx (12% Al) for
subthreshold swing. p.85 Fig.4.10 Schematic for source/drain series resistance of HfSiOx (66% Si)
on MOSFETs. p.86 Fig.4.11 Comparison with threshold voltage correction between before and after
condition on MOSFETs. p.86
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Fig.4.12 Comparison with conductance correction between before and after condition on MOSFETs. p.87 Fig.4.13 Comparison with on/off current ratio correction between before and after
condition on MOSFETs. p.87 Fig.4.14 Summary of VTH correction at VDS of 0.1V for HfO2, HfSiOx and HfAlOx
films by RSD correction method. p.88 Fig.4.15 Comparison with various Al content in HfAlOx. p.88 Fig.4.16 Calculated fix charge with various Al content in HfAlOx. p.89 Fig.4.17 Summary of Ion correction at VDS=0.2V for HfO2, HfSiOx and HfAlOx
films by RSD correction method. p.89 Fig.4.18 Summary of Ioff correction at VDS=0.2V for HfO2, HfSiOx and HfAlOx
films by RSD correction method. p.90 Fig.4.19 Summary of Ion/ Ioff ratio correction at VDS=0.2V for HfO2, HfSiOx and
HfAlOx films by RSD correction method. p.90 Fig.4.20 Summary of thansconductance correction for HfO2, HfSiOx and HfAlOx
films by RSD correction method. p.91 Fig.4.21 Summary of mobility correction for HfO2, HfSiOx and HfAlOx films
by RSD correction method. p.91