Development of Sub-nano Scale of EELS Analysis Technique S. C. Lo 1,4 M. W. Lin 2 S. J. Chen 2 S. R. Lee 2 L. J. Lin 3 (MCL/ITRI) 1 2 3 (NTRC/ITRI) 4 147 TEM MIM TEM This report summarizes the achievements of TEM Group of Materials and Chemical Laboratories (MCL) in developing advanced electron microscopy analysis techniques which can be apply in advanced projects in ITRI. This report will showed the development of sub-nano scale EELS analysis technique. We developed ultra-thin TEM specimen preparation with thickness <50nm and high spatial resolution sub-nano scale (>0.5nm) EELS analysis technique. We believed the advanced electron microscopy analysis techniques will play an important role in the key issue in ultra-thin films, display and storage device development. / Key Words (Field Emission Transmission Electron Microscopy; FETEM) (Electron Energy Loss Spectrometer; EELS)(Ultra-thin Sample Preparation)(Spectrum-Imaging)
148 (Bulk Materials) (TiO 2 ) 30nm (1) (Sub-Å and Sub-eV) 200keV (JEOL JEM-2100F) 1.9 Å 1eV (2) (OLED)(OTFT) (Hybrid) (EELS) (3,4) EELS (50~100%) EFTEM Spectrum- Imaging (5) (Signal to Noise Ratio) (EELS Mapping) (5) MIM / / MIM 2nm~
L edge~73ev (Hafnium) M edge~1662ev 1000eV EFTEM Spectrum-Imaging 5~40sec 1 STEM Spectrum- Imaging (FETEM) JEOL JEM 2100F TEM (<50nm) (for Sub-nano EELS Analysis) TEM 1. TEM (<50nm) IBM - SEM (6-9) (Plan-view) 208 170 (8) (Ion Miller) Ion Miller 2. Metal-Insulator- Metal (MIM) AlCu/Ru/MIM/ TiN/Si 300nm GATAN PIPS <50nm EELS PIPS 100nm 50nm 2kV 2 <50nm 149
150 EELS EELS Thickness Map Ru (~60nm) <50nm 1. (Cs Corrector)(Monochromator) (Sub-Å and Sub-eV) FEI Company FETEM Titan TM (Sub-angstrom)(Sub-eV) (10) FEI Company Cs Corrector FETEM EDS Mapping 10 10 (~10pA to 150pA) EELS Mapping (11) Glass Specimen Microscope Specimen Reference: Hong Zhang, Micron, 33 (2002) p.515 Color Difference of the Si Dummy Sample Under Transmitted Light 10µm 8µm 6µm 4µm 2µm 4µm 6µm 8µm 10µm 60 nm OM Image of Sandwich Structure 0.1µm 0 EELS Thickness Map
(Transfer Function) X (X-ray Energy Dispersive Spectroscopy; EDS)(Electron Energy Loss Spectroscopy; EELS) (Scanning Transmission Electron Microscope; STEM) (S)TEM STEM (12) JEOL JEM-2100F 0.2nm STEM EDS EELS STEM EELS Spectrum-Imaging STEM EELS Spectrum-Imaging MIM 2. (Spectrum- Imaging) (Spectrum-Imaging) I (x, y, (E)) (EFTEM Spectrum-Imaging ) (a) (13) ( STEM Spectrum-Imaging ) 151 (a) CTEM Condenser Aperture 2β Screen 2α Specimen Objective Aperture Objective Lens Aberration Corrector (b) STEM Collector Aperture Annular Dark-field Detector Field-emission Source and Scan Coils CTEM STEM 12 X E (a) EFTEM (Image-Spectrum) Y (a) EFTEM Spectrum-Imaging (b) STEM Spectrum-Imaging X E (b) STEM (Spectrum-Imaging) Y
152 EELS-SI QDs Core-shell Particles John Silcox 2004~2005 S Signal Cd Signal (b) S (c) Cd 1 10 5 S Signal ADF Intensity 1600 8 10 4 (b) 1400 1200 6 10 4 4 10 4 1000 800 600 2 10 4 0 0 400 2 4 6 8 10 200 12 Position 4 10 4 1400 3.5 10 4 (c) Cd signal 1200 ADF Intensity 3 10 4 1000 2.5 10 4 800 2 10 4 600 1.5 10 4 1 10 4 400 5000 200 0 2 4 6 Position 8 10 12 ADF Intensity ADF Intensity John silcox 1. (0.2nm) EELS a. Core (CdSe)- shell (ZnS) Quantum Dot Coreshell b. VG HB501 100kV UHV STEM (Prode Size) 0.2nm NK-edge N.D. Browning 1. (0.2nm) EELS (a) Counts (arb. Units) 1nm 3 2 1 3 2 1 Counts (arb. Units) 3 O K-edge 2 (c) 1 400 420 440 460480 500 520 540560 (b) Energy Loss (ev) 3 2 1.6nm 1 Counts (arb. Units) (3) (2) (1) (d) Counts (arb. Units) Al-L (3) Si-L (2) (1) 80 100 120 140 160 Energy Loss (ev) a. (High-k Materials) b. JEOL JEM-2010F (200kV) 0.2nm (c) 525 530 535 540 545 550 555 560 565 Energy Loss (ev) 390 400 410 420 430 440 (d) Energy Loss (ev) (b) Si HfSiO Poly-Si 5nm Intensity (arb. Units) (c) Susanne Stemmer Santa Barbara 1. (0.3~0.5nm) EELS a. (High-k Materials) Counts (a. u.) Si Hf-si-O O K EELS N K EELS HfLα EDS Poly-Si Counts (a. u.) 0 2 4 6 8 10 Position (nm) Si Hf-si-O O K EELS N K EELS HfLα EDS Poly-Si b. FEI TECNAI F30 (300kV) 0.3~0.5nm 0 5 10 15 Position (nm) 0 5 10 15 Position (nm) Ref: 1. Zhiheng Yu et al., NANO LETTERS, Vol. 5, No.4 (2005) p. 565 2. R.F. Klie et al., Journal of Electron Spectroscopy and Related Phenomena, 143 (2005) p.105 3. Brendan Foran et al., Journal of Electron Spectroscopy and Related Phenomena, 143 (2005) P.149 (b) STEM Spectrum-Imaging JEOL JEM-2100F STEM Spectrum-Imaging <0.5nm 1.5~2 STEM Spectrum-Imaging
STEM Spectrum-Imaging 50nm 5nm Holder 3. (a) (b) EELS 60 40 Pixels 1 60 40 EELS Spectrum-imaging 50nm GATAN PIPS Holder 0.5nm >0.5nm TiN TiO 2 (HRTEM) Nano-scale EELS (a) Spectrum-Image Probe Spectrum x (b) Spectrum Line-Scan Probe Spectrum E (a) (b) 14 x E y y 153
154 Relative Composition (%) TiN/Al 2 O 3 /HfO 2 /Al 2 O 3 /TiN/Si Substrate 1000 C 20nm Spatial Drift Spectrum Image 1. Probe Size: 0.5nm 0.5nm 2. 0.5nm/Pixel (32nm/64pixels) Beam G1 Epoxy TiO /HfO 2 /TiO (mix TiN)/SiO 2 /Si Substrate 120 100 80 60 40 20 0 0 5 10 15 20 25 30 nm EELS O Ti N Si MIM TEM (<50nm) MIM PCM TEM (<50nm) MIM PCM TEM (<50nm) TiN/Al 2 O 3 /HfO 2 /Al 2 O 3 /TiN/Si Substrate 1000 C 1. Probe Size: 0.5nm 0.5nm 2. 30 33 Pixel (0.5nm/pixels) Si(B), Ti(G), O(R) Spatial Drift Spectrum Image 20nm 20nm Beam As-deposited EELS
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