Byeong-Joo Lee Computational Thermodynamics Byeong-Joo Lee Computational Materials Science & Engineering Lab. Pohang University of Science & Technology

Byeong-Joo Lee R&D in Materials Science and Engineering Structure Evolution Process Condition Materials Property Research Type I : experiments first, then thinking Research Type II: think first, then do experiments

Byeong-Joo Lee Lattice Stability

Byeong-Joo Lee Regular Solution vs. Quasi-Chemical Model

Byeong-Joo Lee Thermodynamic Assessment – Cr-Ni Binary System B.-J. Lee, 1992 L fcc Cr,Ni = 8030 – ·T + (33080 – ·T)(1-2X Ni ) L bcc Cr,Ni = – ·T + (34418 – ·T)(1-2X Ni ) L liq Cr,Ni = 318 – ·T + (16941 – ·T)(1-2X Ni )

Byeong-Joo Lee Thermodynamic Calculation – Fe-Cr-Ni Ternary System

Byeong-Joo Lee Thermodynamic Parameters (Fe,Cr,Mo)(Va,B,C,N)

Byeong-Joo Lee Thermodynamic Calculation – Practical Steels

Byeong-Joo Lee Thermodynamic Calculation – Application to Alloy Design Computational Thermodynamics 의 적용 분야 Structural Materials (Steel, Solder, Al-, Ti-, Ni-, Mg-alloys), Semiconducting Materials, Ceramic Materials, Hydrogen Storage Materials, CVD process 등 열역학이 지배하는 모든 물질계

Byeong-Joo Lee AB1: 0.1C-5MN-7Al AB2: 0.2C-4Mn-6.6Al AB3: 0.3C-3.5Mn-6Al AB4: 0.4C-3.5Mn-5.8Al AB5: 0.5C-3Mn-4.9Al AB6: 0.3C-4Mn-7.3Al-0.05Ti Thermodynamic Calculation – Application to Alloy/Process Design

Byeong-Joo Lee Thermodynamics Assessment - Na-Al-H system

Byeong-Joo Lee Assessment of thermodynamic properties in the Li-Al-H ternary system

Byeong-Joo Lee ※ Example: Deposition of Silicon SiH 4 + 2Cl 2 = Si + 4HCl Driving force of CVD Deposition

Byeong-Joo Lee Interfacial Reactions

Byeong-Joo Lee Interfacial Reaction between Cu and Various Solder -Experimental Observation ▶ Cu/Sn : Cu 6 Sn 5 ▶ Cu/Sn-Pb eutectic : Cu 6 Sn 5 ▶ Cu/Sn-Ag eutectic : Cu 6 Sn 5 ▶ Cu/Sn-Zn eutectic : CuZn_γ ▶ Cu/Sn-In eutectic : Cu 2 (Sn,In) or Cu 2 In 3 Sn

Byeong-Joo Lee Application to Solder/Substrate Interfacial Reactions – Cu/Sn Reaction

Byeong-Joo Lee Application to Solder/Substrate Interfacial Reactions – Cu/Sn Reaction

Byeong-Joo Lee Application to Thin Film Reactions – Metal/Si Reaction

Byeong-Joo Lee Application to Thin Film Reactions – Metal/Si Reaction SiSample PreparationHeat TreatmentMeasurementAmorphousFirst Silicideref. crystal (111) triode d.c. sputtering bilayer (Ti: 95,400nm) isothermal (30min at 500 o C) XRD/TEM- Ti 5 Si 3 & TiSi 50 crystal (111) electron-gun deposition bilayer (Ti: 300nm) isothermal 120min at 500 o C RBS- a TiSi & TiSi 2 51 polycrystalmagnetron S-gun sputtering bilayer (Ti: 100nm) isothermal (40min at 600 o C) XRD- TiSi & TiSi 2 52 crystal evaporation bilayer (Ti:100nm) isothermal (30min at 750 o C) RBS/XRD- TiSi & TiSi 2 53 amorphous or electron-gun deposition bilayer (Ti: 90nm) isothermal (20min at 450 o C) Backscattering Spectroscopy - TiSi 54 crystal (111) electron-beam evaporation bilayer (Ti: 3nm) isothermal (30min at 600 o C) TEM- TiSi & TiSi 2 55 crystal (100) conventional HV sputtering bilayer (Ti: 30nm) isothermal (60min at 650 o C) RBS/TEM- TiSi 2 (C49) 56 crystal electron-gun evaporation bilayer (Ti: 140nm) isothermal (120min at 550 o C) RBS/XRD/TEM- b TiSi 2 57 amorphouselectron-beam evaporation trilayer (Ti: 10~100nm) isothermal (~300s at 560 o C) TEMyes SSA Ti 5 Si 3 45 amorphous or sputter-deposition a-Si/Ti/Si trilayer (Ti: 23nm) isothermal (60min at 500 o C) TEM/RBSyes SSA TiSi 2 (C49) 58 crystal (100) sputter deposition bilayer (Ti: 25~35nm) isothermal (30min at 460 o C) HRTEM/EDSyes SSA TiSi 2 (C49) 59 crystal (111) UHV e-beam evaporation a-Si/Ti/Si trilayer (Ti: 30nm) isothermal (30min at 450 o C) in-situ RHEED /HRTEM yes SSA c Ti 5 Si 3 60 poly Sirf sputtering bilayer (Ti: 55nm) heating (10 o C/m) to 510 o C XTEM/STEMyes SSA TiSi 2 (C49) 61 crystal (100) magnetron sputtering bilayer (Ti: 32,51nm) heating (15 o C/min) to approx. 800 o C IR-abs spect. XRD/resistivity yes SSA TiSi 2 (C49) 62 crystal (100) magnetron sputtering bilayer (Ti: 32,46nm) heating (3,20 o C/s) to approx. 800 o C in-situ XRD- Ti 5 Si 3 /Ti 5 Si 4 63

Byeong-Joo Lee Application to Thin Film Reactions – Metal/Si Reaction

Byeong-Joo Lee Application to Thin Film Reactions – Metal/Si Reaction

Byeong-Joo Lee Application to Interfacial Reactions – Metal/Si Reaction

Byeong-Joo Lee Application to Metal/Ceramics Interfacial Reactions – Ti/Al 2 O 3 Reaction

Byeong-Joo Lee Application to Metal/Ceramics Interfacial Reactions – Ti/Al 2 O 3 Reaction

Byeong-Joo Lee Computational Materials Science & Engineering Lab. Pohang University of Science & Technology, Korea Eunha Kim Inyoung Sa Byeong-Moon Lee and Byeong-Joo Lee Thermodynamics Nano Materials

Byeong-Joo Lee Size Effect on the Melting Point for Au nano particles & wires

Byeong-Joo Lee VLS Growth of Nanowires - GeSi Nanowires

Byeong-Joo Lee ② ①  Vapor-Liquid  Liquid-Solid SiH 4 + GeH 4 + H 2 Reactions during the VLS Process

Byeong-Joo Lee ② ①  Vapor-Liquid  Liquid-Solid ① ② SiH 4 + GeH 4 + H 2 Reactions during the VLS Process 200 torr 400 o C

Byeong-Joo Lee Size dependence of SiGe nanowire composition

Byeong-Joo Lee Size dependence of SiGe nanowire composition CALPHAD (2008)

Byeong-Joo Lee Summary Computational Thermodynamics Calculation of Multi-component Phase DiagramsCalculation of Multi-component Phase Diagrams Interfacial ReactionsInterfacial Reactions – Metal/Liquid Solder, Metal/Ceramics – Metal/Liquid Solder, Metal/Ceramics Thin Films ReactionsThin Films Reactions – Metal/Silicon – Metal/Silicon Thermodynamics of Nano MaterialsThermodynamics of Nano Materials – Capillarity Effect – Capillarity Effect