Part II Functional Polymers for Semiconductor Applications Outline of

Part II. Functional Polymers for Semiconductor Applications Outline of Part Polymeric Insulator for Semiconductor Applications Introduction of Silicone Chemistry Theory of Sol-Gel Chemistry Organic-Inorganic Hybrid Polymer Semiconductor Insulating Materials Nanoporous Polysiloxane Materials Summary of Future Trends Prof. Jin-Heong Yim Functional Polymer/1st Semester, 2006 _________________________________________ Semiconductor Insulating Materials Prof. Jin-Heong Yim Semiconductor Insulating Materials Device performance is parasitized by RC delay in the case of deep sub-micron devices Prof. Jin-Heong Yim Why Low-k ? Prof. Jin-Heong Yim Dielectric Constant 유전율(ε) vs. polarizability(α) > 유전율 계산 A C = ε 0ε r d α dipole α ionicc α electronic 109 1012 (Hz) 1015 C : capacitance (@100kH ε : 유전율 > MIM 측정 구조 Al (5000A) Ti (100A) Al (5000A) Ti (100A) Low-k film Ti (100A) Al (2000A) Ti (100A) SiO2 (3000A) 2 Si Wafer ∆ε = ∆εe + ∆εi + ∆εd ε − 1 4π = ∑ N jα j ε +2 3 Prof. Jin-Heong Yim ITRS Roadmap Prof. Jin-Heong Yim Insulating Materials CVD Organic Parylene (2.5) Polynaphthalene (2.4) Spin-on Organic BCB (2.7) FLARE (2.8) Polyimide (2.7) Polyphenylene (2.65) Teflon (2.3) Organo silicate SiO2 (4.0) SiOF (3.5) SiOC(2.7) Organo silicate HSQ (3.1) MSQ (2.7) Xerogel (~2.0) Aerogel (~2.0) Requirement - Good Gap-fill (for Al interconnection) - Metal Corrosion Resistance - Good Thermal Stability (> 500oC) - Water Resistance - Good Adhesion - No issue for integration - No Crack (Mechanical Strength) Prof. Jin-Heong Yim Nanoporous Film is Needed! Needs Thermal stability (> 400 oC) Good mechanical property (>4GPa) Low water uptake Closed cell porosity (< 10 nm) Simplified lithographic processability Solution High performance siloxane polymer Unique small closed nano pore (<3 nm) Nano pore characterization New pattern process Polysiloxane matrix Nanoporous polysiloxane thin Nanoporous polysiloxane thin film is one of the promising film is one of the promising candidates. candidates. Prof. Jin-Heong Yim Air Substrate How to make porous thin film? Templating Approach Random PS Self-assembly Uni-molecular Hybrid system Nano Particle Thermal stable precursor Air Si Wafer Matrix precursor Nanoparticle Decomposition Porogen Spin-on XLK (Dow Corning) Lucent Tech. (2002) HSG (Hitachi) Philips (2002) LKD (JSR) JSR (2002) Si Wafer Porogen SAIT (2003) IBM (2004) Cal. Univ. (2001) NCS (CCIC) SAIT (2001) IBM (2003) Prof. Jin-Heong Yim Various Porogens 2000 2000 2001 Decomposable linear High boiling point Polymer; organic solvent Polyester, Polystyrene, PMS, Polyacrylate, PMA, ex) Tetradecane Polycarbonate Various polymeric Polynorbone based (b.p~250oC) Polyether Dendrimer Polymer IBM IBM Georgia Tech Dow Corning 2000 2001 2002 2002 2002 Non Ionic surfactant Polyakylene Oxide Ionic Surfactant Poly(caprolactone) + PEO PPO PEO N Br Poly(valeractone) C16TMABr PMMA Non Ionic surfactant Cyclodextrin based derivatives SAIT O O O O OH hydrophilic hydrophilic Mainly PEO/PPO AlliedSignal Inc. Cn EOx hydrophobic Lucent Technology JSR Prof. Jin-Heong Yim Porous Material via SA Prof. Jin-Heong Yim Surfactant Prof. Jin-Heong Yim Porogen Template Approach Prof. Jin-Heong Yim Various Porogens Prof. Jin-Heong Yim Polymeric Porogens Prof. Jin-Heong Yim Nanoparticle porogen via ROMP Prof. Jin-Heong Yim Forming Efficiency Prof. Jin-Heong Yim Porogen Template Method Prof. Jin-Heong Yim Closed Nanopore Prof. Jin-Heong Yim Morphological Transition Prof. Jin-Heong Yim Bicontinuous/Collapse Transition Prof. Jin-Heong Yim Sol-gel Approach Prof. Jin-Heong Yim Sol-gel Route to Porous Film Prof. Jin-Heong Yim Aerogel: Disordered Fractal Network Prof. Jin-Heong Yim Self Assembly Prof. Jin-Heong Yim Pore Structure Prof. Jin-Heong Yim Evaporation Induced Self Assembly (EISA) Prof. Jin-Heong Yim Typical Process Prof. Jin-Heong Yim Characteristics of EISA Prof. Jin-Heong Yim Material Structure-Property Relationships Prof. Jin-Heong Yim Dielectric constant vs Porosity Prof. Jin-Heong Yim Mechanical Property Prof. Jin-Heong Yim Nanoparticle Approach Prof. Jin-Heong Yim Zeolite ? Prof. Jin-Heong Yim Prof. Jin-Heong Yim Various Porous Film Prof. Jin-Heong Yim Characteristics Prof. Jin-Heong Yim Typical Process Prof. Jin-Heong Yim Patterned Structure Prof. Jin-Heong Yim Summary of Zeolite low-k Prof. Jin-Heong Yim Nanopore Analysis Prof. Jin-Heong Yim Nanopore Engineering Barrier Metal Issue Cu Diffusion Issue Ashing Damage Issue Blanket Film - Electrical Properties; k, Leakage current, Breakdown voltage - Young’s Modulus; Modulus, Hardness, Toughness Overall Properties - Film thickness - Refractive index - Film density & Porosity - Surface Area - Young’s Modulus Pore Structure - Open & closed pore size - Pore size distribution - Interconnectivity - Open & closed pore volume Prof. Jin-Heong Yim Nanopore Analysis Stereological Analysis SEM, FE-SEM Intrusive Method Gas Adsorption Mercury Porosimetry Calorimetric Method J. Rouquerol et al., Pure Appl. Chem., 66, 1739 (1994) Non-intrusive Method PALS, PAS D. W. Gidley et al., Appl. Phys. Lett., 76, 1282 (2000) XRR/SANS W. Wu et al., Appl. Phys. Lett., 87, 1193 (2000) XRR/SAXS T.P. Russel., MRS Bull., Jan. 49 (1996) - Need of radiation beam generator (Big facility) - PALS; Materials dependency (No generation and diffusion of Ps) Prof. Jin-Heong Yim TEM, HR-TEM Ellipsometric Porosimetry M.R. Baklanov et al., J. Vac. Sci. Tecnol., 18, 1385 (2000) - Qualitative analysis - Low contrast in amorphous materials (Low sensitivity) - Pore structure changing in the sample preparation - Limitation of closed pore system - Swelling issue of polymer film - Destructive method Nanopore Analysis PALS (Michigan Univ.) EP (IMEC) XRR/SANS (NIST) Detector PC Adsorptive Pump - Pore Size, PSD - Closed/Open Pore Shape - Interconnection Length - Porosity - Pore Size, PSD - Open/Closed Pore Volume - Young’s Modulus - Porosity - Pore Size, PSD Prof. Jin-Heong Yim PALS PALS technique provide: average pore size, PSD, pore shape (interconnectivity) o-PS: 75% (1) Micro pore Traped τ = 1-10 ns (2) Meso pore Traped τ = 10-140 ns (3) Escape to Vacuum τ = ~140 ns (4) Backscattered o-Ps τ = 142 ns p-Ps: 25% τ = 0.125ns Prof. Jin-Heong Yim EP EP technique provide: average pore size, PSD, porosity, shape info., modulus Simple vacuum equipment fits in-line process diagnosis detector No need for film scratch P PC Non-hazardous adsorptive pump adsorptive Laser probe determines the adsorbate amount. No need in large surface area Prof. Jin-Heong Yim XRR/SANS Prof. Jin-Heong Yim Summary Prof. Jin-Heong Yim