Chih-Hung (Alex) ChangDepartment of Chemical Engineering Oregon State UniversityCorvallis OR 97331 Printable Thin Film Electronics• Solution-based additive process• Non-contact direct writing; no mask required • Large area roll-to-roll capability • Low manufacturing costAdvantages of Inkjet PrintingInkjet Printed Organic TFTsH. Sirringhaus et al. Science 290, 2123, 2000F8T2µfet =0.02 cm2/ V.s.Inkjet Printed Organic TFTsA.C. Arias et al. APL 85(15), 3304, 2004µfet =0.06 cm2/ V.s.Organic TFTs (Pentacene precursors in solvent as ink)Kawasaki et al, Proceedings of SPIE-The International Society for Optical Engineering, 5940, 2005 (µfet=0.15 cm2/V.s. Current on/off ratio = 105)Polymer TFTs (Polythiophene solution as ink)Arias et al, PMSE Preprints 92, 268, 2005 (µfet=0.1 cm2/V.s. Current on/off ratio = 107)Inkjet Printing of Organic Channel Materials for Thin Film TransistorsInkjet Printed Inorganic Materials: Metals• Ag, Au, Cu (using nanoparticle solution as ink)Inkjet Printed Inorganic Materials: Semiconductors• Inorganic TFTs (CdSe nanoparticlesolution as ink) Ridley et al, Science 286(5440),746,1999 (µfet=1 cm2/ V.s. ,current on/off ratio = 3.1x104)“Solution-processed silicon films and transistors” Tatsuya Shimoda et al. Nature, V440, 6 April 2006Inkjet Printed Inorganic Materials: SemiconductorsThermal Ink Jet Drop Ejection ProcessBubble nucleationRapid heatingproduces vapor explosion in inkBubble growthDrop formation & bubble expansionBubble collapse& drop break-offBubble collapse begins refillInk refill Refill inkSource: HPSubstrateSubstrateSubstratev0Liquid dropletdDroplet impact and spreadSolvent evaporate and form solid filmgDissolution & Re-crystallizationMechanism of Metal Oxide Thin Film FormationOSU Patent ApplicationSalt+WaterInkjet Printing Device Characterization• Field effect mobility, µfet~12.02 cm2 /V.s.•Current on/off ratio ~1e60.00E+002.00E-044.00E-046.00E-048.00E-041.00E-031.20E-030.00E+00 5.00E+00 1.00E+01 1.50E+01 2.00E+01 2.50E+01 3.00E+01 3.50E+01 4.00E+01Vds (V)Ids (A)Vg = -10Vg = 0Vg = 10Vg = 20Vg = 30Vg = 401.00E-091.00E-081.00E-071.00E-061.00E-051.00E-041.00E-031.00E-021.00E-011.00E+00-20-100 1020304050VgIdPatent Application SOLUTION DEPOSITION OF INORGANIC MATERIALS AND ELECTRONIC DEVICES MADE COMPRISING THE INORGANIC MATERIALSInventors: Chih-hung Chang, Doo-Hyoung Lee, and Yu-Jen Chang US utility patent application, OSU November 2006Toshiba, flexible low temperature polysiliconTFT LCDHeliovolts Solar SkinsPotential Applications• Displays• Thin Film Photovoltaics• Thin Film Batteries•Thin Film SensorsMarket Potential ?“Market for printable electronics will generate an estimated revenues of 7 billion US in 2010”- Nanomarkets Sep 2005Next Steps1. Competing technologies?a. Patent researchb. Strengthen patent position2. Market ?a. Market Research b. Market feedback for technology development3. Business Opportunity?a. License technology to existing companiesb. Create another venture with existing