Pentacene-Based Organic

Thin-Film Transistor

Pentacene TFT ( u; /V s )

1977 () OTFT(organic thin-film transistor) ?flexible, low cost, low temperature process, various substrateDisplay devices, smart cards, inventory tag, large-area sensor array. a-Si TFT vs OTFTa-Si TFT(u=1.0) > OTFT(u=?) : , , -, ,

Pentacene /

Pentacene TFT OTFT parameter(u; /V s ) (1V/s) , 1. 2. / nm 3. (Vth)- insulator, ,Sub-threshold slope(SS; V/dec)-10 Vg gate (I on/off)

(1)Insulator O2 plasma 0.6 / OTS 1.6A.P.L 81, 2,2002, Jar B. BensigerPentacene Thermal is the fastest ways IEEE Electron Dev. 44.8.1997 T.N JacksonAdvanced matermal 10,5,1998 G.Howowitz ( 6 -)Pentacene deposition rate (APL 81,24,2002. Seongil.Im) (IEEE Elec,Dev.Let 18.3.1997) depo rate sub Bell lab journalPentacene orderingInorganic(SiO2) organic(PVA,PVP,PI) X//x chem.materal,13,2001 X.linda 0.25/0.006X//y APL 79,9,2001. M.L.Swiggers

(2)W/L (fringe effect outside channel)Pentacene(100nm), gold(150nm),SiO2(100nm) Depo (5*10^-6 torr)

IIBM J. Res & Dev, 45,1 C.D.DimitrakpoulosW/L is 10 or higher in order to minimize the effects of such currents;otherwise the mobility is overestimated time of flight ()

w/L -1248u0.450.280.260.14On/off10^-610^-610^-610^-6

Saturation

/ (), ()Off () , insulator Advanced Material 10,5,1998 Gilles.HorowitzInsulator Organic + organic/organic+ inorganic/inorganic+organic/inorganic+inorganicRing IEEE Trans.Electron Devices 46,6,1258,1999 T.N Jackson (10^-7)Ring (-9)Ain/Ai203 + PI

Gate/drain very high Gate/drain voltage - Science 283,5, 1999, J.M.ShawInsulator / BZT(Barium Zirconate titanate)Ar/O2 gas, 2.5*10^-3 toff, RTBaTiO3, Ta2O5, SrTiO3 : CVD ( not spin coatong)Pentacene Vt Insulator PVA (120nm)Ts Vt ( good) ( good)APL 83,15,3201 R.SchroedenglassgateInsulator - tiPentacene tssourcedrain

(1)Simplified deviceSource/drain/gate Ots 0.6 10^7But off APL 76.13.27 T.N. JacksonDouble pentacene layer 1.5/ on/off 10^8 Vt~0, ss~1.6V/dec-pentacene ordering/ void /carrier transport minus-void /film continuity /IEEE Elec.Dev.Lett 18.12 T.N.Jackson

(2)Top/bottom contact Top contact > bottom contact (sat region) 40 Thin Soilid Films 420-421 2002 Sengil ImWhy? Gate insulator areaTop contact < bottom contactJournal of Applied Physics 88,11,2000 T.N.Jackson

insulatorpentacenedrainsourceTop contactbottom contact

OTFT , OTFT BIBLE ?? , Current (x) pentacene insulator pentacene (PVA) insulator pentacene(PI) pentacene morphology Edge effect reducing model by multimodainRubbing pentacene ordering Double gate mobility xyz??

OTFT -Si 2 /V s , on/off ratio 10^8 >a-Si TFT 1, 1 , background OTFT control

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