LCD (Liquid Crystal Display) OLED (Organic Light Emitting Diode) TV,,. 1) OLED LCD OLED LCD Fig. 1. OLED TV 2013 LG 55 OLED TV. SID (Society of Information Display) OLED (Fig. 2). OLED LCD, TFT. TFT 3. LCD (a-si), (p-si), (Oxide). (a-si) TFTLCD.,., (1 cm 2 /V S) 2,3) 4), OLED. (p-si) TFT. Fig. 1. OLED. 26
Fig. 2. SID 2013 () : LG Display UHD OLED Curved TV () : Samsung Display UHD OLED TV.. 100,. 5),, ( ).,..,.. (Fig. 3),.,., (E g > 3eV). 2004 Hosono et al. In-Ga-Zn-O 6). (Fig. 4)., 2p state. ns state, ns,.,, ns., InGaZnO. 7) Nomura et Fig. 3.. 27
Fig. 4. () :, () :. 6) al. ZnO, Ga 2O 3, In 2O 33. Fig. 5. Fig. 5 hall,. Fig. 5 In Zn.., Ga Ga,., Ga-O In-O Zn-O Fig. 5.. 8). 8), Ga. trade off.,. In, Ga, Ge, Ag, Au. In, Cd, Hg, Ti, Pb., Cu, Ag, Au., In Ga. 9-15) Fig. 6. In Ga Zr 9), Hf 10), La 11), Si 12), Mg 13), Sn 14), Al 15). OLED. LG OLED TV Sharp, AUO TFT OLED TV.,, 28
Fig. 6. ( :, : In Ga ).. TFT., LTPS (Low-Temperature Poly-Silicon)., OLED TFT. OLED TFTLCD (Switching) (Driving) On/Off. OLED TFT. OLED 2T1C (2 1 )., (Fig. 7) 17), 5~6 1~2.. OLED...,, (60 Hz 120, 240 Hz, : 1 On ). TFT.,, TFT TV 30 cm 2 /Vs. TFT, TFT OLED (Mobility, µ). LCD.., OLED. LCD,. 16)., Fig. 7. OLED (, 5T2C). 17) 29
. Oh et al. 18) IZO. In (In : 0.52 0.85, 7.2 cm 2 /Vs 41.0 cm 2 /Vs, 0.42 V/decade 0.20 V/decade)., -7.9 V (NBIS, V GS = V th-15 V, V DS = 10 V, = 2000, : 1.5 mw/cm 2, : ~ 600 nm).,. 19) Kim et al. 19) HIZO, IZO. HIZO, IZO. 10) IZO,. 18) HIZO/IZO. 43.24 cm 2 /Vs. Fig. 8 IZO HIZO/IZO NBIS NBIS., (Polycrystalline). 20) Indium-Tin-Oxide IZGO (> 20 cm 2 /Vs). 21) (2.5 atm, 5 atm). Kim et al. 22) ZnO. ZnO, Off. 17), ZnON. Fig. 9 ()ZnO 3.2 ev (Vacancy)... 23) ZnO ZnO (Valence band)..,. ZnON V DS = 10 V40 cm 2 /Vs.,. 40 cm 2 /Vs. (Conduction band),. Fig. 8. () : IZO NBITS. () : HIZO/IZO NBITS. ( : : 3 VG = -20V, VD = 10V, : 120lux, : 60C). 19) 30
Fig. 9. () : ZnO ZnON. () ZnO, ZnON, In2O3, Zn2O3 E-k. 20) Fig. 9(), ZnON ZnO. TFT. TFT. OLED TFT. OLED TFT LCD TFT. Fig. 10 OLED LCD. Fig. 10LCD TFT 1 1 (Capacitor). 1 TFT. LCD, On Off. LCD TFT Off., OLED TFT 2 1., TFT LCD, TFT (Driving)., Off, On. TFT 0.1 V, OLED 20%. 16)... Fig. 11,. (H 2O, O 2, H 2 ). Fig. 10. LCD OLED. 31
Fig. 11. /. Fig. 12. / (O2, H2O). 24) Fig. 12 24) + (+ 30 V),, ( O 2) (O 2(g)+e - O - 2(s)).,., O 2,., - (- 30 V),, H 2O. (H 2O (g)+h + H 2O + (s)),, H 2O... (Hole trapping).. 23),.,. 25) Yang et al. 25) Al-Sn-Zn-In-O (A)(B). Plasma Enhanced Atomic Layer Deposition (PEALD) 40 nm. 250C. Fig. 13A B. 10000, -20 V. A 31.4 cm 2 /Vs, 0.63 V, 0.14 V/decade, B A 0.77 V, 0.09 V/decade. (a) (b),,., (c) (d),. 0.72 V, 11.5 V..,. 32
Fig. 14.. Fig. 13. (a) : (NBS, Negative Bias Stress) A (b) : B NBS (c) : (NBIS) (d) : B NBIS. 25) (Bias Stress), (Temperature Stress), (Illumination Stress)......,. Fig. 14..,,., NBS (Negative Bias Stress), PBS (Positive Bias Stress). NBTS (Negative Bias Temperature Stress), PBTS (Positive Bias Temperature Stress). NBIS (Negativ Bias Illumination Stress), PBIS (Positive Bias Illumination Stress), NBITS (Negative Bias Illumination Temperature Stress), PBITS (Positive Bias Illumination Temperature Stress). 24, 26). Cross et al. 26) ZnO. p ZnO rf -30 V 1. 15. Fig. 15(). (Degradation).,. Liu et al. 24) IZO 33
Fig. 15. () : ZnO NBS ( : 1, : 15). 26) () : IZO NBS ( : 210-5 torr, : 3). 24). 210-5 torr, +30 V/-30 V 3. Fig. 15()... (BIS). Shin et al. 23) ZnO NBIS. On (+ 10 V ), Off (- 10 V ) 12, (peak) 540 nm, 515 nm 555 nm 0 1m W/cm 2. Fig. 16 ZnO. ZnO n On, Off., On, Off... ZnO n ZnO On (Major Carrier), (Minor Carrier). Off,. Fig. 16. (a): On/ (b) : On/ (c) : Off/ (d) : Off/. 23) 34
On.,. On., Off,,. Chowdhury et al. 27) IGZO -. IZGO.,. (NBTS). Park et al. 28) GIZO NBTS PBTS. GIZO Ga 2O 3/In 2O 3/ZnO 1:1:1. SiO x 200 nm SiO x 100 nm. Fig. 17 GIZO PBTS NBTS. 11000. 60C, PBTS +20 V, NBTS -10 V. 10.1 V.,.,. Kwon et al. 29) GIZO (Fig. 18). ES (Etch Stopper) BCE (Back Channel Etch). Etch Stopper ES, BCE. ES SiO x 200 nmpecvd (Plasma Enhanced Chemical Vapor Deposition), SiO x 200 nm PECVD. GIZO 70 nm. Fig. 19NBITS. 3 V GS= -20 V, V DS= 10 V, 180 lm/m 2. Fig. 19 () BCE, () ES., Etch Stopper. ES - 3.5 V, ES -0.8 V.. Kim et al. 30) (SiO x, SiON x, SiO x /SiON x) NBITS, Lee et al. 31) NBTIS. Fig. 17. () : GIZO NBTS () : GIZO PBTS. 28) (VG = -10V/+20V, VD = 10.1V, : 11000). Fig. 18. () : BCE TFT () : ES TFT. 29) 35
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