Electrical, optical, and structural properties of indium–tin–oxide thin films for organic light-emitting devices

Journal of Applied Physics - Tập 86 Số 11 - Trang 6451-6461 - 1999
Heungsoo Kim1, C. M. Gilmore1, Alberto Piqué2, J. S. Horwitz2, Hedi Mattoussi2, Hideyuki Murata2, Zakya H. Kafafi2, Douglas B. Chrisey2
1School of Engineering and Applied Science, George Washington University, 725 23rd Street Northwest, Washington DC 20052
2Naval Research Laboratory, 4555 Overlook Avenue Southwest, Washington DC 20375

Tóm tắt

High-quality indium–tin–oxide (ITO) thin films (200–850 nm) have been grown by pulsed laser deposition (PLD) on glass substrates without a postdeposition annealing treatment. The structural, electrical, and optical properties of these films have been investigated as a function of target composition, substrate deposition temperature, background gas pressure, and film thickness. Films were deposited from various target compositions ranging from 0 to 15 wt % of SnO2 content. The optimum target composition for high conductivity was 5 wt % SnO2+95 wt % In2O3. Films were deposited at substrate temperatures ranging from room temperature to 300 °C in O2 partial pressures ranging from 1 to 100 mTorr. Films were deposited using a KrF excimer laser (248 nm, 30 ns full width at half maximum) at a fluence of 2 J/cm2. For a 150-nm-thick ITO film grown at room temperature in an oxygen pressure of 10 mTorr, the resistivity was 4×10−4 Ω cm and the average transmission in the visible range (400–700 nm) was 85%. For a 170-nm-thick ITO film deposited at 300 °C in 10 mTorr of oxygen, the resistivity was 2×10−4 Ω cm and the average transmission in the visible range was 92%. The Hall mobility and carrier density for a 150-nm-thick film deposited at 300 °C were 27 cm2/V s and 1.4×1021 cm−3, respectively. A reduction in the refractive index for ITO films can be achieved by raising the electron density in the films, which can be obtained by increasing the concentration of Sn dopants in the targets and/or increasing deposition temperature. Atomic force microscopy measurements of these ITO films indicated that their root-mean-square surface roughness (∼5 Å) was superior to that of commercially available sputter deposited ITO films (∼40 Å). The PLD ITO films were used to fabricate organic light-emitting diodes. From these structures the electroluminescence was measured and an external quantum efficiency of 1.5% was calculated.

Từ khóa


Tài liệu tham khảo

1999, Appl. Phys. Lett., 74, 3444, 10.1063/1.124122

1987, Appl. Phys. Lett., 51, 913, 10.1063/1.98799

1991, Thin Solid Films, 203, 297, 10.1016/0040-6090(91)90137-M

1994, Semicond. Sci. Technol., 9, 1242, 10.1088/0268-1242/9/6/014

1980, Appl. Phys. Lett., 37, 213, 10.1063/1.91829

1980, Thin Solid Films, 72, 463, 10.1016/0040-6090(80)90532-5

1990, Thin Solid Films, 193/194, 696, 10.1016/0040-6090(90)90221-X

1993, Appl. Phys. Lett., 63, 1, 10.1063/1.109736

1996, Thin Solid Films, 288, 248, 10.1016/S0040-6090(96)08824-4

1996, Appl. Surf. Sci., 96–98, 807

1980, J. Electrochem. Soc., 127, 1592, 10.1149/1.2129958

1982, Thin Solid Films, 90, 297, 10.1016/0040-6090(82)90381-9

1985, J. Phys. D, 18, 2087, 10.1088/0022-3727/18/10/019

1980, Thin Solid Films, 70, 91, 10.1016/0040-6090(80)90415-0

1975, Phys. Status Solidi A, 29, 87, 10.1002/pssa.2210290110

1981, J. Phys. D, 114, 1523

1979, Mater. Res. Bull., 14, 109, 10.1016/0025-5408(79)90238-1

1977, Phys. Thin Films, 9, 1

1973, Appl. Phys., 2, 247, 10.1007/BF00889507

1993, Thin Solid Films, 233, 135

1966, Phys. Status Solidi, 15, 627, 10.1002/pssb.19660150224

1954, Phys. Rev., 93, 632, 10.1103/PhysRev.93.632

1954, Proc. Phys. Soc. London, Sect. B, 67, 775, 10.1088/0370-1301/67/10/306

1986, J. Appl. Phys., 60, R123, 10.1063/1.337534

1991, Thin Solid Films, 196, 1, 10.1016/0040-6090(91)90169-X

1988, Appl. Surf. Sci., 33/34, 898, 10.1016/0169-4332(88)90396-0

1992, Appl. Phys. Lett., 60, 1541, 10.1063/1.107244

1979, Thin Solid Films, 59, 255, 10.1016/0040-6090(79)90298-0

1997, Thin Solid Films, 293, 244, 10.1016/S0040-6090(96)09105-5

1972, J. Electrochem. Soc., 119, 1368, 10.1149/1.2403999

1976, J. Appl. Phys., 47, 4086, 10.1063/1.323240

1997, Chem. Lett., 10, 963

1998, Appl. Phys. Lett., 73, 2721, 10.1063/1.122570

1998, Proc. SPIE, 3476, 88, 10.1117/12.332602

Thông tin
Thông tin xuất bản

Journal of Applied Physics

Tập 86 Số 11

6451-6461

Thông tin tác giả