Transparent conducting Zr-doped In2O3 thin films for organic light-emitting diodes

Zirconium-doped indium oxide (ZIO) thin films (similar to 2000 Angstrom thi ck) have been deposited by pulsed-laser deposition on glass substrates with out a postdeposition anneal. The structural, electrical and optical propert ies of these films have been investigated as a function of substrate temper ature and oxygen partial pressure during deposition. Films were deposited a t substrate temperatures ranging from 25 degreesC to 400 degreesC in O-2 pa rtial pressures ranging from 0.1 to 50 mTorr. The films (similar to 2000 An gstrom thick) deposited at 200 degreesC in 25 mTorr of oxygen show electric al resistivities as low as 2.5x10(-4) Omega cm, an average visible transmit tance of 89%, and an optical band gap of 4.1 eV. The ZIO films were used as a transparent anode contact in organic light emitting diodes and the devic e performance was studied. The external quantum efficiency measured from th ese devices was about 0.9% at a current density of 100 A/m(2). (C) 2001 Ame rican Institute of Physics.