Lina Ye

Organic light-emitting diodes with AZO films as electrodes

Abstract Aluminum-doped zinc oxide (AZO) films were prepared by r.f. magnetron sputtering. Organic light-emitting diodes (OLEDs) with AZO/ N , N ′-diphenyl- N , N ′-(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD)/tris(8-hydroxyquinoline)aluminum (Alq 3 )/Al configuration were fabricated. The electroluminescence and current–voltage ( I – V ) characteristics of the devices were studied and compared with those of tin-doped indium oxide (ITO) devices fabricated under the same conditions. The stability of both AZO/Alq 3 and ITO/Alq 3 interface was investigated with X-ray photoelectric spectrum (XPS). It was found that zinc or indium would diffuse into Alq 3 layer but the diffusive extent of zinc was lower than that of indium.

Bias voltage dependence of properties for depositing transparent conducting ITO films on flexible substrate

Abstract Good transparent conducting indium tin oxide films with good adherence were deposited on water-cooled polypropylene adipate substrate using bias r.f. magnetron sputtering. The films with resistivity as low as 6.3×10 −4 Ω cm and transmittance over 80% have been obtained by adjusting the bias voltage. It was observed that the structural, electrical and optical properties of the films depend on the bias voltage applied to substrate table.

ITO films deposited on water-cooled flexible substrate by bias RF Magnetron Sputtering

Abstract Indium tin oxide (ITO) films were deposited on water-cooled polypropylene adipate (PPA) substrate using bias RF magnetron sputtering from a ceramic target composed of In 2 O 3 (90%)+SnO 2 (10%). Good polycrystalline-structured ITO films with a low electrical resistivity of 6.3×10 −4 Ω cm have been obtained by applying a negative bias of about −40 V to the substrate at a water-cooled substrate temperature (18±2°C). The visible transmittance of all obtained films was over 80% and in the wavelength range of 400–550 nm, the transmittances increase with increasing the negative bias. X-ray diffraction spectra revealed that all the films oriented preferably with [222] direction and [400] diffraction peak decreased with increasing the negative bias. Both the X-ray diffraction spectra and atomic force microscope (AFM) measurement suggested that the average crystalline size, as well as the conductivity have a maximum value at the bias of about −40 V. The influences of argon pressure and the proportion of SnO 2 on the conductivity of the films were also studied. The optimum argon pressure is 0.5–1 Pa, and the proper content of SnO 2 is 7.5–10 wt.%.