AVS 52nd International Symposium
    Thin Films Thursday Sessions
       Session TF+EM-ThA

Paper TF+EM-ThA6
Effect of Dendrimer Underlayers on Sputtered Indium-Tin Oxide Thin Film Microstructure, Morphology, Optical and Electrical Properties

Thursday, November 3, 2005, 3:40 pm, Room 306

Session: Transparent Conducting Oxides
Presenter: R. Thunuguntla, The University of Alabama
Authors: R. Thunuguntla, The University of Alabama
S. Gupta, The University of Alabama
S. Street, The University of Alabama
D. Loy, The Army/ASUFlexible Display Center
Correspondent: Click to Email
Minimization of surface roughness is extremely important for sputtered indium-tin oxide (ITO) films used for organic light-emitting diode (OLED) applications. One of the techniques used to achieve smooth ITO films is the optimization of process parameters together with injection of cesium vapor into the plasma -- the recently-introduced negative sputter ion beam or NSIB process.@footnote 1@ We have investigated an alternative simpler approach -- the application of dendrimer monolayers by dip- or spin-coating techniques prior to ITO sputter deposition at ambient temperatures. The ITO films have been characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM), and the film microstructure and morphology have been correlated with the optical and electronic properties such as transmission, resistivity, mobility and carrier concentration. The presence of the dendrimer underlayer appears to mediate the film roughness by grain size reduction and improved adhesion. The greatest effect is seen in films sputtered at low powers. This is expected, since a high level of ion bombardment is expected to damage or destroy the dendrimer underlayer. The observed improvement is most encouraging for flexible display applications, where good film properties and low surface roughness are required at low deposition temperatures. @FootnoteText@ @footnote 1@ M. H. Sohn et al., J. Vac. Sci. Technol. A21(4), 1347 (2003).