AVS 45th International Symposium
    Thin Films Division Monday Sessions
       Session TF-MoP

Paper TF-MoP6
Influence of Annealing Temperature on the Formation and Characteristics of Sol-gel Prepared ZnO Films

Monday, November 2, 1998, 5:30 pm, Room Hall A

Session: Thin Films Poster Session
Presenter: G. Torres-Delgado, Cinvestav-IPN, Mexico
Authors: R. Castanedo-Pérez, Cinvestav-IPN, Mexico
O. Jiménez-Sandoval, Cinvestav-IPN, Mexico
S.J. Jiménez-Sandoval, Cinvestav-IPN, Mexico
A. Maldonado-Alvarez, Cinvestav-IPN, Mexico
J. Márquez-Marín, Cinvestav-IPN, Mexico
G. Torres-Delgado, Cinvestav-IPN, Mexico
Correspondent: Click to Email
ZnO films have been obtained by the sol-gel method, from a Zn(OOCCH@sub 3@) precursor, on silica glass and silicon wafer substrates. The films, obtained by a single dipping procedure, were characterized by FT-IR and UV-VIS spectroscopy, atomic force microscopy, X-ray diffraction and ellipsometry measurements. Untreated and single-step, annealed (100-450°C) films were studied, in order to analyze the influence of temperature on the formation and properties of the ZnO coatings. Remarkably, these results indicate that ZnO forms at considerably lower temperatures than 450°C, which is usually considered in literature as a reference temperature for the formation of ZnO. Thus, a sharp absorption edge of ZnO at ca. 380 nm, can be neatly observed in the UV-VIS spectra of films annealed at 200 and 300°C, and accordingly, IR data indicate the absence of organic groups at these temperatures. Somewhat surprisingly, at 400 and 450 °C, the ZnO optical absorption edge is not as sharp as is at lower temperatures. Atomic Force Microscopy results show larger grain sizes as the annealing temperature is increased. The X-ray diffraction patterns show that the films are polycrystalline and also evidence the formation of ZnO at temperatures as low as 200°C.