Sol-gel derived n-type Zn(1-x)MgxO (x = 0-0.45) thin films and thin-film transistors (TFTs) with active channel layers made of the films were investigated. The films were prepared at 500°C. The effects of Mg doping on the crystallinity, optical transparency, grain size, and charge-carrier concentration (n) of the films were examined. The Fermi level of the films, as derived from the temperature dependence of n, was ∼0.12 eV below the conduction band. The donor concentration and donor level (E d) were derived by a curve fitting method based on the electrical neutrality condition. Ed was found to be ∼0.3 eV below the conduction band. The composition dependence of the TFT output characteristics was interpreted and correlated to the width of the depletion region adjacent to the grain boundaries. When the grains were almost depleted at x = 0.2, the TFT showed an enhancement mode and an on/off ratio of 106.
|Number of pages||6|
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Issue number||7 A|
|Publication status||Published - 2005 Jul 8|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)