Oxide TFTs @ FCT-UNL

  • Ana Paula Pinto Correia
  • Pedro Miguel Cândido Barquinha
  • João Carlos da Palma Goes
Part of the SpringerBriefs in Electrical and Computer Engineering book series (BRIEFSELECTRIC)


Oxide thin-film transistors (TFTs) optimization is imperative in order to obtain a successful integration of circuits. In fact, parameters as turn-on voltage (Von) or gate leakage current (IG) are known to influence circuit characteristics. These parameters are greatly affected by the properties of the dielectric layer and its interface with the semiconductor. Therefore, amorphous high-κ dielectrics acquire an important role, especially in multicomponent single or multilayer structures, where materials with different electrical properties (e.g., high-κ and high bandgap energy, EG) are combined to acquire dielectrics with the best possible performance and reliability.

In this chapter a brief overview about fabrication of thin films and TFTs is provided. Then, it presents a detailed discussion on the characterization of sputtered amorphous multicomponent high-κ dielectrics based on Ta2O5 and SiO2, using single and multilayer structures, and their integration in indium-gallium-zinc oxide (IGZO) TFTs. Finally, an existing model for a-Si:H TFTs is adapted to IGZO TFTs technology.


Atomic Force Microscopy Multilayer Structure Rutherford Backscattering Spectroscopy Substrate Bias Spectroscopic Ellipsometry 
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Copyright information

© The Author(s) 2016

Authors and Affiliations

  • Ana Paula Pinto Correia
    • 1
  • Pedro Miguel Cândido Barquinha
    • 2
  • João Carlos da Palma Goes
    • 1
  1. 1.CTS/UNINOVA and Department of Electrical EngineeringUniversidade NOVA de LisboaLisbonPortugal
  2. 2.I3N/CENIMAT and Department of Materials ScienceUniversidade NOVA de LisboaLisbonPortugal

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