A Second-Order ΣΔ ADC with 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)


The capability of new technologies, such as oxide thin-film transistors (TFTs) is reinforced when they are successfully integrated in circuits or systems with a considerable level of complexity. In the particular case of this study, sputtered indium-gallium-zinc oxide (IGZO) TFTs are used to design, simulate and produce an analog-to-digital converter (ADC), demonstrating the potential of this technology namely in terms of lower processing temperature and costs and excellent performance, typically far superior to a-Si and organics and comparable to LTPS.

In this chapter, the optimized IGZO TFTs with multilayer and multicomponent dielectric, based on Ta2O5 and SiO2, are used to design a sigma-delta (\( \Sigma \Delta \)) modulator (\( \Sigma \Delta M \)), with a particular attention to the comparator, the active block in the circuit. The circuits are simulated using commercial electronic design automation (EDA) tools, which will be briefly referred. Furthermore, some layout considerations and hints for a successful fabrication are also provided.


Print Circuit Board Electrical Simulation Wire Bonding Process Electronic Design Automation Oxide TFTs 
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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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