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Journal of Display Technology

Journal of Display Technology


  • Vol. 9, Iss. 9 — Sep. 1, 2013
  • pp: 723–728

Plastic Compatible Sputtered ${{Ta}}_{2}{{O}}_{5}$ Sensitive Layer for Oxide Semiconductor TFT Sensors

Rita Branquinho, Joana V. Pinto, Tito Busani, Pedro Barquinha, Luis Pereira, Pedro Viana Baptista, Rodrigo Martins, and Elvira Fortunato

Journal of Display Technology, Vol. 9, Issue 9, pp. 723-728 (2013)

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The effect of post-deposition annealing temperature on the pH sensitivity of room temperature RF sputtered ${{Ta}}_{2}{{O}}_{5}$ was investigated. Structural and morphological features of these films were analyzed before and after annealing at various temperatures. The deposited films are amorphous up to 600 $^{\circ}{{C}}$ and crystallize at 700 $^{\circ}{{C}}$ in an orthorhombic phase. Electrolyte-insulator-semiconductor (EIS) field effect based sensors with an amorphous ${{Ta}}_{2}{{O}}_{5}$ sensing layer showed pH sensitivity above 50 mV/pH. For sensors annealed above 200 $^{\circ}{{C}}$ pH sensitivity decreased with increasing temperature. Stabilized sensor response and maximum pH sensitivity was achieved after low temperature annealing at 200 $^{\circ}{{C}}$ , which is compatible with the use of polymeric substrates and application as sensitive layer in oxides TFT-based sensors.

© 2012 IEEE

Rita Branquinho, Joana V. Pinto, Tito Busani, Pedro Barquinha, Luis Pereira, Pedro Viana Baptista, Rodrigo Martins, and Elvira Fortunato, "Plastic Compatible Sputtered ${{Ta}}_{2}{{O}}_{5}$ Sensitive Layer for Oxide Semiconductor TFT Sensors," J. Display Technol. 9, 723-728 (2013)

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  1. P. Bergveld, "Development of an ion-sensitive solid-state device for neurophysiological measurements," IEEE Trans. Biomed. Eng. BME-17, 70-71 (1970).
  2. P. Bergveld, "Thirty years of ISFETOLOGY: What happened in the past 30 years and what may happen in the next 30 years," Sensors and Actuators B: Chem. 88, 1-20 (2003).
  3. D. E. Yates, S. Levine, T. W. Healy, "Site-binding model of the electrical double layer at the oxide/water interface," J. Chem. Soc. Faraday Trans. 1: Physical Chemistry in Condensed Phases 70, 1807-1818 (1974).
  4. R. E. G. van Hal, J. C. T. Eijkel, P. Bergveld, "A general model to describe the electrostatic potential at electrolyte oxide interfaces," Adv. Colloid and Interface Sci. 69, 31-62 (1996).
  5. M. J. Schoning, A. Poghossian, "Bio FEDs (field-effect devices): state-of-the-art and new directions," Electroanal. 18, 1893-1900 (2006).
  6. D. Gonçalves, D. M. F. Prazeres, V. Chu, J. P. Conde, "Detection of DNA and proteins using amorphous silicon ion-sensitive thin-film field effect transistors," Biosensors Bioelectron. 24, 545-551 (2008).
  7. T.-W. Lin, D. Kekuda, C.-W. Chu, "Label-free detection of DNA using novel organic-based electrolyte-insulator-semiconductor," Biosensors Bioelectron. 25, 2706-2710 (2010).
  8. N. Ozer, C. Lampert, "Structural and optical properties of sol-gel deposited proton conducting ${\hbox{Ta}}_{2}{\hbox{O}}_{5}$ films," J. Sol-Gel Sci. Technol. 8, 703-709 (1997).
  9. P. D. Batista, M. Mulato, "ZnO extended-gate field-effect transistors as pH sensors," Appl. Phys. Lett. 87, (2005).
  10. A. Poghossian, M. H. Abouzar, F. Amberger, D. Mayer, Y. Han, S. Ingebrandt, A. Offenhäusser, M. J. Schöning, "Field-effect sensors with charged macromolecules: Characterisation by capacitance-voltage, constant-capacitance, impedance spectroscopy and atomic-force microscopy methods," Biosensors Bioelectron. 22, 2100-2107 (2007).
  11. L. Pereira, P. Barquinha, E. Fortunato, R. Martins, D. Kang, C. J. Kim, H. Lim, I. Song, Y. Park, "High k dielectrics for low temperature electronics," Thin Solid Films 516, 1544-1548 (2008).
  12. M. Spijkman, E. C. P. Smits, J. F. M. Cillessen, F. Biscarini, P. W. M. Blom, D. M. de Leeuw, "Beyond the Nernst-limit with dual-gate ZnO ion-sensitive field-effect transistors," Appl. Phys. Lett. 98, 043502-043503 (2011).
  13. J. V. Pinto, R. Branquinho, P. Barquinha, E. Alves, R. Martins, E. Fortunato, "Extended-gate ISFETs based on sputtered amorphous oxides," J. Display Technol. .
  14. L. Pereira, H. Águas, E. Fortunato, R. Martins, "Nanostructure characterization of high- $k$ materials by spectroscopic ellipsometry," Appl. Surf. Sci. 253, 339-343 (2006).
  15. E. Franke, M. Schubert, C. L. Trimble, M. J. DeVries, J. A. Woollam, "Optical properties of amorphous and polycrystalline tantalum oxide thin films measured by spectroscopic ellipsometry from 0.03 to 8.5 eV," Thin Solid Films 388, 283-289 (2001).
  16. N. P. Barradas, C. Jeynes, R. P. Webb, "Simulated annealing analysis of Rutherford backscattering data," Appl. Phys. Lett. 71, 291-293 (1997).
  17. C. Chaneliere, J. L. Autran, R. A. B. Devine, B. Balland, "Tantalum pentoxide (Ta2O5) thin films for advanced dielectric applications," Mater. Sci. Eng. : R: Rep. 22, 269-322 (1998).
  18. T.-M. Pan, J.-C. Lin, M.-H. Wu, C.-S. Lai, "Study of high-k Er2O3 thin layers as ISFET sensitive insulator surface for pH detection," Sensors and Act. B: Chem. 138, 619-624 (2009).
  19. H. Barhoumi, A. Maaref, N. Jaffrezic-Renault, "Experimental study of thermodynamic surface characteristics and pH sensitivity of silicon dioxide and silicon nitride," Langmuir 26, 7165-7173 (2010).
  20. R. Branquinho, B. Veigas, J. V. Pinto, R. Martins, E. Fortunato, P. V. Baptista, "Real-time monitoring of PCR amplification of proto-oncogene c-MYC using a ${\hbox{Ta}}_{2}{\hbox{O}}_{5}$ electrolyte–insulator–semiconductor sensor," Biosensors Bioelectron. 28, 44-49 (2011).

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