The density of interface states and their relaxation times in Au/Bi4Ti3O12/SiO2/n-Si(MFIS) structures

Bulbul M. M., Altindal Ş., Parlakturk F., TATAROĞLU A.

SURFACE AND INTERFACE ANALYSIS, vol.43, no.13, pp.1561-1565, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 43 Issue: 13
  • Publication Date: 2011
  • Doi Number: 10.1002/sia.3749
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1561-1565
  • Keywords: MFIS structure, admittance measurements, frequency dependence, interface states, relaxation time, DEPENDENT SERIES RESISTANCE, SI-SIO2 INTERFACE, CAPACITANCE MEASUREMENTS, THIN-FILMS, DIODES, PROFILE
  • Gazi University Affiliated: Yes


Bismuth titanate (Bi4Ti3O12) (BTO) thin films were fabricated on an n-type Si substrate and annealed by rapid thermal annealing methods. The I-V measurement shows that the device has properties of Schottky diode with the Phi(B0) of 0.76 eV, n of 2.42, and leakage current of about 10(-7) A at -8 V. The experimental C-V-f and G/w-V-f characteristics of metal-ferroelectric-insulator-semiconductor (MFIS) structures show fairly large frequency dispersion especially at low frequencies due to interface states N-ss. The energy distribution of (N-ss) has been determined by using the high-low frequency capacitance (C-HF-C-LF) and conductance method. The relaxation time (tau) of interface states was calculated from the conductance method. It has been shown that both the N-ss and relaxation time increase almost exponentially with bias, which activates traps located at deeper gap energies. Copyright (C) 2011 John Wiley & Sons, Ltd.