On the profile of temperature and voltage dependence of interface states and resistivity in Au/n-Si structure with 79 angstrom insulator layer thickness

Yildirim M., Eroglu A., Altindal Ş., Durmus P.

JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS, cilt.13, ss.98-105, 2011 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 13
  • Basım Tarihi: 2011
  • Dergi Adı: JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.98-105
  • Anahtar Kelimeler: MS structure with insulator layer, Temperature dependent barrier height, Voltage dependent resistance, Interface states, Anomalous peak in C-V plots, SCHOTTKY-BARRIER DIODES, C-V CHARACTERISTICS, HIGH SERIES RESISTANCE, SURFACE-STATES, IV PLOT, FREQUENCY, CAPACITANCE, EXTRACTION, SILICON, PARAMETERS
  • Gazi Üniversitesi Adresli: Evet

Özet

In this study, the temperature and voltage dependence of interface states (N-ss) and resistance profile of Au/n-Si structure with 79 angstrom insulator layer thickness were obtained from the forward and reverse bias capacitance-voltage (C-V) and conductance-voltage (G/omega-V) measurements in the temperature range of 80-400 K at 1 MHz. The main electrical parameters, such as doping concentration (N-D), Fermi energy level (E-F), depletion layer width (W-D) and barrier height (phi(CV)), of these structures were also determined from the reverse bias C-2 vs V plots in the same range. The values of phi(CV) at the absolute temperature (T=0 K) and the temperature coefficient (alpha) of barrier height were found as 1.152 eV and -2.4x10(-4) eV/K, respectively. These values are in a close agreement with the bandgap value of Si at 0 K (E-g=1.17 eV) and its temperature coefficient value (-4.73x10(4) eV/K). C-V plots for all temperature levels show an anomalous peak in the accumulation region because of the effect of series resistance (Rs). Similarly, G/omega-V plots also show a peak in the depletion region between the temperature range of 160-320 K. The effect of R-s on the C and G is found noticeable especially at high temperatures. Therefore, the measured C and G values were corrected in order to eliminate the effect of R-s using Nicollian and Brews method. In addition, the temperature dependent ac conductivity (sigma(ac)) data obtained between 200 and 400 K show a linear behavior and was fitted to the Arrhenius plot. The values of activation energy (E-a) obtained from the slope In square-q/kT plots are 21.7, 18.5, 15.0 and 11.5 meV for the values of applied biases 3.5, 4.0, 4.5 and 5.0 V, respectively.