Synthesis and characterization of pure and graphene (Gr)-doped organic/polymer nanocomposites to investigate the electrical and photoconductivity properties of Au/n-GaAs structures


Cicek O., Tecimer H. U. , Tan S. O. , Tecimer H., Orak I., Altindal Ş.

COMPOSITES PART B-ENGINEERING, cilt.113, ss.14-23, 2017 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 113
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1016/j.compositesb.2017.01.012
  • Dergi Adı: COMPOSITES PART B-ENGINEERING
  • Sayfa Sayıları: ss.14-23

Özet

In the present study, Schottky diodes (SDs) were produced with and without interlayer to evaluate synthesis and characterization of pure and graphene (Gr)-doped organic/polymer nanocomposites on the electrical (i.e. ideality factor (n), saturation current (I-o), barrier height (Phi(Bo)), shunt (R-sh) and series (R-s) resistances) and photoconductivity (i.e. photocurrent (I-ph), responsivity (R), photoconductivity sensitivity (S-ph), photosensitivity) parameters of Au/n-GaAs devices. Electrical parameters of Au/n-GaAs (MS) type (D-1), Au/pure PVA/n-GaAs (MPS) type (D-2) and Au/Gr-doped PVA/n-GaAs (MPS) type (D-3) structures have been obtained to the current-voltage (I-V) measurements using thermionic emission (TE) theory, Cheung's method and modified Norde's methods and, moreover, compared each other. The resistance (R-i) for these SDs was additionally calculated from Ohm's law as function of voltage for each diode. Experimental research indicate that there is an increase in R-sh value and a decrease in R-s value and rectifier rate (RR = I-F/I-R) for Gr-doped PVA structure according to the pure PVA structure, when the values of R-s and R-sh are compared between each other. Also, the Phi(Bo) values for D-2 and D-3 type SDs is lower than that of D-1 type SDs. The value of R-s for Gr-PVA interlayer 286 times lower than without interlayer. Therefore, it can be said that the PVA (pure and Gr-doped) interfacial layer effectively modified the barrier height (BH) according to without interlayer. As photoconductivity properties for SDs, the I-ph values in the reverse bias increased with illumination intensities (50-200 W). On the other hand, it is clear that there are an increase for D-2 and D-3 and a decrease for D1 with increasing illumination intensities in the R and S-ph values. So, they are sensitive to illumination intensities and exhibit a photoconductivity effect. As a result, Gr-doped PVA interlayer substantially got better the quality and performance of Au/PVA/n-GaAs SDs. (C) 2017 Elsevier Ltd. All rights reserved.