An evaluation of structural, optical and electrical characteristics of Ag/ZnO rods/SnO2/In-Ga Schottky diode


KÜÇÜKÖMEROĞLU T., YILMAZ S., POLAT İ., BACAKSIZ E.

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS, vol.29, no.12, pp.10054-10060, 2018 (SCI-Expanded) identifier identifier

Abstract

ZnO rods were successfully deposited on ZnO seeded SnO2 coated glass substrates by a spray pyrolysis route. It was seen that the grown ZnO sample had a wurtzite structure with a well-defined hexagons of similar to 1-3 A mu m in diameter. Photoluminescence results measured at 300 K indicated that ZnO rods had a ultra-violet peak located at 383 nm without a deep level band emission. ZnO rods were subsequently used to realize a Ag/ZnO rods/SnO2/In-Ga Schottky diode which displayed rectifying current-voltage (I-V) characteristic with a turn on voltage of 1.2 V at 300 K. Electrical parameters of the Ag/ZnO rods/SnO2/In-Ga Schottky diode were further examined by (I-V) characteristics at the temperature range of 125-300 K with a step of 25 K. Using thermionic emission theory (TET), it was found that the ideality factor reduced with the increase of temperature whereas the zero bias barrier height increased with the increment of the temperature. Using ln(I (0) )/T (2) versus q/nkT plot, Richardson constant (A*) and zero bias barrier height (I broken vertical bar (B0)) was obtained as 3.27 x 10(-5) A m(-2) K-2 and 0.32 eV, respectively. After applying TET with the assumption of Gaussian distribution, a mean barrier height and the modified Richardson constant (A**) were determined to be 0.88 eV and 2.75 x 10(5) A m(-2) K-2.