Interface trap characterization and electrical properties of Au-ZnO nanorod Schottky diodes by conductance and capacitance methods

Abstract

Schottky diodes with Au/ZnO nanorod (NR)/n-SiC configurations have been fabricated and their interface traps and electrical properties have been investigated by current-voltage (I-V), capacitance-voltage (C-V), capacitance-frequency (C-f), and conductance-frequency (G p /x-x) measurements. Detailed and systematic analysis of the frequency-dependent capacitance and conductance measurements was performed to extract the information about the interface trap states. The discrepancy between the high barrier height values obtained from the I-V and the C-V measurements was also analyzed. The higher capacitance at low frequencies was attributed to excess capacitance as a result of interface states in equilibrium in the ZnO that can follow the alternating current signal. The energy of the interface states (E ss ) with respect to the valence band at the ZnO NR surface was also calculated. The densities of interface states obtained from the conductance and capacitance methods agreed well with each other and this confirm that the observed capacitance and conductance are caused by the same physical processes, i.e., recombination-generation in the interface states. V C 2012 American Institute of Physics.

Analysis of junction properties of gold–zinc oxide nanorods-based Schottky diode by means of frequency dependent electrical characterization on textile

“…In figure (4 and the ideality factor were found to be 0.61 eV and 2.34 respectively. These are the average values in agreement with other published works [26][27][28][29][35][36][37][38]. Following fundamental equations of a Schottky diode were used for the calculation of electrical parameters.…”

“…This trapping occurred due to the high R effects on carrier flow between the metal and semiconductor or it can be caused due to the surface roughness or lattice mismatch at the interface of metal-semiconductor [22][23][24]. Usually, in n-type ZnO a large amount of electrons tends to diffuse away to reach the interface layer but trapped by the trapping states by a positive ionized donor charges in the neighborhood of interface of metal-ZnO nanorods [23][24][25][26][27][28].Therefore a large amount of charges moved along the metal and semiconductor interfaces, so trapping states occurred in the interface layers due to the various metal-oxides addition [23][24][25].…”

Temperature-dependent current–voltage characteristics of Pd/ZnO Schottky barrier diodes and the determination of the Richardson constant

“…Several researchers have studied current transport properties of Schottky contacts at room temperature in which a thermionic emission (TE) model has been used to calculate the diode parameters [9,10]. In these calculations, it was assumed that TE is the dominant current transport mechanism.…”

Systematic study of interface trap and barrier inhomogeneities using I-V-T characteristics of Au/ZnO nanorods Schottky diode

“…[3][4][5][6] The realization of high quality Schottky contacts on ZnO nanostructures seems to be difficult because of the interface states, the surface morphology, hydroxide surface contamination, and the subsurface defects, which all play important roles in the electrical properties of these contacts. 7 In recent years, a number of process methodologies have been developed for the fabrication of reproducible high quality Schottky contacts on ZnO nanostructures, but controversies remain with regard to the Schottky barrier height and the factor of the ZnO Schottky contacts. 7,8 The deviations in the barrier heights and the ideality factor have been proposed as having been caused by the effects of asymmetric contacts, and the influence of the interfacial layers and/or surface states.…”