Effect of Co-60 gamma-ray irradiation on electrical properties of Ti/Au/GaAs1-xNx Schottky diodes

Current-voltage (I-V), capacitance-voltage-frequency (C-V-f) and conductance-voltage-frequency (G/ω-V-f) measurements at room temperature are used to study 50 kGy 60Co γ-ray electrical properties irradiation dependence of Ti/Au/GaAs1−xNx Schottky diodes with 0.2%; 0.4%; 0.8% and 1.2% nitrogen dilution. This γ-ray irradiation induces a permanent damage that has increased ideality factor and series resistance for all samples. It was accompanied by a decrease in Schottky barrier height with nitrogen content up to 0.4%N and remained constant thereafter. Radiation was also found to degrade the reverse leakage current. At high frequency (1 MHz), capacitance and conductance decreased after radiation due to a decrease in net doping concentration. Interface state density and series resistance were determined from C-V-f and G/ω-V-f characteristics using Hill-Coleman methods. Interface states density exponentially decreased with increasing frequency confirming the behavior of interface traps response to ac signal. Series resistance increases after irradiation is attributed to carrier's removal effect and mobility degradation. It has two peaks in the accumulation and inversion region for some diodes (0.4%N, 0.8%N). γ-ray irradiation produced traps levels and recombination centers that reduce relaxation time. An increase in %N content can impede irradiation damage with even some compensation when the percent of diluted nitrogen is high (1.2%N)

SiC polytypes and doping nature effects on electrical properties of ZnO-SiC Schottky diodes

Electrical properties of ZnO/SiC Schottky diodes with two SiC polytypes and N and P doping are investigated. Characterization was performed through I–V and C–V–f measurements. Schottky barrier height (Φb), ideality factor (n), and series resistance (Rs) were extracted from forward I–V characteristics. (Φb), carrier’s concentrations (Nd-Na) and (Rs) frequency dependence were extracted from C–V–f characteristics. The extracted n values suggest that current transport is dominated by interface generation-recombination and/or barrier tunneling mechanisms. When changing SiC polytypes, the rectifying ratio of ZnO/n-4HSiC is found to be twice that of ZnO/n-6HSiC. A change in doping nature gave a leakage current ratio of 40 between ZnO/p-4HSiC and ZnO/n- 4HSiC. These results indicate that ZnO/p-4HSiC diodes have a complex current transport compared to diodes on n-type SiC. From I-V measurements, barrier height values are 0.63eV, 0.65eV and 0.71 eV for heterojunction grown on n-6HSiC, n-4HSiC and p-4HSiC, respectively. C-V measurements gave higher values indicating the importance of interface density of states. Nss values at 1MHz frequency are 4.54×1011 eV-1 cm-2, 3×1012 eV-1 cm-2 and 8.13×1010 eV-1 cm-2 for ZnO/n-6HSiC, ZnO/n-4HSiC and ZnO/p-4HSiC, respectively. Results indicate the importance of SiC polytypes and its doping natur

Analysis of density and time constant of interface states of MIS device by conductance method

374-378<span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">The density and time constant of interface states of Au/Si3N4/n-Si (MIS) device have been analyzed by conductance method. The capacitance and conductance measurements of the device have been performed at various frequencies in the range of 1 kHz-1 MHz. Experimental results show that Gp/ω-log(f) plots for each voltage value give <span style="font-size: 11.0pt;mso-bidi-font-size:10.0pt;font-family:" times="" new="" roman","serif";="" mso-fareast-font-family:mtsy;mso-ansi-language:en-us;mso-fareast-language:en-us;="" mso-bidi-language:ar-sa"="" lang="EN-US">a peak because of the presence of interface states. The density (Nss) and time constant () of interface states have been calculated from maximum value of the peak. The values of Nss and range from 2.49×1013 eV-1cm-2 to 7.57×1012 eV-1cm-2 and from 2.67×10-5s to 1.67×10-5s, respectively.</span

Electrical characterization of MIS diode prepared by magnetron sputtering

142-148TiO2 thin film has been prepared on n-type Si wafer to fabricate an Au/TiO2/n-Si (MIS) diode by RF magnetron sputtering technique. The current-voltage (I-V) and capacitance-voltage (C-V) measurements of the diode have been performed over a wide range of temperatures (240-400 K) and frequencies (10 kHz-1 MHz), respectively. From I-V measurements, an abnormal increase in the barrier height (Φb) and a decrease in the ideality factor (n) with increasing temperature have been observed. This temperature dependence has been attributed to the barrier in homogeneities by assuming a Gaussian distribution (GD) of barrier heights at metal/semiconductor (M/S) interface. Both the conventional and modified Richardson plot show linearity. The activation energy (Ea), Richardson constant (A*) and Φb value have been calculated from the slope and intercept of the linear region. The obtained Richardson constant value of 113.82 A. cm-2. K-2 is in close agreement with the known value of 112 A.cm-2. K-2 for n-Si. The interface state density (Nss) and series resistance (Rs) of the diode has been obtained from the I-V measurements. In addition, the Φb value was determined from C-2-V characteristics. The obtained results indicate that the MIS diode with TiO2 interfacial insulator layer can be used in many device applications

A comparative study on the electrical and dielectric properties of Al/Cd-doped ZnO/p-Si structures

WOS: 000475587800030We have reported on the electrical and dielectric properties of Al/CdxZn1-xO/p-Si structures. The cadmium-doped zinc oxide (CdxZn1-xO) thin films with various Cd dopants (x=0.10, 0.20 and 0.30) were deposited on p-Si wafers via sol-gel spin coating method. The admittance (Y=G(m)+i omega C-m) measurements were performed at 1MHz. The C-2-V plots were used to extract the main electrical parameters such as the diffusion potential (V-D), the concentration of acceptor atoms (N-A), depletion region width (W-D) and barrier height (Phi(B)). The experimental results reveal that the capacitance increases with higher Cd dopant concentration due to the presence of interfacial charges while an opposite behaviour is observed in conductance. The lower values of conductance in the sample with high Cd content can be attributed to increase in series resistance. The dielectric measurements also confirm the effect of Cd substitution in ZnO on the device performance

Boron doped graphene based linear dynamic range photodiode

The boron-doped graphene oxide film was prepared using drop casting/coating technique. The film was coated by hydrothermal method on p-Si substrate and thus Al/p-Si/B-doped GO/Au diode was fabricated. The structural properties of the film was investigated by SEM and EDS techniques. The optoelectronic behavior of the diode was analyzed under various solar light and frequencies. The diode indicates that the forward current is higher that of reverse current with a rectification ratio (RR = I-F/I-R) of 7.30 x 10(4) at dark and +/- 5 V. The diode electronic parameters of the diode were computed from electrical characteristics. An increase in the photocurrent of the diode with solar light intensity indicates the presence of a photoconduction mechanism. The photoconductive and photovoltaic response of the diode were analyzed using photocurrent measurements. The interface state density (N-ss) of the diode was analyzed from conductance technique. The optoelectrical results of the studied device suggest that the diode can be used in optic communications.Scientific Project Unit of Kirklareli University [Klubap 76, Klubap 113]; International Scientific Partnership Program ISPP at King Saud University [0046]This study was supported by Scientific Project Unit of Kirklareli University under project number: Klubap 113. This study was supported by Scientific Project Unit of Kirklareli University under project number: Klubap 76. The authors extend their appreciation to the International Scientific Partnership Program ISPP at King Saud University for funding this research work through ISPP# 0046.WOS:0004496211000142-s2.0-8504813680