28 research outputs found
Analysis of density and time constant of interface states of MIS device by conductance method
No full textThe 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 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
Impedance spectroscopy of Au/TiO2/n-Si metal-insulator-semiconductor (MIS) capacitor
No full textIn this study, the electrical properties of Au/TiO2/n-Si metal-insulator-semiconductor (MIS) capacitor were investigated by impedance spectroscopy (IS) technique. Impedance measurements were performed in the frequency range of 10 Hz-1 MHz for various bias voltages. The Cole-Cole plots show a single dielectric relaxation. The equivalent circuit was estimated from the shape of the Cole-Cole plots. The equivalent circuit of the MIS capacitor consists of a parallel resistor (R-p) and capacitor (C-p) in series with a resistor (R-s). It is observed that the Cole-Cole plots indicate a semicircle. The parameters of the equivalent circuit were determined by fitting the impedance measurement data. While the R-p value decreases with increasing the bias voltage, the C-p and R-s value are almost independent of the bias voltage. From the variation of log(R-p) with log(V), the dominant conduction mechanism of the MIS capacitor was determined as space-charge limited current (SCLC) mechanism
Electrical characterization of silicon nitride interlayer-based MIS diode
No full textIn this study, silicon nitride (Si3N4) thin film on p-type GaAs wafer was deposited by RF magnetron sputtering. The surface morphology of Si3N4/GaAs structure was analyzed by atomic force microscopy (AFM). The electrical characteristics of the fabricated Au/Si3N4/p-GaAs metal-insulator-semiconductor (MIS) diode were investigated by using current-voltage (I-V) measurements at room temperature. The electronic parameters such as ideality factor (n) and barrier height (phi(bo)) of the MIS diode were derived using thermionic emission (TE). The phi(bo) was also extracted from Norde method. The barrier height values obtained from both TE and Norde were found to be in harmony with each other. The interface state density (N-ss) and series resistance (R-s) parameters of the MIS diode were determined from the measured I-V data. In addition, the dominant current conduction mechanisms of the MIS diode were also investigated by forward bias ln(I-F) - ln(V-F) and reverse bias ln(I-R) - V-R(0.5) plot. At high forward bias, the current conduction was associated with the space charge limited current (SCLC). At reverse bias region, the current conduction was associated with the Schottky emission (SE)
Illumination Response of Impedance Properties of Al/Gr-PVA/p-Si (MPS) Device
No full textAdmittance measurements including capacitance (C) and conductance (G) of Al/Gr-PVA/p-Si (MPS) device were made at 500 kHz and under dark and 200 mW/cm2 conditions. The illumination response on the electric characteristics of the device was investigated using the C-2-V characteristics. It was observed that the electronic parameters of the device changed depending on the illumination conditions. The doping concentration, Fermi energy and barrier height were obtained using the C-2-V data. The surface state (Nss) was also obtained using capacitance data. The results show that the device can be used as a photocapacitor
Electrical and photoresponse properties of CoSO4-PVP interlayer based MPS diodes
No full text© 2020, Springer Science+Business Media, LLC, part of Springer Nature.The cobalt sulfate-polyvinylpyrrolidone (CoSO4-PVP) solution was deposited on n-Si crystal by using spin-coated method. The electrical and photoresponse properties of Au/(CoSO4-PVP)/n-Si MPS diode were investigated both in the dark and under illumination (100 mW/cm2) level. MPS-type diode exhibits good rectifying behavior in dark condition. The measured reverse current under illumination was found to be higher than dark condition. The MPS diode has also a good response to the illumination and photosensitivity value was found as 5.25 × 103 for 100 mW/cm2. The diode parameters such as n, Φb0 and Rs were extracted based on both the thermionic-emission (TE) and Norde method. The current conduction mechanisms of the MPS diode were also analyzed by forward ln(IF)-ln(VF) and reverse ln(IR)-VR1/2 plots. Moreover, both the voltage dependence of C and G characteristics were investigated under 1 MHz. The other electrical parameters such as V0, VD, ND, EF, WD and ΦB were extracted from the C−2–V characteristics. Besides, the voltage dependence profile of the Nss was extracted by using dark-illumination capacitance (Cdark-Cill) measurements at a frequency of 1 MHz. The results suggest that the prepared Au/(CoSO4-PVP)/n-Si MPS diode can be used in optoelectronic device applications
Analysis of surface states and series resistance in Au/n-Si Schottky diodes with insulator layer using current-voltage and admittance-voltage characteristics
No full textTataroglu, Adem/0000-0003-2074-574XWOS: 000272057200001In order to good interpret the experimentally observed Au/n-Si (metal-semiconductor) Schottky diodes with thin insulator layer (18 angstrom) parameters such as the zero-bias barrier height (Phi(bo)), ideality factor (n), series resistance (R-s) and surface states have been investigated using current-voltage (I-V), capacitance-frequency (C-f) and conductance-frequency (G-f) techniques. The forward and reverse bias I-V characteristics of Au/n-Si (MS) Schottky diode were measured at room temperature. In addition, C-f and G-f characteristics were measured in the frequency range of 1 kHz-1 MHz. The higher values of C and G at low frequencies were attributed to the insulator layer and surface states. Under intermediate forward bias, the semi-logarithmic Ln (I)-V plot shows a good linear region. From this region, the slope and the intercept of this plot on the current axis allow to determine the ideality factor (n). the zero-barrier height (Phi(bo)) and the saturation current (I-s) evaluated to 2.878, 0.652 and 3.61 x 10(-7) A, respectively. The diode shows non-ideal I-V behavior with ideality factor greater than unity. This behavior can be attributed to the interfacial insulator layer, the surface states, series resistance and the formation barrier inhomogeneity at metal-semiconductor interface. From the C-f and G-f characteristics, the energy distribution of surface states (N-ss) and their relaxation time (tau) have been determined in the energy range of (E-c-0.493E(v))-(E-c-0.610) eV taking into account the forward bias I-V data. The values of N-ss and tau change from 9.35 x 10(13) eV(-1) cm(-2) to 2.73 x 10(13) eV(-1) cm(-2) and 1.75 x 10(-5) s to 4.50 x 10(-4) s, respectively. (C) 2009 Elsevier Ltd. All rights reserved.Gazi University Scientific Research Project (BAB)Gazi University [FEF 05/2009-34, FEF 05/ 2009-56]This work is supported by Gazi University Scientific Research Project (BAB), FEF-Research Project FEF 05/2009-34 and FEF 05/ 2009-56
Analysis of dielectric, impedance and electrical properties of interfacial layer: AlN
No full textThe purpose of this study is to investigate the electric and dielectric properties of Au/Ti/AlN/n-Si device with using admittance measurements. Aluminum nitride (AlN) epitaxial template on n-Si substrate was deposited by a hydride vapor phase epitaxy (HVPE) technique. Au/Ti contact was thermally evaporated on AlN thin film. Thus, admittance measurements (Y = G + iωC) of the fabricated device were performed and analyzed for frequencies ranging from 1 to 1000 kHz and at room temperature. The C–V and G/ω–V characteristics shown a strong frequency dependence. This behavior is related to the interface traps changing with applied ac signal. In addition, the dielectric parameters, conductivity, and electric modulus of the device were extracted from capacitance and conductance data. The obtained results suggest that the prepared device can be used as a capacitor in electronic circuits
Dielectric, Conductivity and Modulus Properties of Au/ZnO/p-InP (MOS) Capacitor
No full textDielectric, conductivity and modulus properties of MOS capacitor with zinc oxide (ZnO) interlayer produced via RF magnetron sputtering were investigated by using admittance spectroscopy measurements. Frequency and temperature dependence of the complex dielectric permittivity (epsilon* = epsilon '-i epsilon ''), dielectric loss factor (tan delta), ac conductivity (sigma (ac)) and complex electric modulus (M*=M"+iM') were studied in temperature interval of 100-400 K for two frequencies (100 kHz and 500 kHz). While the dielectric constant (epsilon ') and loss (epsilon ') value increase as the temperature rises, their values decrease as the frequency rises. The increase in epsilon ' and epsilon ' is explained by thermal activation of charge carriers. Also, the sigma (ac) value increases both frequency and temperature increase. The thermal activation energy (E-a) were determined from slope of Arrhenius plot
Photoresponse characteristics of Au/(CoFe2O4-PVP)/n-Si/Au (MPS) diode
No full textPhotoresponse characteristics of the Au/(CoFe2O4-PVP)/n-Si (MPS) diode were investigated using current-voltage (I-V) measurements achieved under dark and various illumination conditions. The experimental results showed that the MPS diode has a good response to the illumination. Especially, in reverse bias region, photocurrent (I-ph) increases with increasing illumination intensity (P) due to the formation of electron-hole pairs. The double-logarithmic I-ph-P plot has a good relation with 1.27 slope and such high value of slope indicates a lower density of the unoccupied trap level. This indicates that the diode exhibits a good photoconductive and photovoltaic behavior. The photo-to-dark current ratio confirms the photosensitivity of the diode. Thermionic emission (TE) theory was used to determine the diode electronic parameters such as saturation current (I-0), ideality factor (n) and barrier height (phi(B0)) and their values were calculated from the measured I-V data. Moreover, the phi(B0) and series resistance (R-s) were extracted from an alternative method suggested by Norde. All these parameters (phi(B0), n, R-s, and I-0) decrease with increasing illumination intensity and there is a good linear correlation between phi(B0) and n as phi(B0) (n) = 4.72 x 10(-2)n + 0.5464 eV. As a result, the fabricated MPS diode due to the excellent photoresponse can be used for photovoltaic applications
Ionizing radiation effects on Au/TiO2/n-Si metal-insulator-semiconductor (MIS) structure
No full textThis paper presents the ionizing radiation effects on current-voltage (I-V) characteristics of Au/TiO2/n-Si metal-insulator-semiconductor (MIS) structure. The TiO(2)film as the dielectric interface layer of Au/n-Si was deposited using RF magnetron sputtering method. The MIS structure was exposed to gamma irradiation from Co-60 source with the dose rate of 0.69 kGy/h, and it was irradiated in the range of 0-100 kGy. The electronic parameters such as barrier height (phi(b0)), ideality factor (n), series resistance (R-s), and interface state density (N-ss) of the MIS structure were calculated from the measured I-V data. Experimental results showed that all calculated parameters change with the irradiation dose rate. To determine current conduction mechanisms of the MIS structure, the In (I-F) vs In (V) and In (I-R) vsV(1/2)curves for all irradiation doses are plotted under both forward bias and reverse bias, respectively
