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Öğe The Impact of Dopant on the Dielectric Properties of Metal-Semiconductor With ZnFe2O4 Doped Organic Polymer Nanocomposites Interlayer(Ieee-Inst Electrical Electronics Engineers Inc, 2022) Alsmael, Jaafar Abdulkareem Mustafa; Tan, Serhat Orkun; Tecimer, Habibe Uslu; Altindal, Semsettin; Kalandaragh, Yashar AzizianIn this research, the dielectric characteristics of fabricated Al/(ZnFe2O4-PVA)/p-Si structures have been investigated in wide range frequency and voltage. Thus, by deriving capacitance-conductance (C-G/omega) measurements the main parameters of the metal-polymer-semiconductor (MPS) structure such as complex dielectric constants (epsilon ' and epsilon ''), loss tangent (tan delta), complex electric modulus (M ' and M '') and ac electrical conductivity (sigma(ac)), were acquired at frequency and voltage ranges of 1 kHz-1 MHz and (+/- 5V). As a result of the experiment, it was observed that the presence of negative capacitance (NC) at low frequencies differently affects the dielectric properties of the structure. Although the NC effect disappeared at high frequencies by the reduction of the effect of many parameters such as series resistance (R-ss) and interface states (N-ss) with frequency increment, the dielectric properties of the structure varied especially in the reverse bias region. Ultimately, it has been observed that the dielectric properties of the structure are highly dependent on frequency, voltage, N-ss, and polarization.Öğe Impedance response and phase angle determination of metal-semiconductor structure with n-doped diamond like carbon interlayer(2024) Urgun, Nuray; Vahıd, Aylar Feızollahı; Alsmael, Jaafar Abdulkareem Mustafa; Avar, Barış; Tan, Serhat OrkunWith their superior properties over p-n barriers, Schottky Barrier Diodes have a wide usage area, especially as a test tool to produce better-performance devices. The main performance parameter of these devices is measured by their conduction, which can develop with an interlayer addition through the sandwich design. Regarding the DLC, which also has outstanding specifications under thermal, chemical, and physical conditions, is a good candidate for interlayer tailoring, specifically when used with doping atoms. Thus, this study investigates the impedance response of the fabricated device with an N-doped DLC interlayer by employing the electrochemical technique as a combination of electrolysis, RF magnetron sputtering, and thermal evaporation. The measurements were conducted for broad scales of voltage and frequency corresponding between (-3V) and (+4V) and 1kHz and 1MHz, respectively. According to the impedance analysis, complex impedance decreases by rising bias and frequency, from 1.8 M? to 2 k ? at 1MHZ due to the additional insulating layer. At the same time, the phase angle indicates the quality of the dielectric layer with an average of 81.36 ? for the sample logarithmic frequency values with an almost constant-like trend in the inversion stage. In comparison, it reduces to an average of 30.25 ? after the depletion stage by showing the rising conductivity. Moreover, it has some unexpected rising values at the strong accumulation stage, possibly due to the deposited thin film's unique structure. The supported results by phase angle changes, showing frequency-adjustable working conditions, may offer that selective electrical conduction can be tuned.Öğe An informetric view to the negative capacitance phenomenon at interlayered metal-semiconductor structures and distinct electronic devices(2023) Urgun, Nuray; Alsmael, Jaafar Abdulkareem Mustafa; Tan, Serhat OrkunNegative Capacitance (NC) phenomenon, which can be explained as the material exhibiting an inductive behavior, is often referred to as \"anomalous\" or \"abnormal\" in the literature. Especially in the forward bias/deposition region, the presence of surface states (Nss) and their relaxation times (?), series resistance (Rs), minority carrier injection, interface charge loss in occupied states under the Fermi energy level, parasitic inductance, or poor measuring equipment calibration problems can be counted among the causes of this phenomenon. Studies on NC behavior have shown that this behavior can be observed for different frequencies, temperatures, and related parameters at forward biases. However, the NC behavior, which appears as an unidentified peak in admittance spectroscopy data, is not yet fully understood. Ultimately, this study aims to compile and analyze the NC reported in selected scientific studies, investigate the source of this phenomenon, and observe statistics in a general view.Öğe Investigation of Negative Capacitance in Admittance Analysis of Metal Semiconductors Interlayered With ZnFe2O4 Doped PVA(Ieee-Inst Electrical Electronics Engineers Inc, 2024) Alsmael, Jaafar Abdulkareem Mustafa; Tan, Serhat OrkunIn this work, Al/p-Si structures with (ZnFe2O4- PVA) interfacial film, which is grown by the electrospinning-method, have been analyzed by using impedance measurements in the wide frequency interval (2 kHz-2 MHz) at both side of polarization (+/- 4 V). Some fundamental important electrical parameters such as intercept-voltage (V-o), the concentration of acceptor-atoms (N-A), depletion layer width (W-d), and barrier-height (phi(B)) were extracted from intercept and slope of the 1/C-2 vs V plot in the inversion region for each frequency. It has been observed that parameters such as the presence of surface states (N-SS), relaxation or lifetimes (tau), organic interlayer, dipoles or surface polarization in the inversion and depletion regions, especially at low and moderate frequencies, are obviously dependent on the frequency and applied biases. The voltage and frequency dependence profile of the series resistor (R-S), N-SS,N- and also tau were determined from the Nicollian-Brews method and Nicollian-Goetzberger conductance technique, respectively. The magnitude of N-SS and the values of tau were calculated from the maximum value of (G(P)/omega) related to the frequency for different voltage values. The negative capacitance (NC) at about zero biases and the source of the two incongruous peaks in the depletion and accumulation zones were also discussed. While the first peak in the depletion region was a result of N-SS, the second peak in the depletion region was caused by the effect of R-S.Öğe PREPARATION OF AL/p-Si STRUCTURES WITH ZnFe2O4 DOPED PVA INTERLAYER AND INVESTIGATION OF ELECTRICAL AND DIELECTRIC PROPERTIES IN WIDE RANGE OF FREQUENCY AND VOLTAGE(2023-05) Alsmael, Jaafar Abdulkareem MustafaIn this study, it is aimed to reveal the reliability and performance of the organic interlayered metal-semiconductor (MS) structures and its electronic components by investigating the electrical, dielectric and admittance chararacteristics. In this context, instead of using traditional dielectric/interlayer structures at MS interface, ZnFe2O4-PVA is preferred as an interlayer. For this reason, many studies have been performed including various electrical, dielectric and input parameters. Al/p-Si structures with ZnFe2O4-PVA interlayer prepared by electrospinning method were investigated by using capacitance and conductance (C&G/?) data in a wide frequency range of 0.5kHz-3000kHz and voltage range of ±4V. The voltage dependent C&G/? data of Al/(ZnFe2O4-PVA)/p-Si structure was compared and analyzed at low and high frequencies such as 10kHz and 1000kHz. It is noted that in the resulting capacitance-? voltage (C-V) curves, a peak in the negative direction is observed, which can be categorized as negative capacitance (NC) behavior. NC is a phenomenon that occurs at relatively lower frequencies and is mostly produced by injection of minority carriers, surface states (NSS), and series resistance (RS). Due to the different values of the relaxation times (?) and the NSS distribution, the NC behaves differently at low and high frequencies and loses its activity with increasing frequency. The NSS distribution, which affects the electrical properties, was acquired by using three methods as admittance method, high/low frequency method, and Hill/Coleman method. In the admittance method, NSS and ? values were calculated from the maximum value of the parallel conductance (GP/?) corresponding to the frequency for different voltages. In addition, the Nicollian/Brews method was used to calculate the RS values. Corrected capacitance (CC) and corrected conductance (GC/?) graphs were created to eliminate the RS effect. C?2-V graphs were used at the inverse bias to determine the barrier height (?B), Fermi energy level (EF), concentration of doped acceptor atoms (NA), depletion layer width (Wd), and maximum electric field (Em) in the range of 40-1000 kHz. In order to reveal the dielectric properties, complex dielectric constants (?', ?''), complex electric modulus (?', ?""), tangent loss (tan?), AC electrical conductivity (?ac) and impedance values (?*) were investigated in the ranges of 0.5kHz-3000kHz and ±4.0 V. Consequently, especially at low and moderate frequencies, such parameters as, NSS, polymer interlayer, dipoles or surface polarization affect the electrical and admittance parameters of the structure depending on the applied biases. In addition, dielectric parameters are considerably dependent on frequency and polarization, and its NC behavior at low frequencies reveals that the structure has extraordinary dielectric properties.
