The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Ru Sun - One of the best experts on this subject based on the ideXlab platform.
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rosamine with Pyronine pyridinium skeleton unique mitochondrial targetable structure for fluorescent probes
Analyst, 2018Co-Authors: Ling Yang, Jinyun Niu, Ru SunAbstract:Two rosamine-based probes (1a–b) with Pyronine-pyridinium skeleton were designed and prepared. Probe 1a bearing boron ester unit was oxidized and eliminated upon addition of hydrogen peroxide (H2O2), and the emission spectrum exhibited OFF–ON response accompanied by 33-fold fluorescent enhancement. In contrast, the fluorescence intensity of probe 1b enhanced 58 times after the dinitrophenyl ether part within the probe was removed by nucleophilic substitution with hydrosulfide (H2S). The design concept was based on the d-PET process in Pyronine-pyridinium structures, and free 4-pyridinyl-substituted Pyronine dye showing strong fluorescence was released followed by elimination. Furthermore, as biocompatible molecules, probes 1a–b have been successfully applied for imaging in live HeLa and Ges-1 cells, and all of them can serve as mitochondrial targetable probes in red channel for detecting independent species.
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the application of mitochondrial targetable Pyronine pyridinium skeleton in the detection of nitroreductase
Sensors and Actuators B-chemical, 2018Co-Authors: Ling Yang, Jinyun Niu, Ru SunAbstract:Abstract In this paper, a new compound ( 3 ) with Pyronine-pyridine skeleton had a strong fluorescence at pH 5.0−9.0, while the emission turned off at pH = 1.0–2.0. It was a mitochondrial biomarker in cancer cells (KB, 4T1, HeLa) and normal cells (Ges-1, L929, WS1). Based on these above results, probe 1 with Pyronine-pyridinium skeleton was further designed and prepared to detect nitroreductase (NTR). The nitrofuran group of probe 1 was reduced and eliminated upon addition of NTR and nicotinamide adenine dinucleotide (NADH) to produce compound 3 , and the d-PET process could be allowed in the Pyronine-pyridinium structure of probe 1 but it was prohibited in the Pyronine-pyridine skeleton of compound 3 after detection, hence probe 1 showed a nearly turn-on signal in red light region at 565–800 nm with emission maxima at 604 nm. The detection limit was calculated as low as 2.2 ng/mL. Furthermore, fluorescence imaging experiments with live HeLa and Ges-1 cells were performed, and probe 1 could serve as a mitochondrial targetable probe to detect nitroreductase in red channel.
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the ph influenced pet processes between Pyronine and different heterocycles
Organic and Biomolecular Chemistry, 2017Co-Authors: Ling Yang, Jinyun Niu, Ru SunAbstract:The OFF–ON and ON–OFF type pH probes based on rosamine were designed by using the relative electron densities between Pyronine and various linked heterocycles. Probe 1a with an indole–Pyronine skeleton gave an OFF–ON pH response (pKa = 1.41) with decreasing pH, and the relative fluorescence intensity increased 15-fold, while probe 1b with an imidazole–Pyronine skeleton did not give an ON–OFF response to different pH values. When Pyronine was connected with a quinolinyl group, i.e., probes 1c–d, the red emission (around 575–800 nm) gave a monotonous ON–OFF pH response (pKa = 3.26 and 2.62, respectively) with decreasing pH. The relative fluorescence intensities decreased 263- and 46-fold, respectively. Changes in the electron donating abilities of the nitrogen containing heterocycles were used to explain variations in PET processes within the probes, and their pH-dependent PET mechanisms were verified using time-dependent density functional theory calculations. Confocal fluorescence imaging was also used to evaluate the potential biomedical application of probes 1a–d. Ultimately, probe 1d with an appropriate pKa value and good biocompatibility showed lysosome targeting ability.
Yavuz Onganer - One of the best experts on this subject based on the ideXlab platform.
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pyronin y basic xanthene dye bentonite composite a spectroscopic study
Journal of Molecular Structure, 2014Co-Authors: Ahmet Tabak, Mehmet Kaya, N Yilmaz, Kadem Meral, Yavuz Onganer, Bulent Caglar, O SungurAbstract:Abstract The expansion by 1.43 Angstrom of basal spacing and the shift to higher frequencies of in-plane ring vibrations of the Pyronin Y molecule at 1603 and 1527 cm −1 on the formation of Pyronin Y-bentonite composite exhibited that the dye cations might be oriented as a monolayer form in the interlamellar spacing with aromatic rings parallel to clay layers. Thermal analysis results of this composite compared to those of raw bentonite signified the different outer sphere water entities associated with the replacement of inorganic cations with organic dye cations and the gradual decomposition of the organic molecule in the interlamellar spacing. Thermo-Infrared spectra of Pyronin Y-bentonite sample up to high temperatures showed the thermal stability of the dye–clay composite as a result of the presence of π interactions. The pore structure characteristics of Pyronin Y-bentonite composite exhibited the increase in the number of mesopores during formation of the composite.
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electrical characteristics of au Pyronine b moderately doped n type inp schottky structures in a wide temperature range
Journal of Alloys and Compounds, 2011Co-Authors: M Soylu, B Abay, Yavuz OnganerAbstract:Abstract The temperature dependence of current–voltage ( I – V ) characteristics of the Au/Pyronine-B/moderately doped (MD) n-InP Schottky barrier diode has been systematically investigated in the temperature range of 160–400 K. Modification of the interfacial potential barrier for metal/InP diodes has been achieved using a thin interlayer of the Pyronine B organic semiconductor. It has been observed that ideality factor n (=1.10) remained close to ideal limit while barrier height of Au/Pyronine-B/n-InP structure increased about 0.180 eV with respect to Au/n-InP in the previous study, at room temperature. The forward I – V characteristics have been interpreted on the basis of standard thermionic emission (TE) theory and assumption of a Gaussian distribution of the barrier height. The apparent barrier height and the ideality factor derived by using thermionic emission theory have been found to be strongly temperature dependent. That is, it has been understood that the ideality factor decreases while the apparent barrier height ( Φ b 0 j ) increases with increasing temperature. It has been shown that the conventional ln( J 0 / T 2 ) vs. 1000/ T plot exhibits a non-linearity below 240 K. It has been demonstrated that this behaviour results due to the barrier height inhomogeneities prevailing at the metal–semiconductor interface. The mean barrier height ( Φ ¯ b j ) and the Richardson constant ( A *) values were obtained as 0.961 eV and 17.73 A K −2 cm −2 , respectively, by means of the modified Richardson plot, [ ln ( J 0 / T 2 ) − ( q 2 σ 0 2 / 2 k 2 T 2 ) ] vs. 1/ T . The value of Richardson constant A * obtained from this plot is close to the theoretical value of 9.4 A K −2 cm −2 for n-InP. As a result, it can be concluded that the temperature dependent characteristic parameters for Au/Pyronine-B/MD n-InP structure can be succesfully explained on the basis of TE mechanism with Gaussian distribution of the barrier height.
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the effects of annealing on au Pyronine b md n inp schottky structure
Journal of Physics and Chemistry of Solids, 2010Co-Authors: M Soylu, B Abay, Yavuz OnganerAbstract:Abstract Thin film of non-polymeric organic compound Pyronine-B has been fabricated on moderately doped (MD) n-InP substrate as an interfacial layer using spin coating technique for the electronic modification of Au/MD n-InP Schottky contact. The electrical characteristics have been determined at room temperature. The barrier height and the ideality factor values for Au/Pyronine-B/MD n-InP Schottky diode have been obtained from the forward bias I – V characteristics at room temperature as 0.60 eV and 1.041; 0.571 and 1.253 eV after annealing at 100 and 250 °C, respectively. An increase in annealing temperature at the Au/n-InP Schottky junction is shown to increase the reverse bias leakage current by about one order of magnitude and decrease the Schottky barrier height by 0.027 eV. Furthermore, the barrier height values for the Au/Pyronine-B/MD n-InP Schottky diode have also been obtained from the C – V characteristics at room temperature as 1.001 and 0.709 eV after annealing at 100 and 250 °C, respectively. Finally, it was seen that the diode parameters changed with increase in the annealing temperature.
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rectifying Pyronine b p type silicon junctions formed by sublimation of Pyronine b
Journal of Materials Science: Materials in Electronics, 2004Co-Authors: M Cakar, A Turut, Yavuz OnganerAbstract:The rectifying junction characteristics of the organic compound Pyronine-B film on a p-type Si substrate have been studied. The Pyronine-B has been sublimed onto the top of p-Si surface. The barrier height and ideality factor values of 0.79 eV and 1.125 for this structure have been obtained from the forward-bias current–voltage characteristics. The density distribution of the interface states in the inorganic semiconductor bandgap and their relaxation time have been determined from the low-capacitance–frequency characteristics by the Schottky capacitance spectroscopy method. The measurement frequency varies from 90 Hz to 10 MHz. The interface state density Nss ranges from 2.10×1010 cm−2 eV−1 in (0.79−Ev) eV to 1.16×1012 cm−2 eV−1 in (0.53−Ev) eV. Furthermore, the relaxation time ranges from 1.38×10−3 s in (0.53−FV) eV to 7.50×10−3 s in (0.79−EV) eV.
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the conductance and capacitance frequency characteristics of the rectifying junctions formed by sublimation of organic Pyronine b on p type silicon
Journal of Solid State Chemistry, 2002Co-Authors: M Cakar, A Turut, Yavuz OnganerAbstract:Abstract The rectifying junction characteristics of the organic compound Pyronine-B film on a p-type Si substrate has been studied. The Pyronine-B has been sublimed on the top of p-Si surface. The barrier height and ideality factor values of 0.79±0.04 and 1.13±0.06 eV for this structure have been obtained from the forward bias current–voltage ( I – V ) characteristics. From the low capacitance-frequency ( C–f ) characteristics as well as conductance–frequency ( G–f ) characteristics, the energy distribution of the interface states and their relaxation time have been determined in the energy range of (0.53− E v )–(0.79− E v ) eV taking into account the forward bias I – V data. The interface state density N ss ranges from 4.93×10 10 cm −2 eV −1 in (0.79− E v ) eV to 3.67×10 13 cm −2 eV −1 in (0.53− E v ) eV. Furthermore, the relaxation ranges from 3.80×10 −3 s in (0.53− E v ) eV to 4.21×10 −4 s in (0.79− E v ) eV. It has been seen that the interface state density has an exponential rise with bias from the midgap towards the top of the valence band. The relaxation time shows a slow exponential rise with bias from the top of the valence band towards the midgap.
A Turut - One of the best experts on this subject based on the ideXlab platform.
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the schottky barrier height of the rectifying cu Pyronine b p si au Pyronine b p si sn Pyronine b p si and al Pyronine b p si contacts
Synthetic Metals, 2004Co-Authors: M Cakar, Cabir Temirci, A TurutAbstract:Abstract The Cu/Pyronine-B/p-Si, Au/Pyronine-B/p-Si, Al/Pyronine-B/p-Si and Sn/Pyronine-B/p-Si Schottky structures have been obtained by sublimation of the organic compound Pyronine-B onto the top of p-Si surface. Our goal is to experimentally investigate whether or not a nonpolymeric organic compound as contact to an inorganic semiconductor such as Si can provide the continuous control of the barrier height (BH). The barrier height Φ bp values of 0.51, 0.674, 0.75 and 0.79 eV for the Cu/Pyronine-B/p-Si, Au/Pyronine-B/p-Si, Al/Pyronine-B/p-Si and Sn/Pyronine-B/p-Si Schottky structures have obtained from the forward current–voltage ( I – V ) characteristics. It has been seen that the values of Φ bp are significantly larger than those of conventional Schottky diodes.
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rectifying Pyronine b p type silicon junctions formed by sublimation of Pyronine b
Journal of Materials Science: Materials in Electronics, 2004Co-Authors: M Cakar, A Turut, Yavuz OnganerAbstract:The rectifying junction characteristics of the organic compound Pyronine-B film on a p-type Si substrate have been studied. The Pyronine-B has been sublimed onto the top of p-Si surface. The barrier height and ideality factor values of 0.79 eV and 1.125 for this structure have been obtained from the forward-bias current–voltage characteristics. The density distribution of the interface states in the inorganic semiconductor bandgap and their relaxation time have been determined from the low-capacitance–frequency characteristics by the Schottky capacitance spectroscopy method. The measurement frequency varies from 90 Hz to 10 MHz. The interface state density Nss ranges from 2.10×1010 cm−2 eV−1 in (0.79−Ev) eV to 1.16×1012 cm−2 eV−1 in (0.53−Ev) eV. Furthermore, the relaxation time ranges from 1.38×10−3 s in (0.53−FV) eV to 7.50×10−3 s in (0.79−EV) eV.
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the conductance and capacitance frequency characteristics of the organic compound Pyronine b p si structures
Synthetic Metals, 2003Co-Authors: M Cakar, A TurutAbstract:Abstract The nonpolymeric organic compound Pyronine-B thin film on a p-type Si substrate has been formed by the process of adding a solution of Pyronine-B in methanol and evaporating the solvent. It has been seen that the Pyronine-B/p-Si contact shows the rectifying behavior. The barrier height and ideality factor values of 0.65 eV and 1.50, respectively, for this structure have been obtained from the forward bias current–voltage ( I – V ) characteristics. The energy distribution of the interface states and their relaxation time by means of the conductance method and Schottky capacitance spectroscopy (SCS) method have been determined in the energy range from (0.41− E V ) to (0.65− E V ) eV. It has been seen that the interface state density has an exponential rise with bias from the mid-gap towards the top of the valance band. The relaxation time shows a slow exponential rise with bias from the top of the valance band towards the mid-gap. It has been seen that the conductance method in the determination of the energy distribution of the interface states is more appropriate than the SCS method.
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the conductance and capacitance frequency characteristics of the rectifying junctions formed by sublimation of organic Pyronine b on p type silicon
Journal of Solid State Chemistry, 2002Co-Authors: M Cakar, A Turut, Yavuz OnganerAbstract:Abstract The rectifying junction characteristics of the organic compound Pyronine-B film on a p-type Si substrate has been studied. The Pyronine-B has been sublimed on the top of p-Si surface. The barrier height and ideality factor values of 0.79±0.04 and 1.13±0.06 eV for this structure have been obtained from the forward bias current–voltage ( I – V ) characteristics. From the low capacitance-frequency ( C–f ) characteristics as well as conductance–frequency ( G–f ) characteristics, the energy distribution of the interface states and their relaxation time have been determined in the energy range of (0.53− E v )–(0.79− E v ) eV taking into account the forward bias I – V data. The interface state density N ss ranges from 4.93×10 10 cm −2 eV −1 in (0.79− E v ) eV to 3.67×10 13 cm −2 eV −1 in (0.53− E v ) eV. Furthermore, the relaxation ranges from 3.80×10 −3 s in (0.53− E v ) eV to 4.21×10 −4 s in (0.79− E v ) eV. It has been seen that the interface state density has an exponential rise with bias from the midgap towards the top of the valence band. The relaxation time shows a slow exponential rise with bias from the top of the valence band towards the midgap.
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the nonpolymeric organic compound Pyronine b p type silicon sn contact barrier devices
Synthetic Metals, 2002Co-Authors: M Cakar, Yavuz Onganer, A TurutAbstract:Abstract The nonpolymeric organic compound Pyronine-B film on a p-type Si substrate has been formed by means of the process of adding a solution of Pyronine-B in methanol and evaporating the solvent. It has been seen that the Pyronine-B/p-Si contact shows the rectifying behaviour and the reverse curves exhibit the excellent saturation. The barrier height and ideality factor values of 0.65 eV and 1.51, respectively, for this structure have been obtained from the forward bias current–voltage (I–V) characteristics. The energy distribution of the interface states in the inorganic semiconductor bandgap and their relaxation time in the energy range (0.41−Ev) to (0.65−Ev) eV have been determined from the low-capacitance–frequency (C–f) characteristics. The measurement frequency ranges from 50 Hz to 2 MHz. The low and intermediate frequency regions approximately range 50–700 Hz and 700 Hz–500 kHz, respectively. It has been seen that the interface state density has an exponential rise with bias from the midgap towards the top of the valence band. The relaxation time shows a slow exponential rise from the top of the valence band towards the midgap with the applied voltage.
Ling Yang - One of the best experts on this subject based on the ideXlab platform.
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rosamine with Pyronine pyridinium skeleton unique mitochondrial targetable structure for fluorescent probes
Analyst, 2018Co-Authors: Ling Yang, Jinyun Niu, Ru SunAbstract:Two rosamine-based probes (1a–b) with Pyronine-pyridinium skeleton were designed and prepared. Probe 1a bearing boron ester unit was oxidized and eliminated upon addition of hydrogen peroxide (H2O2), and the emission spectrum exhibited OFF–ON response accompanied by 33-fold fluorescent enhancement. In contrast, the fluorescence intensity of probe 1b enhanced 58 times after the dinitrophenyl ether part within the probe was removed by nucleophilic substitution with hydrosulfide (H2S). The design concept was based on the d-PET process in Pyronine-pyridinium structures, and free 4-pyridinyl-substituted Pyronine dye showing strong fluorescence was released followed by elimination. Furthermore, as biocompatible molecules, probes 1a–b have been successfully applied for imaging in live HeLa and Ges-1 cells, and all of them can serve as mitochondrial targetable probes in red channel for detecting independent species.
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the application of mitochondrial targetable Pyronine pyridinium skeleton in the detection of nitroreductase
Sensors and Actuators B-chemical, 2018Co-Authors: Ling Yang, Jinyun Niu, Ru SunAbstract:Abstract In this paper, a new compound ( 3 ) with Pyronine-pyridine skeleton had a strong fluorescence at pH 5.0−9.0, while the emission turned off at pH = 1.0–2.0. It was a mitochondrial biomarker in cancer cells (KB, 4T1, HeLa) and normal cells (Ges-1, L929, WS1). Based on these above results, probe 1 with Pyronine-pyridinium skeleton was further designed and prepared to detect nitroreductase (NTR). The nitrofuran group of probe 1 was reduced and eliminated upon addition of NTR and nicotinamide adenine dinucleotide (NADH) to produce compound 3 , and the d-PET process could be allowed in the Pyronine-pyridinium structure of probe 1 but it was prohibited in the Pyronine-pyridine skeleton of compound 3 after detection, hence probe 1 showed a nearly turn-on signal in red light region at 565–800 nm with emission maxima at 604 nm. The detection limit was calculated as low as 2.2 ng/mL. Furthermore, fluorescence imaging experiments with live HeLa and Ges-1 cells were performed, and probe 1 could serve as a mitochondrial targetable probe to detect nitroreductase in red channel.
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the ph influenced pet processes between Pyronine and different heterocycles
Organic and Biomolecular Chemistry, 2017Co-Authors: Ling Yang, Jinyun Niu, Ru SunAbstract:The OFF–ON and ON–OFF type pH probes based on rosamine were designed by using the relative electron densities between Pyronine and various linked heterocycles. Probe 1a with an indole–Pyronine skeleton gave an OFF–ON pH response (pKa = 1.41) with decreasing pH, and the relative fluorescence intensity increased 15-fold, while probe 1b with an imidazole–Pyronine skeleton did not give an ON–OFF response to different pH values. When Pyronine was connected with a quinolinyl group, i.e., probes 1c–d, the red emission (around 575–800 nm) gave a monotonous ON–OFF pH response (pKa = 3.26 and 2.62, respectively) with decreasing pH. The relative fluorescence intensities decreased 263- and 46-fold, respectively. Changes in the electron donating abilities of the nitrogen containing heterocycles were used to explain variations in PET processes within the probes, and their pH-dependent PET mechanisms were verified using time-dependent density functional theory calculations. Confocal fluorescence imaging was also used to evaluate the potential biomedical application of probes 1a–d. Ultimately, probe 1d with an appropriate pKa value and good biocompatibility showed lysosome targeting ability.
M Cakar - One of the best experts on this subject based on the ideXlab platform.
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the schottky barrier height of the rectifying cu Pyronine b p si au Pyronine b p si sn Pyronine b p si and al Pyronine b p si contacts
Synthetic Metals, 2004Co-Authors: M Cakar, Cabir Temirci, A TurutAbstract:Abstract The Cu/Pyronine-B/p-Si, Au/Pyronine-B/p-Si, Al/Pyronine-B/p-Si and Sn/Pyronine-B/p-Si Schottky structures have been obtained by sublimation of the organic compound Pyronine-B onto the top of p-Si surface. Our goal is to experimentally investigate whether or not a nonpolymeric organic compound as contact to an inorganic semiconductor such as Si can provide the continuous control of the barrier height (BH). The barrier height Φ bp values of 0.51, 0.674, 0.75 and 0.79 eV for the Cu/Pyronine-B/p-Si, Au/Pyronine-B/p-Si, Al/Pyronine-B/p-Si and Sn/Pyronine-B/p-Si Schottky structures have obtained from the forward current–voltage ( I – V ) characteristics. It has been seen that the values of Φ bp are significantly larger than those of conventional Schottky diodes.
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rectifying Pyronine b p type silicon junctions formed by sublimation of Pyronine b
Journal of Materials Science: Materials in Electronics, 2004Co-Authors: M Cakar, A Turut, Yavuz OnganerAbstract:The rectifying junction characteristics of the organic compound Pyronine-B film on a p-type Si substrate have been studied. The Pyronine-B has been sublimed onto the top of p-Si surface. The barrier height and ideality factor values of 0.79 eV and 1.125 for this structure have been obtained from the forward-bias current–voltage characteristics. The density distribution of the interface states in the inorganic semiconductor bandgap and their relaxation time have been determined from the low-capacitance–frequency characteristics by the Schottky capacitance spectroscopy method. The measurement frequency varies from 90 Hz to 10 MHz. The interface state density Nss ranges from 2.10×1010 cm−2 eV−1 in (0.79−Ev) eV to 1.16×1012 cm−2 eV−1 in (0.53−Ev) eV. Furthermore, the relaxation time ranges from 1.38×10−3 s in (0.53−FV) eV to 7.50×10−3 s in (0.79−EV) eV.
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the conductance and capacitance frequency characteristics of the organic compound Pyronine b p si structures
Synthetic Metals, 2003Co-Authors: M Cakar, A TurutAbstract:Abstract The nonpolymeric organic compound Pyronine-B thin film on a p-type Si substrate has been formed by the process of adding a solution of Pyronine-B in methanol and evaporating the solvent. It has been seen that the Pyronine-B/p-Si contact shows the rectifying behavior. The barrier height and ideality factor values of 0.65 eV and 1.50, respectively, for this structure have been obtained from the forward bias current–voltage ( I – V ) characteristics. The energy distribution of the interface states and their relaxation time by means of the conductance method and Schottky capacitance spectroscopy (SCS) method have been determined in the energy range from (0.41− E V ) to (0.65− E V ) eV. It has been seen that the interface state density has an exponential rise with bias from the mid-gap towards the top of the valance band. The relaxation time shows a slow exponential rise with bias from the top of the valance band towards the mid-gap. It has been seen that the conductance method in the determination of the energy distribution of the interface states is more appropriate than the SCS method.
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the conductance and capacitance frequency characteristics of the rectifying junctions formed by sublimation of organic Pyronine b on p type silicon
Journal of Solid State Chemistry, 2002Co-Authors: M Cakar, A Turut, Yavuz OnganerAbstract:Abstract The rectifying junction characteristics of the organic compound Pyronine-B film on a p-type Si substrate has been studied. The Pyronine-B has been sublimed on the top of p-Si surface. The barrier height and ideality factor values of 0.79±0.04 and 1.13±0.06 eV for this structure have been obtained from the forward bias current–voltage ( I – V ) characteristics. From the low capacitance-frequency ( C–f ) characteristics as well as conductance–frequency ( G–f ) characteristics, the energy distribution of the interface states and their relaxation time have been determined in the energy range of (0.53− E v )–(0.79− E v ) eV taking into account the forward bias I – V data. The interface state density N ss ranges from 4.93×10 10 cm −2 eV −1 in (0.79− E v ) eV to 3.67×10 13 cm −2 eV −1 in (0.53− E v ) eV. Furthermore, the relaxation ranges from 3.80×10 −3 s in (0.53− E v ) eV to 4.21×10 −4 s in (0.79− E v ) eV. It has been seen that the interface state density has an exponential rise with bias from the midgap towards the top of the valence band. The relaxation time shows a slow exponential rise with bias from the top of the valence band towards the midgap.
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the nonpolymeric organic compound Pyronine b p type silicon sn contact barrier devices
Synthetic Metals, 2002Co-Authors: M Cakar, Yavuz Onganer, A TurutAbstract:Abstract The nonpolymeric organic compound Pyronine-B film on a p-type Si substrate has been formed by means of the process of adding a solution of Pyronine-B in methanol and evaporating the solvent. It has been seen that the Pyronine-B/p-Si contact shows the rectifying behaviour and the reverse curves exhibit the excellent saturation. The barrier height and ideality factor values of 0.65 eV and 1.51, respectively, for this structure have been obtained from the forward bias current–voltage (I–V) characteristics. The energy distribution of the interface states in the inorganic semiconductor bandgap and their relaxation time in the energy range (0.41−Ev) to (0.65−Ev) eV have been determined from the low-capacitance–frequency (C–f) characteristics. The measurement frequency ranges from 50 Hz to 2 MHz. The low and intermediate frequency regions approximately range 50–700 Hz and 700 Hz–500 kHz, respectively. It has been seen that the interface state density has an exponential rise with bias from the midgap towards the top of the valence band. The relaxation time shows a slow exponential rise from the top of the valence band towards the midgap with the applied voltage.
