Current Transport Mechanism of n-Type Nanocrystalline FeSi2/Intrinsic Si/p-Type Si Heterojunctions Fabricated by Facing-Targets Direct-Current Sputtering

n-Type nanocrystalline FeSi2/intrinsic Si/p-type Si heterojunctions were successfully fabricated by FTDCS and their forward current-voltage characteristics at low temperatures were analyzed on the basis of thermionic emission theory. The analysis of J-V characteristics exhibits an increase in the ideality factor and a decrease in the barrier height at low temperatures. The values of ideality factor were estimated to be 2.26 at 300 K and 9.29 at 77 K. The temperature dependent ideality factortogether with the constant value of parameter A indicated that a trap assisted multi-step tunneling process is the dominant carrier transport mechanism in this heterojunction. At high voltages, the current transport mechanism is dominated by SCLC process.

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Electrical Characteristics of n-Type Nanocrystalline FeSi2/Intrinsic Si/p-Type Si Heterojunctions Prepared by Facing-Targets Direct-Current Sputtering

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.446-447.88 ◽

2013 ◽

Vol 446-447 ◽

pp. 88-92

Author(s):

Nathaporn Promros ◽

Suguru Funasaki ◽

Ryūhei Iwasaki ◽

Tsuyoshi Yoshitake

Keyword(s):

Barrier Height ◽

Ideality Factor ◽

Low Temperatures ◽

Series Resistance ◽

Linear Part ◽

Thermionic Emission ◽

Straight Line ◽

Current Voltage ◽

P Type ◽

Direct Current Sputtering

n-Type nanocrystalline FeSi2/intrinsic Si/p-type Si heterojunctions were prepared by FTDCS. In order to estimate their diode parameters such as ideality factor, barrier height and series resistance, their current-voltage characteristics were measured in the temperature range from 300 to 77 K and analyzed on the basis of thermionic emission theory and Cheungs method. Based on thermionic emission theory, the ideality factor was calculated from the slope of the linear part from the forward lnJ-V characteristics. The barrier height was calculated once the saturation current density was derived from the straight line intercept of lnJ-V plot at a zero voltage. The obtained results exhibit an increase of ideality factor and a decrease of barrier height at low temperatures, which might be owing to inhomogeneity of material and non-uniformity of charge at the interface. Based on Cheungs method, the ideality factor and barrier height were estimated from y-axis intercept of dV/d (lnJ)J plot and y-axis intercept of H(J)J plot, respectively. The series resistance was analyzed from the slopes of dV/d (lnJ)J and H(J)J plots. The values of ideality factor and barrier height obtained from this method are in agreement with those obtained from the thermionic emission theory. The obtained series resistances from dV/d (lnJ)J and H(J)J plots, which were approximately equal to each others, were increased as the temperature decreased. This result should be owing to the increased ideality factor and remarkably reduced carrier concentrations at low temperatures.

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Mechanism of Carrier Transport in n-Type β-FeSi2/Intrinsic Si/p-Type Si Heterojunctions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1119.189 ◽

2015 ◽

Vol 1119 ◽

pp. 189-193

Author(s):

Nathaporn Promros ◽

Motoki Takahara ◽

Ryuji Baba ◽

Tarek M. Mostafa ◽

Mahmoud Shaban ◽

...

Keyword(s):

Ideality Factor ◽

Carrier Transport ◽

Linear Part ◽

Forward Bias ◽

Thermionic Emission ◽

Forward Bias Voltage ◽

Space Charge Limit ◽

Current Voltage ◽

P Type ◽

Direct Current Sputtering

Preparation of n-type β-FeSi2/intrinsic Si/p-type Si heterojunctions was accomplished by facing-target direct-current sputtering (FTDCS) and measuring their current-voltage characteristic curves at low temperatures ranging from 300 K down to 50 K. A mechanism of carrier transport in the fabricated heterojunctions was investigated based on thermionic emission theory. According to this theory, the ideality factor was calculated from the slope of the linear part of the forward lnJ-V plot. The ideality factor was 1.12 at 300 K and increased to 1.99 at 225 K. The estimated ideality factor implied that a recombination process was the predominant mechanism of carrier transport. When the temperatures decreased below 225 K, the ideality factor was estimated to be higher than two and parameter A was estimated to be constant. The obtained results implied that the mechanism of carrier transport was governed by a trap-assisted multi-step tunneling process. At high forward bias voltage, the predominant mechanism of carrier transport was changed into a space charge limit current process.

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Diode Parameters of Heterojunctions Comprising p-Type Si Substrate and n-Type β-FeSi2 Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1043.57 ◽

2014 ◽

Vol 1043 ◽

pp. 57-61

Author(s):

Nathaporn Promros ◽

Suguru Funasaki ◽

Motoki Takahara ◽

Mahmoud Shaban ◽

Tsuyoshi Yoshitake

Keyword(s):

Current Density ◽

Ideality Factor ◽

Linear Part ◽

Thermionic Emission ◽

Saturation Current ◽

Straight Line ◽

Current Voltage ◽

Saturation Current Density ◽

P Type ◽

Direct Current Sputtering

n-Type β-FeSi2/p-type Si heterojunctions have been successfully fabricated by facing-targets direct-current sputtering at a substrate temperature of 600 °C without post-annealing and their current-voltage characteristics were measured at low temperatures ragne from 300 K down to 50 K. The ideality factor, saturation current and series resistance were estimated by the thermionic emission theory and Cheung’s method. By the thermionic emission theory, we calculated the ideality factor from the slope of the linear part from the forward lnJ-V and estimated the saturation current density from the straight line intercept of lnJ-V at a zero voltage. As decreasing temperatures from 300 down to 50 K, the value of ideality factor increased from 1.2 to 15.6, while the value of saturation current density decreased from 1.6 × 10−6 A/cm2 to 3.8 × 10−10 A/cm2. From the plots of dV/d (lnJ)-J and H(J)-J by Cheung’s method, the obtained values of series resistances are consistent with each other. The series resistances analyzed from both plots increased as decreasing temperatures.

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Diode Parameters of Mesa Structural n-Type Nanocrystalline FeSi2/p-Type Si Heterojunctions Prepared by Lift-Off Photolithography

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1103.91 ◽

2015 ◽

Vol 1103 ◽

pp. 91-96

Author(s):

Nathaporn Promros ◽

Suguru Funasaki ◽

Motoki Takahara ◽

Ryūhei Iwasaki ◽

Mahmoud Shaban ◽

...

Keyword(s):

Barrier Height ◽

Ideality Factor ◽

Low Temperatures ◽

Series Resistance ◽

Thermionic Emission ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Lift Off ◽

P Type ◽

Photolithography Process

Mesa structural n-type nanocrystalline-FeSi2/p-type Si heterojunctions were successfully fabricated by a lift-off technique combined with a photolithography process. Their current-voltage characteristics were measured at low temperatures range from 300 K down to 60 K. We estimated their diode parameters such as ideality factor, barrier height and series resistance based on the thermionic emission theory and Cheung’s method. From the estimation by the thermionic emission theory, the obtained results show an increase of ideality factor and a decrease of barrier height at low temperatures. The estimation by Cheung’s method shows that the values of ideality factor and barrier height are in agreement with those obtained from the thermionic emission theory. The obtained series resistances from dV/d (lnJ)-J and H(J)-J plots, which are approximately equal to each others, are increased at low temperatures.

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A Current Transport Mechanism on the Surface of Pd-SiO2Mixture for Metal-Semiconductor-Metal GaAs Diodes

Advances in Materials Science and Engineering ◽

10.1155/2013/531573 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4

Author(s):

Shih-Wei Tan ◽

Shih-Wen Lai

Keyword(s):

Transport Mechanism ◽

Carrier Transport ◽

Schottky Contact ◽

Thermionic Emission ◽

Image Force ◽

Current Transport ◽

Current Transport Mechanism ◽

Carrier Recombination ◽

Metal Semiconductor Metal ◽

A Current

This paper presents a current transport mechanism of Pd metal-semiconductor-metal (MSM) GaAs diodes with a Schottky contact material formed by intentionally mixing SiO2into a Pd metal. The Schottky emission process, where the thermionic emission both over the metal-semiconductor barrier and over the insulator-semiconductor barrier is considered on the carrier transport of a mixed contact of Pd and SiO2(MMO) MSM diodes, is analyzed. The image-force lowering is accounted for. In addition, with the applied voltage increased, the carrier recombination is thus considered. The simulation data are presented to explain the experimental results clearly.

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Temperature Dependent Current-Voltage Characteristics of n-Type Nanocrystalline-FeSi2/p-Type Si Heterojunctions Fabricated by Pulsed Laser Deposition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.858.171 ◽

2013 ◽

Vol 858 ◽

pp. 171-176

Author(s):

Nathaporn Promros ◽

Ryūhei Iwasaki ◽

Suguru Funasaki ◽

Kyohei Yamashita ◽

Chen Li ◽

...

Keyword(s):

Barrier Height ◽

Ideality Factor ◽

Carrier Transport ◽

Series Resistance ◽

Thermionic Emission ◽

Temperature Dependent ◽

Zero Bias ◽

Current Voltage ◽

Current Voltage Characteristics ◽

P Type

n-Type NC-FeSi2/p-type Si heterojunctions were successfully fabricated by PLD, and their forward current-voltage characteristics were analyzed on the basis of thermionic emission theory (TE) in the temperature range from 300 down to 77 K. With a decrease in the temperature, the ideality factor was increased while the zero-bias barrier height was decreased. The calculated values of ideality factor and barrier height were 3.07 and 0.63 eV at 300 K and 10.75 and 0.23 eV at 77 K. The large value of ideality factor indicated that a tunneling process contributes to the carrier transport mechanisms in the NC-FeSi2 films. The series resistance, which was estimated by Cheungs method, was strongly dependent on temperature. At 300 K, the value of series resistance was 12.44 Ω and it was dramatically enhanced to be 1.71× 105 Ω at 77 K.

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Investigation of carrier transport mechanisms in the Cu–Zn–Se based hetero-structure grown by sputtering technique

Canadian Journal of Physics ◽

10.1139/cjp-2017-0777 ◽

2018 ◽

Vol 96 (7) ◽

pp. 816-825 ◽

Cited By ~ 8

Author(s):

H.H. Güllü ◽

M. Terlemezoğlu ◽

Ö. Bayraklı ◽

D.E. Yıldız ◽

M. Parlak

Keyword(s):

Barrier Height ◽

Carrier Transport ◽

Thermionic Emission ◽

Electrical Characterization ◽

Band Gap Energy ◽

Zero Bias ◽

Hetero Structure ◽

Current Voltage ◽

P Type

In this paper, we present results of the electrical characterization of n-Si/p-Cu–Zn–Se hetero-structure. Sputtered film was found in Se-rich behavior with tetragonal polycrystalline nature along with (112) preferred orientation. The band gap energy for direct optical transitions was obtained as 2.65 eV. The results of the conductivity measurements indicated p-type behavior and carrier transport mechanism was modelled according to thermionic emission theory. Detailed electrical characterization of this structure was carried out with the help of temperature-dependent current–voltage measurements in the temperature range of 220–360 K, room temperature, and frequency-dependent capacitance–voltage and conductance-voltage measurements. The anomaly in current–voltage characteristics was related to barrier height inhomogeneity at the interface and modified by the assumption of Gaussian distribution of barrier height, in which mean barrier height and standard deviation at zero bias were found as 2.11 and 0.24 eV, respectively. Moreover, Richardson constant value was determined as 141.95 Acm−2K−2 by means of modified Richardson plot.

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Current-transport mechanism in Au/V-doped PVC+TCNQ/p-Si structures

International Journal of Modern Physics B ◽

10.1142/s0217979215500769 ◽

2015 ◽

Vol 29 (13) ◽

pp. 1550076 ◽

Cited By ~ 3

Author(s):

H. Tecimer ◽

Ö. Vural ◽

A. Kaya ◽

Ş. Altındal

Keyword(s):

Temperature Coefficient ◽

Transport Mechanism ◽

Forward Bias ◽

Thermionic Emission ◽

Negative Temperature ◽

Positive Temperature ◽

Current Transport ◽

Insulator Layer ◽

Zero Bias ◽

Current Transport Mechanism

The forward and reverse bias current–voltage (I–V) characteristics of Au/V-doped polyvinyl chloride+Tetracyanoquino dimethane/porous silicon (PVC+TCNQ/p-Si) structures have been investigated in the temperature range of 160–340 K. The zero bias or apparent barrier height (BH) (Φ ap = Φ Bo ) and ideality factor (n ap = n) were found strongly temperature dependent and the value of n ap decreases, while the Φ ap increases with the increasing temperature. Also, the Φ ap versus T plot shows almost a straight line which has positive temperature coefficient and it is not in agreement with the negative temperature coefficient of ideal diode or forbidden bandgap of Si (α Si = -4.73×10-4 eV/K ). The high value of n cannot be explained only with respect to interfacial insulator layer and interface traps. In order to explain such behavior of Φ ap and n ap with temperature, Φ ap Versus q/2kT plot was drawn and the mean value of (Φ Bo ) and standard deviation (σs) values found from the slope and intercept of this plot as 1.176 eV and 0.152 V, respectively. Thus, the modified ( ln (Io/T2)-(qσs)2/2(kT)2 versus (q/kT) plot gives the Φ Bo and effective Richardson constant A* as 1.115 eV and 31.94 A ⋅(cm⋅K)-2, respectively. This value of A*( = 31.94 A⋅( cm ⋅K)-2) is very close to the theoretical value of 32 A ⋅(cm⋅K)-2 for p-Si. Therefore, the forward bias I–V–T characteristics confirmed that the current-transport mechanism (CTM) in Au/V-doped PVC+TCNQ/p-Si structures can be successfully explained in terms of the thermionic emission (TE) mechanism with a Gaussian distribution (GD) of BHs at around mean BH.

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