Time Dependence of the Reverse Current in Amorphous Silicon Schottky Diodes

1997 ◽  
Vol 467 ◽  
Author(s):  
K. Aflatooni ◽  
R. Hornsey ◽  
A. Nathan
Keyword(s):  
Amorphous Silicon ◽  
Schottky Diodes ◽  
Thermionic Emission ◽  
Reverse Current ◽  
Hole Transport ◽  
Semiconductor Interface ◽  
Present Measurement ◽  
Measurement Results ◽  
Voltage Stress ◽  
Prolonged Stress

ABSTRACTWe present measurement results of the time-dependent reverse current in amorphous silicon Schottky diodes for a broad range of bias voltage stress conditions. The resultant behavior can be divided into three regimes, depending on the bias. At low biases, the reverse current exhibits a power-law dependence attributable to dispersive electron transport. In the medium bias regime, the current shows a dramatic increase which may be due to enhanced thermionic emission and tunneling of electrons across the barrier, enabled by hole transport to the metal-semiconductor interface. At high biases, the effects of prolonged stress were found to be irreversible. Here, an eventual decrease in reverse current was observed, with an associated loss of rectifying characteristics.

Reverse current transient behavior in amorphous silicon Schottky diodes at low biases

1997 ◽  
Vol 70 (24) ◽  
pp. 3260-3262 ◽  
Author(s):  
R. I. Hornsey ◽  
K. Aflatooni ◽  
A. Nathan
Keyword(s):  
Amorphous Silicon ◽  
Schottky Diodes ◽  
Reverse Current ◽  
Transient Behavior ◽  
Current Transient

scholarly journals Current Transport Mechanism in Palladium Schottky Contact on Si-Based Freestanding GaN

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 297
Author(s):  
Moonsang Lee ◽  
Chang Wan Ahn ◽  
Thi Kim Oanh Vu ◽  
Hyun Uk Lee ◽  
Yesul Jeong ◽  
...  
Keyword(s):  
Charge Transport ◽  
Point Defect ◽  
Transport Mechanism ◽  
Deep Level ◽  
Schottky Diodes ◽  
Schottky Contact ◽  
Thermionic Emission ◽  
Reverse Current ◽  
Thermionic Field Emission ◽  
Transient Spectroscopy

In this study, the charge transport mechanism of Pd/Si-based FS-GaN Schottky diodes was investigated. A temperature-dependent current–voltage analysis revealed that the I-V characteristics of the diodes show a good rectifying behavior with a large ratio of 103–105 at the forward to reverse current at ±1 V. The interface states and non-interacting point defect complex between the Pd metal and FS-GaN crystals induced the inhomogeneity of the barrier height and large ideality factors. Furthermore, we revealed that the electronic conduction of the devices prefers the thermionic field emission (TFE) transport, not the thermionic emission (TE) model, over the entire measurement conditions. The investigation on deep level transient spectroscopy (DLTS) suggests that non-interacting point-defect-driven tunneling influences the charge transport. This investigation about charge transport paves the way to achieving next-generation optoelectronic applications using Si-based FS-GaN Schottky diodes.

Mechanism of Current Leakage in Ni Schottky Diodes on Cubic GaN and AlxGa1-xN Epilayers

2005 ◽  
Vol 892 ◽  
Author(s):  
Donat J. As ◽  
Stefan Potthast ◽  
Jara Fernandez ◽  
Klaus Lischka ◽  
Hiroyuki Nagasawa ◽  
...  
Keyword(s):  
Schottky Diodes ◽  
Thermionic Emission ◽  
Surface Barrier ◽  
Free Standing ◽  
Semiconductor Interface ◽  
Doping Density ◽  
Group Iii ◽  
Force Microscopy ◽  
Cubic Gan ◽  
Group Iii Nitride

AbstractNi Schottky-diodes (SDs) 300 μm in diameter were fabricated by thermal evaporation using contact lithography on cubic GaN and AlxGa1-xN epilayers. Phase-pure cubic GaN and c-Al0.3Ga0.7N/GaN structures were grown by plasma assisted molecular beam epitaxy (MBE) on 200 µm thick free-standing 3C-SiC (100) substrates. The quality of the cubic group III-nitride epilayers was checked by high resolution X-ray diffractometry, atomic force microscopy and photoluminescence at room temperature and at 2 K. Large deviations from the thermionic emission transport were observed in the current voltage (I-V) behavior of these SDs. Detailed analysis of the I-V characteristics at 300 K and at low temperature showed that a thin surface barrier is formed at the Ni semiconductor interface. Thermal annealing in air at 200°C alters the composition of this thin surface barrier and reduces the leakage current by three orders of magnitude. The doping density dependence of breakdown voltages derived from the reverse breakdown voltage characteristics of c-GaN SDs is in good agreement with theoretically calculated values and follows the expected trend. From these experimental data a blocking voltage of higher than 600V is extrapolated for c-GaN films with a doping level of ND = 5×1015 cm-3.

Parameter Extraction from the Reverse I-V and C-V Characteristics of an Epitaxial p-InP/Au Schottky Diode

1993 ◽  
Vol 318 ◽  
Author(s):  
A. Singh ◽  
P. Cova ◽  
R. A. Masut
Keyword(s):  
Barrier Height ◽  
Schottky Diodes ◽  
Thermionic Emission ◽  
Reverse Current ◽  
Parameter Extraction ◽  
Interface Layer ◽  
Least Square ◽  
Reverse Bias Voltage ◽  
Zero Bias ◽  
Current Voltage

ABSTRACTEpitaxial p-InP/Au Schottky diodes were fabricated by evaporation of Au onto Zn doped epitaxial layers of InP grown by MOVPE, on a highly doped InP substrate. The reverse current-voltage (Ir-Vr) and 1 MHz capacitance-voltage (C-V) characteristics of the Au/p-InP diodes were measured in the temperature range 220-393 K. At all temperatures, soft reverse current-voltage characteristics were observed, which may be due to the decrease in the effective Schottky barrier height (øbr) with the increase of Vr. The voltage dependence of the reverse current was well described in terms of the interface layer thermionic emission (ITE) model which incorporates the effects of applied reverse voltage drop and the transmission coefficient across the interface layer and image force lowering of the barrier height into the thermionic emission theory. A self consistent iteration and least square fitting technique was used to obtain the zero bias barrier height (øbo) and interface layer capacitance (Ci) from the Ir-Vr data. Both, the Ir-Vr and the C-V data were analyzed under the assumption of reverse bias voltage independence of the charge trapped in the interface states, which was supported by our experimental data. The values of øbo obtained from the C-V measurements agreed well with those obtained from the Ir-Vr data for a value of 0.45 AK−2cm−2 for the effective Richardson constant (Aeff).

Space charge capacitance spectroscopy in amorphous silicon Schottky diodes: Theory, modeling, and experiments

2012 ◽  
Vol 358 (17) ◽  
pp. 2007-2010 ◽  
Author(s):  
O.A. Maslova ◽  
M.E. Gueunier-Farret ◽  
J. Alvarez ◽  
A.S. Gudovskikh ◽  
E.I. Terukov ◽  
...  
Keyword(s):  
Space Charge ◽  
Amorphous Silicon ◽  
Schottky Diodes ◽  
Modeling And Experiments ◽  
Capacitance Spectroscopy ◽  
Charge Capacitance

scholarly journals A Study of a-Sic/C-Si(n) Isotype Heterojunctions

1993 ◽  
Vol 16 (1) ◽  
pp. 55-64 ◽  
Author(s):  
N. Georgoulas ◽  
L. Magafas ◽  
A. Thanailakis
Keyword(s):  
Temperature Dependence ◽  
Crystalline Silicon ◽  
Diffusion Mechanism ◽  
Thermionic Emission ◽  
Reverse Current ◽  
Emission Mechanism ◽  
Drift Diffusion ◽  
Si Substrates ◽  
Current Voltage ◽  
Capacitance Voltage

In the present work a study of the electrical properties of heterojunctions between rf sputtered amorphous silicon carbide (a-SiC) thin films and n-type crystalline silicon (c-Si) substrates is reported. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics, as well as the temperature dependence of the current of a-SiC/c-Si(n) heterojunctions were measured. The I-V characteristics of a-SiC/ c-Si(n) heterojunctions exhibit poor rectification properties, with a high reverse current, at higher temperatures (T > 250K), whereas good rectification properties are obtained at lower temperatures (T < 250K). It was found that the a-SiC/c-Si(n) heterojunctions are isotype, suggesting that-the conductivity of a-SiC is n-type. The temperature dependence of the current (from 185K to 320K) showed that the majority carriers of c-Si(n) (i.e. electrons) are transported from c-Si(n) to a-SiC mainly by the thermionic emission mechanism, or by the drift-diffusion mechanism. From C-V measurements of a-SiC/c-Si(n) heterojunctions the electron affinity of a-SiC was found to be X1= 4.20 ± 0.04 eV. Finally, the a-SiC/ c-Si(n) isotype heterojunctions are expected to be interesting devices as infrared

scholarly journals Análisis de la característica corriente-voltaje de diodos orgánicos emisores de luz (OLEDs) basados en polímeros depositados por spin coating.

2010 ◽  
Vol 15 (1) ◽  
pp. 68 ◽  
Author(s):  
Henry Alberto Méndez-Pinzón ◽  
Diana Rocío Pardo-Pardo ◽  
Juan Pablo Cuéllar-Alvarado ◽  
Juan Carlos Salcedo-Reyes ◽  
Ricardo Vera ◽  
...  
Keyword(s):  
Organic Semiconductors ◽  
Spin Coating ◽  
Electrical Response ◽  
Thermionic Emission ◽  
Hole Transport ◽  
Organic Layer ◽  
Electric Response ◽  
Carrier Injection ◽  
Parasitic Currents ◽  
Spin Coater

<p>Polymer-based organic light-emitting diodes (OLEDs) with the structure ITO / PEDOT:PSS / MDMO-PPV / Metal were prepared by spin coating. It is known that electroluminescence of these devices is strongly dependent on the material used as cathode and on the deposition parameters of the polymer electroluminescent layer MDMO-PPV. <strong>Objective.</strong> In this work the effect of i) the frequency of the spin coater (1000-8000 rpm), ii) the concentration of the MDMO-PPV: Toluene solution, and iii) the material used as cathode (Aluminium or Silver) on the electrical response of the devices, was evaluated through current-voltage (I-V) measurements. <strong>Materials and methods</strong>. PEDOT:PPS and MDMO-PPV organic layers were deposited by spin coating on ITO substrates, and the OLED structure was completed with cathodes of aluminium and silver. The electric response of the devices was evaluated based on the I-V characteristics. <strong>Results.</strong> Diodes prepared with thinner organic films allow higher currents at lower voltages; this can be achieved either by increasing the frequency of the spin coater or by using concentrations of MDMO-PPV: Toluene lower than 2% weight. A fit of the experimental data showed that the diodes have two contributions to the current. The first one is attributed to parasitic currents between anode and cathode, and the other one is a parallel current through the organic layer, in which the carrier injection mechanism is mediated by thermionic emission. <strong>Conclusions.</strong> The results fitting and the energy level alignment through the whole structure show that PPV-based OLEDs are unipolar devices, with current mainly attributed to hole transport.</p> <p><strong>Key words:</strong> organic semiconductors, OLEDs, electroluminescent polymers, MDMO-PPV, PEDOT:PSS, Spin coating, HOMO, LUMO, carrier injection, thermionic emission.</p><br />

Sign in / Sign up

Export Citation Format

Share Document