Current Induced Degradation of a-Si:H Pin and Schottky Switches

1992 ◽  
Vol 258 ◽  
Author(s):  
K.J.B.M. Nieuwesteeg ◽  
J. Boogaard ◽  
G. Oversluizen
Keyword(s):  
Reverse Bias ◽  
Schottky Diodes ◽  
Forward Bias ◽  
Schottky Contact ◽  
Reverse Current ◽  
Bias Current ◽  
Hole Injection ◽  
Carrier Injection ◽  
Degradation Behaviour ◽  
Current Stress

ABSTRACTForward-bias current stress experiments were performed on α-Si:H p-i-n and Schottky switches at several temperatures and at current densities up to 6 A/cm2. In Schottky diodes, current stressing results in a lowering of the forward-bias SCLC current together with an increase of its thermal activation energy. The reverse current is unaffected. The rate of degradation of the forward current increases with increasing temperature. From a comparison of the degradation behaviour of Schottky's with different barrier height we find that the rate of degradation is correlated to the minority-carrier injection ratio of the Schottky contact. The effects are interpreted as being due to metastable state creation in the bulk α-Si:H. The rectifying properties of the metal-to-semiconductor contact are relatively stable to current stress.The forward-bias I-V curves of p-i-n diodes degrade much faster than those of the Schottky switches. At the same time, the reverse-bias current increases due to the stress. The lower stability to current-stress of p-i-n diodes is ascribed to the much higher hole injection in the mesa. After a short time, the reverse-bias current becomes dominated by e-h generation from the created deep states in the i-layer and then gives a direct indication of its time dependence.

scholarly journals Silicon carbide schottky diodes forward and reverse current properties upon fast electron radiation

2019 ◽  
Vol 8 (2) ◽  
pp. 428-437
Author(s):  
M. Azim Khairi ◽  
Rosminazuin Ab. Rahim ◽  
Norazlina Saidin ◽  
Yusof Abdullah ◽  
Nurul Fadzlin Hasbullah
Keyword(s):  
Silicon Carbide ◽  
Electron Irradiation ◽  
Ideality Factor ◽  
Reverse Bias ◽  
Series Resistance ◽  
Schottky Diodes ◽  
Forward Bias ◽  
Bias Current ◽  
Saturation Current ◽  
Order Of Magnitude

This paper investigates on the reaction of 10 and 15MGy, 3MeV electron irradiation upon off-the-shelves (commercial) Silicon Carbide Schottky diodes from Infineon Technologies (model: IDH08SG60C) and STMicroelectronics (model: STPSC806). Such irradiation reduces the forward-bias current. The reduction is mainly due to the significant increase of the series resistance (i.e. Infineon: 1.45Ω at before irradiation → 121×103 Ω at 15MGy); STMicroelectronics: 1.44Ω at before irradiation → 2.1×109 Ω at 15MGy). This increase in series resistance gives 4.6 and 8.2 orders of magnitude reduction for the forward-bias current density of Infineon and STMicroelectronics respectively. It is also observed that the ideality factor and the saturation current of the diodes increases with increasing dose (i.e. ideality factor- Infineon: 1.01 at before irradiation → 1.05 at 15MGy; STMicroelectronics: 1.02 at before irradiation → 1.3 at 15MGy | saturation current- Infineon: 1.6×10-17A at before irradiation → 2.5×10-17A at 15MGy; STMicroelectronics: 2.4×10-15A at before irradiation → 8×10-15A at 15MGy). Reverse-bias leakage current density in model by Infineon increases by one order of magnitude after 15MGy irradiation, however, in model by STMicroelectronics decreases by one order of magnitude. Overall, for these particular samples studied, Infineon devices have shown to be better in quality and more radiation resistance toward electron irradiation in forward-bias operation while STMicroelectronics exhibit better characteristics in reverse-bias operation.

Comparison of Current and Light Induced Defects in a-Si:H

1993 ◽  
Vol 297 ◽  
Author(s):  
R.A. Street ◽  
W.B. Jackson ◽  
M. Hack
Keyword(s):  
Numerical Modelling ◽  
Reverse Bias ◽  
Defect Density ◽  
Reverse Current ◽  
Bias Current ◽  
Spatial Profile ◽  
Forward Current ◽  
Defect Creation ◽  
Induced Defects ◽  
Metastable Defect

Metastable defect creation by illumination and by a forward current in p-i-n devices are compared using CPM and reverse current measurements of the defect density. The data show that the same defects are formed by the two mechanisms, but with different spatial profiles. Numerical modelling shows how the spatial profile influences the reverse bias current.

Molecular Photodiode and Two-channel Optoelectronic Demultiplexer based on the [60]Fullerene-porphyrin Tetrad

2011 ◽  
Vol 64 (10) ◽  
pp. 1409 ◽  
Author(s):  
Kornelia Lewandowska ◽  
Konrad Szaciłowski
Keyword(s):  
Absorption Spectrum ◽  
High Intensity ◽  
Reverse Bias ◽  
Forward Bias ◽  
Bias Current ◽  
Switching Effect ◽  
Negative Polarization ◽  
Current Ratio ◽  
Substrate Potential ◽  
Positive Polarization

Photoelectrodes containing Langmuir–Blodget layers of [60]fullerene-porphyrin tetrad behave like photodiodes. Upon excitation within the whole absorption spectrum of the molecule they generate photocurrent, the direction of which depends on the conducting substrate potential. At negative polarization high intensity cathodic photocurrent are observed, while at positive polarization much weaker anodic photocurrents are observed. The forward-bias to reverse-bias current ratio amounts 5:1. Therefore the [60]fullerene-porphyrin tetrad is closely related to semiconductors showing photoelectrochemical photocurrent switching effect and is a promising material for molecular optoelectronics. It can be used as a simple molecular photodiode. Assignment of logic values to polarization of the photoelectrode and to light and photocurrent pulses results in a very efficient two-channel optoelectronic demultiplexer.

Photoresponse of Zinc Oxide-Polyaniline Junction at Different Light Intensities

2016 ◽  
Vol 705 ◽  
pp. 186-189 ◽  
Author(s):  
Everjoy S. Mones ◽  
Armida V. Gillado ◽  
Marvin U. Herrera
Keyword(s):  
Zinc Oxide ◽  
Light Intensity ◽  
Reverse Bias ◽  
Electronic Devices ◽  
Forward Bias ◽  
Bias Current ◽  
Oxide Semiconductor ◽  
Light Intensities ◽  
Promising Application ◽  
Doped Polyaniline

Polymer-oxide semiconductor exhibits a promising application on electronic devices. In this study, zinc oxide-polyaniline (ZnO-PAni) junctions were constructed which showed a photodiode-like behavior. The junctions were built through connecting the electrodeposited zinc oxide to electrodeposited HCl-doped polyaniline. Without illumination, the junctions exemplify a diode-like behavior (e.g., large amount current at forward-bias while small amount of current at reverse-bias). When illuminated, the junctions exhibit a photodiode-like behavior. In such, the reverse-bias current increases with light intensity.

A Comparative Study Of GaN Diodes Grown by MBE on Sapphire and HVPE-GaN /Sapphire Substrates

1999 ◽  
Vol 595 ◽  
Author(s):  
Anand V. Sampath ◽  
Mira Misra ◽  
Kshitij Seth ◽  
Yuri. Fedyunin ◽  
Hock M. Ng ◽  
...  
Keyword(s):  
Comparative Study ◽  
Reverse Bias ◽  
Schottky Diodes ◽  
Forward Bias ◽  
Etch Pits ◽  
Sapphire Substrates ◽  
Fabrication And Characterization

AbstractIn this paper we report on the fabrication and characterization of GaN diodes (Schottky and p-n junctions) grown by plasma assisted MBE. We observed that Schottky diodes improve both in reverse as well as forward bias when deposited on 5 μm thick HVPE n+-GaN/sapphire instead of bare sapphire substrates. These improvements are attributed to the reduction of disloctions in the MBE homoepitaxially grown GaN. Similar benefits are observed in the reverse bias of the p-n junctions which according to EBIC measurements are attributed to the reduction of etch pits in the MBE grown p-GaN.

ZnO Nanowire/p-GaN Heterojunction LEDs

2007 ◽  
Vol 1018 ◽  
Author(s):  
Heiko O. Jacobs ◽  
Jesse Cole ◽  
Amir M. Dabiran ◽  
Heiko O. Jacobs
Keyword(s):  
Reverse Bias ◽  
Forward Bias ◽  
Zno Nanowires ◽  
Hole Injection ◽  
Zno Nanowire ◽  
Defect States ◽  
Light Emitting ◽  
Current Voltage ◽  
Distinct Color ◽  
Two Peaks

AbstractThis article reports forward and reverse biased emission in vertical ZnO nanowire/p-GaN heterojunction light emitting diodes (LEDs) grown out of solution on Mg-doped p-GaN films. The electroluminescence spectra under forward and reverse bias are distinctly different. Forward bias showed two peaks centered around 390 nm and 585 nm, while reverse bias showed a single peak at 510 nm. Analysis of the current-voltage characteristics and electroluminescence spectra is presented to determine the transport mechanism and location of electron hole recombination. Reverse bias transport and luminescence are attributed to hot-hole injection from the ZnO nanowires into the GaN film through tunneling breakdown. Forward bias transport and luminescence are attributed to hole injection from the GaN into the ZnO and recombination at defect states inside the ZnO yielding distinct color variations between individual wires. Major resistive losses occurred in the GaN lateral thin film connecting to the vertical ZnO nanowires.

scholarly journals Reverse biased nanocrystalline graphite (NCG)/p-Si schottky junction for methane gas sensor

2019 ◽  
Vol 15 (3) ◽  
pp. 1217
Author(s):  
A. A. Nawawi ◽  
S.M. Sultan ◽  
S.F.A. Rahmah ◽  
P.I. Khalid ◽  
S.H. Pu
Keyword(s):  
Barrier Height ◽  
Reverse Bias ◽  
Forward Bias ◽  
Schottky Contact ◽  
Schottky Junction ◽  
Methane Gas ◽  
Nanocrystalline Graphite ◽  
Current Shift ◽  
Metal Surface Layer ◽  
Bias Condition

An investigation on the effect of the reverse biased operation of NCG/p-Si Schottky contact during methane gas exposure at room temperature has been presented. The experimental results show the larger current shift at the reverse bias operation, compared to the forward bias by exposing to methane gas. This can be attributed to the adsorption of methane gas into the metal surface layer and produces a negative charge at the junction, thus reduces the barrier height of the device. The reverse barrier height was calculated under the reverse bias condition, demonstrated the value decreased from 0.58-0.53eV towards a higher concentration of methane gas. The Schottky junction also affected by the increase in a free carrier when exposure to the reducing gas such as methane. Raman spectra are reported to be detected at G, D and 2D band with the grain size 1.88nm to exhibit single crystallite graphite properties. The results correlate well with the 3D AFM scans reveal the RMS surface roughness of 1.1 to 2.8nm.

scholarly journals A Comparative Study Of GaN Diodes Grown by MBE on Sapphire and HVPE-GaN /Sapphire Substrates

2000 ◽  
Vol 5 (S1) ◽  
pp. 577-583
Author(s):  
Anand V. Sampath ◽  
Mira Misra ◽  
Kshitij Seth ◽  
Yuri. Fedyunin ◽  
Hock M. Ng ◽  
...  
Keyword(s):  
Comparative Study ◽  
Reverse Bias ◽  
Schottky Diodes ◽  
Forward Bias ◽  
Etch Pits ◽  
Sapphire Substrates ◽  
Fabrication And Characterization

In this paper we report on the fabrication and characterization of GaN diodes (Schottky and p-n junctions) grown by plasma assisted MBE. We observed that Schottky diodes improve both in reverse as well as forward bias when deposited on 5 μm thick HVPE n+-GaN/sapphire instead of bare sapphire substrates. These improvements are attributed to the reduction of disloctions in the MBE homoepitaxially grown GaN. Similar benefits are observed in the reverse bias of the p-n junctions which according to EBIC measurements are attributed to the reduction of etch pits in the MBE grown p-GaN.

scholarly journals Visible and Infrared Rare-Earth Activated Electroluminescence from Erbium Doped GaN

1999 ◽  
Vol 4 (S1) ◽  
pp. 940-945 ◽  
Author(s):  
M. Garter ◽  
R. Birkhahn ◽  
A. J. Steckl ◽  
J. Scofield
Keyword(s):  
Indium Tin Oxide ◽  
Ground State ◽  
Reverse Bias ◽  
Light Emission ◽  
Forward Bias ◽  
Bias Current ◽  
Emission Lines ◽  
Impact Excitation ◽  
Electron Impact Excitation ◽  
Ir Light

Room temperature visible and IR light electroluminescence (EL) has been obtained from Er-doped GaN Schottky barrier diodes. The GaN was grown by molecular beam epitaxy on Si substrates using solid sources (for Ga and Er) and a plasma source for N2. Transparent contacts utilizing indium tin oxide were employed. Strong green light emission was observed under reverse bias due to electron impact excitation of the Er atoms. Weaker emission was present under forward bias. The emission spectrum consists of two narrow green lines at 537 and 558 nm and minor peaks at 413, 461, 665, and 706 nm. There is also emission at 1000 nm and 1540 nm in the IR. The green emission lines have been identified as Er transitions from the 2H11/2 and 4S3/2 levels to the 4I15/2 ground state. The IR emission lines have been identified as transitions from the 4I11/2 and 4I13/2 levels to the 4I15/2 ground state. EL intensity for visible and IR light has a sub-unity power law dependence on bias current. An external quantum efficiency of 0.1% has also been demonstrated under a reverse bias current of 3.85 mA.

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