Ion Implanted Lateral p+-i-n+ Diodes on HPSI 4H-SiC

2015 ◽  
Vol 821-823 ◽  
pp. 620-623
Author(s):  
Roberta Nipoti ◽  
Francesco Moscatelli ◽  
Alberto Roncaglia ◽  
Filippo Bonafè ◽  
Fulvio Mancarella ◽  
...  
Keyword(s):  
Detection Limit ◽  
Reverse Bias ◽  
Low Voltage ◽  
Reverse Current ◽  
Intrinsic Region ◽  
Exponential Trend ◽  
Increasing Temperature ◽  
The Given ◽  
Instrument Detection Limit ◽  
Lateral Length

Square shaped annular lateral p+–i–n+ diodes on high purity semi-insulating (HPSI) 4H-SiC are fabricated by Al+ and P+ ion implantation to obtain anode and cathode regions, respectively. All the diodes have the same size central anode surrounded by an intrinsic region, which is surrounded by an annular cathode. Anode area and annular cathode width are fixed for all diodes, only the lateral length of the intrinsic region is varied. Post implantation annealing is performed at 1950 °C for 10 min. Static forward and reverse characteristics are measured in the temperature range of 30 - 290 °C. For all diodes, the reverse current is below the instrument detection limit of 10-14 A up to 100 °C at 200 V, the maximum reverse bias employed in this study. The reverse current increased up to low 108 A for 200 V reverse bias at 290 °C. Forward currents overlap at the low voltage region once they exceed the instrument detection limit at ~1.6 V and 30 °C. The forward currents follow almost identical exponential trend at all measured temperatures while the diode series resistance increase with increasing anode-cathode distance and decreased with increasing temperature for the given intrinsic region lateral length.

Scanned Electron Beam Annealing of Boron-Implanted Diodes

1980 ◽  
Vol 1 ◽  
Author(s):  
T. O. Yep ◽  
R. T. Fulks ◽  
R. A. Powell
Keyword(s):  
Electron Beam ◽  
Ion Implantation ◽  
Reverse Bias ◽  
Carrier Lifetime ◽  
Reverse Current ◽  
Electrical Activation ◽  
Electrical Characteristics ◽  
Low Resolution ◽  
Implantation Damage ◽  
Dopant Redistribution

ABSTRACTSuccessful annealing of p+ n arrays fabricated by ion-implantation of 11B (50 keV, 1 × 1014 cm-2) into Si (100 has been performed using a broadly rastered, low-resolution (0.25-inch diameter) electron beam. A complete 2" wafer could be uniformly annealed in ≃20 sec with high electrical activation (>75%) and small dopant redistribution (≃450 Å). Annealing resulted In p+n junctions characterized by low reverse current (≃4 nAcm-2 at 5V reverse bias) and higher carrier lifetime (80 μsec) over the entire 2" wafer. Based on the electrical characteristics of the diodes, we estimate that the electron beam anneal was able to remove ion implantation damage and leave an ordered substrate to a depth of 5.5 m below the layer junction.

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.

P+ implanted 6H-SiC n+-i-p diodes: evidence for a post-implantation-annealing dependent defect activation

2014 ◽  
Vol 1693 ◽  
Author(s):  
R. Nipoti ◽  
M. Puzzanghera ◽  
F. Moscatelli
Keyword(s):  
Activation Energy ◽  
Temperature Dependence ◽  
Ideality Factor ◽  
Low Voltage ◽  
Reverse Current ◽  
Forward Current ◽  
Current Region ◽  
Recombination Centers ◽  
Energy Dependent ◽  
Post Implantation

ABSTRACTTwo n+-i-p 6H-SiC diode families with P+ ion implanted emitter have been processed with all identical steps except the post implantation annealing: 1300°C/20min without C-cap has been compared with 1950°C/10min with C-cap. The analysis of the temperature dependence of the reverse current at low voltage (-100V) in the temperature range 27-290°C shows the dominance of a periphery current which is due to generation centers with number and activation energy dependent on the post implantation annealing process. The analysis of the temperature dependence of the forward current shows two ideality factor n region, one with n = 1.9/2 at low voltage and the other one with 1 < n < 2 without passing through 1 for increasing voltages. For both the diode families the current with n = 1.9/2 is a periphery current due to recombination centers with a thermal activation energy near the 6H-SiC mid gap. In the forward current region of 1 < n < 2, the two diode families show different ideality factor values which could be attributed to a different post implantation annealing defect activation.

High-Temperature (up to 800 K) Operation of 6-kV 4H-SiC Junction Diodes

2006 ◽  
Vol 527-529 ◽  
pp. 1339-1342 ◽  
Author(s):  
Michael E. Levinshtein ◽  
Pavel A. Ivanov ◽  
Mykola S. Boltovets ◽  
Valentyn A. Krivutsa ◽  
John W. Palmour ◽  
...  
Keyword(s):  
Deep Level ◽  
Reverse Current ◽  
Differential Resistance ◽  
Base Resistance ◽  
Small Current ◽  
Current Voltage ◽  
Current Voltage Characteristics ◽  
Increasing Temperature ◽  
Surface Leakage ◽  
And Diffusion

Steady-state and transient characteristics of packaged 6-kV 4H-SiC junction diodes have been investigated in the temperature range Т = 300 – 773 К. Analysis of the forward current-voltage characteristics and reverse current recovery waveforms shows that the lifetimeτ of non-equilibrium carriers in the base of the diodes steadily increases with temperature across the entire temperature interval. The rise in τ and decrease in carrier mobilities and diffusion coefficients with increasing temperature nearly compensate each other as regards their effect on the differential resistance of the diode, Rd. As a result, Rd is virtually temperature independent. An appreciable modulation of the base resistance takes place at room temperature even at a relatively small current density j of 20 A/cm2. At T = 800 K and j = 20 A/cm2, a very deep level of the base modulation has been observed. The bulk reverse current is governed by carrier generation in the space-charge region via a trap with activation energy of 1.62 eV. The surface leakage current of packaged structures does not exceed 2×10-6 А at T = 773 K and a reverse bias of 300 V.

Effects of Very High Neutron Fluence Irradiation on p+n Junction 4H-SiC Diodes

2007 ◽  
Vol 556-557 ◽  
pp. 917-920 ◽  
Author(s):  
Francesco Moscatelli ◽  
Andrea Scorzoni ◽  
Antonella Poggi ◽  
Mara Passini ◽  
Giulio Pizzocchero ◽  
...  
Keyword(s):  
Leakage Current ◽  
Leakage Current Density ◽  
Current Density ◽  
Reverse Bias ◽  
Neutron Fluence ◽  
Signal To Noise Ratio ◽  
Reverse Current ◽  
Low Noise ◽  
High Signal ◽  
Very High

In this work we analyzed the radiation hardness of SiC p+n diodes after very high 1 MeV neutron fluence. The diode structure is based on a p+ emitter ion implanted in n-type epilayer with thickness equal to 5 %m and donor doping ND = 3×1015 cm-3. Before irradiation, the average leakage current density at 100 V reverse bias was of the order of 3 nA/cm2. These devices were irradiated at four different fluence values, logarithmically distributed in the range 1014-1016 (1 MeV) neutrons/cm2. After irradiation the epilayer material became more resistive, as indicated by the reduction of the forward and reverse current density at a given voltage. In particular, after a neutron fluence of 1×1014 n/cm2 the epilayer active doping concentration decreased to 1.5×1015 cm-3. After irradiation at 1016 n/cm2, i.e. the highest fluence value, the average leakage current density at 100 V reverse bias decreased to values of the order of 0.1 nA/cm2. This very low noise even after very high fluence is very important to obtain a high signal to noise ratio even at room temperature.

scholarly journals Study of Low Voltage Prebreakdown Sites in Multicrystalline Si Based Cells by the LBIC, EL, and EDS Methods

2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
V. I. Orlov ◽  
E. B. Yakimov ◽  
E. P. Magomedbekov ◽  
A. B. Danilin
Keyword(s):  
Electron Beam ◽  
Laser Beam ◽  
Reverse Bias ◽  
Low Voltage ◽  
Depletion Region ◽  
Extended Defects ◽  
Induced Current ◽  
X Ray ◽  
Si Solar Cells ◽  
Electron Beam Induced Current

Breakdown sites in multicrystalline Si solar cells have been studied by reverse-bias electroluminescence, electron beam induced current (EBIC) and laser beam induced current (LBIC), and Energy Dispersive X-Ray Spectroscopy methods. In the breakdown sites revealed by EL at small reverse bias (~5 V), the enhanced aluminum and oxygen concentration is revealed. Such breakdowns can be located inside the depletion region because they are not revealed by the EBIC or LBIC methods. Breakdowns revealed by EL at larger bias correlate well with extended defects in the EBIC and LBIC images.

High Electric Field Forming of a-Si:H P-I-N Diodes

1995 ◽  
Vol 377 ◽  
Author(s):  
A. Ilie ◽  
B. Equer ◽  
T. Pochet
Keyword(s):  
Electric Field ◽  
Density Of States ◽  
Reverse Bias ◽  
Spectral Response ◽  
Reverse Current ◽  
Small Decrease ◽  
Forming Process ◽  
Dopant Activation ◽  
Long Period ◽  
High Reverse Bias

ABSTRACTAmorphous hydrogenated p-i-n diodes submitted to a high reverse bias for a long period of time undergo a metastable evolution which tends to improve their properties. A forming procedure based on this effect has been developed and leads to a significant decrease of the reverse current and increase of the breakdown voltage. In this paper, the mechanisms underlying this forming process have been investigated using the Constant Photocurrent Method (CPM), (I-V) characteristics and Spectral Response under reverse bias. The effects of annealing and current induced defect creation have been studied. The forming process is found to be most consistent with a metastable increase in the dopant activation of the p-layer and a small decrease of the density of states in the i-layer.

Research of the Undervoltage Tripper with Overvoltage Protection Function

2012 ◽  
Vol 614-615 ◽  
pp. 1201-1204
Author(s):  
Chang Chun Chi ◽  
Lin Fang Hu ◽  
Yi Wu
Keyword(s):  
High Voltage ◽  
Low Voltage ◽  
Supply Voltage ◽  
Circuit Breaker ◽  
Electrical Network ◽  
Operating Region ◽  
Voltage Change ◽  
Network Quality ◽  
Overvoltage Protection ◽  
The Given

The undervoltage tripper is a protection accessory of the low voltage apparatus and can turn off the circuit-breaker automatically when the power occurs lowering out off the given range. As a result of electrical network quality and manufacture procedure and so on, the failure rate of the circuit-breaker’s undervoltage tripper is high and always solved difficultly. This paper proposes one kind of adaptive undervoltage tripper with overvoltage protection function. It can adapt the supply voltage change automatically, absorb overvoltage, block the undervoltage tripper’s coil voltage, cause the operating region of the undervoltage tripper without high voltage dead area and improve the circuit-breaker work’s reliability.

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 Influence of Defects on Solar Cell Characteristics

2009 ◽  
Vol 156-158 ◽  
pp. 1-10 ◽  
Author(s):  
Otwin Breitenstein ◽  
Jan Bauer ◽  
Pietro P. Altermatt ◽  
Klaus Ramspeck
Keyword(s):  
Solar Cells ◽  
Reverse Bias ◽  
Present Knowledge ◽  
Silicon Solar Cells ◽  
Extended Defects ◽  
Exponential Behavior ◽  
Current Voltage ◽  
Recombination Current ◽  
Bias Range ◽  
The Given

The current-voltage (I-V) characteristics of most industrial silicon solar cells deviate rather strongly from the exponential behavior expected from textbook knowledge. Thus, the recombination current may be orders of magnitude larger than expected for the given material quality and often shows an ideality factor larger than 2 in a wide bias-range, which cannot be explained by classical theory either. Sometimes, the cells contain ohmic shunts although the cell’s edges have been perfectly insolated. Even in the absence of such shunts, the characteristics are linear or super-linear under reverse bias, while a saturation would be classically expected. Especially in multicrystalline cells the breakdown does not tend to occur at -50 V reverse bias, as expected, but already at about -15 V or even below. These deviations are typically caused by extended defects in the cells. This paper reviews the present knowledge of the origin of such non-ideal I-V characteristics of silicon solar cells and introduces new results on recombination involving coupled defect levels.

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