Temperature Dependence of Hole Impact Ionization Coefficient in 4H-SiC Photodiodes

Hole initiated multiplication characteristics of 4H-SiC Separate Absorption and Multiplication Avalanche Photodiodes (SAM-APDs) with a n- multiplication layer of 2.7 µm were obtained using 325nm excitation at temperatures ranging from 300 to 450K. The breakdown voltages increased by 200mV/K over the investigated temperature range, which indicates a positive temperature coefficient. Local ionization coefficients, including the extracted temperature dependencies, were derived in the form of the Chynoweth expression and were used to predict the hole multiplication characteristics at different temperatures. Good agreement was obtained between the measured and the modeled multiplication using these ionization coefficients. The impact ionization coefficients decreased with increasing temperature, corresponding to an increase in breakdown voltage. This result agrees well with the multiplication characteristics and can be attributed to phonon scattering enhanced carrier cooling which has suppressed the ionization process at high temperatures. Hence, a much higher electric field is required to achieve the same ionization rates.

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Temperature Dependence of Impact Ionization Coefficients in 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.461 ◽

2014 ◽

Vol 778-780 ◽

pp. 461-466 ◽

Cited By ~ 14

Author(s):

Hiroki Niwa ◽

Jun Suda ◽

Tsunenobu Kimoto

Keyword(s):

Temperature Dependence ◽

Temperature Coefficient ◽

Breakdown Voltage ◽

Elevated Temperatures ◽

Phonon Scattering ◽

Impact Ionization ◽

Negative Temperature ◽

Positive Temperature Coefficient ◽

Positive Temperature ◽

Ionization Coefficients

Impact ionization coefficients of 4H-SiC were measured at room temperature and at elevated temperatures up to 200°C. Photomultiplication measurement was done in two complementary photodiodes to measure the multiplication factors of holes (Mp) and electrons (Mn), and ionization coefficients were extracted. Calculated breakdown voltage using the obtained ionization coefficients showed good agreement with the measured values in this study, and also in other reported PiN diodes and MOSFETs. In high-temperature measurement, breakdown voltage exhibited a positive temperature coefficient and multiplication factors showed a negative temperature coefficient. Therefore, extracted ionization coefficient has decreased which can be explained by the increase of phonon scattering. The calculated temperature dependence of breakdown voltage agreed well with the measured values not only for the diodes in this study, but also in PiN diode in other literature.

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The Temperature Dependent Breakdown Voltage For 4H- and 6H-SiC Diodes

MRS Proceedings ◽

10.1557/proc-622-t6.4.1 ◽

2000 ◽

Vol 622 ◽

Cited By ~ 3

Author(s):

Y. S. Lee ◽

M. K. Han ◽

Y. I. Choi

Keyword(s):

High Temperature ◽

Temperature Coefficient ◽

Breakdown Voltage ◽

Impact Ionization ◽

Positive Temperature Coefficient ◽

Positive Temperature ◽

Ionization Coefficient ◽

Temperature Dependent ◽

Increasing Temperature ◽

Temperature Applications

ABSTRACTThe breakdown voltages of 6H- and 4H-SiC rectifiers as function of temperature were modeled analytically in both non-reachthrough diode and reachthrough diode. The breakdown voltage was derived by the ionization integral employing accurate hole impact ionization coefficient. The breakdown voltage of SiC rectifiers was increased with increasing temperature and the positive temperature coefficient of breakdown voltage indicates that SiC rectifiers are suitable for high temperature applications. The breakdown voltages of both 6H- and 4H-SiC diodes were increased by M(T)-1/4 in NRDs and M(T)-1/8 in RDs.

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Avalanche Multiplication and Impact Ionisation in Separate Absorption and Multiplication 4H-SiC Avalanche Photodiodes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.600-603.1207 ◽

2008 ◽

Vol 600-603 ◽

pp. 1207-1210

Author(s):

W.S. Loh ◽

J.P.R. David ◽

Stanislav I. Soloviev ◽

H.Y. Cha ◽

Peter M. Sandvik ◽

...

Keyword(s):

Electric Fields ◽

Room Temperature ◽

Impact Ionization ◽

Avalanche Photodiodes ◽

Extreme Environment ◽

Positive Temperature Coefficient ◽

Positive Temperature ◽

Avalanche Multiplication ◽

Impact Ionisation ◽

Ionization Coefficients

The hole dominated avalanche multiplication characteristics of 4H-SiC Separate Absorption and Multiplication avalanche photodiodes (SAM-APDs) were determined experimentally and modeled using a local multiplication model. The 0.5x 0.5mm2 diodes had very low dark current and exhibited sharp, uniform breakdown at about 580V. The data agree with modeling result using extrapolated impact ionization coefficients reported by Ng et al. and is probably valid for electric fields as low as ~0.9MV/cm at room temperature provided that both the C-V measurements and electric field determination in this work are correct. The packaged devices demonstrate a positive temperature coefficient of breakdown voltage for temperatures ranging from 100K to 300K which is a desired feature for extreme environment applications.

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Pb-FREE SOLDERS: ESTIMATING OF SOME PHYSICOCHEMICAL AND THERMODYNAMIC PROPERTIES OF TERNARY Cu-Ag-In SYSTEM

Surface Review and Letters ◽

10.1142/s0218625x19500768 ◽

2019 ◽

Vol 26 (10) ◽

pp. 1950076 ◽

Cited By ~ 1

Author(s):

SALMA BELMOUJOUD ◽

RACHIDA M’CHAAR ◽

ABDELAZIZ SABBAR

Keyword(s):

Surface Tension ◽

Cross Sections ◽

Theoretical Models ◽

Enthalpy Of Mixing ◽

Positive Temperature Coefficient ◽

Ternary Alloys ◽

Positive Temperature ◽

Geometric Models ◽

Different Temperatures ◽

Increasing Temperature

The surface tension and viscosity in the liquid Cu-Ag-In ternary alloys have been estimated using Muggianu and Toop geometric models and Seetharaman–Sichen equations, respectively along a cross-section of [Formula: see text]/[Formula: see text], 1/1 and 2/1. The surface tension has also been estimated using Butler equation. In addition, the enthalpies of the same ternary alloys have been predicted at different temperatures along five cross-sections [Formula: see text]/[Formula: see text], 1/2, 1/1, 2/1 and 3/1 using Kohler, Toop and Chou models. The geometric models are used in this work in order to verify their effectiveness since they are considered as the most widespread theoretical models used for metallic alloys. The estimated values obtained show that the surface tension decreases with increasing temperature for the all studied models and equations and increase with increasing copper-composition, except for few Cu-compositions where an opposite tendency is observed. It should be noted that the surface tension has a negative and positive temperature coefficient (d[Formula: see text]/d[Formula: see text]. The viscosity decreases with increasing temperature but increases with increasing copper-compositions. The calculated surface tension and enthalpy of mixing of the investigated system are compared with the reachable experimental data and a relatively excellent accord was obtained.

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Measurement of the impact ionization rates in Al0.06Ga0.94Sb

Applied Physics Letters ◽

10.1063/1.103705 ◽

1990 ◽

Vol 57 (3) ◽

pp. 249-251 ◽

Cited By ~ 7

Author(s):

H. Kuwatsuka ◽

T. Mikawa ◽

S. Miura ◽

N. Yasuoka ◽

Y. Kito ◽

...

Keyword(s):

Impact Ionization ◽

The Impact ◽

Ionization Rates

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Effect of temperature on toxicity of selected insecticides to forest beetle Anoplotrupes Stercorosus / Interakcja temperatury z wybranymi insektycydami chrząszcza leśnego Anoplotrupes stercorosus

Chemistry-Didactics-Ecology-Metrology ◽

10.2478/cdem-2013-0023 ◽

2013 ◽

Vol 18 (1-2) ◽

pp. 103-108 ◽

Cited By ~ 1

Author(s):

Bartosz Piechowicz ◽

Przemysław Grodzicki

Keyword(s):

Temperature Coefficient ◽

Positive Temperature Coefficient ◽

Effect Of Temperature ◽

Positive Temperature ◽

Benzoyl Urea ◽

The Impact

Abstract In 2007 and 2008 research on the impact of temperature, ranging from 14 to 39°C on the survivability of an adult Anoplotrupes stercorosus intoxicated by insecticide preparations from the group of phosphoorganic insecticides (diazinon), carbamate (pirimicarb), quinazolines (fenazaquin), oxadiazine (indoxacarb), benzoyl urea insecticides (teflubenzuron), neonicotinoids (acetamiprid) and pyrethroids (beta-cyfluthrin) was carried out. The results obtained indicate that all preparations used in tests had a positive temperature coefficient.

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Determination of Impact Ionization Coefficients Measured from 4H Silicon Carbide Avalanche Photodiodes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.339 ◽

2007 ◽

Vol 556-557 ◽

pp. 339-342 ◽

Cited By ~ 1

Author(s):

W.S. Loh ◽

C. Mark Johnson ◽

J.S. Ng ◽

Peter M. Sandvik ◽

Steve Arthur ◽

...

Keyword(s):

Impact Ionization ◽

Avalanche Photodiodes ◽

Submicron Devices ◽

Illuminating Light ◽

Factor Data ◽

Ionization Coefficients ◽

P Type ◽

Dark Currents ◽

The Impact

Hole initiated avalanche multiplication characteristics of 4H-SiC avalanche photodiodes have been studied. The diodes had n+-n-p SiC epitaxial layers grown on a p-type substrate. These 1 mm2 devices had very low dark currents and exhibited sharp breakdown at voltages of approximately 500V. The diodes multiplication characteristics appeared to be identical when the wavelength of the illuminating light from the top varied from 288 to 325nm, implying that almost pure hole initiated multiplication was occurring. The multiplication factor data were modelled using a local multiplication model with impact ionization coefficients of 4H-SiC reported by various authors. The impact ionization coefficients extracted from submicron devices by Ng et al. were found to give accurate predictions for multiplication factors within the uncertainties of the doping levels. This result suggests that their ionization coefficients can be applied to thicker bulk 4H-SiC structures.

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Comparison of Electron and Hole Initiated Impact Ionization in Zincblende and Wurtzite Phase Gallium Nitride

MRS Proceedings ◽

10.1557/proc-468-457 ◽

1997 ◽

Vol 468 ◽

Cited By ~ 8

Author(s):

E. Bellotti ◽

I. H. Oguzman ◽

J. Kölnik ◽

K. F. Brennan ◽

R. Wang ◽

...

Keyword(s):

Applied Field ◽

Impact Ionization ◽

Full Range ◽

Wurtzite Phase ◽

Valence Bands ◽

Two Phases ◽

Ionization Coefficients ◽

Direct Numerical Integration ◽

Applied Fields ◽

Ionization Rates

ABSTRACTIn this paper, we present the first calculations of the electron and hole impact ionizatioi coefficients for both wurtzite and zincblende phase GaN as a function of the applied electrii field. The calculations are made using an ensemble Monte Carlo simulator including the ful details of the conduction and valence bands derived from an empirical pseudopotentia calculation. The interband impact ionization transition rates for both carrier species an determined by direct numerical integration including a wavevector dependent dielectric function It is found that the electron and hole ionization coefficients are comparable in zincblende Ga> at an applied field of ∼ 3 MV/cm, yet vary to a slight degree at both higher and lower applied field strengths. In the wurtzite phase, the electron and hole coefficients are comparable at hig] fields but diverge at lower applied fields. The most striking result is that the ionization rates an predicted to be substantially different for both carrier species between the two phases. It i predicted that the ionization rates for both carrier species in the zincblende phase are significanti; higher than in the wurtzite phase over the full range of applied fields examined.

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Effect of Pre- and Post-Treatment Temperatures, Age of Deposit, and Repellency on the Toxicity of Kelthane to the Two-spotted Mite, Tetranychus telarius (L.) (Acarina: Tetranychidae)

The Canadian Entomologist ◽

10.4039/ent961307-10 ◽

1964 ◽

Vol 96 (10) ◽

pp. 1307-1312 ◽

Cited By ~ 10

Author(s):

R. W. Fisher ◽

R. I. C. Hansell

Keyword(s):

Temperature Coefficient ◽

Spider Mite ◽

Positive Temperature Coefficient ◽

Positive Temperature ◽

Expected Number ◽

Significant Difference ◽

Treated Leaf ◽

Different Temperatures ◽

Pre Treatment ◽

Two Spotted Spider Mite

AbstractKelthane MF showed a positive temperature coefficient of toxicity to the two-spotted spider mite, Tetranychus telarius. An increase of about 1.2% mortality occurred for each degree rise in the range from 50-90°F. Pre-treatment of adult, female mites at three different temperatures for three days caused no significant difference in mortality at 74°F. Acaricidal potency of Kelthane MF on peach leaves declined rapidly both indoors and outdoors for the first two days. Thereafter the potency decreased at about the same rate outside, but much slower in the laboratory. Deposits on peach leaves repelled mites strongly for two days, but weakened rapidly over the next six days. Mites entered treated leaf areas after the acaricidal potency had dropped low, and so a larger than expected number of susceptible mites may have survived.

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