Temperature dependence of the impact ionization coefficients in AlAsSb lattice matched to InP

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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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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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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Mean multiplication gain and excess noise factor of GaN and Al0.45Ga0.55N avalanche photodiodes

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200067 ◽

2020 ◽

Vol 92 (1) ◽

pp. 10301

Author(s):

Tat Lung Wesley Ooi ◽

Pei Ling Cheang ◽

Ah Heng You ◽

Yee Kit Chan

Keyword(s):

Electric Field ◽

Impact Ionization ◽

Avalanche Photodiodes ◽

Monte Carlo Model ◽

Noise Factor ◽

Excess Noise ◽

Excess Noise Factor ◽

Multiplication Gain ◽

Ionization Coefficients ◽

The Impact

In this work, Monte Carlo model is developed to investigate the avalanche characteristics of GaN and Al0.45Ga0.55N avalanche photodiodes (APDs) using random ionization path lengths incorporating dead space effect. The simulation includes the impact ionization coefficients, multiplication gain and excess noise factor for electron- and hole-initiated multiplication with a range of thin multiplication widths. The impact ionization coefficient for GaN is higher than that of Al0.45Ga0.55N. For GaN, electron dominates the impact ionization at high electric field while hole dominate at low electric field whereas Al0.45Ga0.55N has hole dominate the impact ionization at higher field while electron dominate the lower field. In GaN APDs, electron-initiated multiplication is leading the multiplication gain at thinner multiplication widths while hole-initiated multiplication leads for longer widths. However for Al0.45Ga0.55N APDs, hole-initiated multiplication leads the multiplication gain for all multiplication widths simulated. The excess noise of electron-initiated multiplication in GaN APDs increases as multiplication widths increases while the excess noise decreases as the multiplication widths increases for hole-initiated multiplication. As for Al0.45Ga0.55N APDs, the excess noise for hole-initiated multiplication increases when multiplication width increases while the electron-initiated multiplication increases with the same gradient at all multiplication widths.

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Comprehensive Study of Impact Ionization Coefficients of 4H-SiC

MRS Proceedings ◽

10.1557/proc-815-j9.3 ◽

2004 ◽

Vol 815 ◽

Cited By ~ 4

Author(s):

T. Hatakeyama ◽

T. Watanabe ◽

K. Kojima ◽

N. Sano ◽

T. Shinohe ◽

...

Keyword(s):

Electronic Structure ◽

Impact Ionization ◽

Avalanche Breakdown ◽

Doping Density ◽

Electric Field Dependence ◽

Saturation Velocity ◽

Large Anisotropy ◽

Ionization Coefficients ◽

The Impact ◽

Comprehensive Study

AbstractThe electric field dependence and anisotropy of the impact ionization coefficients of 4H-SiC are investigated by means of the avalanche breakdown behavior of p+n diodes. The breakdown voltages as a function of doping density and the multiplication factors of a leakage current are obtained using p+n diode fabricated on (0001) and (1120) 4H-SiC epitaxial wafers. The obtained impact ionization coefficients show large anisotropy; the breakdown voltage of a p+n diode on (1120) wafer is 60% of that on (0001) wafer. We have shown that anisotropy of the impact ionization coefficients is attributable to the anisotropy of saturation velocity originated from the electronic structure of 4H-SiC.

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On the temperature dependence of the impact ionization in HFET and the corresponding RF- and noise performance

Proceedings of 8th International Conference on Indium Phosphide and Related Materials ◽

10.1109/iciprm.1996.492334 ◽

2002 ◽

Author(s):

R. Renter ◽

T. Breder ◽

U. Auer ◽

S. Van Waasen ◽

M. Agethen ◽

...

Keyword(s):

Temperature Dependence ◽

Impact Ionization ◽

Noise Performance ◽

The Impact

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Avalanche Diodes with Low Temperature Dependence in 4H-SiC Suitable for Parallel Protection

Materials Science Forum ◽

10.4028/www.scientific.net/msf.679-680.567 ◽

2011 ◽

Vol 679-680 ◽

pp. 567-570 ◽

Cited By ~ 2

Author(s):

Duy Minh Nguyen ◽

Gontran Pâques ◽

Nicolas Dheilly ◽

Christophe Raynaud ◽

Dominique Tournier ◽

...

Keyword(s):

Low Temperature ◽

Temperature Dependence ◽

Impact Ionization ◽

Temperature Range ◽

Avalanche Diodes ◽

Ionization Coefficients

Avalanche diodes have been fabricated on 4H-SiC substrate. These diodes show an abrupt avalanche voltage of about 59 V which corresponds to the calculated theoretical one using our previously determined impact ionization coefficients. This avalanche voltage increases by as small as 3.7 mV/K over the investigated temperature range (150K-420K).

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