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

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.

Download Full-text

The determination of impact ionization coefficients in (100) gallium arsenide using avalanche noise and photocurrent multiplication measurements

IEEE Transactions on Electron Devices ◽

10.1109/t-ed.1985.22295 ◽

1985 ◽

Vol 32 (11) ◽

pp. 2454-2466 ◽

Cited By ~ 116

Author(s):

G.E. Bulman ◽

V.M. Robbins ◽

G.E. Stillman

Keyword(s):

Gallium Arsenide ◽

Impact Ionization ◽

Ionization Coefficients

Download Full-text

The determination of impact ionization coefficients in ln0.2Ga0.8As/GaAs strained-layer superlattice mesa photodiodes

Journal of Electronic Materials ◽

10.1007/bf02659635 ◽

1986 ◽

Vol 15 (4) ◽

pp. 221-227 ◽

Cited By ~ 3

Author(s):

G. E. Bulman ◽

T. E. Zipperian ◽

L. R. Dawson

Keyword(s):

Impact Ionization ◽

Strained Layer ◽

Strained Layer Superlattice ◽

Ionization Coefficients

Download Full-text

Determination of impact ionization coefficients in InP by analysis of photomultiplication and noise measurements

10.1109/iedm.1981.190066 ◽

1981 ◽

Cited By ~ 2

Author(s):

G.E. Bulman ◽

L.W. Cook ◽

M.M. Tashima ◽

G.E. Stillman

Keyword(s):

Impact Ionization ◽

Noise Measurements ◽

Ionization Coefficients

Download Full-text

Estimates of Impact Ionization Coefficients in Superlattice-Based Mid-Wavelength Infrared Avalanche Photodiodes

MRS Proceedings ◽

10.1557/proc-799-z3.1 ◽

2003 ◽

Vol 799 ◽

Author(s):

C. H. Grein ◽

K. Abu El-Rub ◽

M. E. Flatté ◽

H. Ehrenreich

Keyword(s):

Valence Band ◽

Impact Ionization ◽

Energy Gap ◽

Avalanche Photodiodes ◽

Threshold Energy ◽

Type Ii ◽

Band Engineering ◽

Type Ii Superlattice ◽

Low Threshold ◽

Ionization Coefficients

ABSTRACTWe describe band engineering strategies to either enhance or suppress electron-initiated impact ionization relative to hole-initiated impact ionization in type II superlattice mid-wavelength infrared avalanche photodiodes. The strategy to enhance electron-initiated impact ionization involves placing a high density of states at approximately one energy gap above the bottom of the conduction band and simultaneously removing valence band states from the vicinity of one energy gap below the top of the valence band. This gives the electrons a low threshold energy and the holes a high one. The opposite strategy enhances hole-initiated impact ionization. Estimates of the electron (α) and hole (β) impact ionization coefficients predict that α/β>>1 in the first type of superlattice and α/β<<1 in the second type.

Download Full-text

Impact ionization coefficients of 4H silicon carbide

Applied Physics Letters ◽

10.1063/1.1784520 ◽

2004 ◽

Vol 85 (8) ◽

pp. 1380-1382 ◽

Cited By ~ 71

Author(s):

T. Hatakeyama ◽

T. Watanabe ◽

T. Shinohe ◽

K. Kojima ◽

K. Arai ◽

...

Keyword(s):

Silicon Carbide ◽

Impact Ionization ◽

Ionization Coefficients

Download Full-text

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.

Download Full-text