Nonequilibrium Carrier Recombination in Highly Excited Bulk SiC Crystals

2010 ◽  
Vol 645-648 ◽  
pp. 215-218 ◽  
Author(s):  
Kęstutis Jarašiūnas ◽  
Patrik Ščajev ◽  
Vytautas Gudelis ◽  
Paul B. Klein ◽  
Masashi Kato

We applied time-resolved free carrier absorption (FCA) to monitor non-equilibrium carrier dynamics in 4H epilayers and 3C SiC bulk crystals at excess carrier densities in the N = 1017 - 1019 cm-3 range. The numerical fitting of FCA decay kinetics provided the linear and nonlinear carrier recombination rates in the 40-390 K range and the absorption cross-sections eh at 1064 nm. In 4H, the decrease of the bulk lifetime (800 ns) with excitation provided the bimolecular and Auger coefficients B=(1.2±0.4)×10-12 cm3/s and C=(7±4)×10-31cm6/s, respectively, at room temperature. These values for 3C were 55-150 ns, (2.0±0.4)×10-12 cm3/s, and (2±1)×10-32 cm6/s, respectively. The rate of linear and nonlinear recombination increased at lower temperatures. A value of eh =4.4×10-18 cm2 for 3C SiC at 1.064 m was found 2.3 times smaller than that for 4H SiC.

2019 ◽  
Vol 126 (3) ◽  
pp. 271
Author(s):  
И.А. Каплунов ◽  
А.И. Колесников ◽  
Г.И. Кропотов ◽  
В.Е. Рогалин

AbstractThe transmission of intrinsic, antimony-doped, and gallium-doped Ge single crystals in the THz spectral range have been experimentally investigated. It is shown that the attenuation coefficient of intrinsic germanium in the range of 160‒220 μm is at a level of ~0.5 cm^‒1, a value comparable with that for silicon. The free-carrier absorption cross sections of silicon and germanium are significantly different, which may be caused by the difference in the mechanisms of carrier–phonon interaction in these materials.


MRS Advances ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 15-20
Author(s):  
Arseniy Buryakov ◽  
Dinar Khusyainov ◽  
Elena Mishina ◽  
Alexandr Yachmenev ◽  
Rustam Khabibullin ◽  
...  

ABSTRACTWe report on the time-resolved measurements of photocarrier dynamics in InGaAs/InAlAs superlattices with epitaxial stresses in a wide range of optical pump fluences. We demonstrated that the contribution of free carrier absorption and two-photon absorption to the carrier dynamics decreases with an increase of epitaxial stresses. The lowest relaxation times of 1.7 and 8.3 ps, respectively attributed to carrier trapping and carrier recombination, were obtained for the structure with maximum epitaxial stresses.


2013 ◽  
Vol 103 (9) ◽  
pp. 092101 ◽  
Author(s):  
Jet Meitzner ◽  
Frederick G. Moore ◽  
Brock M. Tillotson ◽  
Stephen D. Kevan ◽  
Geraldine L. Richmond

1994 ◽  
Vol 339 ◽  
Author(s):  
R. Tomashiunas ◽  
E. Vanagas ◽  
M. Petrauskas ◽  
A. Zhindulis ◽  
M. Willander ◽  
...  

ABSTRACTFast carrier recombination phenomena in 6H-SiC has been investigated. Evaluation of carrier recombination in nitrogen doped n-type 6H-SiC grown by the Lely method have been carried out using picosecond photoconductivity, time-resolved photoluminescence and dynamic gratings (DG) techniques. From photoluminescence measurements the hole capture by neutral (nitrogen) donors is discussed. The hole capture times and capture cross sections 820 ps, 2.32 ns and 1.5–10-15cm2, 1.2–10-15cm2, respectively, by each of the inequivalent donor were evaluated. From the photoconductivity measurements the electron lifetimes ∼ 1.5 μs at 300 K and (3.5÷6.5)μs at 125 K were obtained. The ambipolar diffusion coefficient 1.4 cm2.s-1 obtained from dynamic gratings measurements is in good coincidence with the calculated values.


2011 ◽  
Vol 679-680 ◽  
pp. 205-208 ◽  
Author(s):  
Jawad ul Hassan ◽  
Patrik Ščajev ◽  
Kęstutis Jarašiūnas ◽  
Peder Bergman

Free carrier dynamics has been studied in 4H- and 3C-SiC in a wide temperature range using time-resolved photoluminescence, free carrier absorption, and light induced transient grating techniques. Considerably high carrier lifetime was observed in 3C-SiC epitaxial layers grown on 4H-SiC substrates using hot-wall CVD with respect to previously reported values for 3C-SiC grown either on Si or on 6H-SiC substrates. The temperature dependences of carrier lifetime and diffusion coefficient for 4H- and 3C-SiC were compared. Shorter photoluminescence decay time with respect to free carrier absorption decay time was observed in the same 4H-SiC sample, while these techniques revealed similar trends in the carrier lifetime temperature dependencies. However, the latter dependences for hot-wall CVD-grown 3C layers were found different if measured by time resolved photoluminescence and free carrier absorption techniques.


Author(s):  
Yu. K. Bobretsova ◽  
D. A. Veselov ◽  
N. A. Rudova ◽  
V. A. Kapitonov ◽  
S. O. Slipchenko ◽  
...  

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