Carrier-diffusion measurements in silicon with a Fourier-transient-grating method

1994 ◽  
Vol 50 (23) ◽  
pp. 16943-16955 ◽  
Author(s):  
Jan Linnros ◽  
Vytautas Grivickas
Keyword(s):  
Transient Grating ◽  
Carrier Diffusion

Determination of carrier diffusion coefficient and lifetime in single crystalline CVD diamonds by light-induced transient grating technique

2010 ◽  
Vol 207 (9) ◽  
pp. 2058-2063 ◽  
Author(s):  
T. Malinauskas ◽  
K. Jarašiūnas ◽  
E. Ivakin ◽  
N. Tranchant ◽  
M. Nesladek
Keyword(s):  
Diffusion Coefficient ◽  
Transient Grating ◽  
Single Crystalline ◽  
Carrier Diffusion

Carrier diffusion characterization in epitaxial 4H–SiC

2001 ◽  
Vol 16 (2) ◽  
pp. 524-528 ◽  
Author(s):  
Paulius Grivickas ◽  
Jan Linnros ◽  
Vytautas Grivickas
Keyword(s):  
Diffusion Coefficient ◽  
Temperature Dependence ◽  
Power Law ◽  
Hole Mobility ◽  
Drift Mobility ◽  
Substantial Decrease ◽  
Transient Grating ◽  
Carrier Diffusion

Carrier diffusivity has been experimentally determined in low-doped n-type epitaxial 4H–SiC over a wide injection range using a Fourier transient grating technique. The data showed that, with injection, the diffusion coefficient increased from a minority-hole diffusivity Dh = 2.3 cm2/s to an ambipolar diffusivity Da = 4.2 cm2/s at approximately 1016 cm−3 with a substantial decrease occurring at higher injections. The derived Dh value corresponded to a minority-hole drift mobility of μh = 90 cm2/Vs, about 30% lower than available majority-hole mobilities. Also, the temperature dependence of the ambipolar diffusivity in the 296–523 K range has been determined. It followed a power law Da ∼ T−1.3 which notably differed from the expected one using the majority-hole mobility temperature dependence.

scholarly journals Comparison between Grating Imaging and Transient Grating Techniques on Measuring Carrier Diffusion in Semiconductor

2018 ◽  
Vol 22 (4) ◽  
pp. 348-359 ◽  
Author(s):  
Ke Chen ◽  
Xianghai Meng ◽  
Feng He ◽  
Yongjian Zhou ◽  
Jihoon Jeong ◽  
...  
Keyword(s):  
Transient Grating ◽  
Carrier Diffusion

Surface recombination effects on minority carrier diffusion length measurements using electron beam-induced current

1990 ◽  
Vol 48 (4) ◽  
pp. 744-745
Author(s):  
D.P. Malta ◽  
M.L. Timmons
Keyword(s):  
Electron Beam ◽  
Beam Energy ◽  
Minority Carrier ◽  
Diffusion Length ◽  
Effective Diffusion ◽  
Surface Recombination ◽  
Surface Recombination Velocity ◽  
Logarithmic Scale ◽  
Minority Carrier Diffusion Length ◽  
Carrier Diffusion

Measurement of the minority carrier diffusion length (L) can be performed by measurement of the rate of decay of excess minority carriers with the distance (x) of an electron beam excitation source from a p-n junction or Schottky barrier junction perpendicular to the surface in an SEM. In an ideal case, the decay is exponential according to the equation, I = Ioexp(−x/L), where I is the current measured at x and Io is the maximum current measured at x=0. L can be obtained from the slope of the straight line when plotted on a semi-logarithmic scale. In reality, carriers recombine not only in the bulk but at the surface as well. The result is a non-exponential decay or a sublinear semi-logarithmic plot. The effective diffusion length (Leff) measured is shorter than the actual value. Some improvement in accuracy can be obtained by increasing the beam-energy, thereby increasing the penetration depth and reducing the percentage of carriers reaching the surface. For materials known to have a high surface recombination velocity s (cm/sec) such as GaAs and its alloys, increasing the beam energy is insufficient. Furthermore, one may find an upper limit on beam energy as the diameter of the signal generation volume approaches the device dimensions.

Lifetime Regime in the Electrically-Detected Transient Grating Method Applied to Amorphous and Microcrystalline Silicon Films

2002 ◽  
Vol 715 ◽  
Author(s):  
P. Sanguino ◽  
M. Niehus ◽  
S. Koynov ◽  
P. Brogueira ◽  
R. Schwarz ◽  
...  
Keyword(s):  
Carrier Transport ◽  
Analytical Calculation ◽  
Chemical Vapor ◽  
Silicon Films ◽  
Dielectric Relaxation Time ◽  
Transient Grating ◽  
Minority Carrier Diffusion Length ◽  
Carrier Recombination ◽  
Thin Silicon ◽  
Good Agreement

AbstractThe minority-carrier diffusion length in thin silicon films can be extracted from the electrically-detected transient grating method, EDTG, by a simple ambipolar analysis only in the case of lifetime dominated carrier transport. If the dielectric relaxation time, τdiel, is larger than the photocarrier response time, τR, then unexpected negative transient signals can appear in the EDTG result. Thin silicon films deposited by hot-wire chemical vapor deposition (HWCVD) near the amorphous-to-microcrystalline transition, where τR varies over a large range, appeared to be ideal candidates to study the interplay between carrier recombination and dielectric response. By modifying the ambipolar description to allow for a time-dependent carrier grating build-up and decay we can obtain a good agreement between analytical calculation and experimental results.

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