The effect of carrier diffusion on laser heating of lightly damaged semiconductors

1980 ◽  
Vol 51 (5) ◽  
pp. 2866 ◽  
Author(s):  
Jaroslava Z. Wilcox
Keyword(s):  
Laser Heating ◽  
Carrier Diffusion

Laser heating of semiconductors—effect of carrier diffusion in nonlinear dynamic heat transport process

1981 ◽  
Vol 52 (8) ◽  
pp. 4995-5006 ◽  
Author(s):  
Dae M. Kim ◽  
D. L. Kwong ◽  
Rajiv R. Shah ◽  
D. Lloyd Crosthwait
Keyword(s):  
Heat Transport ◽  
Nonlinear Dynamic ◽  
Laser Heating ◽  
Transport Process ◽  
Carrier Diffusion ◽  
Heat Transport Process

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.

Anisotropic Charge Carrier Diffusion Correlated to Ferroelastic Twin Domains in MAPbI3 Perovskite

2019 ◽  
Author(s):  
Ilka M. Hermes ◽  
Andreas Best ◽  
Julian Mars ◽  
Sarah M. Vorpahl ◽  
Markus Mezger ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Carrier Diffusion ◽  
Charge Carrier Diffusion

scholarly journals Aggregation affects optical properties and photothermal heating of gold nanospheres

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yiru Wang ◽  
Zhe Gao ◽  
Zonghu Han ◽  
Yilin Liu ◽  
Huan Yang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Cross Section ◽  
Laser Heating ◽  
Dipole Approximation ◽  
Gold Nanospheres ◽  
Extinction Cross Section ◽  
Heating Efficiency ◽  
Photothermal Heating ◽  
New Framework ◽  
Laser Calorimetry

AbstractLaser heating of gold nanospheres (GNS) is increasingly prevalent in biomedical applications due to tunable optical properties that determine heating efficiency. Although many geometric parameters (i.e. size, morphology) can affect optical properties of individual GNS and their heating, no specific studies of how GNS aggregation affects heating have been carried out. We posit here that aggregation, which can occur within some biological systems, will significantly impact the optical and therefore heating properties of GNS. To address this, we employed discrete dipole approximation (DDA) simulations, Ultraviolet–Visible spectroscopy (UV–Vis) and laser calorimetry on GNS primary particles with diameters (5, 16, 30 nm) and their aggregates that contain 2 to 30 GNS particles. DDA shows that aggregation can reduce the extinction cross-section on a per particle basis by 17–28%. Experimental measurement by UV–Vis and laser calorimetry on aggregates also show up to a 25% reduction in extinction coefficient and significantly lower heating (~ 10%) compared to dispersed GNS. In addition, comparison of select aggregates shows even larger extinction cross section drops in sparse vs. dense aggregates. This work shows that GNS aggregation can change optical properties and reduce heating and provides a new framework for exploring this effect during laser heating of nanomaterial solutions.

scholarly journals Extracting in Situ Charge Carrier Diffusion Parameters in Perovskite Solar Cells with Light Modulated Techniques

2021 ◽  
pp. 2248-2255
Author(s):  
Agustín Bou ◽  
Haralds A̅boliņš ◽  
Arjun Ashoka ◽  
Héctor Cruanyes ◽  
Antonio Guerrero ◽  
...  
Keyword(s):  
Solar Cells ◽  
Charge Carrier ◽  
Perovskite Solar Cells ◽  
Carrier Diffusion ◽  
Diffusion Parameters ◽  
Charge Carrier Diffusion
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