332
10 Recombination
makes dislocations appear as ‘dark line defects’ in luminescence imaging [1043]. In [1044] also the
decrease of carrier lifetime around (misfit) dislocations has been imaged. The effect of dislocations on
the radiative recombination efficiency depends on the diffusion length [1044].
10.13 Excess-Carrier Profiles
In this section, some typical excess-carrier profiles (in one-dimensional geometry) are discussed that
arise from certain excitation conditions. The excess-carrier density (here holes in an n-type semiconductor, i.e. = p n − p n 0 ) is determined by the diffusion equation (cf. (8.65a))
D p
∂
2
∂x 2 = −G(x) +
τ p
.
(10.63)
(a)
(b)
Fig. 10.33 a Minority carrier lifetime in (p-type) silicon as a function of grain boundary size. The dashed line has the
slope ∝ A. Data from [1039]. b Linescan of the electron beam induced current (EBIC) perpendicular to a single grain
boundary in silicon. The arrow denotes the position of the grain boundary. Compiled from [1040]
Fig. 10.34 Inverse
minority carrier lifetime in
n-type silicon (40 cm),
low resistivity Ge
(3–5 cm) and high
resistivity Ge
(30–40 cm). Data
from [1042]
10 Recombination
makes dislocations appear as ‘dark line defects’ in luminescence imaging [1043]. In [1044] also the
decrease of carrier lifetime around (misfit) dislocations has been imaged. The effect of dislocations on
the radiative recombination efficiency depends on the diffusion length [1044].
10.13 Excess-Carrier Profiles
In this section, some typical excess-carrier profiles (in one-dimensional geometry) are discussed that
arise from certain excitation conditions. The excess-carrier density (here holes in an n-type semiconductor, i.e. = p n − p n 0 ) is determined by the diffusion equation (cf. (8.65a))
D p
∂
2
∂x 2 = −G(x) +
τ p
.
(10.63)
(a)
(b)
Fig. 10.33 a Minority carrier lifetime in (p-type) silicon as a function of grain boundary size. The dashed line has the
slope ∝ A. Data from [1039]. b Linescan of the electron beam induced current (EBIC) perpendicular to a single grain
boundary in silicon. The arrow denotes the position of the grain boundary. Compiled from [1040]
Fig. 10.34 Inverse
minority carrier lifetime in
n-type silicon (40 cm),
low resistivity Ge
(3–5 cm) and high
resistivity Ge
(30–40 cm). Data
from [1042]