software to fit optical spectra - Quantum Materials Group

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Figure 4-10 The experimental configuration of the model “Ellipsometry of an orthorhombic film on an
orthorhombic substrate”.
All the formulas are the same as for the model “Ellipsometry of an orthorhombic
Sample” (section 4.7.3), except the ones for r p and r s , which are a bit more lengthy:
r
r
p
0 f
p
fs
rp
t
s
E inc
p
p
E inc
f
ε y
s
ε y
of
rp
+ t r
=
1+
t
θ p
Eref
fs
p p
of fs
pr
p rp
z
f
ε z
s
ε z
of fs
rs
+ t srs
, rs
= , where
of fs
1+
t r r
s
s
s
2
sin θ f
1−
− ε cosθ
f
x
f 2
ε
cosθ
− ε − sin θ
z
0 f
y
= , r s =
,
2
f 2
sin θ f
cosθ
+ ε y − sin θ
1−
+ ε x cosθ
f
ε
2
2
f sin θ s sin θ
ε x 1−
− ε
s
x 1−
f
ε z
ε z
= ,
2
2
f sin θ s sin θ
ε x 1−
+ ε x 1−
ε
ε
⎪⎧
2
⎪⎫
f sin θ
= ⎨4πiωd
ε x 1−
f ⎬
⎪⎩
ε z ⎪⎭
s
z
f
z
fs
r s
f 2
ε − sin θ −
f 2
ε − sin θ +
f 2
exp , s = exp{ 4πiωd
ε y − sin θ }
s
ε − sin
s
ε − sin
Guide to RefFIT Page 69
=
y
y
t , d is the thickness of
the top layer (measured in cm), ω is the light frequency (measured in cm -1 ).
The description of the model parameters is given in Table 4-11.
# Wo Wp G
1 DF model for ε θ [degrees] P [degrees]
f
x
f
ε x
s
ε x
s
Eref
d
y
y
2
2
θ
θ