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ω 3
Frequency shift of the longitudinal Raman mode
G and λ
Lame’s elastic constants
η
Generalized Poisson’s ratio
h b
Bending axis
h i
Top surface coordinate
h m
Midpoint coordinate
H
Via depth
ε c
Hygroscopic strain
σ T
Mismatch thermal stress
φ
Normalized concentration or activity
p amb
Ambient partial water vapor pressure
p g
Saturated water vapor pressure
P
Hydrostatic pressure
ν
Poisson’s ratio
˙
ϕ
Porosity growth rate
P
Partial water vapor pressure
Q
Activation energy for moisture diffusivity
H r
Residual via extrusion
S
Solubility
T re f
Stress-free temperature
γ e
The rate of elastic extrusion
γ p
The rate of plastic extrusion
D T
Thermal diffusivity
ε T
Thermal strain
T m
Maximum temperature during thermal cycling
T R
Room temperature
u i
Displacement vector
ε p
Vapor pressure-induced strain
W
Warpage
W
Wetness
X i
Body force vector
T
Thermal loading
κ app
Applied external curvature
κ
Curvature
κ nat
Natural bending-induced curvature
π 11, π 12, π 44 Piezoresistance coefficients
ρ g
Density of saturated water vapor
σ r
Radial stress
σ rz
Shear stress in r-z plane
σ z
Normal stress in z direction
β
Coefficient of hygroscopic swelling
φ
Porosity
ρ a
Apparent moisture density