Constants

Physical Constants

elementary charge	\(e\) or \(q\)	\(1.602\times10^{-19}\) C
Speed of light	\(c\)	\(2.998\times10^{8}\) m/s
Boltzmann constant	\(k\)	\(8.617\times10^{-5}\) eV⋅K^-1
Boltzmann constant	\(k\)	\(1.381\times10^{-23}\) J⋅K^-1
electric permittivity (vacuum)	\(\varepsilon_0\)	\(8.854\times10^{-12}\) F⋅m^-1
electric permittivity (vacuum)	\(1/\mu_0c^2\)	\(8.854\times10^{-12}\) F⋅m^-1
magnetic permeability (vacuum)	\(\mu_0\)	\(1.256\times10^{-6}\) N⋅A^-2
Avogadro constant	\(N_A\)	\(6.022\times10^{23}\) mol^-1
Planck constant	\(h\)	\(6.626\times10^{-34}\) J⋅s
Planck constant	\(h\)	\(4.136\times10^{-15}\) eV⋅s

\[\kappa = \varepsilon = \varepsilon_r \varepsilon_0\]

\[E = \frac{hc}{\lambda}\]

Group	Material	Type	Band gap (eV) at 302K
IV	Silicon	Indirect	1.14
IV	Germanium	Indirect	0.67
III-V	GaAs	Direct	1.43

\[V_T = \frac{kT}{q}\]