2620 prelim 1 things to know

important values/concepts to know

Resistivity of Cu

1.69 µΩ-cm

Resistivity of Ag

1.47 µΩ-cm

Range of relative permittivity dielectric constant (ε_r)

Between 3-20

Relative permittivity dielectric constant for water

81.1

Relative permittivity dielectric constant for air

1.000576

Conductivity of a good metal

10^5 S/cm = 10^7 S/m

Resistivity of a good metal

10-20 nΩ-m or 1-2 µΩ-cm

Thermal velocity for an electron in a metal

10^8 cm/s = 10^6 m/s

Boltzmann’s constant (J)

1.38 × 10^-23 J/K

Boltzmann’s constant (eV)

8.616 × 10^-5 eV/K

Thermal velocity for semiconductors

10^5 m/s

What is the order of magnitude for mean free path, l?

10 nm

Typical scattering time?

20 fs (10^-15)

Temperature dependence of phonon scattering time?

1/T

Temperature dependence of alloy scattering?

none

Units of mobility

cm²/V-s

Mobility of electrons in Cu at 300 K

44 cm²/V-s

Mobilities for metals

1-40 cm²/V-s

mobility for polymers/ionic materials

10^-5 cm²/V-s

Atomic density of Si

5 × 10^(22) atoms/cm³

typical atomic density of materials

10^(23) atoms/cm³

Mobility of electrons in a good metal

35 cm²/V-s

Matthiessen’s Rule

inverse of scattering time = sum of inverses of scattering times due to phonon, impurity, GBs, etc.

Barn unit

10^-24 cm² = 10^-28 m²

Max resistance of an alloy occurs at which %

50%

typical values for thermal conductivity in metals

10-400 W/m-K

range of visible light spectrum

400 to 700 nm

value of KbT at 300 K

0.02586 eV ~1/40 eV

Earth’s magnetic field

~0.5 Gauss = 5E-5 Tesla