For Ge: mL 1.59m, and mr* = 0.0823mo For GaAs: me* = 0.0665mo For Si: mi*...

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For Ge: mL 1.59m, and mr* = 0.0823mo For GaAs: me* = 0.0665mo For Si: mi* 0.9163m, and mr* = 0.1905mo The room temperature electron mobility of n-type Ge, Si, and GaAs samples doped to 2x107 cm are 2750, 600, and 4000 cm/V's, respectively. (A) Calculate the average relaxation time, t, (scattering probability = 1/t) for Ge, Si, and GaAs. (B) Assuming at room temperature the dominant scattering mechanisms in elemental semiconductors are due to lattice scatterings. The scattering due to optical phonons for Ge can be approximated as Hop = 900 (300) [exp (hopp) - 1]. The LO phonon frequency, wop, for Ge is 6 THz. Calculate the kT lattice scattering mobility, u. (C) Although Ge and GaAs have a similar average relaxation time, the mobility difference is quite large. Comment on the room temperature mobility difference between Ge and GaAs. For Ge: mL 1.59m, and mr* = 0.0823mo For GaAs: me* = 0.0665mo For Si: mi* 0.9163m, and mr* = 0.1905mo The room temperature electron mobility of n-type Ge, Si, and GaAs samples doped to 2x107 cm are 2750, 600, and 4000 cm/V's, respectively. (A) Calculate the average relaxation time, t, (scattering probability = 1/t) for Ge, Si, and GaAs. (B) Assuming at room temperature the dominant scattering mechanisms in elemental semiconductors are due to lattice scatterings. The scattering due to optical phonons for Ge can be approximated as Hop = 900 (300) [exp (hopp) - 1]. The LO phonon frequency, wop, for Ge is 6 THz. Calculate the kT lattice scattering mobility, u. (C) Although Ge and GaAs have a similar average relaxation time, the mobility difference is quite large. Comment on the room temperature mobility difference between Ge and GaAs.

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A The average relaxation time tau can be calculated using the formula mu qtaum where mu is the mobil... View the full answer