For the electrons in silicon, we have:
a) The drift velocity of electrons at room temperature is 70 m/s.
b) The time that takes an electron to traverse a 25-mm length of crystal is 3.57x10⁻⁴ s.
a) The drift velocity of electrons can be calculated with the following equation:
[tex] v = \mu_{e} E [/tex]
Where:
[tex]\mu_{e}[/tex]: is the electrons mobility = 0.14 m²/V*s (at room tempearture)
E: is the electric field = 500 V/m
Hence, the drift velocity is:
[tex] v = \mu_{e} E = 0.14 m^{2}/(V*s)*500 V/m = 70 m/s [/tex]
b) The time that takes an electron to traverse a 25-mm length of crystal is the follows:
[tex] t = \frac{d}{v} [/tex]
Where:
d: is the distance = 25 mm = 0.025 m
So, the time is:
[tex] t = \frac{d}{v} = \frac{0.025 m}{70 m/s} = 3.57 \dot 10^{-4} s [/tex]
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