Carrier transport in semiconductor

AI Thread Summary
In intrinsic GaAs, the electron and hole mobilities are 0.85 and 0.04 m²/V·s, with effective masses of 0.068m and 0.5m, respectively. The band gap energy is 1.43 eV at 300K. To calculate intrinsic carrier concentration, the relevant formula involves effective masses, temperature, and energy gap, expressed as intrinsic carrier concentration = (2.33 x 10^43) * (Mn * Mp / M²)^(3/2) * (T³) * e^(-Eg/kT). Conductivity can then be determined using the formula σ = e(nμn + pμp), where n and p are the carrier concentrations. The discussion seeks clarification on the relationship between mobility, carrier concentration, and effective mass.
RajChakrabrty
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Homework Statement



in Intrinsic GaAs,electron and hole mobility are 0.85 and 0.04 meter square/volt-sec
and corresponding effective mass are 0.068m and 0.5m, where m=9.11*10^(-31)kg.
band gap energy is 1.43 eV at 300K.
---calculate intrinsic carrier concentration(!) and Conductivity.

Homework Equations


the eqs I know related with mobility are;
mu=v/F=e*tau/m(eff)
conductivity=e(n*mu[n]+p*mu[p]).
mu=mobility
e=charge of carrier(say electron)

The Attempt at a Solution



but what are the formulae to relate between mobility,carrier concentration using
effective mass?
if carrier concentration is calculated, then conductivity=e(n*mu[n]+p*mu[p]).

please help me.anyone.
 
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intrinsic carrier concentration=(2.33 * (10)^43) * ( ..(.. (Mn*Mp) / (M^2).. ) ^(3/2).. ) * (T ^3) * (e ^ (-Eg/kT) )
Mn=effective mass of electron
Mp=effective mass of hole
M=mass of electron
T=temperature in kelvin
Eg=energy gap at particular T
k=boltzman constant
e=mathametical constant e.
i kept dots between bracket so as to make it easy to identify,those dots have nothing to do with the formula..
 
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