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Question 12.2: Calculate the base transport factor. Assume transistor param...

Calculate the base transport factor.

Assume transistor parameters of x_{B}=0.80 \mu \mathrm{m} and L_{B}=10.0 \mu \mathrm{m}.

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From Equation (12.39a), we find

\alpha_{T} \approx \frac{1}{\cosh \left(x_{B} / L_{B}\right)}     (12.39a)

\alpha_{T} \cong \frac{1}{\cosh \left(\frac{x_{B}}{L_{B}}\right)}=\frac{1}{\cosh \left(\frac{0.80}{10.0}\right)}=0.9968

Comment

This simple example shows a typical magnitude of the base transport factor.

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