Electrical – Effect of base doping on early voltage,base transport factor and emitter injection efficiency

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According to me as base doping increases recombination will be less at base region so base transport factor and emitter injection efficiency will increase and as effective base width will decrease due to less doping at the base region so early voltage will decrease.
am I thinking right? No options is matching.

Best Answer

First of all you have a typing error in your analysis,
"According to me as base doping increases ..."
Here, it should be decreases and rest are fine;

And yes your conclusion is right ,
i.e,
$$ \text{as } \quad N_B \downarrow \quad \to \quad \gamma \text{ (Emitter Injection Efficiency) } \uparrow \quad, \quad \beta^{*} \,\, \uparrow \,\,\& \,\,|V_A| \,\,\downarrow $$