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Why is that a space charge region in a pn junction at equilibrium is often made small?
Wiki User
∙ 14y ago
The space charge region in a pn junction at equilibrium is often made small due to:
- to obtain a high junction capacitance;
since the junction capacitance is inversely proportional to the width of the space charge region, the smaller the width, the larger the junction capacitance.
- to ensure easy diffusion of charge carriers;
if the space charge region is made small, that is, the width is made small, the distance for diffusion also becomes short, then it becomes easy for the electrons to diffuse into the p-side and the holes into the n-side
Wiki User
∙ 14y ago
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