Questions
EESM5200 (L1) Part I: Topic 6 - Carrier Actions in a PN Junction
Single choice
Assume you have a P+/N junction that both the P+ side and the N side are short. Which of the following change (which assume the diode remains as a short P+/N diode after the change) will lead to the highest increase in current
Options
A.increase the P+ region length
B.reduce the P+ region length
C.increase the N region length
D.reduce the N region length
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Step-by-Step Analysis
When analyzing a P+/N junction that is effectively shorted (the diode behaves like a short circuit across the junction), the current is primarily governed by the series resistance along the current path through the doped regions. Changing the physical length of the conducting regions changes this series resistance.
Option 1: increase the P+ region length. Making the heavily doped P+ side longer increases the distanc......Login to view full explanationLog in for full answers
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