Determine the total carrier recombination lifetime of a double heterojunction LED where the radioactive and nonradioactive recombination lifetime of minority carriers in active region are 70 ns and 100 ns respectively.
A)41.17 ns
B)35 ns
C)40 ns
D)37.5 ns

Question

Quizplus · Accepted Answer

The total carrier recombination lifetime ($ \tau_{total} $) in a semiconductor can be calculated using the formula for parallel processes: $\frac{1}{\tau_{total}} = \frac{1}{\tau_{radiative}} + \frac{1}{\tau_{nonradiative}}$, where $ \tau_{radiative} $ is the radiative recombination lifetime and $ \tau_{nonradiative} $ is the nonradiative recombination lifetime. Substituting the given values, $ \frac{1}{\tau_{total}} = \frac{1}{70 ns} + \frac{1}{100 ns} = \frac{1}{41.17 ns} $, thus $ \tau_{total} = 41.17 ns $.

Determine the Total Carrier Recombination Lifetime of a Double Heterojunction