The saturation current density of a $$P-N$$ junction germanium diode is $$250mA/m2$$ at $$300$$ K. Find the voltage $$($$ in V $$)$$ that would have to be applied across the junction to cause a forward current density $$105A/m2$$ to flow. $$($$ $$K=1.38$$×$$10$$−$$23$$ $$J/K)$$

Question

The saturation current density of a $$P-N$$ junction germanium diode is $$250mA/m2$$  at $$300$$ K. Find the voltage $$($$ in  V $$)$$ that would have to be applied across the junction to cause a forward current density  $$105A/m2$$ to flow. $$($$ $$K=1.38$$×$$10$$−$$23$$ $$J/K)$$

Infinity Learn · Accepted Answer

The current in the junction diode is given by $$I=IS(eeV$$ηKT−$$1)$$      For  Ge     η$$=1Dividing$$ by $$cross-section$$ area, we get $$J=JS(eeVKT$$−$$1)$$      →(1) Put $$JS=250mA/m2$$   $$=250$$×$$10$$−$$3A/m2$$ $$J=105A/m2$$,    $$T=300$$ KAfter solving (1) ,  JJs $$+1$$ $$=$$ eeVKT⇒lnJJs $$+1$$ $$=eVKT$$ ⇒V $$=$$ KTe lnJJs $$+1$$⇒V $$=$$ $$1.38$$×$$10$$−$$23$$×$$3001.6$$×$$10-19$$ $$ln105250$$×$$10$$−$$3$$ $$+1$$⇒V $$=$$ $$258.75$$×$$10-4$$ ×$$12.899=0.33$$ V

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The saturation current density of a P-N junction germanium diode is $250 m A / m^{2}$ at 300 K. Find the voltage ( in V ) that would have to be applied across the junction to cause a forward current density $10^{5} A / m^{2}$ to flow. ( $K = 1.38 \times 10^{- 23} J / K$ )

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Diodes

Remember concepts with our Masterclasses.

The saturation current density of a P-N junction germanium diode is 250mA/m2 at 300 K. Find the voltage ( in V ) that would have to be applied across the junction to cause a forward current density 105A/m2 to flow. ( K=1.38×10−23 J/K)

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The saturation current density of a P-N junction germanium diode is $250 m A / m^{2}$ at 300 K. Find the voltage ( in V ) that would have to be applied across the junction to cause a forward current density $10^{5} A / m^{2}$ to flow. ( $K = 1.38 \times 10^{- 23} J / K$ )