Question

A Si p+n junction Consider an abrupt Si p+n junction which has 2 x 10^15 donors cm-3 on the n-side and 5 x 10^17 acceptors on the p-side. The minority carrier recombination times are ?h ? 400 ns for holes in the n-side and ?e ? 50 ns for electrons in the p+-side. The cross sectional area is 0.1 mm2. Assume a long diode. The thermal generation time ?g in the depletion region is 2 ?s. Assume that the reverse current is dominated by the thermal generation rate in the depletion region. (a) Calculate the forward current at 27 °C when the voltage across the diode is 0.6 V. (b) Estimate the forward current at 57 °C when the voltage across the diode is still 0.6 V. (c) Calculate the voltage across the diode at 57 °C if the forward current in (a) at 27 °C is kept constant. (d) What is the reverse current at 27 °C when the diode voltage is -5 V? (e) Estimate the reverse current at 57 °C when the diode voltage is -5 V. Note: Assume that the forward current is determined by the Shockley equation (minority carrier diffusion).

          A Si p+n junction Consider an abrupt Si p+n junction which has 2 x 10^15 donors cm-3 on the n-side and 5 x 10^17 acceptors on the p-side. The minority carrier recombination times are ?h ? 400 ns for holes in the n-side and ?e ? 50 ns for electrons in the p+-side. The cross sectional area is 0.1 mm2. Assume a long diode. The thermal generation time ?g in the depletion region is 2 ?s. Assume that the reverse current is dominated by the thermal generation rate in the depletion region. (a) Calculate the forward current at 27 °C when the voltage across the diode is 0.6 V. (b) Estimate the forward current at 57 °C when the voltage across the diode is still 0.6 V. (c) Calculate the voltage across the diode at 57 °C if the forward current in (a) at 27 °C is kept constant. (d) What is the reverse current at 27 °C when the diode voltage is -5 V? (e) Estimate the reverse current at 57 °C when the diode voltage is -5 V. Note: Assume that the forward current is determined by the Shockley equation (minority carrier diffusion).

A Si p+n junction Consider an abrupt Si p+n junction which has 2 x 10^15 donors cm-3 on the n-side and 5 x 10^17 acceptors on the p-side. The minority carrier recombination times are ?h ? 400 ns for holes in the n-side and ?e ? 50 ns for electrons in the p+-side. The cross sectional area is 0.1 mm2. Assume a long diode. The thermal generation time ?g in the depletion region is 2 ?s. Assume that the reverse current is dominated by the thermal generation rate in the depletion region. (a) Calculate the forward current at 27 °C when the voltage across the diode is 0.6 V. (b) Estimate the forward current at 57 °C when the voltage across the diode is still 0.6 V. (c) Calculate the voltage across the diode at 57 °C if the forward current in (a) at 27 °C is kept constant. (d) What is the reverse current at 27 °C when the diode voltage is -5 V? (e) Estimate the reverse current at 57 °C when the diode voltage is -5 V. Note: Assume that the forward current is determined by the Shockley equation (minority carrier diffusion).

Added by Miriam E.

Question

Please give Ace some feedback