4. a) For a pn junction if Na«Na, draw the diagram of depletion region, space charge density and electric field in space charge region. b) In a p-type Si bar with cross sectional area is 0.5cm² and major carrier concentration 10 cm-3 at x = 0. What is the steady state separation between F, and Ec at x = 10¬º. What is the hole current if there is no electric field? assume that hole mobility is 500cm² /Vs and life time for holes is 10–10, S.

4. a) For a pn junction if Na«Na, draw the diagram of depletion region, space charge density and electric field in space charge region. b) In a p-type Si bar with cross sectional area is 0.5cm² and major carrier concentration 10 cm-3 at x = 0. What is the steady state separation between F, and Ec at x = 10¬º. What is the hole current if there is no electric field? assume that hole mobility is 500cm² /Vs and life time for holes is 10–10, S.