Formation of depletion layer

What causes electrons and holes to start moving when P-type and N-type materials are joined?

• External voltage

• Heat

• Concentration difference

• Pressure

What happens when an electron and a hole meet at the junction?

• They bounce back

• They recombine and cancel each other

• They form a photon

• They generate heat

What is left behind in the junction area after recombination?

• Fixed ions (positive and negative)

• Free electrons and holes

• No particles at all

• Only positive charges

What do these fixed ions create in the depletion region?

• Light

• Sound

• Pressure

• Electric field

In which direction does the electric field point in a PN junction?

• From P to N

• Circular direction

• From N to P

• No specific direction

Why does further movement of electrons and holes stop after the depletion layer forms?

• Electric field opposes further movement

• Junction is broken

• Voltage is too high

• Lack of charge carriers