What term describes the semiconductor operation condition in which a low-resistance state exists?

What term describes the semiconductor operation condition in which a low-resistance state exists?

• A. Reverse bias
• B. Forward bias
• C. Saturation
• D. Cutoff

Answer: (B)

When a PN junction is forward biased, the external voltage lowers the barrier at the junction and narrows the depletion region, allowing a large number of charge carriers to cross. This causes the current to rise quickly with only a small increase in voltage, so the junction behaves as a low-resistance path in that conducting state. In reverse bias, the depletion region expands and carriers are blocked, keeping the current very small and the path high resistance. Saturation and cutoff are terms more related to transistor operation states, not the basic diode conduction; for a diode, the low-resistance condition is achieved under forward bias.

When a PN junction is forward biased, the external voltage lowers the barrier at the junction and narrows the depletion region, allowing a large number of charge carriers to cross. This causes the current to rise quickly with only a small increase in voltage, so the junction behaves as a low-resistance path in that conducting state. In reverse bias, the depletion region expands and carriers are blocked, keeping the current very small and the path high resistance. Saturation and cutoff are terms more related to transistor operation states, not the basic diode conduction; for a diode, the low-resistance condition is achieved under forward bias.