Physics - Semiconductors Question with Solution | TestHub
A semiconductor X is made by doping a germanium crystal with indium . A second semiconductor Y is made by doping germanium crystal with arsenic . Both are joined end to end and connected to a battery as shown. Which of the following statements is correct?
Options:
Answer:
Solution:
Germanium is a Group 14 element with a valency of 4.
Semiconductor X is doped with Indium (), which is a Group 13 element and a trivalent impurity. Doping a semiconductor with a trivalent impurity creates holes as majority charge carriers, making it a p-type semiconductor. Thus, X is p-type.
Semiconductor Y is doped with Arsenic (), which is a Group 15 element and a pentavalent impurity. Doping with a pentavalent impurity provides extra electrons as majority charge carriers, making it an n-type semiconductor. Thus, Y is n-type.
In the given circuit diagram, the positive terminal of the battery (longer line) is connected to the p-type semiconductor (X), and the negative terminal (shorter, thicker line) is connected to the n-type semiconductor (Y).
When the p-side is connected to a higher potential than the n-side, the p-n junction is forward biased.
Therefore, X is p-type, Y is n-type, and the junction is forward biased.
Answer: X is p-type, Y is n-type and the junction is forward biased.
