question_answer

Within depletion region of p-n junction of diode:

A)  p-side is positive and n-side negative

B)  p-side is negative and n-side is positive

C)  both side positive or both negative

D)  both side neutral

Correct Answer: B

Solution :

 In a p-n junction diode, electrons in conduction band on n-type side travel across the junction and leave the positively ionized impurity atoms unneutralised. Consequently, there is positively charged region adjacent to the junction in n-type material. On n-type side the electrons which have traversed the boundary recombine with positive holes in the valence band and form a layer of Unneutralised negatively ionized trivalenf impurity atoms making a negatively charge region as shown in figure. The region around the junction is called charge depletion region or space charge region. Hence, within the depletion region, p-side is negative and n-side is positive.