When a P-type semi-conductor is heated: (A) number of holes increases while that of electrons decreases (B) number of electron increases while that of hole decreases (C) number of electrons and holes remains same (D) number of electrons and holes increases equally

A P-type semiconductor is characterized by the presence of more holes (positively charged) compared to free electrons (negatively charged). This is because it is doped with an impurity that has one less electron than the host material.

When any semiconductor is heated, the thermal energy causes the creation of more electron-hole pairs. In other words, the number of free electrons and holes will increase due to the extra energy. However, in a P-type semiconductor, holes are the majority charge carriers, while free electrons are minority charge carriers.

(A) - If only the number of holes increases and the number of electrons decreases, it would mean that the heating results in an imbalance between the majority and minority carriers. This is not the case, as both numbers should increase. (B) - This option suggests that the number of electrons increases while the number of holes decreases, which implies that the material becomes balanced or even N-type. This is not accurate, as heating should generate more electron-hole pairs, not change the type of material. (C) - This option states that the number of electrons and holes remains the same upon heating, which is incorrect because heating should cause the generation of more electron-hole pairs. (D) - This option correctly states that the number of electrons and holes will increase equally upon heating. This maintains the overall balance between the majority and minority charge carriers while accounting for the effect of heating on the material. Therefore, the correct answer is (D): the number of electrons and holes increases equally when a P-type semiconductor is heated.