146. In an intrinsic semiconductor, the number of free electrons ……..
(a) equals the number of holes
(b) is greater than the number of holes
(c) is less than the number of holes
(d) none of the above
147. At room temperature, an intrinsic semiconductor has ……..
(a) many holes only
(b) a few free electrons and holes
(c) many free electrons only
(d) no holes or free electrons
148. At absolute temperature, an intrinsic semiconductor has ……..
(a) a few free electrons
(b) many holes
(c) many free electrons
(d) no holes or free electrons
149. At room temperature, an intrinsic silicon crystal acts approximately as ……..
(a) a battery
(b) a conductor
(c) an insulator
(d) a piece of copper wire
150. P-type semiconductors are :
(a) +very charged
(b) Electrically neutral
(c) Obtained when phosphorus is added as impurity to silicon or germanium
(d) Obtained when arsenic is added as impurity to germanium or silicon
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Semiconductor Materials » Exercise - 3129. Addition of trivalent impurity to a semiconductor creates many ........ (a) holes (b) free electrons (c) valence electrons (d) bound electrons- Semiconductor Materials » Exercise - 299. Addition of pentavalent impurity to a semiconductor creates many ........ (a) free electrons (b) holes (c) valence electrons (d) bound electrons
- Semiconductor Materials » Exercise - 4159. The addition of pentavalent impurity to a semiconductor creates more : (a) Free electrons (b) Holes (c) Positrons (d) Free electrons and holes
- Semiconductor Materials » Exercise - 3148. At absolute temperature, an intrinsic semiconductor has ........ (a) a few free electrons (b) many holes (c) many free electrons (d) no holes or free electrons
- Semiconductor Materials » Exercise - 4153. In a substance the conduction band and valence band are separated by a energy gap of the order of 1 eV, and there are at room temperature as money electrons in the conduction band as holes in the valence band. The substance is : (a) An intrinsic semiconductor (b) A p-type semiconductor (c) A N-type semiconductor (d) A doped semiconductor