126. A pentavalent impurity has …….. valence electrons.
(a) 3
(b) 5
(c) 4
(d) 6
127. An N-type semiconductor is ……..
(a) positively charged
(b) negatively charged
(c) electrically neutral
(d) none of the above
128. A trivalent impurity has …….. valence electrons.
(a) 4
(b) 5
(c) 6
(d) 3
129. Addition of trivalent impurity to a semiconductor creates many ……..
(a) holes
(b) free electrons
(c) valence electrons
(d) bound electrons
130. A hole in a semiconductor is defined as ……..
(a) a free electron
(b) the incomplete part of an electron pair bond
(c) a free proton
(d) a free neutron
Related Posts
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