Semi Conductors Objectives Part 04
61 .
62 . In a N-type semi-conductor, the concentration of minority carriers mainly depends on the temperature of the material.
63 . When a semi-conductor is doped, its electrical conductivity increases.
64 . When a normal atom loss an electron, the atom become a positive ion.
65 . Resistivity is a property of a semiconductor that depends on the shape of the semiconductor.
66 . An electrically neutral semiconductor has equal number of positive and negative charges.
67 . The electron in the outermost orbit is called valence electrons.
68 . The semi-conductors have negative temperature coefficient of resistance.
69 . The larger the orbit, the greater is the energy of the electrons.
70 . In N-type semiconductors free electrons are the majority carriers.
71 . The merging of a free electron and a hole is called recombination.
72 . Excess minority carriers are the carriers that are in excess of the equilibrium number.
73 . A PN-junction offers conducts in forward direction only.
74 . When a PN junction is unbiased, the junction current at equilibrium is mainly due to the diffusion of majority carriers.
75 . At a PN-junction, the potential barrier is due to the charges on either side of the junction, which consists of fixed donors and acceptor ions.
76 . In PN junction, the region containing the uncompensated acceptor and donor ions is called depletion region.
77 . A PN junction is said to be forward biased when positive terminal of battery connected to P-side and negative side to the N-side.
78 . When PN-junction is in forward bias, by increasing the battery voltage current through PN-junction increase.
79 . Figure A represents the V-I characteristics of a PN-junction.
80 . In a reverse biased P-N junction, the current through the junction increases abruptly at breakdown voltage.
