The barrier potential of a \(\mathrm{p\text{-}n}\) junction depends on:
(a) | type of semiconductor material |
(b) | amount of doping |
(c) | temperature |
Which one of the following is correct?
1. (a) and (b) only
2. (b) only
3. (b) and (c) only
4. (a), (b) and (c)
1. | Electrons are minority carriers and pentavalent atoms are dopants. |
2. | Holes are minority carriers and pentavalent atoms are dopants. |
3. | Holes are the majority carriers and trivalent atoms are dopants. |
4. | Electrons are the majority carriers and trivalent atoms are dopants. |
The output \((X)\) of the logic circuit shown in the figure will be:
1. \(X= \overline{A\cdot B}\)
2. \(X = A\cdot B\)
3. \(X= \overline{A+ B}\)
4. \(X=\overline{\overline{A}} \cdot \overline{\overline{B}}\)
Two ideal diodes are connected to a battery as shown in the circuit. The current supplied by the battery is:
1. \(0.75~\text{A}\)
2. zero
3. \(0.25~\text{A}\)
4. \(0.5~\text{A}\)
1. | in the case of \(C\), the valence band is not completely filled at absolute zero temperature. |
2. | in the case of \(C\), the conduction band is partly filled even at absolute zero temperature. |
3. | the four bonding electrons in the case of \(C\) lie in the second orbit, whereas in the case of \(Si\), they lie in the third. |
4. | the four bonding electrons in the case of \(C\) lie in the third orbit, whereas for \(Si\), they lie in the fourth orbit. |
The figure shows a logic circuit with two inputs \(A\) and \(B\) and the output \(C\). The voltage waveforms across \(A\), \(B\), and \(C\) are as given. The logic circuit gate is:
1. \(\text{OR}\) gate
2. \(\text{NOR}\) gate
3. \(\text{AND}\) gate
4. \(\text{NAND}\) gate
The symbolic representation of four gates is shown as:
Pick out which ones are for AND, NAND, and NOT gates, respectively.
1. (i), (iv), and (iii)
2. (ii), (iii), and (iv)
3. (ii), (iv), and (iii)
4. (ii), (iv), and (i)
1. | the antimony becomes an acceptor atom |
2. | there will be more free electrons than holes in the semiconductor |
3. | its resistance is increased |
4. | it becomes a \(p\small{-}\)type semiconductor |
1. | the positive terminal of the battery is connected to the p-side and the depletion region becomes thick. |
2. | the negative terminal of the battery is connected to the n-side and the depletion region becomes thin. |
3. | the positive terminal of the battery is connected to the n-side and the depletion region becomes thin. |
4. | the negative terminal of the battery is connected to the p-side and the depletion region becomes thick. |
Which one of the following statements is false?
1. | Pure Si doped with trivalent impurities gives a p-type semiconductor. |
2. | The majority of carriers in an n-type semiconductor are holes. |
3. | The minority carriers in a p-type semiconductor are electrons. |
4. | The resistance of intrinsic semiconductors decreases with an increase in temperature. |