Semiconductor Electronics — practice questions
109 curated practice questions from Semiconductor Electronics (Physics Class 12, CBSE) — 26 medium, 83 easy. Every question includes the final answer free; step-by-step worked solutions with a free account.
- Pieces of copper and of silicon are initially at room temperature. Both are heated to temperature T. The conductivity of
- In an extrinsic semiconductor, the number density of holes is 4 10 20 m -3 . If the number density of intrinsic…
- Germanium crystal is doped at room temperature with a minute quantity of boron. The charge carriers in the doped…
- The Fermi level of an intrinsic semiconductor is pinned at the centre of the band gap. The probability of occupation of…
- A potential barrier of 0.50 V exists in a p-n junction. If the depletion region is 5.0 × 10 –7 m thick, what is the…
- Study the circuit shown in the figure. Name the gate that the given circuit resembles.
- In a circuit as shown in the figure, if the diode forward voltage drop is 0.3 V, the voltage difference between A and B…
- In forward bias, the width of a potential barrier in a p-n junction diode
- A potential barrier of 0.3 V exists across a p - n junction. If the depletion region is 1 m m wide, what is the…
- In the half wave rectifier circuit shown which one of the following wave forms is true for V CD , the output across C…
- Assertion(A): We cannot form a p-n junction diode by taking a slab of a p-type semiconductor and physically joining it…
- In the case of forward biasing of p-n junction, which one of the following figures correctly depicts the direction of…
- Two identical p-n junctions may be connected in series with a battery in three ways as shown. The potential drops…
- At 0 K, the resistivity of an intrinsic semiconductor is:
- In the circuit given, the current through the zener diode is
- In an n-type semiconductor, the donor energy level lies
- A semiconductor device is connected in series with a battery, an ammeter and a resisitor. A current flows in the…
- At a certain temperature in an intrinsic semiconductor, the electrons and holes concentration is 1.5 10 16 m -3 . When…
- Junction Diode as a Rectifier: The process of conversion of an ac voltage into a dc voltage is called rectification and…
- The maximum wavelength of electromagnetic radiation, which can create a hole-electron pair in germanium. (Given that…
- Which one of the following statements is FALSE? Pure Si doped with trivalent impurities gives a p-type semiconductor…
- Carbon, silicon and germanium have four valence electrons each. These are characterised by valence and conduction bands…
- p -type semiconductors are formed when Si or Ge are doped with
- The Fermi level in an intrinsic semiconductor at 0 K temperature lies
- 40. Which of the following circuits provides full wave rectification of an ac input?
- The logic circuit shown below has the input waveforms A and B as shown. Pick out the correct output waveform.
- Suitable impurities are added to a semiconductor depending on its use. This is done to
- An n-type semiconducting Si is obtained by doping intrinsic Si with:
- Junction Diode as a Rectifier: The process of conversion of an ac voltage into a dc voltage is called rectification and…
- The dominant mechanism for motion of charge carriers in forward and reverse biased silicon p - n junction are
- The energy required by an electron to jump the forbidden band in silicon at room temperature is about
- The manifestation of band structure in solids is due to
- In case of a p-n junction diode at high value of reverse bias, the current rises sharply. The value of reverse bias is…
- If a small amount of antimony is added to germanium crystal
- Assertion (A): A hole is an apparent free particle with effective positive electronic charge. Reason (R): A hole is not…
- Assertion (A): A photocell is called an electric eye. Reason (R): When light is incident on some semiconductor, its…
- When the resistance measured between p and n ends of a p-n junction diode is high, it can act as a/an-
- Assertion (A): In a semiconductor, the electrons in the conduction band have lesser energy than those in the valence…
- The given graph represents the I-V characteristics of a Zener diode. Which part of the characteristics curve is most…
- When an intrinsic semiconductor is doped with a small amount of trivalent impurity, then:
- In the following figures, which one of the diodes is reverse biased?
- A sinusoidal voltage of rms value 220 V is applied to a diode and a resistor R in the circuit shown in figure, so that…
- The conductivity of intrinsic semiconductors can be increased by adding a suitable impurity. This process is called ( P…
- Si is doped with a pentavalent element. The energy required to set the additional electron free is about:
- The threshold voltage for a p-n junction diode used in the circuit is 0.7 V. The type of biasing and current in the…
- At equilibrium, in a p-n junction diode the net current is
- Which of the following statements is true about semiconductors?
- If a small amount of antimony is added to germanium crystal
- The given graph represents V - I characteristic for a semiconductor device. Which of the following statement is correct?
- Assertion (A): Silicon is preferred over germanium for making semiconductor devices. Reason (R): The energy gap for…
- Assertion (A): In insulators, the forbidden gap is very large. Reason (R): The valence electrons in an atom of an…
- When the voltage drop across a p - n junction diode is increased from 0.65 V to 0.70 V, the change in the diode current…
- If a zener diode ( V Z = 5 V and I Z = 10 mA) is connected in series with a resistance and 20 V is applied across the…
- For the forward biasing of a p-n junction diode, which of the following statements is not correct?
- Which type of semiconductor is formed when germanium is doped in the gallium as indicated in the figure?
- Which is the correct diagram of a half-wave rectifier ?
- Assertion (A): The temperature coefficient of resistance is positive for metals and negative for p-type semiconductors…
- To get n -type of semiconductor, Germanium should be doped with
- Assertion (A): The impurities in p-type Si are not pentavalent atoms. Reason (R) : The hole density in valance band in…
- In the energy-band diagram of n-type Si, the gap between the bottom of the conduction band E C and the donor energy…
- In the given Fig., V o is the potential barrier across a p-n junction, when no battery is connected across the junction
- Three photo diodes D 1 , D 2 and D 3 are made of semiconductors having band gap of 2.5 eV, 2 eV and 3 eV, respectively…
- A pure Si crystal having 5 10^ 28 atoms m ^ -3 is dopped with 1 ppm concentration of antimony. If the concentration of…
- In a p-type semiconductor, the majority carriers of current are
- In the given Fig., assuming the diodes to be ideal,
- A semiconductor has equal electron and hole concentration of 6 × 10 8 per m 3 . On doping with certain impurity…
- The output current I versus time (t) curve of a full wave rectifier is shown in the figure. The average value of the…
- A p-n photodiode is fabricated from a semiconductor with a band gap of 2.5 eV. The signal wavelength is
- The majority charge carriers in p -type semiconductor are
- Mobilities of electrons and holes in a sample of intrinsic germanium at room temperature are 0.54 m 2 V –1 s –1 and…
- Assertion (A): In n type semiconductor, number density of electrons is greater than the number density of holes but the…
- Which of the energy band diagrams shown below corresponds to that of a semiconductor ?
- Junction Diode as a Rectifier: The process of conversion of an ac voltage into a dc voltage is called rectification and…
- The circuit shown in the figure contains two diodes each with a forward resistance of 30 Ω and with infinite backward…
- If in a p-n junction, a square input signal of 10 V is applied as shown, then the output across R L will be
- The probability of electrons to be found in the conduction band of an intrinsic semiconductor of finite temperature
- The circuit shown in figure acts as
- Assertion(A): In a semiconductor diode the thickness of depletion layer is not fixed. Reason (R): Thickness of…
- Choose the only false statement from the following: In conductors the valence and conduction bands overlap Substances…
- In a full wave junction diode rectifier the input ac has rms value of 20 V. The transformer used is a step up…
- Assertion (A): Diffusion current in a p-n junction is greater than the drift current in magnitude if the junction is…
- Which of the following is an electrical conductor at room temperature?
- The following table provides the set of values of V and I obtained for a given diode. Let the characteristics α be…
- In a half wave rectifier circuit operating from 50 Hz mains frequency, the fundamental frequency in the ripple would be
- Find the wavelength of light that may excite an electron in the valence band of diamond to the conduction band. The…
- Junction Diode as a Rectifier: The process of conversion of an ac voltage into a dc voltage is called rectification and…
- When intrinsic silicon semiconductor is doped with Al atom, then it:
- In an n -type silicon, which of the following statements is true.
- In which of the following diagrams is the capacitor C connected correctly to provide smooth output of a half-wave…
- The electrical conductivity of a semiconductor increases when electromagnetic radiation of wave length shorter than…
- Assertion (A): n-type semiconductor is not negatively charged. Reason (R): Neutral pentavalent impurity atom doped in…
- The V - I characteristic of a silicon diode is shown in figure. The resistance of the diode at I D = 15 mA is
- In the following figure, the diodes which are forward biased, are
- In the circuit shown in figure if the current through the 500 W resistor is 25 mA and that through the load R L is 5…
- In the circuit shown if drift current for the diode is 20 μA, the potential difference across the diode is
- Solids having highest energy level partially filled with electrons are
- The formation of depletion region in a p-n junction diode is due to
- Which of the following devices is sometimes called an electric eye ?
- If the energy of a photon of sodium light ( = 589 nm) equals the band gap of a semiconductor, the minimum energy…
- Which of the junction diodes shown below are forward biased?
- Assertion (A): The electrical conductivity of a pure Ge crystal increases with increase in its temperature. Reason (R)…
- Assertion (A): The resistance of an intrinsic semiconductor decreases with increase in its temperature. Reason (R): The…
- Junction Diode as a Rectifier: The process of conversion of an ac voltage into a dc voltage is called rectification and…
- With an ac input from 50 Hz power line, the ripple frequency is
- Which of the following statements is not true for a p-n junction diode under reverse bias?
- When the voltage drop across a p- n junction diode is increased from 0.65 V to 0.70 V, the change in the diode current…
- In the energy band diagram of a material as given below, the open circles and filled circles denote holes and electrons…
- In the half-wave rectifier circuit shown, which one of the following wave form is true for V CD , the output across C…
- A p - n photodiode is made of a material with a band gap of 2 eV. The minimum frequency of the radiation that can be…