Download App

Semiconductor Electronic: Material, Devices And Simple Circuits — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsSemiconductor Electronic: Material, Devices And Simple Circuits1 Mark
MCQ
A semiconductor is a material with a small but non$-$zero band gap that behaves as an insulator at absolute zero but allows thermal excitation of electrons into its $.........$ at temperatures that are below its melting point.
  • A
    $\text{HOMO}$
  • B
    Valence band
  • ✓
    Conduction band
  • D
    $\text{LUMO}$
✓

Answer

Correct option: C.
Conduction band
The band gap in case of semiconductors is of order $3−4\  eV.$  At absolute zero, the valence band is filled and conduction band is empty, so it behaves as an insulator. As the temperature is raised, electrons in the valence band gain sufficient energy to overcome the band gap and jump to the conduction band.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from Semiconductor Electronic: Material, Devices And Simple Circuits→Semiconductor Electronic: Material, Devices And Simple Circuits — all question types→Physics STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Three capacitors of capacitances $25 \mu \mathrm{F}, 30 \mu \mathrm{F}$ and $45 \mu \mathrm{F}$ are connected in parallel to a supply of $100$

$V$. Energy stored in the above combination is $\mathrm{E}$. When these capacitors are connected in series to the same supply, the stored energy is $\frac{9}{\mathrm{x}} \mathrm{E}$. The value of $x$ is___________.

→
Assertion : Interference pattern is made by using blue light instead of red light, the fringes becomes narrower.
Reason : In Young’s double slit experiment, fringe width is given by relation $B = \frac{\lambda \mathrm{D}}{\mathrm{d}}$.
→
There is a solid sphere of radius $‘R’$ having uniformly distributed charge throughout it. What is the relation between electric field $‘E’$ and distance $‘r’$ from the centre ( $r$ is less than R ) ?
→
In nuclear reaction $_2H{e^4}{ + _z}{X^A}{ \to _{z + 2}}{Y^{A + 3}} + A,\;A$ denotes
→
Assertion : Annihilation of electron and positron is an example of decay of charges.
Reason : In the process of annihilation an electron and a positron combine to give a gamma particle.
→
In the circuit shown in the figure neglecting source resistance the voltmeter and ammeter reading will respectively be 
→
Two identical glass rods $S_1$ and $S_2$ (refractive index $=1.5$ ) have one convex end of radius of curvature $10 \ cm$. They are placed with the curved surfaces at a distance $d$ as shown in the figure, with their axes (shown by the dashed line) aligned. When a point source of light $P$ is placed inside rod $S _1$ on its axis at a distance of $50 \ cm$ from the curved face, the light rays emanating from it are found to be parallel to the axis inside $S _2$. The distance $d$ is
→
This question has Statement $-1$ and Statement $-2$ . Of the four choices given after the statements, choose the one that best describes the two statements

Statement $-1$ : Sky wave signals are used for long distance radio communication. These signals are in general, less stable than ground wave signals

Statement $-2$ : The state of ionosphere varies from hour to hour, day to day and season to season

→
Three resistances of magnitude $R$ each are connected in the form of an equilateral triangle of side $a$ . The combination is placed in a magnetic field $B = {B_0}{e^{ - \lambda t}}$ perpendicular to its plane. The induced current in the circuit is given by 
→
A nuclear bomb exploded $200 \,km$ above the surface of moon. The sound of explosion on the moon
→