1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
trapecia [35]
3 years ago
12

Explain concept of donor levels and accepter levels in extrinsic semiconductors and How can Fermi level be defined for conductor

s , insulators and semiconductors when temperature increases above zero Kelvin.
Physics
1 answer:
nika2105 [10]3 years ago
5 0

Answer:

DONORS: If the material for which it substitutes has more electrons than the original

ACCEPTORS: If the replacement material has fewer electrons than the original material

Fermi level: the point where the probability of finding the last electron is ½

Explanation:

When in a semiconductor material a small fraction of an element is replaced by another with different valences, an excess charge is created.

If the material for which it substitutes has more electrons than the original, there is an excess of electrons, these excess electrons are weakly bound in the material and their orbits are large, in an energy versus moment diagram their energy places them a little more below the conduction band, these materials are called DONORS.

If the replacement material has fewer electrons than the original material, one electron is missing to complete the bonds, so there is a movement of the other electrons, an easier way to analyze this movement of the (n-1) electrons is to suppose that The missing charge has a positive charge and to study its movement, this positive charge is called a hole, its binding energy is small so the orbit of the hole is large, in an energy diagram it is located a little above the band of valence, these are called ACCEPTORS

The Fermi level is defined as the point where the probability of finding the last electron is ½, when the temperature is changed the density of states of the bands changes, therefore the location point moves, but its [probability remains ½

You might be interested in
What type of nuclear decay releases energy but not a particle?
statuscvo [17]
I believe gamma decay but i may be wrong
7 0
2 years ago
Read 2 more answers
If an object placed in a fluid experiences a buoyant force equal to the weight of the fluid it displaces, the object will float.
enyata [817]

Answer: The answer is False

Explanation: This is for the one's in apex <>

6 0
3 years ago
How much heat is required to evaporate 0.15 kg of lead at 1750°C, the boiling point for lead? The heat of vaporization for lead
lara [203]

Answer:

Heat required = mass× latent heat Q = 0.15 × 871 ×

3 0
2 years ago
A Ferris wheel on a California pier is 27 m high and rotates once every 32 seconds in the counterclockwise direction. When the w
Leto [7]

A) 140 degrees

First of all, we need to find the angular velocity of the Ferris wheel. We know that its period is

T = 32 s

So the angular velocity is

\omega=\frac{2\pi}{T}=\frac{2\pi}{32 s}=0.20 rad/s

Assuming the wheel is moving at constant angular velocity, we can now calculate the angular displacement with respect to the initial position:

\theta= \omega t

and substituting t = 75 seconds, we find

\theta= (0.20 rad/s)(75 s)=15 rad

In degrees, it is

15 rad: x = 2\pi rad : 360^{\circ}\\&#10;x=\frac{(15 rad)(360^{\circ})}{2\pi}=860^{\circ} = 140^{\circ}

So, the new position is 140 degrees from the initial position at the top.

B) 2.7 m/s

The tangential speed, v, of a point at the egde of the wheel is given by

v=\omega r

where we have

\omega=0.20 rad/s

r = d/2 = (27 m)/2=13.5 m is the radius of the wheel

Substituting into the equation, we find

v=(0.20 rad/s)(13.5 m)=2.7 m/s

6 0
3 years ago
What is the period of a wave that has a frequency of 300 hz?
Butoxors [25]

Answer:

T = 0.003 s

(Period is written as T)

Explanation:

Period = time it takes for one wave to pass (measured in seconds)

frequency = number of cycles that occur in 1 second

(measured in Hz / hertz / 1 second)

Period : T

frequency : f

So, if we know that the frequency of a wave is 300 Hz, we can find the period of the wave from the relation between frequency and period

T =  \frac{1}{f}    f = \frac{1}{T}

to find the period (T) of this wave, we need to plug in the frequency (f) of 300

T = \frac{1}{300}

T = 0.00333333333

So, the period of a wave that has a frequency of 300 Hz is 0.003 s

[the period/T of this wave is 0.003 s]

3 0
1 year ago
Other questions:
  • Beginning with earth, summarize the structure of the universe. Also Andromeda galaxy is located appromaxily 2.5 million light-ye
    11·1 answer
  • Label the three forms of energy represented in this image
    6·2 answers
  • A 68.5 kg astronaut is doing a repair in space on the orbiting space station. she throws a 2.25 kg tool away from her at 3.20 m/
    6·1 answer
  • If the thrower takes 0.90 s to complete one revolution, starting from rest, what will be the speed of the discus at release?
    7·1 answer
  • Which kind of energy is fire? A. kinetic B. potential C. nuclear D. latent
    6·2 answers
  • A box is pushed across a horizontal table at constant speed. Of the forces on it, which pair do we know are equal in magnitude b
    14·1 answer
  • Which one of the following situations is not possible?
    6·1 answer
  • What is the color and frequency of the light that is produced? 1 nm = 1 x 10^-7 meters and the speed of light (c) = 3.0 x 10^8 m
    8·1 answer
  • An 80 kg object has a µk = 0.35 and a µs = 0.60. Assuming it is on a flat surface
    14·1 answer
  • HELP ME PLEASEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!