Why the mobility of holes and electrons is different?
Why the mobility of holes and electrons is different?
Holes are created by the elevation of electrons from innermost shells to higher shells or shells with higher energy levels. Since holes are subjected to the stronger atomic force pulled by the nucleus than the electrons residing in the higher shells or farther shells, holes have a lower mobility.
Why do electrons move faster than holes?
Free electrons (those moving from one atom to another) are in the conduction band and holes (the lack of an electron in an orbit) are in the valence band (same link). The conduction band is at a higher energy level than the valence band and that means that things move faster.
How does the mobility of electrons in a conductor change if the potential difference is doubled?
If the potential difference applied across the conductor is doubled, mobility will become half.
Why is the mobility of free electrons greater than that of holes they are light they mutually collide less they require low energy to continue the motion they carry negative energy?
Electrons need less energy to move because they encounter less resistance during their motion than holes. We can also say that, the electron effective mass is often smaller than the hole effective mass, electron mobility is often greater than hole mobility.
Which one has higher mobility electron or hole?
The electron mobilty is often greater than hole mobility because quite often, the electron effective mass is smaller than hole effective mass. The relaxation times are often of the same order of magnitude for electrons and holes and therefore, they do not make too much difference.
Which is faster holes or electrons?
As electrons are of lighter mass than holes so their acceleration are more than that of holes which follow drift velocity inside conductor,making electron move much faster.
Does mobility depends on potential difference?
The potential difference is inversely proportional to the mobility. So If the potential difference is doubled then mobility gets half.
Does mobility depend on potential?
The mobility depends on applied potential difference, length of conductor, number density of charge carriers, current in conductor, area of cross-section of conductor.
Which type of charge has the greatest mobility?
Electrons and holes are mobile charge carriers. The mobility of electrons is 2.5 to 3 times the mobility of holes. The mobility of electrons and holes depends on their effective masses. The effective mass of electrons is less than that of holes hence electrons have higher mobility than holes.
How is hole mobility related to electron mobility?
The ability of an hole to move through a metal or semiconductor, in the presence of applied electric field is called hole mobility.
What is the mobility of electrons in a semiconductor?
Electron mobility The ability of an electron to move through a metal or semiconductor, in the presence of applied electric field is called electron mobility. It is mathematically written as V n = µ nE Let us consider a semiconductor that consists of large number of free electrons.
Is the mobility of an electron independent of the electric field?
However, mobility of electrons is independent of applied electric field i.e. change in electric field does not change the mobility of electrons. The SI unit of electric field is V/m, and the SI unit of velocity is m/s. Thus, the SI unit of mobility is m2/ (V.s).
How are electrons and holes different from each other?
The electrons therefore have better mobility as they have gained excitation energy and are further away from the region of influence of the nucleus. The holes are under the influence of nucleic forces and also have low excitation energy, therefore less mobility.