PN Junction

Question 1

Quasi-Fermi-Level Formula

Answer 1

pn > ni*2

Question 2

How is the maximum voltage of a solar cell?

Answer 2

Is equal to the separation of the Quasi-Fermi-levels and not to the band gap

Question 3

The three physical loss mechanism- Part 2

Answer 3

Every photon can generate only one electron-hole pair. Photon energy in excess of the semiconductor band gap is lost (Thermalization).
Photons with energies lower than the band gap can not generate an electron-hole pair. (Non-absorption loss)

Question 4

How is the conductivity in a pn junction?

Answer 4

Extremely different in both regions

Question 5

Is the Fermi energy constant across a pn junction in equilibrium?

Answer 5

Yes

Question 6

What is the filling level of electrons?

Answer 6

The level that is constant throughout the junction. (This level is denoted by the Fermi Level)

Question 7

Vacuum level in a PN junction in equilibrium

Answer 7

It is not constant

Question 8

What is the width of the SCR (Space Charge Region) in relation to the total width?

Answer 8

Less than the 1%

Question 9

What type of carrier transport in most of the solar cell is present in a pn junction in equilibrium?

Answer 9

Diffusion ( no electrical field)