What is the name of the science theory describing the maximum possible efficiency of a single solar cell (you'll need to do some homework as this wasn't covered in the lecture)?

Photovoltaic cells have been around since the 1950s, but when was the first mono-crystalline silicon cell developed with an efficiency greater than 20%?

The bus bar fingers on the top of the solar cell (which receive the electrons) can be as wide as possible to maximise the chances of picking up the electrons before recombination occurs.

Which of these combinations less to the lowest reflectivity?

The fill factor is the ratio of the square defined by the Jsc and Voc values integral over the observed JV curve

The efficiency of a solar cell is described by:

The doping of the semiconductor material alters the fermi level.  By adding more electrons in the n-type material, the fermi level is increased, and by removing electrons, the fermi level in the p-type material is decreased.  At the PN junction, the fermi levels must be the same, so this effectively moves the valence energy down for the n-type and up for the p-type, creating an energy 'waterfall'.

The PN junction can only occur when the Si is above 0K, as at 0K all the electrons are below the fermi level are the are no electrons in the conductance band.

When a p-type and an n-type wafer of Si are first brought together, which of these events occur:

N-type material is so called because it is rich in electrons compared to pure Si, and so electron can easily flow through the material.  P-type material is so called because with the substitution of Si for Boron, it has fewer electron (=more holes) which makes the flow of holes easier.