A region of transition between semiconductor layers; such as, a p/n junction, which goes from a region that has a high concentration of acceptors (p-type) to one that has a high concentration of donors (n-type).

The area of immediate contact between two layers (positive and negative) of a photovoltaic cell.

The junction lies at the center of the cell barrier or depletion zone.

A photovoltaic (PV) generator junction box is an enclosure on the module where PV strings are electrically connected and where protection devices can be located, if necessary.

A semiconductor device with a junction and a built-in potential that passes current better in one direction than the other. All solar cells are junction diodes.

A compound cell made of different semiconductor materials in layers, one above the other.

Sunlight entering the top passes through successive cell barriers, each of which converts a separate portion of the spectrum into electricity, thus achieving greater total conversion efficiency of the incident light.