When sunlight strikes the cell, it creates electron-hole pairs. The negatively charged electrons move through the semiconductor material to produce an electric current, while the positively charged holes move in the opposite direction. . This incomplete bond becomes a hole. How an N-type Semiconductor Is Formed Start again with pure silicon. Add a small amount of Phosphorus (P) — a pentavalent impurity (5. . This absorption generates pairs of negative and positive charges, known as electron-hole pairs. You'd think holes going in. . Photovoltaic cells are made of semiconducting materials (usually silicon) with impurities added to certain regions to create either a surplus of electrons (n -type doping) or a scarcity of electrons (p -type doping, also called a surplus of holes).
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