What are semiconductors?

Semiconductors are element whose properties are intermediate between those of metals and solid nonmetals.

Where are they found?

The metalloids; boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At) are the elements found along the step like line between metals and non-metals of the periodic table.

How are they used

They are used in the periodic table.