A semiconductor combines the properties of a conductor and an insulator. Semiconductors are materials that have a low connectivity at low temperatures. With the addition of heat, however, or other variables, including voltage and light, their conductivity can be improved.
The vast majority of solid-state electronics are built upon semiconductors. Some of the products produced with semiconductors include light emitting diodes, transistors, solar cells and more. These materials are found in the most advanced technologies, as well, including quantum dots.
Some semiconductors are put through a process called doping. This involves adding impurities to the semiconductor, which changes the conductivity of it. Another form of doping is adding light or an electric field to the semiconductor, again changing its conductivity properties.
Semiconductors are particularly useful in applications where the connectivity of material needs to be changed deliberately. This allows them to change the energy input into a circuit, amplify the energy input, operate as a switch and to perform many other tasks that may be required for an electronic product to function.