What are semiconductors?

Semiconductors possess specific electrical properties. A substance that conducts electricity is called a conductor, and a substance that does not conduct electricity is called an insulator. Semiconductors are substances with properties somewhere between them. ICs(integrated circuits) and electronic discrete components such as diodes and transistors are made of semiconductors. Common elemental semiconductors are silicon and germanium. Silicon is well-known of these. Silicon forms most of ICs. Common semiconductor compounds are such as gallium arsenide or indium antimonide.
Semiconductors became essential for many electronic appliances as well as for social infrastructure that support our everyday life.
Semiconductors play an important role in equipment control in a variety of fields, such as operating air conditioners at a comfortable room temperature, improving automobile safety, laser treatment in cutting-edge medical care and many more. Moreover, the advances of semiconductor technology have driven systems efficiency, miniaturization and energy savings, which in turn help to preserve the global environment in addition to achieving safe and comfortable life and to create prosperous future.
Semiconductors were discovered all the way back in 19th century. In the 1940s, transistors were invented. Radios, which used vacuum tubes until then, were significantly downsized and became portable.
A widely known semiconductor is silicon. Electronic components using semiconductors are called semiconductor devices, including the IC, which is an integrated circuit of transistors. Semiconductor devices mounted inside many electronics appliances are important electronic components that support our everyday live.