What is semiconductor?
A1 Semiconductor is material having nature intermediate between conductor and insulator. Current can easily flow through conductor, while it cannot through insulator. Although semiconductor is not insulator, little current flows through its element. Conductor such as metals contains many free electrons, and these electrons easily move. As a result, current flows through conductor. At first, germanium (Ge) was used as the element of semiconductor. At present, silicon (Si) is mainly used. Usually, the expression of a semiconductor device means what is made from semiconductor. For example, pure silicon hardly conducts electricity, but if it is mixed with other element (by means of ion implantation with high-temperature diffusion: doping), the resultant mixture could conduct electricity. By doping elements with various characteristics to silicon, various operations can be realized. For the production process of semiconductor devices, refer to “How Semiconductors Are Made” on NEC Electronic
