Which materials are primarily used as semiconductor substances?

The primary materials used as semiconductor substances are Germanium and Silicon. These materials have specific electrical properties that allow them to conduct electricity under certain conditions, making them ideal for use in semiconductor devices like transistors and diodes.

Silicon is the most widely used semiconductor in the electronics industry due to its abundance, favorable electronic characteristics, and the ability to form a native oxide layer (silicon dioxide), which is crucial for building integrated circuits. Germanium was one of the first materials used in semiconductor devices and possesses superior electron mobility compared to silicon; however, it is less stable at high temperatures and has largely been replaced by silicon in most applications.

Other materials listed, such as Copper, Aluminum, Gold, and Silver, are good conductors but not semiconductors. They do not have the property of being able to control electrical conductivity in the way that semiconductors do. Similarly, Carbon and Lead are typically not used as semiconductor materials; while carbon can form a type of semiconductor in specific structures (like graphene), in general discussions, Germanium and Silicon are recognized as the standard semiconductor materials.