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Unformatted text preview: Semiconductor Materials Semiconductors are neither good conductors nor good insulators in their natural state. Each atom has four electrons in the valance (or outer) ring which are shared with adjacent atoms creating a very tight bonding between atoms (crystalline structure). The sharing of electrons in the valance rings of adjacent atoms is called covalent bonding. In this configuration, the electrons are not likely to move. Examples of semiconductors are silicon and germanium, with silicon being the most common. Other elements can be mixed (doped) with semiconductor materials to make them either a good conductor or a good insulator by changing the number of electrons in the valance ring. If silicon is doped with boron, aluminum, or gallium, (these elements have 3 electrons in their valance ring) the resulting material will become a conductor and allow electron movement. After doping, the electrons in the valance ring are still shared with adjacent atoms creating a crystalline structure; however, now there are...
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- Winter '12