Alloys

1. By Samantha Thomas Alloys

2. Alloys • Alloy- a solid combination of atoms of two or more atoms . • The alloys are composed of “solid solutions” of two or more minerals • Thus one important strategy for modifying the properties of metals is to produce alloys , which have properties that differ from those of the component elements.

3. Semiconductors • Semiconductors -solid substance , such as silicon , with electrical conductivity between that of conductors and nonconductors at normal temperatures. • Semiconductors lay somewhere in between metals and nonmetals. • Semiconducting properties include geranium , tin , gallium arsenide , and cadmium sulfide. • Can be a metalloid !!

4. Doping • Doping- creates a situation in the solid silicon that allows charge carriers • Either electrons or tiny regions of positive charge –to become mobilized within the crystal. • This greatly improves silicon’s semiconductor charateristics.

5. Google: ___________ • Definition: An alloy is a substance made by melting two or more elements together, at least one of them a metal. An alloy crystallizes upon cooling into a solidsolution, mixture, or intermetalliccompound. • This definition is from : http://chemistry.about.com/od/dictionariesglossaries/g/defalloy.htm

6. Review questions : • What is a alloy? • Is a metalloid a semiconductor ?