What is a Dopant?
A dopant is a substance which is added to a crystal lattice with the intention of changing its conductive properties. The term is most widely used in the chip manufacturing industry, where dopants are added to the silicon and germanium wafers used in the manufacture of computer chips. Other crystal lattices including those used in the manufacture of some optical equipment are also doped, however. Many dopants are extremely toxic, leading to widespread pollution in factories which fail to control their chemicals. Silicon Valley, for example, is heavily contaminated with the remains of chip manufacture. A dopant works by altering the number of free electrons in a crystal lattice, thereby making it more conductive. In the example of silicon, the element typically forms a uniform crystal lattice in which each atom bonds to four neighbors. When a dopant with five bonding electrons is introduced, the result is free electrons, creating a negative charge. A dopant with three bonding electrons
