ABSTRACT
The ancient Greek philosopher Thales of Miletus is reputed to have discovered in around 600 b.c. that if a piece of amber is rubbed with wool or fur, it becomes electrically charged. This chapter discusses some of the basics of semiconductor physics. Electrical conductivity has units of reciprocal ohm-metres, although it is not unusual for conductivities to be quoted in reciprocal ohm-centimetres. Both the resistance and resistivity represent how much a material resists the flow of an electric current. Both the electrical conductivity and resistivity are dependent on temperature. The resistivity caused by defects is known as the “residual resistivity,” as unlike the thermal component of the resistivity, it still exists even if the temperature is near to absolute zero.
