Influencing factors of electrical conductance
1. Temperature
Electrical conductivity has a great correlation with temperature. The conductivity of metal decreases with increasing temperature. The electrical conductivity of semiconductors increases with increasing temperature. Within a range of temperature values, the conductivity can be approximately proportional to the temperature. In order to compare the electrical conductivity of substances at different temperature conditions, a common reference temperature must be set. The correlation between conductivity and temperature can often be expressed as the slope of conductivity versus upper temperature line graph.
2. Degree of doping
The doping degree of solid-state semiconductors will cause great changes in electrical conductivity. Increasing the doping level will increase the conductivity. The conductivity of an aqueous solution depends on the concentration of solute salts contained in it, or other chemical impurities that will decompose into electrolytes. The conductivity of a water sample is an important indicator for measuring the salt content, ion content, and impurity content of water. The purer the water, the lower the conductivity (the higher the resistivity). The conductivity of water is often recorded in terms of conductivity; conductivity is the conductivity of water at 25°C.
3. Anisotropy
Some substances have anisotropic conductivity, which must be expressed in a 3 X 3 matrix (using mathematical terms, second-order tensor, usually symmetrical).