Temperature is one of the most, if not the most, important parameter
in semiconductors. A dictionary will tell you that temperature is
the degree of hotness or coldness relative to a standardized scale.
You should be accustomed to the Celsius scale by now; it was established
with reference values set to the freezing and boiling of water. We
will typically talk about the absolute scale, in degrees Kelvin, which
is written as 300 K or 0 K, etc., without a degree symbol because it is
absolute temperature. (need to review? check
Why is temperature important? The average energy of a solid --
and its components (atoms, electrons, etc.) -- is measured by its temperature.
The higher the temperature, the more (thermal) energy is available to be
used by the atoms and electrons. Since we are talking about "electronic"
devices, and temperature has a significant impact on the behavior of electron,
temperature must have a significant impact on the behavior of electronic
Temperature directly impacts:
Carrier concentrations -- by impacting:
or, in words, the average kinetic energy of an electron in a solid is linearly
proportional to the temperature of the solid. For room temperature,
we find that the average velocity of a free electron is approximately 107cm/sec.