Why does electron mobility in semiconductors generally decrease as temperature increases?

In semiconductors, electron mobility refers to the ease with which charge carriers move through a crystal lattice under the influence of an electric field. As temperature increases, this mobility generally decreases because of increased scattering caused by lattice vibrations.12

In a solid crystal, atoms are arranged in a repeating pattern and behave as if connected by tiny springs. As the material's thermal energy rises, these atoms oscillate more vigorously, generating mechanical waves known as phonons. Because charge carriers (electrons and holes) must travel through this lattice, they frequently collide with these vibrating atoms.231

At higher temperatures, the increased frequency and intensity of these lattice vibrations lead to more frequent collisions, which impede the progress of the charge carriers. This increased rate of scattering reduces the carriers' drift velocity for a given electric field strength, thereby lowering their overall mobility.132