The drift mobility of holes in $n$-type silicon and electrons in $p$-type silicon has been measured as functions of impurity concentration and temperature. In single crystals of resistivity greater than 10 ohm-centimeter, the mobility at 300°K of holes is ${\mu }_P=500\mathrm{}\pm 50$ ${\mathrm{cm}}^2$/volt-sec and of electrons is ${\mu }_N=1200\mathrm{}\pm 100$ ${\mathrm{cm}}^2$/volt-sec. For this high-resistivity material, the temperature dependence of mobility in the same units is ${\mu }_N=5.5\mathrm{}\times {10}^6{T}^{-1.5\mathrm{}}$ and ${\mu }_P=2.4\mathrm{}\times {10}^8{T}^{-2.3\mathrm{}}$.

• Received 4 December 1953

DOI:https://doi.org/10.1103/PhysRev.93.1204