Conductivity of Hot Holes in Silicon at 77 °K

The conductivity of holes in p‐Si is measured as a function of electric field strength in the 〈100〉, 〈110〉, and 〈111〉 directions of crystals with different resistivities (6000 Ω cm ≧ ≧ Q300 °K ≧ 0.45 Ω cm) at 77 °K. The values obtained for samples from highly purified crystals are compared with the heavy hole mobility calculated theoretically within the framework of the same model which allowed to explain the dependence of mobility on lattice temperature. The different influence of the interaction with optical phonons on both the effects is caused by the non‐parabolic band structure, reflected more strongly by the field dependence of the mobility.