Measurement of the drift velocities of electrons and holes in high-ohmic [formula omitted] silicon

Abstract

Measurements of the drift velocities of electrons and holes as functions of electric field and temperature in high-purity n- and p-type silicon with 〈100〉 lattice orientation are presented. The measurements cover electric field values between 2.5 and 50kV/cm and temperatures between 233 and 333K. For both electrons and holes differences of more than 15% are found between our 〈100〉 results and the 〈111〉 drift velocities from literature, which are frequently also used for simulating 〈100〉 sensors. For electrons, the 〈100〉 results agree with previous 〈100〉 measurements; however, for holes differences between 5 and 15% are observed for fields above 10kV/cm. Combining our results with published data of low-field mobilities, we derive parametrizations of the drift velocities in high-ohmic 〈100〉 silicon for electrons and holes for fields up to 50kV/cm, and temperatures between 233 and 333K. In addition, new parametrizations for the drift velocities of electrons and holes are introduced, which provide somewhat better descriptions of existing data for 〈111〉 silicon than the standard parametrization.