Electrical measurement of electron and hole mobilities as a function of injection level in silicon

The first experimental method to separately measure the hole and the electron mobilities as a function of the injection level is presented. The carrier mobilities are extracted from impulsive measurements of the resistance associated with a n/sup +/-/spl nu/-n/sup +/ (p/sup +/-/spl pi/-p/sup +/) structure, where the conductivity of the intermediate layer is controlled by the injection of an incorporated p-n junction diode. Two-dimensional numerical simulation is used to assess the accuracy of the proposed measurement technique. Experimental results obtained at room temperature on both n-type and p-type materials are presented and compared to existing analytical mobility models.