A thermionic-diffusion model of polysilicon emitter

A model has been developed to characterize the hole current through an n-type polysilicon emitter in terms of thermionic emission acting in series with drift-diffusion. The thermionic emission results from the steep potential barrier which is induced by impurity segregation at the polysilicon-silicon interface. The total hole current, according to this model, depends on the peak doping concentration and the Gummel number of the monosilicon region of the emitter.