1.11.1 Unbiased P-N Junction
If in a given material if the doping is not uniform then at one place large number of charge carriers exist while at other place small number of charge carriers exist. In a high charge carrier concentration area, all charge carriers are of similar type, either electrons or holes and hence start repelling each other. Due to this, charge carriers start moving from high cocentration area towards low concentration area, to achieve uniform concentration all over the meterial. This process is called diffusion and exists when there is nonuniform concentration of charge carriers in the material. In a p-n junction, on ท side there are large number of electrons while on p side electrons arc minority in number. So there is high