Recombination current for p-i-n junctions based on compensated semiconductor materials

An energy diagram of a p-i-n junction made of compensated semiconductor materials involving electrically active deep recombination r-levels is proposed. The mechanism of current flow for forward bias under nonequilibrium charge carriers trapping and recombination in the high-resistance i-region formed due to the r-levels over compensation are analyzed. In the case of trapping: a) the nonequilibrium charge carriers lifetimes (tau) n does not equal (tau) p and the electron filing function fn of r-levels are space- dependent; b) for injected carriers the potential wells separated by barriers are formed near then- and p-regions. An analysis of the corresponding recombination statistics gives a complicated shape of the I-V-curve, with a section where the ideality coefficient v varies in the 1 < v 2 divided by 4 ranges. Nonequilibrium charge carriers tunneling through the barriers is possible at low temperatures.