Passivation property of SiNx:H/SiO2 double layer formed by ammonia microwave remote plasma CVD method

We evaluated the passivation property of SiN_x:H/SiO₂ double layers formed at various temperatures by using hydrogen radical annealing. The passivation property was analyzed by measuring effective lifetime and interface state density. The effective lifetime and the interface state density depended strongly on the deposition temperature of SiN_x:H layers. The effect of hydrogen radical annealing for SiN_x:H/SiO₂ double layer´s was weakened with an increase in deposition temperature of SiN_x:H. It was speculated that the annealing effect depending on deposition temperature was caused during deposition. At the deposition temperature of 350°C, the annealing effect during deposition was nearly equal to the hydrogen radical annealing effect after the deposition. The annealing with ammonia afterglow plasma improved effectively the effective lifetime in SiO₂/c-Si single layers. When the deposition time is chosen, the annealing effect should be taken into consideration.