It was recalled that the rather low doping efficiency of P and B in amorphous hydrogenated material had long been explained in terms of the argument that almost all of either dopant was incorporated at 3-fold coordinated sites, and that both were inert or non-doping in this configuration. The energetic and structural consequences of B incorporation into amorphous hydrogenated material, with or without H passivation, had then been studied by using ab initio molecular dynamics techniques. This showed that the conventional view was wrong, and that the low doping efficiency in the case of B was due mainly to H passivation. The incorporation of P in amorphous hydrogenated material was similarly studied here, with and without passivation. In this case, the results supported the conventional view. It was concluded that P and B acted very differently in amorphous hydrogenated material. However, it was also found that the P-H complexes which passivated P in crystalline material were not even metastable in the amorphous hydrogenated material.

Theory of phosphorus doping in a-Si:H P.A.Fedders: Physical Review B, 1998, 58[11], 7020-3