Crystalline Ge3N4 on Ge(111)

The exposure of Ge(111) to a nitrogen plasma at temperatures above which Ge3N4 is thermally stable leads to the formation of a thin, monocrystalline Ge3N4 layer. At these temperatures, equilibrium is established between the formation and dissociation of Ge3N4, limiting its thickness to 0.7nm at ∼800°C. The thermal stability of a crystalline Ge3N4 layer is comparable to an amorphous one. It starts to evaporate at temperatures above 600°C. Crystalline Ge3N4 allows the growth of III-nitrides on top of Ge(111) substrates and possibly the passivation of Ge-based field effect transistors.