Sulphur doped silicon light emitting diodes

We report electroluminescence experiments from sulphur doped silicon light emitting diodes. Sulphur was implanted into boron doped silicon p-n junctions making use of dislocation engineering. The devices emit at 1.1 and 1.3 μm due to the Si TO phonon assisted transition and the sulphur related impurity, respectively. We show the effect of injection conditions on the silicon and sulphur emission. It is observed that the sulphur integrated intensity is increasing sublinearly, whereas the silicon integrated intensity is increasing superlinearly with increasing injection. We present a model which describes this behaviour showing that there are two major routes via the silicon and sulphur that take place, which are competing with each other, along with a non-radiative route coming from the sulphur related level. Our model describes the trends in our experimental data well.