We report the improvement in silicon band-edge emission when defects are deliberately introduced in the lattice structures. Silicon is a poor light-emitter due to its indirect bandgap nature. This ...paper aims to increase the intensity of the light emission from silicon by implantation of boron which will lead to the formation of dislocation loops between the lattice structures. Prior to that, the silicon samples were implanted with high concentration of carbon. Photoluminescence (PL) measurements were carried out to observe the emission in silicon at near infrared region. The temperatures were varied from 10K to 100K to study the effect of temperature towards the peak luminescence intensity. By observing the PL spectra, there are two main peaks that can be seen at ~1112 nm and 1170 nm. Both peaks show significantly higher intensities in the samples incorporated with boron.
Muonium, with a positive muon as the nucleus is considered a light isotope of hydrogen displaying a close chemical analogy to this atom. It offers a unique opportunity to study the behaviour of ...hydrogen in diamond at very low concentrations. The mass difference, however, implies that dynamical effects will be distinct. The bond centred muonium (MuBC) state in diamond is easily observed and there is a very good correlation between theoretical and experimental hyperfine parameters ((4)). Curiously, despite its predicted stability, the bond centred hydrogen state has not yet been observed in diamond. Following the discovery of hydrogen dopant states in certain wide band gap metal oxides, and the possibility of hydrogen related molecular dopants in diamond, the study of hydrogen in diamond is important. Although it is evident from its hyperfine parameters that (MuBC) is not a shallow donor, the question still arises as to where the (MuBC) state in diamond might lie in the band gap. Accordingly, measurements of the high temperature stability of (MuBC) have been performed in a search for its possible ionization. The results are consistent with such an ionization, as the disappearance of MuBC polarisation (setting in near 1000 K) is correlated with the slight increase in the population of the diamagnetic μ+ species.
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