High optical power density of 0.5 mW/cm2, external quantum efficiency of 0.1%, and population inversion of 7% are reported from Tb+-implanted silicon-rich silicon nitride/oxide light emitting devices. Electrical and electroluminescence mechanisms in these devices were investigated. The excitation cross section for the 543 nm Tb3+ emission was estimated under electrical pumping, resulting in a value of 8.2 × 10−14 cm2, which is one order of magnitude larger than one reported for Tb3+:SiO2 light emitting devices. These results demonstrate the potentiality of Tb+-implanted silicon nitride material for the development of integrated light sources compatible with Si technology.

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Rare earth doped metal-oxide-semiconductor (MOS) structures are of great interest for Si-based light emission. However, several physical limitations make it difficult to achieve the performance of light emitters based on compound semiconductors. To address this point, in this work the electroluminescence (EL) excitation and quenching mechanism of Er-implanted MOS structures with different designs of the dielectric stack are investigated. The devices usually consist of an injection layer made of SiO2 and an Er-implanted layer made of SiO2, Si-rich SiO2, silicon nitride, or Si-rich silicon nitride. All structures implanted with Er show intense EL around 1540 nm with EL power efficiencies in the order of 2 × 10−3 (for SiO2:Er) or 2 × 10−4 (all other matrices) for lower current densities. The EL is excited by the impact of hot electrons with an excitation cross section in the range of 0.5–1.5 × 10−15 cm−2. Whereas the fraction of potentially excitable Er ions in SiO2 can reach values up to 50%, five times lower values were observed for other matrices. The decrease of the EL decay time for devices with Si-rich SiO2 or Si nitride compared to SiO2 as host matrix implies an increase of the number of defects adding additional non-radiative de-excitation paths for Er3+. For all investigated devices, EL quenching cross sections in the 10−20 cm2 range and charge-to-breakdown values in the range of 1–10 C cm−2 were measured. For the present design with a SiO2 acceleration layer, thickness reduction and the use of different host matrices did not improve the EL power efficiency or the operation lifetime, but strongly lowered the operation voltage needed to achieve intense EL.

The integration of III–V compound semiconductors in Si is a crucial step towards faster and smaller devices in future technologies. In this work, we investigate the formation process of III–V compound semiconductor nanocrystals, namely, GaAs, GaSb, and InP, by ion implantation and sub-second flash lamp annealing in a SiO2/Si/SiO2 layer stack on Si grown by plasma-enhanced chemical vapor deposition. Raman spectroscopy, Rutherford Backscattering spectrometry, and transmission electron microscopy were performed to identify the structural and optical properties of these structures. Raman spectra of the nanocomposites show typical phonon modes of the compound semiconductors. The formation process of the III–V compounds is found to be based on liquid phase epitaxy, and the model is extended to the case of an amorphous matrix without an epitaxial template from a Si substrate. It is shown that the particular segregation and diffusion coefficients of the implanted group-III and group-V ions in molten Si significantly determine the final appearance of the nanostructure and thus their suitability for potential applications.