Liquid phase epitaxy of binary III-V nanocrystals in thin Si layers triggered by ion implantation and flash lamp annealing

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.