A composite material for broad photoluminescence (PL) from asymmetry to more symmetry-like was proposed by the formation of Si nanocrystals (nc-Si), SiC nanoparticles (np-SiC) and sp2 carbon cluster which were made from the two-layer C/Si on Si(1 0 0) using rapid-thermal-annealing at 750 C for 1 min. The effect of underlying Si layer thickness on the microstructure and broad PL of the annealed carbon and two-layer C/Si films has been investigated. Fourier-transform-infrared-absorption spectra indicated that very weak Si-C bonding peak was observed for the annealed single-C film and the enhanced intensity occurred at two-layer C/Si films with underlying thickness of 10-25 nm. Compared to the single-C film, the two-layer C/Si film was beneficial for formation of SiC which increased with Si thickness. A more symmetry-like broad PL band around 400-700 nm was observed at the annealed C/Si films with higher Si thickness of 25 nm while the annealed C film has weak and narrow band. Also, the enhanced symmetry-like PL band was attributed to more amount of np-SiC formation at the bottom of C/Si film together with reduced C thickness which can be potentially applied into white light emission material. The detailed mechanism of broad PL was proposed in terms of microstructure evolution.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry