Silicon quantum dots in diamond matrix: A new synthesis route

Light-emitting layers of silicon quantum dots embedded in a diamond matrix have been prepared by using a new hybrid chemical vapour deposition-powder flowing technique. The polycrystalline diamond matrix is grown by thermal activation of CH 4-H 2 mixtures. The silicon nanoparticles used for the synthesis of the diamond-based composites were prepared by CO 2 laser pyrolysis of SiH 4-He mixtures in a gas flow reactor with controlled atmosphere. During the matrix deposition, the powder-flowing apparatus drives the silicon nanoparticles across the active area of the substrate, where diamond is growing. A strong room temperature emission is observed from composite films with characteristics dependent on the size distribution of the inserted silicon particles. We report details of the synthesis procedure and emission features of composite diamond films, whose properties promise high technological impact. Copyright © 2001 John Wiley & Sons, Ltd.