Method of forming a nanocluster comprising dielectric layer and device comprising such a layer

A method of forming a dielectric layer (330) on a further layer (114, 320) of a semiconductor device (300) is disclosed. The method comprises depositing a dielectric precursor compound and a further precursor compound over the further layer (114, 320), the dielectric precursor compound comprising a metal ion from the group consisting of Yttrium and the Lanthanide series elements, and the further precursor compound comprising a metal ion from the group consisting of group IV and group V metals; and chemically converting the dielectric precursor compound and the further precursor compound into a dielectric compound and a further compound respectively, the further compound self-assembling during said conversion into a plurality of nanocluster nuclei (335) within the dielectric layer (330) formed from the first dielectric precursor compound. The nanoclusters may be dielectric or metallicinnature. Consequently, a dielectric layer is formed that has excellent charge trapping capabilities. Such a dielectric layer is particularly suitable for use in semiconductor devices such as non-volatile memories.