Electrical and dielectric properties of ferromagnetic GeMn nanocrystals embedded in metal-oxide-semiconductor Schottky diodes (Al/SiO2: GeMn NCs/n-Si) grown by MBE

This study examines the electrical and dielectric characteristics of magnetic GeMn nanocrystals integrated into a metal-insulator-semiconductor (MOS) configuration for optoelectronic applications. The nanocrystals were produced by solid-state dewetting of an amorphous GeMn layer deposited by MBE on SiO2/Si. The nanocrystals exhibit a well-defined hemispheric shape, high homogeneity, and with a Curie temperature higher than that of the ambient temperature. Characterizations by transmission electron microscopy (TEM) coupled with energy-dispersive X-ray spectroscopy (EDS) revealed the crystallinity of the nanocrystals and optimal incorporation of manganese in the nanocrystals, eliminating the usual diffusion or segregation anomalies observed during growth of GeMn alloy on silicon or germanium. Electrical and dielectric tests conducted via current-voltage and impedance spectroscopies on these