The present invention discloses a method of improving an electroluminescent efficiency
of a MOS device by etching a semiconductor substrate thereof. A chemical etching
process is performed to remove surface states or surface defects located on the
surface of a silicon substrate before a nanoparticle layer and a conducting layer
is formed on the silicon substrate, in order that the non-radiative electron-hole
recombination centers located on the surface of silicon substrate is suppressed.
Accordingly, the percentage of radiative electron-hole recombination is heightened
and the electroluminescent efficiency of a MOS light emitting device is drastically
enhanced. Advantageously, the chemical etching step is able to create a nanostructure
on the surface of the silicon substrate to increase the probability of the collision
of electron-hole pairs and phonons, and the electroluminescent efficiency of a
MOS light emitting device is improved as well.
