White electroluminescence from SiN_x thin films by a PECVD equipment using dichlorosilane precursor and study of emission mechanism

In the present work SiN_x thin films, grown by PECVD technique using dichlorosilane, were used in electroluminescent device (EL) structure. Series of experiments were carried out by varying the flow of H₂ and SiH₂Cl_2, and after all the depositions and subsequent result analysis, a set of conditions were identified as M1, M2, M3, and M4 according to the physical thickness of the samples, their PL emission color and intensity of the emission. M3 and M4 conditions were identified as of key interest because of their intense whiteemission. After the photoluminescence (PL) analysis, EL was carried out, and a device structure was fabricated for the study. Role of quantum confinement effect was found for the white emission from the calculated nanocrystals from 2.5 to 5 nm. These results could be an important step for the establishment of optoelectronic devices such as silicon LEDs in the near future.