Abstract
In recent years, particularly, metal–insulator–semiconductor (MIS) structures based on nano-dots are widely studied for their new physical phenomena as well as their potential applications in single-electron memory devices of the next generation. Transmission electron microscopy (TEM) showed that Si NDs embedded in the silicon nitride (SiNx) thin film have been fabricated by plasma enhanced chemical vapor deposition technique, and the sheet density is the order of 1011–1012 cm-2. Charge trapping and storage in nc-Si were exhibited in capacitance–voltage (C–V) measurements at room temperature through the hysteresis and shift of the flat-band voltage (ΔVFB) of the nc-Si samples.In the nitride memory, we know there are many deep energy-level of defect traps in this sample, and the carriers transport at low electric-field with hopping trapping named Poole-Frenkle emission. In the silicon oxide thin film, the carriers transport at high electrical–field names Fowler-Norhdiem effect tunneling, as is known to all.Differ from the storage media containing two kinds of discrete charge storage centers: nitride traps in the case of SONOS and isolated Si nanocrystals in the flash memory, the Si NDs embedded in the (SiNx) thin film grown by plasma enhanced chemical vapor deposition has a larger window size of hysteresis in C-V curve. In this study, we observed the two different hysteresis phenomenon measured with the same repeated sweep voltage in the same device. We try to analyze the relationship between memory effect and the ratio of SiH4 and N2, and the different memory phenomenon from the traps and the silicon nano-dots. The Other thing is to investigate the carrier transport mechanism in the SiNx thin film.