Non-volatile memory property of Er_2O_3 doped SnO_2 nanowires synthesized using GLAD technique

摘要

Er2O3 doped SnO2 nanowires (NWs) were synthesized on n-Si substrate by using glancing angle deposition technique. The fabricated Er2O3 doped SnO2 NWs were polycrystalline in nature as observed from X-ray diffraction (XRD), which was also verified using selected area electron diffraction analysis. The field emission scanning electron microscopy and transmission electron microscopy showed that the NWs were perpendicularly oriented with diameter and length of approximate to 40 nm and approximate to 300 nm respectively. After incorporation of Er2O3 in SnO2, a decrease in absorption and increase in band gap was observed due to the removal of oxygen vacancy related defects, which was also verified by the higher photoluminescence observed in Er2O3 doped SnO2 NW. Au metal contact was deposited over Er2O3 doped SnO2 NW to fabricate Au/ Er2O3 doped SnO2 NW/Si memory device. The Er2O3 doped SnO2 NW memory device showed higher performance as compared to undoped SnO2 NW memory device in terms of higher memory window of 2 V, higher charge storage capability, good endurance over 500 programming/erasing cycles as well as good retention properties with less charge loss rate of about 2 mV/decade due to efficient charge trapping mechanism. Moreover, the programme/erase process of the Er2O3 doped SnO2 NW device is explained with the help of band diagram.