Observation of negative differential resistance in SiO2/Si heterostructures

Abstract

The negative differential resistance (NDR) effect been widely reported in the physical systems of traditional semiconductors, and corresponding theoretical mechanisms are known and applied. However, exploring the origin of NDR phenomena emerging in new structures or conditions remains a worthwhile challenge. Here, we report an experimental observation of an NDR effect based on SiO 2 /Si heterojunctions by injecting photo-generated carriers via vacuum ultraviolet (VUV) irradiation. We propose a complex competition mechanism between trap centers’ and recombination centers’ dominating carrier transport behavior. This is caused by the difference in spatial distribution of density of band-tail states and defect states in SiO 2 /Si. This work may inspire further consideration of SiO 2 /Si heterojunctions for electronic applications. • NDR effect is observed in SiO 2 /Si heterojunction via vacuum VUV irradiation • NDR effect originates from difference in spatial distribution of density of states • SiO 2 /Si heterojunction with NDR effect shows potential for space applications Using vacuum ultraviolet irradiation, Jia et al. observe a negative differential resistance effect in the structure of SiO2/Si heterojunction. This work may bring new opportunities for traditional SiO 2 /Si heterojunctions in electronic applications, such as switches and amplifying elements in space detection systems.