Great Potential of Si-Te Ovonic Threshold Selector in Electrical Performance and Scalability

Abstract

The selector is an indispensable section of the phase change memory (PCM) chip, where it not only suppresses the crosstalk, but also provides high on-current to melt the incorporated phase change material. In fact, the ovonic threshold switching (OTS) selector is utilized in 3D stacking PCM chips by virtue of its high scalability and driving capability. In this paper, the influence of Si concentration on the electrical properties of Si-Te OTS materials is studied; the threshold voltage and leakage current remain basically unchanged with the decrease in electrode diameter. Meanwhile, the on-current density (Jon) increases significantly as the device is scaling down, and 25 MA/cm2 on-current density is achieved in the 60-nm SiTe device. In addition, we also determine the state of the Si-Te OTS layer and preliminarily obtain the approximate band structure, from which we infer that the conduction mechanism conforms to the Poole-Frenkel (PF) model.

Indium turns tellurium into an ovonic threshold switching selector via a stabilizing amorphous network

“…The on/off ratio of InTe 9 devices is larger than that of Si–Te OTS devices from a previous work, which is less than 10 4 . 35 Fig. 1(g) presents the relationship between I off and the feature size of OTS devices.…”

Editorial for the Special Issue “Amorphous and Nanocrystalline Semiconductors: Selected Papers from ICANS 29”

“…This includes topics such as Si-based, oxide, perovskite, 2D thin films and nanostructures, device applications for TFTs, solar cells, and LEDs, as well as memory devices and emerging flexible electronics and neuromorphic applications. For example, new fabrication technologies of amorphous and nanocrystalline thin films, electronic and optical characteristics, and device applications are presented and discussed in [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ], including theoretical work in an ab initio study [ 9 ], controllable growth and formation of Si nanowires [ 1 ], nanocrystals [ 2 ], and quantum dots [ 3 , 4 ]. There are also several papers that cover emerging memory devices.…”

“…There are also several papers that cover emerging memory devices. These include phase change memory [ 5 , 6 , 7 , 8 , 9 ] based on amorphous chalcogenide thin films and memristors based on transition metal oxides acting as an artificial synapse [ 10 , 11 , 12 ]; the improvement of electro-luminescence (EL) efficiency Er-doped oxide thin films [ 13 , 14 , 15 ]; 2D semiconductor thin films and perovskite for solar cells and aqueous Zn-air battery [ 16 , 17 , 18 , 19 ]; and flexible electronic materials for integrated strain sensors [ 20 , 21 ]. We anticipate that this Special Issue should interest a broad audience in these related fields.…”

“…However, the second drop is related to the increase in carrier mobility. In order to suppress the crosstalk and provide a high on-current to melt the incorporated phase change materials in the PCRAM array and 3D stacking chips, the authors [ 8 ] investigated the influence of Si concentration on the electrical properties of the Si-Te ovonic threshold selector. The results showed that the threshold voltage and leakage current remain basically unchanged with the electrode size scaling down.…”