Designing zero-dimensional dimer-type all-inorganic perovskites for ultra-fast switching memory

Resistive switching memory that uses halide perovskites (HP) has been considered as next-generation storage devices due to low operation voltage and high on/off ratio. However, the memory still faces challenges for stable operation with fast switching speed, which hinders the practical application. Thus, it should be considered from the stage of designing the HP for memory applications. Here, we design the perovskite memory using a high-throughput screening based on first-principles calculations. Total 696 compositions in four different crystal structures are investigated and essential parameters including stability, vacancy formation, and migration are considered as the descriptor. We select dimer-Cs3Sb2I9 as an optimal HP for memory; the device that uses dimer-Cs3Sb2I9 has ultra-fast switching speed (~20 ns) compared to the device that uses layer-Cs3Sb2I9 (>100 ns). The use of lead-free perovskite avoids environmental problems caused by lead in perovskite. These results demonstrate the feasibility to design the memory with ultra-fast switching speed.

Multi-color electrochromism from coordination nanosheets based on a terpyridine-Fe(ii) complex

A new metal complex electrochromic nanosheet with multiple color electrochromism, fast switching speed and excellent cyclic stability was prepared controllably by the liquid–liquid interface self-assembly method.

A high performance electroformed single-crystallite VO2 threshold switch

We investigated the threshold switching characteristics of an electroformed single crystal VO2 channel, it exhibits a high Ion/Ioff ratio of 143, a steep turn-on voltage slope of <0.5 mV dec−1 and a fast switching speed of 23 ns.

Next Generation Planar 1700 V, 20 mΩ 4H-SiC DMOSFETs with Low Specific On-Resistance and High Switching Speed

Due to their fast switching speed, knee-free forward characteristics, and a robust, low reverse recovery body diode, SiC MOSFETs are ideal candidates to replace silicon IGBTs in many high-power medium-voltage applications. 1700 V SiC MOSFETs have already been released to production at Wolfspeed based on its 2nd Gen technology. In this paper, we present our latest results in high voltage 4H-SiC MOSFET development. A low specific on-resistance of 4.7 mΩ⋅cm2 has been achieved on 1700 V, 20 mΩ 4H-SiC DMOSFETs at 250°C based on a 3rd generation planar MOSFET platform, which is less than half of the resistance of the previous generation devices. A detailed analysis has been carried out with respect to the static and dynamic characteristics, third quadrant conduction, and body diode reverse recovery charge, etc.