The reporter learned from the Shenyang National Research Center for Materials Science, Institute of Metal Research, Chinese Academy of Sciences that the researchers of the advanced carbon materials research department of the center have prepared the vertical structure transistor "silicon-graphene-germanium transistor" with the Schottky junction as the emission junction for the first time. Reduce the delay time of graphene-based transistors by more than 1000 times, and increase its cut-off frequency from megahertz (MHz) to gigahertz (GHz). It will be expected to be used in high-speed devices in the terahertz (THz) field in the future. . The research results were published online recently in "Nature · Communication". In 1947, the first bipolar junction transistor (BJT) was born in Bell Labs, leading the human society into a new era of information technology. In the past few decades, increasing the working frequency of BJT has been an unremitting pursuit. High-speed devices such as heterojunction bipolar transistors (HBT) and hot electron transistors (HET) have been reported in succession. However, when the frequency needs to be further increased, these devices encounter bottlenecks: HBT's cut-off frequency is ultimately limited by the transit time of the base region, while HET is limited by the preparation of ultra-thin metal base regions with no holes and low resistance . In recent years, graphene has attracted attention as a two-dimensional material with excellent performance. It has been proposed to use graphene as a base material to prepare transistors. Its atomic thickness will eliminate the limitation of the transit time of the base region, and its ultra-high carrier Mobility also helps achieve high-quality, low-resistance base regions. "The currently reported graphene-based transistors generally use tunneling emitter junctions. However, the barrier height of tunneling emitter junctions severely limits the development prospect of the transistor as a high-speed electronic device." The head of the research team said. Through semiconductor thin film and graphene transfer process, they first prepared a vertical structure silicon-graphene-germanium transistor with Schottky junction as the emitter junction. The researcher said that compared with the reported tunneling junction, the silicon-graphene Schottky junction exhibits the largest on-state current and the smallest emitter junction capacitance, which results in the shortest emitter junction charging time, making the device The total delay time has been shortened by more than 1000 times, and the cut-off frequency of the device has been increased from about 1.0MHz to 1.2GHz. It is reported that our scientific researchers have analyzed various physical phenomena of the device at the same time, and based on experimental data modeling found that the device has the potential to work in the terahertz field, which will greatly improve the performance of graphene-based transistors. In the future, the foundation for ultra-high-speed transistors will be laid. Micro diaphragm pump,industrial pump,liquid transfer pump,diaphragm water pump,Gas diaphragm pump Changzhou Yuanwang Fluid Technology Co., Ltd. , https://www.ywfluid.com