On the 15th, the reporter learned from the Institute of Metals of the Chinese Academy of Sciences that researchers Liu Chi and Sun Dongming of the Institute worked with a research team led by Cheng Huiming, an academician of the CAS Member, to invent a "hot emitter" transistor composed of mixed dimensional materials such as graphene and germanium, and proposed a new "stimulated emission" hot carrier generation mechanism. The relevant research results were published on the 15th in the academic journal Nature. Transistors are the fundamental units of integrated circuits. As the size of transistors continues to shrink, the technological challenges for their further development are increasing. Researchers have introduced that just like the valve of a faucet can regulate the size of water flow, transistors can also regulate the size of current formed by charge carriers such as electrons or holes. Normally, when carriers are in thermal equilibrium with the surrounding environment, it is called a "steady state". However, by using methods such as electric field acceleration, the energy of carriers can be increased, making them "hot carriers". If this high-energy hot carrier can be effectively controlled and its concentration can be increased, it is expected to further improve the speed and function of transistors. The research team has invented a "hot emitter" transistor composed of mixed dimensional materials such as graphene and germanium by controllable modulation of hot charge carriers to increase current density, and proposed a novel "stimulated emission" hot charge carrier generation mechanism. It is reported that this new transistor consists of two coupled "graphene/germanium" Schottky junctions. Carriers are injected from the graphene base and then diffuse to the emitter, exciting carriers heated by an electric field, resulting in a sharp increase in current. This design requires a voltage change of less than 1 millivolt for every order of magnitude change in transistor current, breaking the Boltzmann limit of traditional transistors. In addition, the transistor exhibits a negative differential resistance with a peak to valley current ratio exceeding 100 at room temperature, demonstrating its potential for application in multi value logic calculations. Researchers say that this study has opened up a new field of transistor device research by increasing current density through controllable modulation of hot carriers, adding new members to the hot carrier transistor family. (New Society)