Electronic radiation sources can be divided into vacuum electronic radiation sources and semiconductor radiation sources. As electronic radiation technologies advance toward higher frequencies, radiation power has become a bottleneck. The advantage of vacuum electronic devices lies in their ability to achieve high-efficiency, high-power output. However, to enhance radiation intensity in the terahertz band, optimization of the coupling effect between free electrons and micro/nano structures is crucial. A key to improving the efficiency of these devices is to better utilize micro/nano structures to strengthen the interaction between electrons and electromagnetic waves. Semiconductor radiation sources, particularly those based on plasmonic wave instabilities (Dyakonov-Shur effect), provide an innovative method of generating terahertz radiation through the excitation of two-dimensional electron gas in semiconductor materials. This mechanism has potential for covering a broad frequency range within the terahertz spectrum. Furthermore, optimizing the design of semiconductor heterostructures to improve the efficiency of plasmon wave excitation and amplification is a vital technology. By combining research on interactions between free electrons and micro/nano structures with studies on the amplification effects of plasmonic wave excitation in two-dimensional electron gases, a novel design approach has emerged. Such coupling of multiple mechanisms promises the development of more efficient terahertz radiation sources, not only pushing the boundaries of radiation power but also enabling applications in integrated circuits.