The advancement of 6G technology relies on the development of high-performance terahertz detectors that can operate at room temperature. These detectors are crucial for Internet of Things (IoT) applications, which require sensitive environmental sensing and efficient reception of 6G signals. One significant research focus is on detection technology with high responsiveness and low equivalent noise power for 6G signals, which experience high losses in the air. To meet the demand for ultra-sensitive detectors in 6G technology, we have employed several techniques. Firstly, we prepared a large area of Weyl-semimetal layer through magnetron sputtering. Secondly, we obtained a high-quality Weyl-semimetal active layer by carefully controlling the annealing conditions. Next, a thin nano-Au layer was introduced as a micro-cavity reflection layer to enhance the device’s detection rate. Additionally, we incorporated an electromagnetic induction well to improve carrier confinement and enhance the detection sensitivity. This proposed high-performance terahertz detector, with its potential for industrial production, offers a valuable technical solution for the advancement of 6G technology.