With the rapid development of integrated circuits in accordance with Moore's Law, traditional single-gate silicon-based metal oxide semiconductor field effect transistors will soon reach their physical limits and will not be able to adapt to the development requirements of integrated circuits. There is an urgent need to develop new structures and new material field effect transistors. This project is carried out against this background. 1. The hysteresis mechanism of the current mdash;mdash; voltage characteristic curve of organic thin film transistors was revealed for the first time. It was found that when the formation/recombination of bipolarons is combined with the water/oxygen electrochemical reaction process, a hysteresis phenomenon is caused, which is a thermal activation process. The apparent activation energy of the disintegration of the bipolarons was found to be 0.29eV. A unified hysteresis model is established, which is generally applicable to band transmission in thin film transistors and jump conduction in semiconductor films, providing theoretical support for the application of thin film transistors in large-area integrated circuits and low-cost flexible displays. 2. The main mechanism of energy splitting at the top of the valence band of one to five layers of molybdenum dioxide was explored, and the physical mechanism of photoresponse of multiple layers of molybdenum dioxide was discovered. These are of great significance for understanding the electrical properties of transition metal disulfides, thus providing assistance for the application of these new materials in semiconductor devices. For double layers of molybdenum disulfide, interlayer coupling contributes more to phonon energy, but has little effect on band splitting, while coupling between spin and orbit has a greater effect on band splitting. We also observed that temperature-independent band splitting that occurs for single-layer materials can also occur in double-layer materials. In three-to five-layer materials, Bose-Einstein-type temperature-dependent valence band splitting dominates. Through research, we have ascertained the physical mechanism of the photoresponse of multilayer molybdenum disulfide and found that the generation and transmission of photocurrent in multilayer molybdenum dioxide are different from other low-dimensional materials, and both photovoltaic effects and photothermoelectric effects can exist. 3. Models of key parameters of girdle gates, dual gates, fin gates, and junctionless source/drain field effect transistors are established, and analytical expressions for important physical quantities such as channel potential, current mdash;mdash; voltage relationship, threshold voltage, subthreshold swing, and drain-induced barrier reduction effect of these new devices are obtained. In ultra-large-scale integrated circuits, because the cost of taping is expensive (ranging from hundreds of thousands to millions), the electrical behavior of the designed circuit must be simulated after the chip design is completed, and the taping can be carried out only after the design goals are achieved. Circuit behavior depends on device behavior, so it is important to establish an analytical model of a single device for this purpose. 4. For the first time, two methods of silicidation induced impurity segregation and diffusion using silicide as diffusion source are used to introduce high-concentration impurity atoms at the silicide/silicon interface and reduce the Schottky barrier height by 0.2eV, which can effectively promote metal source/drain application in integrated circuits; A complete scheme has been established to effectively extract the carrier mobility of thin film transistors using carbon nanotube networks as conductive materials that are independent of geometric parameters, thus solving a problem in the application of carbon nanotubes in thin film transistors. The research results were published 1 paper in Nature Communications, ACS Nano (impact factor 13.709) and IEEE Electron Device Letters, and 3 papers were published in IEEE Transactions on Electron Devices, an international high-end journal in the field of integrated circuit devices. The research results have been cited by high-end journals such as Nature Materials (impact factor 39.235), Nature Communications, and Nano Letters (impact factor 12.08), and 8 representative papers have been cited 155 times by SCI. Obtained 4 authorized invention patents.